diff options
Diffstat (limited to 'Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h')
-rw-r--r-- | Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h | 6945 |
1 files changed, 3584 insertions, 3361 deletions
diff --git a/Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h b/Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h index 96644046e45..4f2eaca6919 100644 --- a/Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h +++ b/Build/source/libs/freetype2/freetype-src/include/freetype/freetype.h @@ -1,19 +1,19 @@ -/***************************************************************************/ -/* */ -/* freetype.h */ -/* */ -/* FreeType high-level API and common types (specification only). */ -/* */ -/* Copyright 1996-2018 by */ -/* David Turner, Robert Wilhelm, and Werner Lemberg. */ -/* */ -/* This file is part of the FreeType project, and may only be used, */ -/* modified, and distributed under the terms of the FreeType project */ -/* license, LICENSE.TXT. By continuing to use, modify, or distribute */ -/* this file you indicate that you have read the license and */ -/* understand and accept it fully. */ -/* */ -/***************************************************************************/ +/**************************************************************************** + * + * freetype.h + * + * FreeType high-level API and common types (specification only). + * + * Copyright (C) 1996-2019 by + * David Turner, Robert Wilhelm, and Werner Lemberg. + * + * This file is part of the FreeType project, and may only be used, + * modified, and distributed under the terms of the FreeType project + * license, LICENSE.TXT. By continuing to use, modify, or distribute + * this file you indicate that you have read the license and + * understand and accept it fully. + * + */ #ifndef FREETYPE_H_ @@ -39,56 +39,55 @@ FT_BEGIN_HEADER - /*************************************************************************/ - /* */ - /* <Section> */ - /* header_inclusion */ - /* */ - /* <Title> */ - /* FreeType's header inclusion scheme */ - /* */ - /* <Abstract> */ - /* How client applications should include FreeType header files. */ - /* */ - /* <Description> */ - /* To be as flexible as possible (and for historical reasons), */ - /* FreeType uses a very special inclusion scheme to load header */ - /* files, for example */ - /* */ - /* { */ - /* #include <ft2build.h> */ - /* */ - /* #include FT_FREETYPE_H */ - /* #include FT_OUTLINE_H */ - /* } */ - /* */ - /* A compiler and its preprocessor only needs an include path to find */ - /* the file `ft2build.h'; the exact locations and names of the other */ - /* FreeType header files are hidden by preprocessor macro names, */ - /* loaded by `ft2build.h'. The API documentation always gives the */ - /* header macro name needed for a particular function. */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * header_inclusion + * + * @title: + * FreeType's header inclusion scheme + * + * @abstract: + * How client applications should include FreeType header files. + * + * @description: + * To be as flexible as possible (and for historical reasons), FreeType + * uses a very special inclusion scheme to load header files, for example + * + * ``` + * #include <ft2build.h> + * + * #include FT_FREETYPE_H + * #include FT_OUTLINE_H + * ``` + * + * A compiler and its preprocessor only needs an include path to find the + * file `ft2build.h`; the exact locations and names of the other FreeType + * header files are hidden by @header_file_macros, loaded by + * `ft2build.h`. The API documentation always gives the header macro + * name needed for a particular function. + * + */ - /*************************************************************************/ - /* */ - /* <Section> */ - /* user_allocation */ - /* */ - /* <Title> */ - /* User allocation */ - /* */ - /* <Abstract> */ - /* How client applications should allocate FreeType data structures. */ - /* */ - /* <Description> */ - /* FreeType assumes that structures allocated by the user and passed */ - /* as arguments are zeroed out except for the actual data. In other */ - /* words, it is recommended to use `calloc' (or variants of it) */ - /* instead of `malloc' for allocation. */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * user_allocation + * + * @title: + * User allocation + * + * @abstract: + * How client applications should allocate FreeType data structures. + * + * @description: + * FreeType assumes that structures allocated by the user and passed as + * arguments are zeroed out except for the actual data. In other words, + * it is recommended to use `calloc` (or variants of it) instead of + * `malloc` for allocation. + * + */ @@ -101,219 +100,219 @@ FT_BEGIN_HEADER /*************************************************************************/ - /*************************************************************************/ - /* */ - /* <Section> */ - /* base_interface */ - /* */ - /* <Title> */ - /* Base Interface */ - /* */ - /* <Abstract> */ - /* The FreeType~2 base font interface. */ - /* */ - /* <Description> */ - /* This section describes the most important public high-level API */ - /* functions of FreeType~2. */ - /* */ - /* <Order> */ - /* FT_Library */ - /* FT_Face */ - /* FT_Size */ - /* FT_GlyphSlot */ - /* FT_CharMap */ - /* FT_Encoding */ - /* FT_ENC_TAG */ - /* */ - /* FT_FaceRec */ - /* */ - /* FT_FACE_FLAG_SCALABLE */ - /* FT_FACE_FLAG_FIXED_SIZES */ - /* FT_FACE_FLAG_FIXED_WIDTH */ - /* FT_FACE_FLAG_HORIZONTAL */ - /* FT_FACE_FLAG_VERTICAL */ - /* FT_FACE_FLAG_COLOR */ - /* FT_FACE_FLAG_SFNT */ - /* FT_FACE_FLAG_CID_KEYED */ - /* FT_FACE_FLAG_TRICKY */ - /* FT_FACE_FLAG_KERNING */ - /* FT_FACE_FLAG_MULTIPLE_MASTERS */ - /* FT_FACE_FLAG_VARIATION */ - /* FT_FACE_FLAG_GLYPH_NAMES */ - /* FT_FACE_FLAG_EXTERNAL_STREAM */ - /* FT_FACE_FLAG_HINTER */ - /* */ - /* FT_HAS_HORIZONTAL */ - /* FT_HAS_VERTICAL */ - /* FT_HAS_KERNING */ - /* FT_HAS_FIXED_SIZES */ - /* FT_HAS_GLYPH_NAMES */ - /* FT_HAS_COLOR */ - /* FT_HAS_MULTIPLE_MASTERS */ - /* */ - /* FT_IS_SFNT */ - /* FT_IS_SCALABLE */ - /* FT_IS_FIXED_WIDTH */ - /* FT_IS_CID_KEYED */ - /* FT_IS_TRICKY */ - /* FT_IS_NAMED_INSTANCE */ - /* FT_IS_VARIATION */ - /* */ - /* FT_STYLE_FLAG_BOLD */ - /* FT_STYLE_FLAG_ITALIC */ - /* */ - /* FT_SizeRec */ - /* FT_Size_Metrics */ - /* */ - /* FT_GlyphSlotRec */ - /* FT_Glyph_Metrics */ - /* FT_SubGlyph */ - /* */ - /* FT_Bitmap_Size */ - /* */ - /* FT_Init_FreeType */ - /* FT_Done_FreeType */ - /* */ - /* FT_New_Face */ - /* FT_Done_Face */ - /* FT_Reference_Face */ - /* FT_New_Memory_Face */ - /* FT_Face_Properties */ - /* FT_Open_Face */ - /* FT_Open_Args */ - /* FT_Parameter */ - /* FT_Attach_File */ - /* FT_Attach_Stream */ - /* */ - /* FT_Set_Char_Size */ - /* FT_Set_Pixel_Sizes */ - /* FT_Request_Size */ - /* FT_Select_Size */ - /* FT_Size_Request_Type */ - /* FT_Size_RequestRec */ - /* FT_Size_Request */ - /* FT_Set_Transform */ - /* FT_Load_Glyph */ - /* FT_Get_Char_Index */ - /* FT_Get_First_Char */ - /* FT_Get_Next_Char */ - /* FT_Get_Name_Index */ - /* FT_Load_Char */ - /* */ - /* FT_OPEN_MEMORY */ - /* FT_OPEN_STREAM */ - /* FT_OPEN_PATHNAME */ - /* FT_OPEN_DRIVER */ - /* FT_OPEN_PARAMS */ - /* */ - /* FT_LOAD_DEFAULT */ - /* FT_LOAD_RENDER */ - /* FT_LOAD_MONOCHROME */ - /* FT_LOAD_LINEAR_DESIGN */ - /* FT_LOAD_NO_SCALE */ - /* FT_LOAD_NO_HINTING */ - /* FT_LOAD_NO_BITMAP */ - /* FT_LOAD_NO_AUTOHINT */ - /* FT_LOAD_COLOR */ - /* */ - /* FT_LOAD_VERTICAL_LAYOUT */ - /* FT_LOAD_IGNORE_TRANSFORM */ - /* FT_LOAD_FORCE_AUTOHINT */ - /* FT_LOAD_NO_RECURSE */ - /* FT_LOAD_PEDANTIC */ - /* */ - /* FT_LOAD_TARGET_NORMAL */ - /* FT_LOAD_TARGET_LIGHT */ - /* FT_LOAD_TARGET_MONO */ - /* FT_LOAD_TARGET_LCD */ - /* FT_LOAD_TARGET_LCD_V */ - /* */ - /* FT_LOAD_TARGET_MODE */ - /* */ - /* FT_Render_Glyph */ - /* FT_Render_Mode */ - /* FT_Get_Kerning */ - /* FT_Kerning_Mode */ - /* FT_Get_Track_Kerning */ - /* FT_Get_Glyph_Name */ - /* FT_Get_Postscript_Name */ - /* */ - /* FT_CharMapRec */ - /* FT_Select_Charmap */ - /* FT_Set_Charmap */ - /* FT_Get_Charmap_Index */ - /* */ - /* FT_Get_FSType_Flags */ - /* FT_Get_SubGlyph_Info */ - /* */ - /* FT_Face_Internal */ - /* FT_Size_Internal */ - /* FT_Slot_Internal */ - /* */ - /* FT_FACE_FLAG_XXX */ - /* FT_STYLE_FLAG_XXX */ - /* FT_OPEN_XXX */ - /* FT_LOAD_XXX */ - /* FT_LOAD_TARGET_XXX */ - /* FT_SUBGLYPH_FLAG_XXX */ - /* FT_FSTYPE_XXX */ - /* */ - /* FT_HAS_FAST_GLYPHS */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * base_interface + * + * @title: + * Base Interface + * + * @abstract: + * The FreeType~2 base font interface. + * + * @description: + * This section describes the most important public high-level API + * functions of FreeType~2. + * + * @order: + * FT_Library + * FT_Face + * FT_Size + * FT_GlyphSlot + * FT_CharMap + * FT_Encoding + * FT_ENC_TAG + * + * FT_FaceRec + * + * FT_FACE_FLAG_SCALABLE + * FT_FACE_FLAG_FIXED_SIZES + * FT_FACE_FLAG_FIXED_WIDTH + * FT_FACE_FLAG_HORIZONTAL + * FT_FACE_FLAG_VERTICAL + * FT_FACE_FLAG_COLOR + * FT_FACE_FLAG_SFNT + * FT_FACE_FLAG_CID_KEYED + * FT_FACE_FLAG_TRICKY + * FT_FACE_FLAG_KERNING + * FT_FACE_FLAG_MULTIPLE_MASTERS + * FT_FACE_FLAG_VARIATION + * FT_FACE_FLAG_GLYPH_NAMES + * FT_FACE_FLAG_EXTERNAL_STREAM + * FT_FACE_FLAG_HINTER + * + * FT_HAS_HORIZONTAL + * FT_HAS_VERTICAL + * FT_HAS_KERNING + * FT_HAS_FIXED_SIZES + * FT_HAS_GLYPH_NAMES + * FT_HAS_COLOR + * FT_HAS_MULTIPLE_MASTERS + * + * FT_IS_SFNT + * FT_IS_SCALABLE + * FT_IS_FIXED_WIDTH + * FT_IS_CID_KEYED + * FT_IS_TRICKY + * FT_IS_NAMED_INSTANCE + * FT_IS_VARIATION + * + * FT_STYLE_FLAG_BOLD + * FT_STYLE_FLAG_ITALIC + * + * FT_SizeRec + * FT_Size_Metrics + * + * FT_GlyphSlotRec + * FT_Glyph_Metrics + * FT_SubGlyph + * + * FT_Bitmap_Size + * + * FT_Init_FreeType + * FT_Done_FreeType + * + * FT_New_Face + * FT_Done_Face + * FT_Reference_Face + * FT_New_Memory_Face + * FT_Face_Properties + * FT_Open_Face + * FT_Open_Args + * FT_Parameter + * FT_Attach_File + * FT_Attach_Stream + * + * FT_Set_Char_Size + * FT_Set_Pixel_Sizes + * FT_Request_Size + * FT_Select_Size + * FT_Size_Request_Type + * FT_Size_RequestRec + * FT_Size_Request + * FT_Set_Transform + * FT_Load_Glyph + * FT_Get_Char_Index + * FT_Get_First_Char + * FT_Get_Next_Char + * FT_Get_Name_Index + * FT_Load_Char + * + * FT_OPEN_MEMORY + * FT_OPEN_STREAM + * FT_OPEN_PATHNAME + * FT_OPEN_DRIVER + * FT_OPEN_PARAMS + * + * FT_LOAD_DEFAULT + * FT_LOAD_RENDER + * FT_LOAD_MONOCHROME + * FT_LOAD_LINEAR_DESIGN + * FT_LOAD_NO_SCALE + * FT_LOAD_NO_HINTING + * FT_LOAD_NO_BITMAP + * FT_LOAD_NO_AUTOHINT + * FT_LOAD_COLOR + * + * FT_LOAD_VERTICAL_LAYOUT + * FT_LOAD_IGNORE_TRANSFORM + * FT_LOAD_FORCE_AUTOHINT + * FT_LOAD_NO_RECURSE + * FT_LOAD_PEDANTIC + * + * FT_LOAD_TARGET_NORMAL + * FT_LOAD_TARGET_LIGHT + * FT_LOAD_TARGET_MONO + * FT_LOAD_TARGET_LCD + * FT_LOAD_TARGET_LCD_V + * + * FT_LOAD_TARGET_MODE + * + * FT_Render_Glyph + * FT_Render_Mode + * FT_Get_Kerning + * FT_Kerning_Mode + * FT_Get_Track_Kerning + * FT_Get_Glyph_Name + * FT_Get_Postscript_Name + * + * FT_CharMapRec + * FT_Select_Charmap + * FT_Set_Charmap + * FT_Get_Charmap_Index + * + * FT_Get_FSType_Flags + * FT_Get_SubGlyph_Info + * + * FT_Face_Internal + * FT_Size_Internal + * FT_Slot_Internal + * + * FT_FACE_FLAG_XXX + * FT_STYLE_FLAG_XXX + * FT_OPEN_XXX + * FT_LOAD_XXX + * FT_LOAD_TARGET_XXX + * FT_SUBGLYPH_FLAG_XXX + * FT_FSTYPE_XXX + * + * FT_HAS_FAST_GLYPHS + * + */ - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Glyph_Metrics */ - /* */ - /* <Description> */ - /* A structure to model the metrics of a single glyph. The values */ - /* are expressed in 26.6 fractional pixel format; if the flag */ - /* @FT_LOAD_NO_SCALE has been used while loading the glyph, values */ - /* are expressed in font units instead. */ - /* */ - /* <Fields> */ - /* width :: */ - /* The glyph's width. */ - /* */ - /* height :: */ - /* The glyph's height. */ - /* */ - /* horiBearingX :: */ - /* Left side bearing for horizontal layout. */ - /* */ - /* horiBearingY :: */ - /* Top side bearing for horizontal layout. */ - /* */ - /* horiAdvance :: */ - /* Advance width for horizontal layout. */ - /* */ - /* vertBearingX :: */ - /* Left side bearing for vertical layout. */ - /* */ - /* vertBearingY :: */ - /* Top side bearing for vertical layout. Larger positive values */ - /* mean further below the vertical glyph origin. */ - /* */ - /* vertAdvance :: */ - /* Advance height for vertical layout. Positive values mean the */ - /* glyph has a positive advance downward. */ - /* */ - /* <Note> */ - /* If not disabled with @FT_LOAD_NO_HINTING, the values represent */ - /* dimensions of the hinted glyph (in case hinting is applicable). */ - /* */ - /* Stroking a glyph with an outside border does not increase */ - /* `horiAdvance' or `vertAdvance'; you have to manually adjust these */ - /* values to account for the added width and height. */ - /* */ - /* FreeType doesn't use the `VORG' table data for CFF fonts because */ - /* it doesn't have an interface to quickly retrieve the glyph height. */ - /* The y~coordinate of the vertical origin can be simply computed as */ - /* `vertBearingY + height' after loading a glyph. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Glyph_Metrics + * + * @description: + * A structure to model the metrics of a single glyph. The values are + * expressed in 26.6 fractional pixel format; if the flag + * @FT_LOAD_NO_SCALE has been used while loading the glyph, values are + * expressed in font units instead. + * + * @fields: + * width :: + * The glyph's width. + * + * height :: + * The glyph's height. + * + * horiBearingX :: + * Left side bearing for horizontal layout. + * + * horiBearingY :: + * Top side bearing for horizontal layout. + * + * horiAdvance :: + * Advance width for horizontal layout. + * + * vertBearingX :: + * Left side bearing for vertical layout. + * + * vertBearingY :: + * Top side bearing for vertical layout. Larger positive values mean + * further below the vertical glyph origin. + * + * vertAdvance :: + * Advance height for vertical layout. Positive values mean the glyph + * has a positive advance downward. + * + * @note: + * If not disabled with @FT_LOAD_NO_HINTING, the values represent + * dimensions of the hinted glyph (in case hinting is applicable). + * + * Stroking a glyph with an outside border does not increase + * `horiAdvance` or `vertAdvance`; you have to manually adjust these + * values to account for the added width and height. + * + * FreeType doesn't use the 'VORG' table data for CFF fonts because it + * doesn't have an interface to quickly retrieve the glyph height. The + * y~coordinate of the vertical origin can be simply computed as + * `vertBearingY + height` after loading a glyph. + */ typedef struct FT_Glyph_Metrics_ { FT_Pos width; @@ -330,44 +329,45 @@ FT_BEGIN_HEADER } FT_Glyph_Metrics; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Bitmap_Size */ - /* */ - /* <Description> */ - /* This structure models the metrics of a bitmap strike (i.e., a set */ - /* of glyphs for a given point size and resolution) in a bitmap font. */ - /* It is used for the `available_sizes' field of @FT_Face. */ - /* */ - /* <Fields> */ - /* height :: The vertical distance, in pixels, between two */ - /* consecutive baselines. It is always positive. */ - /* */ - /* width :: The average width, in pixels, of all glyphs in the */ - /* strike. */ - /* */ - /* size :: The nominal size of the strike in 26.6 fractional */ - /* points. This field is not very useful. */ - /* */ - /* x_ppem :: The horizontal ppem (nominal width) in 26.6 fractional */ - /* pixels. */ - /* */ - /* y_ppem :: The vertical ppem (nominal height) in 26.6 fractional */ - /* pixels. */ - /* */ - /* <Note> */ - /* Windows FNT: */ - /* The nominal size given in a FNT font is not reliable. If the */ - /* driver finds it incorrect, it sets `size' to some calculated */ - /* values, and `x_ppem' and `y_ppem' to the pixel width and height */ - /* given in the font, respectively. */ - /* */ - /* TrueType embedded bitmaps: */ - /* `size', `width', and `height' values are not contained in the */ - /* bitmap strike itself. They are computed from the global font */ - /* parameters. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Bitmap_Size + * + * @description: + * This structure models the metrics of a bitmap strike (i.e., a set of + * glyphs for a given point size and resolution) in a bitmap font. It is + * used for the `available_sizes` field of @FT_Face. + * + * @fields: + * height :: + * The vertical distance, in pixels, between two consecutive baselines. + * It is always positive. + * + * width :: + * The average width, in pixels, of all glyphs in the strike. + * + * size :: + * The nominal size of the strike in 26.6 fractional points. This + * field is not very useful. + * + * x_ppem :: + * The horizontal ppem (nominal width) in 26.6 fractional pixels. + * + * y_ppem :: + * The vertical ppem (nominal height) in 26.6 fractional pixels. + * + * @note: + * Windows FNT: + * The nominal size given in a FNT font is not reliable. If the driver + * finds it incorrect, it sets `size` to some calculated values, and + * `x_ppem` and `y_ppem` to the pixel width and height given in the + * font, respectively. + * + * TrueType embedded bitmaps: + * `size`, `width`, and `height` values are not contained in the bitmap + * strike itself. They are computed from the global font parameters. + */ typedef struct FT_Bitmap_Size_ { FT_Short height; @@ -389,225 +389,218 @@ FT_BEGIN_HEADER /*************************************************************************/ /*************************************************************************/ - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Library */ - /* */ - /* <Description> */ - /* A handle to a FreeType library instance. Each `library' is */ - /* completely independent from the others; it is the `root' of a set */ - /* of objects like fonts, faces, sizes, etc. */ - /* */ - /* It also embeds a memory manager (see @FT_Memory), as well as a */ - /* scan-line converter object (see @FT_Raster). */ - /* */ - /* In multi-threaded applications it is easiest to use one */ - /* `FT_Library' object per thread. In case this is too cumbersome, */ - /* a single `FT_Library' object across threads is possible also */ - /* (since FreeType version 2.5.6), as long as a mutex lock is used */ - /* around @FT_New_Face and @FT_Done_Face. */ - /* */ - /* <Note> */ - /* Library objects are normally created by @FT_Init_FreeType, and */ - /* destroyed with @FT_Done_FreeType. If you need reference-counting */ - /* (cf. @FT_Reference_Library), use @FT_New_Library and */ - /* @FT_Done_Library. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Library + * + * @description: + * A handle to a FreeType library instance. Each 'library' is completely + * independent from the others; it is the 'root' of a set of objects like + * fonts, faces, sizes, etc. + * + * It also embeds a memory manager (see @FT_Memory), as well as a + * scan-line converter object (see @FT_Raster). + * + * [Since 2.5.6] In multi-threaded applications it is easiest to use one + * `FT_Library` object per thread. In case this is too cumbersome, a + * single `FT_Library` object across threads is possible also, as long as + * a mutex lock is used around @FT_New_Face and @FT_Done_Face. + * + * @note: + * Library objects are normally created by @FT_Init_FreeType, and + * destroyed with @FT_Done_FreeType. If you need reference-counting + * (cf. @FT_Reference_Library), use @FT_New_Library and @FT_Done_Library. + */ typedef struct FT_LibraryRec_ *FT_Library; - /*************************************************************************/ - /* */ - /* <Section> */ - /* module_management */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * module_management + * + */ - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Module */ - /* */ - /* <Description> */ - /* A handle to a given FreeType module object. A module can be a */ - /* font driver, a renderer, or anything else that provides services */ - /* to the former. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Module + * + * @description: + * A handle to a given FreeType module object. A module can be a font + * driver, a renderer, or anything else that provides services to the + * former. + */ typedef struct FT_ModuleRec_* FT_Module; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Driver */ - /* */ - /* <Description> */ - /* A handle to a given FreeType font driver object. A font driver */ - /* is a module capable of creating faces from font files. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Driver + * + * @description: + * A handle to a given FreeType font driver object. A font driver is a + * module capable of creating faces from font files. + */ typedef struct FT_DriverRec_* FT_Driver; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Renderer */ - /* */ - /* <Description> */ - /* A handle to a given FreeType renderer. A renderer is a module in */ - /* charge of converting a glyph's outline image to a bitmap. It */ - /* supports a single glyph image format, and one or more target */ - /* surface depths. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Renderer + * + * @description: + * A handle to a given FreeType renderer. A renderer is a module in + * charge of converting a glyph's outline image to a bitmap. It supports + * a single glyph image format, and one or more target surface depths. + */ typedef struct FT_RendererRec_* FT_Renderer; - /*************************************************************************/ - /* */ - /* <Section> */ - /* base_interface */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * base_interface + * + */ - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Face */ - /* */ - /* <Description> */ - /* A handle to a typographic face object. A face object models a */ - /* given typeface, in a given style. */ - /* */ - /* <Note> */ - /* A face object also owns a single @FT_GlyphSlot object, as well */ - /* as one or more @FT_Size objects. */ - /* */ - /* Use @FT_New_Face or @FT_Open_Face to create a new face object from */ - /* a given filepath or a custom input stream. */ - /* */ - /* Use @FT_Done_Face to destroy it (along with its slot and sizes). */ - /* */ - /* An `FT_Face' object can only be safely used from one thread at a */ - /* time. Similarly, creation and destruction of `FT_Face' with the */ - /* same @FT_Library object can only be done from one thread at a */ - /* time. On the other hand, functions like @FT_Load_Glyph and its */ - /* siblings are thread-safe and do not need the lock to be held as */ - /* long as the same `FT_Face' object is not used from multiple */ - /* threads at the same time. */ - /* */ - /* <Also> */ - /* See @FT_FaceRec for the publicly accessible fields of a given face */ - /* object. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Face + * + * @description: + * A handle to a typographic face object. A face object models a given + * typeface, in a given style. + * + * @note: + * A face object also owns a single @FT_GlyphSlot object, as well as one + * or more @FT_Size objects. + * + * Use @FT_New_Face or @FT_Open_Face to create a new face object from a + * given filepath or a custom input stream. + * + * Use @FT_Done_Face to destroy it (along with its slot and sizes). + * + * An `FT_Face` object can only be safely used from one thread at a time. + * Similarly, creation and destruction of `FT_Face` with the same + * @FT_Library object can only be done from one thread at a time. On the + * other hand, functions like @FT_Load_Glyph and its siblings are + * thread-safe and do not need the lock to be held as long as the same + * `FT_Face` object is not used from multiple threads at the same time. + * + * @also: + * See @FT_FaceRec for the publicly accessible fields of a given face + * object. + */ typedef struct FT_FaceRec_* FT_Face; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Size */ - /* */ - /* <Description> */ - /* A handle to an object that models a face scaled to a given */ - /* character size. */ - /* */ - /* <Note> */ - /* An @FT_Face has one _active_ @FT_Size object that is used by */ - /* functions like @FT_Load_Glyph to determine the scaling */ - /* transformation that in turn is used to load and hint glyphs and */ - /* metrics. */ - /* */ - /* You can use @FT_Set_Char_Size, @FT_Set_Pixel_Sizes, */ - /* @FT_Request_Size or even @FT_Select_Size to change the content */ - /* (i.e., the scaling values) of the active @FT_Size. */ - /* */ - /* You can use @FT_New_Size to create additional size objects for a */ - /* given @FT_Face, but they won't be used by other functions until */ - /* you activate it through @FT_Activate_Size. Only one size can be */ - /* activated at any given time per face. */ - /* */ - /* <Also> */ - /* See @FT_SizeRec for the publicly accessible fields of a given size */ - /* object. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Size + * + * @description: + * A handle to an object that models a face scaled to a given character + * size. + * + * @note: + * An @FT_Face has one _active_ @FT_Size object that is used by functions + * like @FT_Load_Glyph to determine the scaling transformation that in + * turn is used to load and hint glyphs and metrics. + * + * You can use @FT_Set_Char_Size, @FT_Set_Pixel_Sizes, @FT_Request_Size + * or even @FT_Select_Size to change the content (i.e., the scaling + * values) of the active @FT_Size. + * + * You can use @FT_New_Size to create additional size objects for a given + * @FT_Face, but they won't be used by other functions until you activate + * it through @FT_Activate_Size. Only one size can be activated at any + * given time per face. + * + * @also: + * See @FT_SizeRec for the publicly accessible fields of a given size + * object. + */ typedef struct FT_SizeRec_* FT_Size; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_GlyphSlot */ - /* */ - /* <Description> */ - /* A handle to a given `glyph slot'. A slot is a container that can */ - /* hold any of the glyphs contained in its parent face. */ - /* */ - /* In other words, each time you call @FT_Load_Glyph or */ - /* @FT_Load_Char, the slot's content is erased by the new glyph data, */ - /* i.e., the glyph's metrics, its image (bitmap or outline), and */ - /* other control information. */ - /* */ - /* <Also> */ - /* See @FT_GlyphSlotRec for the publicly accessible glyph fields. */ - /* */ + /************************************************************************** + * + * @type: + * FT_GlyphSlot + * + * @description: + * A handle to a given 'glyph slot'. A slot is a container that can hold + * any of the glyphs contained in its parent face. + * + * In other words, each time you call @FT_Load_Glyph or @FT_Load_Char, + * the slot's content is erased by the new glyph data, i.e., the glyph's + * metrics, its image (bitmap or outline), and other control information. + * + * @also: + * See @FT_GlyphSlotRec for the publicly accessible glyph fields. + */ typedef struct FT_GlyphSlotRec_* FT_GlyphSlot; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_CharMap */ - /* */ - /* <Description> */ - /* A handle to a character map (usually abbreviated to `charmap'). A */ - /* charmap is used to translate character codes in a given encoding */ - /* into glyph indexes for its parent's face. Some font formats may */ - /* provide several charmaps per font. */ - /* */ - /* Each face object owns zero or more charmaps, but only one of them */ - /* can be `active', providing the data used by @FT_Get_Char_Index or */ - /* @FT_Load_Char. */ - /* */ - /* The list of available charmaps in a face is available through the */ - /* `face->num_charmaps' and `face->charmaps' fields of @FT_FaceRec. */ - /* */ - /* The currently active charmap is available as `face->charmap'. */ - /* You should call @FT_Set_Charmap to change it. */ - /* */ - /* <Note> */ - /* When a new face is created (either through @FT_New_Face or */ - /* @FT_Open_Face), the library looks for a Unicode charmap within */ - /* the list and automatically activates it. If there is no Unicode */ - /* charmap, FreeType doesn't set an `active' charmap. */ - /* */ - /* <Also> */ - /* See @FT_CharMapRec for the publicly accessible fields of a given */ - /* character map. */ - /* */ + /************************************************************************** + * + * @type: + * FT_CharMap + * + * @description: + * A handle to a character map (usually abbreviated to 'charmap'). A + * charmap is used to translate character codes in a given encoding into + * glyph indexes for its parent's face. Some font formats may provide + * several charmaps per font. + * + * Each face object owns zero or more charmaps, but only one of them can + * be 'active', providing the data used by @FT_Get_Char_Index or + * @FT_Load_Char. + * + * The list of available charmaps in a face is available through the + * `face->num_charmaps` and `face->charmaps` fields of @FT_FaceRec. + * + * The currently active charmap is available as `face->charmap`. You + * should call @FT_Set_Charmap to change it. + * + * @note: + * When a new face is created (either through @FT_New_Face or + * @FT_Open_Face), the library looks for a Unicode charmap within the + * list and automatically activates it. If there is no Unicode charmap, + * FreeType doesn't set an 'active' charmap. + * + * @also: + * See @FT_CharMapRec for the publicly accessible fields of a given + * character map. + */ typedef struct FT_CharMapRec_* FT_CharMap; - /*************************************************************************/ - /* */ - /* <Macro> */ - /* FT_ENC_TAG */ - /* */ - /* <Description> */ - /* This macro converts four-letter tags into an unsigned long. It is */ - /* used to define `encoding' identifiers (see @FT_Encoding). */ - /* */ - /* <Note> */ - /* Since many 16-bit compilers don't like 32-bit enumerations, you */ - /* should redefine this macro in case of problems to something like */ - /* this: */ - /* */ - /* { */ - /* #define FT_ENC_TAG( value, a, b, c, d ) value */ - /* } */ - /* */ - /* to get a simple enumeration without assigning special numbers. */ - /* */ + /************************************************************************** + * + * @macro: + * FT_ENC_TAG + * + * @description: + * This macro converts four-letter tags into an unsigned long. It is + * used to define 'encoding' identifiers (see @FT_Encoding). + * + * @note: + * Since many 16-bit compilers don't like 32-bit enumerations, you should + * redefine this macro in case of problems to something like this: + * + * ``` + * #define FT_ENC_TAG( value, a, b, c, d ) value + * ``` + * + * to get a simple enumeration without assigning special numbers. + */ #ifndef FT_ENC_TAG #define FT_ENC_TAG( value, a, b, c, d ) \ @@ -619,150 +612,147 @@ FT_BEGIN_HEADER #endif /* FT_ENC_TAG */ - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_Encoding */ - /* */ - /* <Description> */ - /* An enumeration to specify character sets supported by charmaps. */ - /* Used in the @FT_Select_Charmap API function. */ - /* */ - /* <Note> */ - /* Despite the name, this enumeration lists specific character */ - /* repertories (i.e., charsets), and not text encoding methods (e.g., */ - /* UTF-8, UTF-16, etc.). */ - /* */ - /* Other encodings might be defined in the future. */ - /* */ - /* <Values> */ - /* FT_ENCODING_NONE :: */ - /* The encoding value~0 is reserved. */ - /* */ - /* FT_ENCODING_UNICODE :: */ - /* The Unicode character set. This value covers all versions of */ - /* the Unicode repertoire, including ASCII and Latin-1. Most fonts */ - /* include a Unicode charmap, but not all of them. */ - /* */ - /* For example, if you want to access Unicode value U+1F028 (and */ - /* the font contains it), use value 0x1F028 as the input value for */ - /* @FT_Get_Char_Index. */ - /* */ - /* FT_ENCODING_MS_SYMBOL :: */ - /* Microsoft Symbol encoding, used to encode mathematical symbols */ - /* and wingdings. For more information, see */ - /* `https://www.microsoft.com/typography/otspec/recom.htm', */ - /* `http://www.kostis.net/charsets/symbol.htm', and */ - /* `http://www.kostis.net/charsets/wingding.htm'. */ - /* */ - /* This encoding uses character codes from the PUA (Private Unicode */ - /* Area) in the range U+F020-U+F0FF. */ - /* */ - /* FT_ENCODING_SJIS :: */ - /* Shift JIS encoding for Japanese. More info at */ - /* `https://en.wikipedia.org/wiki/Shift_JIS'. See note on */ - /* multi-byte encodings below. */ - /* */ - /* FT_ENCODING_PRC :: */ - /* Corresponds to encoding systems mainly for Simplified Chinese as */ - /* used in People's Republic of China (PRC). The encoding layout */ - /* is based on GB~2312 and its supersets GBK and GB~18030. */ - /* */ - /* FT_ENCODING_BIG5 :: */ - /* Corresponds to an encoding system for Traditional Chinese as */ - /* used in Taiwan and Hong Kong. */ - /* */ - /* FT_ENCODING_WANSUNG :: */ - /* Corresponds to the Korean encoding system known as Extended */ - /* Wansung (MS Windows code page 949). */ - /* For more information see */ - /* `https://www.unicode.org/Public/MAPPINGS/VENDORS/MICSFT/WindowsBestFit/bestfit949.txt'. */ - /* */ - /* FT_ENCODING_JOHAB :: */ - /* The Korean standard character set (KS~C 5601-1992), which */ - /* corresponds to MS Windows code page 1361. This character set */ - /* includes all possible Hangul character combinations. */ - /* */ - /* FT_ENCODING_ADOBE_LATIN_1 :: */ - /* Corresponds to a Latin-1 encoding as defined in a Type~1 */ - /* PostScript font. It is limited to 256 character codes. */ - /* */ - /* FT_ENCODING_ADOBE_STANDARD :: */ - /* Adobe Standard encoding, as found in Type~1, CFF, and */ - /* OpenType/CFF fonts. It is limited to 256 character codes. */ - /* */ - /* FT_ENCODING_ADOBE_EXPERT :: */ - /* Adobe Expert encoding, as found in Type~1, CFF, and OpenType/CFF */ - /* fonts. It is limited to 256 character codes. */ - /* */ - /* FT_ENCODING_ADOBE_CUSTOM :: */ - /* Corresponds to a custom encoding, as found in Type~1, CFF, and */ - /* OpenType/CFF fonts. It is limited to 256 character codes. */ - /* */ - /* FT_ENCODING_APPLE_ROMAN :: */ - /* Apple roman encoding. Many TrueType and OpenType fonts contain */ - /* a charmap for this 8-bit encoding, since older versions of Mac */ - /* OS are able to use it. */ - /* */ - /* FT_ENCODING_OLD_LATIN_2 :: */ - /* This value is deprecated and was neither used nor reported by */ - /* FreeType. Don't use or test for it. */ - /* */ - /* FT_ENCODING_MS_SJIS :: */ - /* Same as FT_ENCODING_SJIS. Deprecated. */ - /* */ - /* FT_ENCODING_MS_GB2312 :: */ - /* Same as FT_ENCODING_PRC. Deprecated. */ - /* */ - /* FT_ENCODING_MS_BIG5 :: */ - /* Same as FT_ENCODING_BIG5. Deprecated. */ - /* */ - /* FT_ENCODING_MS_WANSUNG :: */ - /* Same as FT_ENCODING_WANSUNG. Deprecated. */ - /* */ - /* FT_ENCODING_MS_JOHAB :: */ - /* Same as FT_ENCODING_JOHAB. Deprecated. */ - /* */ - /* <Note> */ - /* By default, FreeType enables a Unicode charmap and tags it with */ - /* FT_ENCODING_UNICODE when it is either provided or can be generated */ - /* from PostScript glyph name dictionaries in the font file. */ - /* All other encodings are considered legacy and tagged only if */ - /* explicitly defined in the font file. Otherwise, FT_ENCODING_NONE */ - /* is used. */ - /* */ - /* FT_ENCODING_NONE is set by the BDF and PCF drivers if the charmap */ - /* is neither Unicode nor ISO-8859-1 (otherwise it is set to */ - /* FT_ENCODING_UNICODE). Use @FT_Get_BDF_Charset_ID to find out */ - /* which encoding is really present. If, for example, the */ - /* `cs_registry' field is `KOI8' and the `cs_encoding' field is `R', */ - /* the font is encoded in KOI8-R. */ - /* */ - /* FT_ENCODING_NONE is always set (with a single exception) by the */ - /* winfonts driver. Use @FT_Get_WinFNT_Header and examine the */ - /* `charset' field of the @FT_WinFNT_HeaderRec structure to find out */ - /* which encoding is really present. For example, */ - /* @FT_WinFNT_ID_CP1251 (204) means Windows code page 1251 (for */ - /* Russian). */ - /* */ - /* FT_ENCODING_NONE is set if `platform_id' is @TT_PLATFORM_MACINTOSH */ - /* and `encoding_id' is not `TT_MAC_ID_ROMAN' (otherwise it is set to */ - /* FT_ENCODING_APPLE_ROMAN). */ - /* */ - /* If `platform_id' is @TT_PLATFORM_MACINTOSH, use the function */ - /* @FT_Get_CMap_Language_ID to query the Mac language ID that may */ - /* be needed to be able to distinguish Apple encoding variants. See */ - /* */ - /* https://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/Readme.txt */ - /* */ - /* to get an idea how to do that. Basically, if the language ID */ - /* is~0, don't use it, otherwise subtract 1 from the language ID. */ - /* Then examine `encoding_id'. If, for example, `encoding_id' is */ - /* `TT_MAC_ID_ROMAN' and the language ID (minus~1) is */ - /* `TT_MAC_LANGID_GREEK', it is the Greek encoding, not Roman. */ - /* `TT_MAC_ID_ARABIC' with `TT_MAC_LANGID_FARSI' means the Farsi */ - /* variant the Arabic encoding. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_Encoding + * + * @description: + * An enumeration to specify character sets supported by charmaps. Used + * in the @FT_Select_Charmap API function. + * + * @note: + * Despite the name, this enumeration lists specific character + * repertories (i.e., charsets), and not text encoding methods (e.g., + * UTF-8, UTF-16, etc.). + * + * Other encodings might be defined in the future. + * + * @values: + * FT_ENCODING_NONE :: + * The encoding value~0 is reserved for all formats except BDF, PCF, + * and Windows FNT; see below for more information. + * + * FT_ENCODING_UNICODE :: + * The Unicode character set. This value covers all versions of the + * Unicode repertoire, including ASCII and Latin-1. Most fonts include + * a Unicode charmap, but not all of them. + * + * For example, if you want to access Unicode value U+1F028 (and the + * font contains it), use value 0x1F028 as the input value for + * @FT_Get_Char_Index. + * + * FT_ENCODING_MS_SYMBOL :: + * Microsoft Symbol encoding, used to encode mathematical symbols and + * wingdings. For more information, see + * 'https://www.microsoft.com/typography/otspec/recom.htm', + * 'http://www.kostis.net/charsets/symbol.htm', and + * 'http://www.kostis.net/charsets/wingding.htm'. + * + * This encoding uses character codes from the PUA (Private Unicode + * Area) in the range U+F020-U+F0FF. + * + * FT_ENCODING_SJIS :: + * Shift JIS encoding for Japanese. More info at + * 'https://en.wikipedia.org/wiki/Shift_JIS'. See note on multi-byte + * encodings below. + * + * FT_ENCODING_PRC :: + * Corresponds to encoding systems mainly for Simplified Chinese as + * used in People's Republic of China (PRC). The encoding layout is + * based on GB~2312 and its supersets GBK and GB~18030. + * + * FT_ENCODING_BIG5 :: + * Corresponds to an encoding system for Traditional Chinese as used in + * Taiwan and Hong Kong. + * + * FT_ENCODING_WANSUNG :: + * Corresponds to the Korean encoding system known as Extended Wansung + * (MS Windows code page 949). For more information see + * 'https://www.unicode.org/Public/MAPPINGS/VENDORS/MICSFT/WindowsBestFit/bestfit949.txt'. + * + * FT_ENCODING_JOHAB :: + * The Korean standard character set (KS~C 5601-1992), which + * corresponds to MS Windows code page 1361. This character set + * includes all possible Hangul character combinations. + * + * FT_ENCODING_ADOBE_LATIN_1 :: + * Corresponds to a Latin-1 encoding as defined in a Type~1 PostScript + * font. It is limited to 256 character codes. + * + * FT_ENCODING_ADOBE_STANDARD :: + * Adobe Standard encoding, as found in Type~1, CFF, and OpenType/CFF + * fonts. It is limited to 256 character codes. + * + * FT_ENCODING_ADOBE_EXPERT :: + * Adobe Expert encoding, as found in Type~1, CFF, and OpenType/CFF + * fonts. It is limited to 256 character codes. + * + * FT_ENCODING_ADOBE_CUSTOM :: + * Corresponds to a custom encoding, as found in Type~1, CFF, and + * OpenType/CFF fonts. It is limited to 256 character codes. + * + * FT_ENCODING_APPLE_ROMAN :: + * Apple roman encoding. Many TrueType and OpenType fonts contain a + * charmap for this 8-bit encoding, since older versions of Mac OS are + * able to use it. + * + * FT_ENCODING_OLD_LATIN_2 :: + * This value is deprecated and was neither used nor reported by + * FreeType. Don't use or test for it. + * + * FT_ENCODING_MS_SJIS :: + * Same as FT_ENCODING_SJIS. Deprecated. + * + * FT_ENCODING_MS_GB2312 :: + * Same as FT_ENCODING_PRC. Deprecated. + * + * FT_ENCODING_MS_BIG5 :: + * Same as FT_ENCODING_BIG5. Deprecated. + * + * FT_ENCODING_MS_WANSUNG :: + * Same as FT_ENCODING_WANSUNG. Deprecated. + * + * FT_ENCODING_MS_JOHAB :: + * Same as FT_ENCODING_JOHAB. Deprecated. + * + * @note: + * By default, FreeType enables a Unicode charmap and tags it with + * `FT_ENCODING_UNICODE` when it is either provided or can be generated + * from PostScript glyph name dictionaries in the font file. All other + * encodings are considered legacy and tagged only if explicitly defined + * in the font file. Otherwise, `FT_ENCODING_NONE` is used. + * + * `FT_ENCODING_NONE` is set by the BDF and PCF drivers if the charmap is + * neither Unicode nor ISO-8859-1 (otherwise it is set to + * `FT_ENCODING_UNICODE`). Use @FT_Get_BDF_Charset_ID to find out which + * encoding is really present. If, for example, the `cs_registry` field + * is 'KOI8' and the `cs_encoding` field is 'R', the font is encoded in + * KOI8-R. + * + * `FT_ENCODING_NONE` is always set (with a single exception) by the + * winfonts driver. Use @FT_Get_WinFNT_Header and examine the `charset` + * field of the @FT_WinFNT_HeaderRec structure to find out which encoding + * is really present. For example, @FT_WinFNT_ID_CP1251 (204) means + * Windows code page 1251 (for Russian). + * + * `FT_ENCODING_NONE` is set if `platform_id` is @TT_PLATFORM_MACINTOSH + * and `encoding_id` is not `TT_MAC_ID_ROMAN` (otherwise it is set to + * `FT_ENCODING_APPLE_ROMAN`). + * + * If `platform_id` is @TT_PLATFORM_MACINTOSH, use the function + * @FT_Get_CMap_Language_ID to query the Mac language ID that may be + * needed to be able to distinguish Apple encoding variants. See + * + * https://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/Readme.txt + * + * to get an idea how to do that. Basically, if the language ID is~0, + * don't use it, otherwise subtract 1 from the language ID. Then examine + * `encoding_id`. If, for example, `encoding_id` is `TT_MAC_ID_ROMAN` + * and the language ID (minus~1) is `TT_MAC_LANGID_GREEK`, it is the + * Greek encoding, not Roman. `TT_MAC_ID_ARABIC` with + * `TT_MAC_LANGID_FARSI` means the Farsi variant the Arabic encoding. + */ typedef enum FT_Encoding_ { FT_ENC_TAG( FT_ENCODING_NONE, 0, 0, 0, 0 ), @@ -796,7 +786,7 @@ FT_BEGIN_HEADER } FT_Encoding; - /* these constants are deprecated; use the corresponding `FT_Encoding' */ + /* these constants are deprecated; use the corresponding `FT_Encoding` */ /* values instead */ #define ft_encoding_none FT_ENCODING_NONE #define ft_encoding_unicode FT_ENCODING_UNICODE @@ -815,29 +805,31 @@ FT_BEGIN_HEADER #define ft_encoding_apple_roman FT_ENCODING_APPLE_ROMAN - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_CharMapRec */ - /* */ - /* <Description> */ - /* The base charmap structure. */ - /* */ - /* <Fields> */ - /* face :: A handle to the parent face object. */ - /* */ - /* encoding :: An @FT_Encoding tag identifying the charmap. Use */ - /* this with @FT_Select_Charmap. */ - /* */ - /* platform_id :: An ID number describing the platform for the */ - /* following encoding ID. This comes directly from */ - /* the TrueType specification and gets emulated for */ - /* other formats. */ - /* */ - /* encoding_id :: A platform specific encoding number. This also */ - /* comes from the TrueType specification and gets */ - /* emulated similarly. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_CharMapRec + * + * @description: + * The base charmap structure. + * + * @fields: + * face :: + * A handle to the parent face object. + * + * encoding :: + * An @FT_Encoding tag identifying the charmap. Use this with + * @FT_Select_Charmap. + * + * platform_id :: + * An ID number describing the platform for the following encoding ID. + * This comes directly from the TrueType specification and gets + * emulated for other formats. + * + * encoding_id :: + * A platform-specific encoding number. This also comes from the + * TrueType specification and gets emulated similarly. + */ typedef struct FT_CharMapRec_ { FT_Face face; @@ -857,215 +849,195 @@ FT_BEGIN_HEADER /*************************************************************************/ - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Face_Internal */ - /* */ - /* <Description> */ - /* An opaque handle to an `FT_Face_InternalRec' structure that models */ - /* the private data of a given @FT_Face object. */ - /* */ - /* This structure might change between releases of FreeType~2 and is */ - /* not generally available to client applications. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Face_Internal + * + * @description: + * An opaque handle to an `FT_Face_InternalRec` structure that models the + * private data of a given @FT_Face object. + * + * This structure might change between releases of FreeType~2 and is not + * generally available to client applications. + */ typedef struct FT_Face_InternalRec_* FT_Face_Internal; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_FaceRec */ - /* */ - /* <Description> */ - /* FreeType root face class structure. A face object models a */ - /* typeface in a font file. */ - /* */ - /* <Fields> */ - /* num_faces :: The number of faces in the font file. Some */ - /* font formats can have multiple faces in */ - /* a single font file. */ - /* */ - /* face_index :: This field holds two different values. */ - /* Bits 0-15 are the index of the face in the */ - /* font file (starting with value~0). They */ - /* are set to~0 if there is only one face in */ - /* the font file. */ - /* */ - /* [Since 2.6.1] Bits 16-30 are relevant to GX */ - /* and OpenType variation fonts only, holding */ - /* the named instance index for the current */ - /* face index (starting with value~1; value~0 */ - /* indicates font access without a named */ - /* instance). For non-variation fonts, bits */ - /* 16-30 are ignored. If we have the third */ - /* named instance of face~4, say, `face_index' */ - /* is set to 0x00030004. */ - /* */ - /* Bit 31 is always zero (this is, */ - /* `face_index' is always a positive value). */ - /* */ - /* [Since 2.9] Changing the design coordinates */ - /* with @FT_Set_Var_Design_Coordinates or */ - /* @FT_Set_Var_Blend_Coordinates does not */ - /* influence the named instance index value */ - /* (only @FT_Set_Named_Instance does that). */ - /* */ - /* face_flags :: A set of bit flags that give important */ - /* information about the face; see */ - /* @FT_FACE_FLAG_XXX for the details. */ - /* */ - /* style_flags :: The lower 16~bits contain a set of bit */ - /* flags indicating the style of the face; see */ - /* @FT_STYLE_FLAG_XXX for the details. */ - /* */ - /* [Since 2.6.1] Bits 16-30 hold the number */ - /* of named instances available for the */ - /* current face if we have a GX or OpenType */ - /* variation (sub)font. Bit 31 is always zero */ - /* (this is, `style_flags' is always a */ - /* positive value). Note that a variation */ - /* font has always at least one named */ - /* instance, namely the default instance. */ - /* */ - /* num_glyphs :: The number of glyphs in the face. If the */ - /* face is scalable and has sbits (see */ - /* `num_fixed_sizes'), it is set to the number */ - /* of outline glyphs. */ - /* */ - /* For CID-keyed fonts (not in an SFNT */ - /* wrapper) this value gives the highest CID */ - /* used in the font. */ - /* */ - /* family_name :: The face's family name. This is an ASCII */ - /* string, usually in English, that describes */ - /* the typeface's family (like `Times New */ - /* Roman', `Bodoni', `Garamond', etc). This */ - /* is a least common denominator used to list */ - /* fonts. Some formats (TrueType & OpenType) */ - /* provide localized and Unicode versions of */ - /* this string. Applications should use the */ - /* format specific interface to access them. */ - /* Can be NULL (e.g., in fonts embedded in a */ - /* PDF file). */ - /* */ - /* In case the font doesn't provide a specific */ - /* family name entry, FreeType tries to */ - /* synthesize one, deriving it from other name */ - /* entries. */ - /* */ - /* style_name :: The face's style name. This is an ASCII */ - /* string, usually in English, that describes */ - /* the typeface's style (like `Italic', */ - /* `Bold', `Condensed', etc). Not all font */ - /* formats provide a style name, so this field */ - /* is optional, and can be set to NULL. As */ - /* for `family_name', some formats provide */ - /* localized and Unicode versions of this */ - /* string. Applications should use the format */ - /* specific interface to access them. */ - /* */ - /* num_fixed_sizes :: The number of bitmap strikes in the face. */ - /* Even if the face is scalable, there might */ - /* still be bitmap strikes, which are called */ - /* `sbits' in that case. */ - /* */ - /* available_sizes :: An array of @FT_Bitmap_Size for all bitmap */ - /* strikes in the face. It is set to NULL if */ - /* there is no bitmap strike. */ - /* */ - /* Note that FreeType tries to sanitize the */ - /* strike data since they are sometimes sloppy */ - /* or incorrect, but this can easily fail. */ - /* */ - /* num_charmaps :: The number of charmaps in the face. */ - /* */ - /* charmaps :: An array of the charmaps of the face. */ - /* */ - /* generic :: A field reserved for client uses. See the */ - /* @FT_Generic type description. */ - /* */ - /* bbox :: The font bounding box. Coordinates are */ - /* expressed in font units (see */ - /* `units_per_EM'). The box is large enough */ - /* to contain any glyph from the font. Thus, */ - /* `bbox.yMax' can be seen as the `maximum */ - /* ascender', and `bbox.yMin' as the `minimum */ - /* descender'. Only relevant for scalable */ - /* formats. */ - /* */ - /* Note that the bounding box might be off by */ - /* (at least) one pixel for hinted fonts. See */ - /* @FT_Size_Metrics for further discussion. */ - /* */ - /* units_per_EM :: The number of font units per EM square for */ - /* this face. This is typically 2048 for */ - /* TrueType fonts, and 1000 for Type~1 fonts. */ - /* Only relevant for scalable formats. */ - /* */ - /* ascender :: The typographic ascender of the face, */ - /* expressed in font units. For font formats */ - /* not having this information, it is set to */ - /* `bbox.yMax'. Only relevant for scalable */ - /* formats. */ - /* */ - /* descender :: The typographic descender of the face, */ - /* expressed in font units. For font formats */ - /* not having this information, it is set to */ - /* `bbox.yMin'. Note that this field is */ - /* negative for values below the baseline. */ - /* Only relevant for scalable formats. */ - /* */ - /* height :: This value is the vertical distance */ - /* between two consecutive baselines, */ - /* expressed in font units. It is always */ - /* positive. Only relevant for scalable */ - /* formats. */ - /* */ - /* If you want the global glyph height, use */ - /* `ascender - descender'. */ - /* */ - /* max_advance_width :: The maximum advance width, in font units, */ - /* for all glyphs in this face. This can be */ - /* used to make word wrapping computations */ - /* faster. Only relevant for scalable */ - /* formats. */ - /* */ - /* max_advance_height :: The maximum advance height, in font units, */ - /* for all glyphs in this face. This is only */ - /* relevant for vertical layouts, and is set */ - /* to `height' for fonts that do not provide */ - /* vertical metrics. Only relevant for */ - /* scalable formats. */ - /* */ - /* underline_position :: The position, in font units, of the */ - /* underline line for this face. It is the */ - /* center of the underlining stem. Only */ - /* relevant for scalable formats. */ - /* */ - /* underline_thickness :: The thickness, in font units, of the */ - /* underline for this face. Only relevant for */ - /* scalable formats. */ - /* */ - /* glyph :: The face's associated glyph slot(s). */ - /* */ - /* size :: The current active size for this face. */ - /* */ - /* charmap :: The current active charmap for this face. */ - /* */ - /* <Note> */ - /* Fields may be changed after a call to @FT_Attach_File or */ - /* @FT_Attach_Stream. */ - /* */ - /* For an OpenType variation font, the values of the following fields */ - /* can change after a call to @FT_Set_Var_Design_Coordinates (and */ - /* friends) if the font contains an `MVAR' table: `ascender', */ - /* `descender', `height', `underline_position', and */ - /* `underline_thickness'. */ - /* */ - /* Especially for TrueType fonts see also the documentation for */ - /* @FT_Size_Metrics. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_FaceRec + * + * @description: + * FreeType root face class structure. A face object models a typeface + * in a font file. + * + * @fields: + * num_faces :: + * The number of faces in the font file. Some font formats can have + * multiple faces in a single font file. + * + * face_index :: + * This field holds two different values. Bits 0-15 are the index of + * the face in the font file (starting with value~0). They are set + * to~0 if there is only one face in the font file. + * + * [Since 2.6.1] Bits 16-30 are relevant to GX and OpenType variation + * fonts only, holding the named instance index for the current face + * index (starting with value~1; value~0 indicates font access without + * a named instance). For non-variation fonts, bits 16-30 are ignored. + * If we have the third named instance of face~4, say, `face_index` is + * set to 0x00030004. + * + * Bit 31 is always zero (this is, `face_index` is always a positive + * value). + * + * [Since 2.9] Changing the design coordinates with + * @FT_Set_Var_Design_Coordinates or @FT_Set_Var_Blend_Coordinates does + * not influence the named instance index value (only + * @FT_Set_Named_Instance does that). + * + * face_flags :: + * A set of bit flags that give important information about the face; + * see @FT_FACE_FLAG_XXX for the details. + * + * style_flags :: + * The lower 16~bits contain a set of bit flags indicating the style of + * the face; see @FT_STYLE_FLAG_XXX for the details. + * + * [Since 2.6.1] Bits 16-30 hold the number of named instances + * available for the current face if we have a GX or OpenType variation + * (sub)font. Bit 31 is always zero (this is, `style_flags` is always + * a positive value). Note that a variation font has always at least + * one named instance, namely the default instance. + * + * num_glyphs :: + * The number of glyphs in the face. If the face is scalable and has + * sbits (see `num_fixed_sizes`), it is set to the number of outline + * glyphs. + * + * For CID-keyed fonts (not in an SFNT wrapper) this value gives the + * highest CID used in the font. + * + * family_name :: + * The face's family name. This is an ASCII string, usually in + * English, that describes the typeface's family (like 'Times New + * Roman', 'Bodoni', 'Garamond', etc). This is a least common + * denominator used to list fonts. Some formats (TrueType & OpenType) + * provide localized and Unicode versions of this string. Applications + * should use the format-specific interface to access them. Can be + * `NULL` (e.g., in fonts embedded in a PDF file). + * + * In case the font doesn't provide a specific family name entry, + * FreeType tries to synthesize one, deriving it from other name + * entries. + * + * style_name :: + * The face's style name. This is an ASCII string, usually in English, + * that describes the typeface's style (like 'Italic', 'Bold', + * 'Condensed', etc). Not all font formats provide a style name, so + * this field is optional, and can be set to `NULL`. As for + * `family_name`, some formats provide localized and Unicode versions + * of this string. Applications should use the format-specific + * interface to access them. + * + * num_fixed_sizes :: + * The number of bitmap strikes in the face. Even if the face is + * scalable, there might still be bitmap strikes, which are called + * 'sbits' in that case. + * + * available_sizes :: + * An array of @FT_Bitmap_Size for all bitmap strikes in the face. It + * is set to `NULL` if there is no bitmap strike. + * + * Note that FreeType tries to sanitize the strike data since they are + * sometimes sloppy or incorrect, but this can easily fail. + * + * num_charmaps :: + * The number of charmaps in the face. + * + * charmaps :: + * An array of the charmaps of the face. + * + * generic :: + * A field reserved for client uses. See the @FT_Generic type + * description. + * + * bbox :: + * The font bounding box. Coordinates are expressed in font units (see + * `units_per_EM`). The box is large enough to contain any glyph from + * the font. Thus, `bbox.yMax` can be seen as the 'maximum ascender', + * and `bbox.yMin` as the 'minimum descender'. Only relevant for + * scalable formats. + * + * Note that the bounding box might be off by (at least) one pixel for + * hinted fonts. See @FT_Size_Metrics for further discussion. + * + * units_per_EM :: + * The number of font units per EM square for this face. This is + * typically 2048 for TrueType fonts, and 1000 for Type~1 fonts. Only + * relevant for scalable formats. + * + * ascender :: + * The typographic ascender of the face, expressed in font units. For + * font formats not having this information, it is set to `bbox.yMax`. + * Only relevant for scalable formats. + * + * descender :: + * The typographic descender of the face, expressed in font units. For + * font formats not having this information, it is set to `bbox.yMin`. + * Note that this field is negative for values below the baseline. + * Only relevant for scalable formats. + * + * height :: + * This value is the vertical distance between two consecutive + * baselines, expressed in font units. It is always positive. Only + * relevant for scalable formats. + * + * If you want the global glyph height, use `ascender - descender`. + * + * max_advance_width :: + * The maximum advance width, in font units, for all glyphs in this + * face. This can be used to make word wrapping computations faster. + * Only relevant for scalable formats. + * + * max_advance_height :: + * The maximum advance height, in font units, for all glyphs in this + * face. This is only relevant for vertical layouts, and is set to + * `height` for fonts that do not provide vertical metrics. Only + * relevant for scalable formats. + * + * underline_position :: + * The position, in font units, of the underline line for this face. + * It is the center of the underlining stem. Only relevant for + * scalable formats. + * + * underline_thickness :: + * The thickness, in font units, of the underline for this face. Only + * relevant for scalable formats. + * + * glyph :: + * The face's associated glyph slot(s). + * + * size :: + * The current active size for this face. + * + * charmap :: + * The current active charmap for this face. + * + * @note: + * Fields may be changed after a call to @FT_Attach_File or + * @FT_Attach_Stream. + * + * For an OpenType variation font, the values of the following fields can + * change after a call to @FT_Set_Var_Design_Coordinates (and friends) if + * the font contains an 'MVAR' table: `ascender`, `descender`, `height`, + * `underline_position`, and `underline_thickness`. + * + * Especially for TrueType fonts see also the documentation for + * @FT_Size_Metrics. + */ typedef struct FT_FaceRec_ { FT_Long num_faces; @@ -1087,7 +1059,7 @@ FT_BEGIN_HEADER FT_Generic generic; - /*# The following member variables (down to `underline_thickness') */ + /*# The following member variables (down to `underline_thickness`) */ /*# are only relevant to scalable outlines; cf. @FT_Bitmap_Size */ /*# for bitmap fonts. */ FT_BBox bbox; @@ -1125,117 +1097,116 @@ FT_BEGIN_HEADER } FT_FaceRec; - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_FACE_FLAG_XXX */ - /* */ - /* <Description> */ - /* A list of bit flags used in the `face_flags' field of the */ - /* @FT_FaceRec structure. They inform client applications of */ - /* properties of the corresponding face. */ - /* */ - /* <Values> */ - /* FT_FACE_FLAG_SCALABLE :: */ - /* The face contains outline glyphs. Note that a face can contain */ - /* bitmap strikes also, i.e., a face can have both this flag and */ - /* @FT_FACE_FLAG_FIXED_SIZES set. */ - /* */ - /* FT_FACE_FLAG_FIXED_SIZES :: */ - /* The face contains bitmap strikes. See also the */ - /* `num_fixed_sizes' and `available_sizes' fields of @FT_FaceRec. */ - /* */ - /* FT_FACE_FLAG_FIXED_WIDTH :: */ - /* The face contains fixed-width characters (like Courier, Lucida, */ - /* MonoType, etc.). */ - /* */ - /* FT_FACE_FLAG_SFNT :: */ - /* The face uses the SFNT storage scheme. For now, this means */ - /* TrueType and OpenType. */ - /* */ - /* FT_FACE_FLAG_HORIZONTAL :: */ - /* The face contains horizontal glyph metrics. This should be set */ - /* for all common formats. */ - /* */ - /* FT_FACE_FLAG_VERTICAL :: */ - /* The face contains vertical glyph metrics. This is only */ - /* available in some formats, not all of them. */ - /* */ - /* FT_FACE_FLAG_KERNING :: */ - /* The face contains kerning information. If set, the kerning */ - /* distance can be retrieved using the function @FT_Get_Kerning. */ - /* Otherwise the function always return the vector (0,0). Note */ - /* that FreeType doesn't handle kerning data from the SFNT `GPOS' */ - /* table (as present in many OpenType fonts). */ - /* */ - /* FT_FACE_FLAG_FAST_GLYPHS :: */ - /* THIS FLAG IS DEPRECATED. DO NOT USE OR TEST IT. */ - /* */ - /* FT_FACE_FLAG_MULTIPLE_MASTERS :: */ - /* The face contains multiple masters and is capable of */ - /* interpolating between them. Supported formats are Adobe MM, */ - /* TrueType GX, and OpenType variation fonts. */ - /* */ - /* See section @multiple_masters for API details. */ - /* */ - /* FT_FACE_FLAG_GLYPH_NAMES :: */ - /* The face contains glyph names, which can be retrieved using */ - /* @FT_Get_Glyph_Name. Note that some TrueType fonts contain */ - /* broken glyph name tables. Use the function */ - /* @FT_Has_PS_Glyph_Names when needed. */ - /* */ - /* FT_FACE_FLAG_EXTERNAL_STREAM :: */ - /* Used internally by FreeType to indicate that a face's stream was */ - /* provided by the client application and should not be destroyed */ - /* when @FT_Done_Face is called. Don't read or test this flag. */ - /* */ - /* FT_FACE_FLAG_HINTER :: */ - /* The font driver has a hinting machine of its own. For example, */ - /* with TrueType fonts, it makes sense to use data from the SFNT */ - /* `gasp' table only if the native TrueType hinting engine (with */ - /* the bytecode interpreter) is available and active. */ - /* */ - /* FT_FACE_FLAG_CID_KEYED :: */ - /* The face is CID-keyed. In that case, the face is not accessed */ - /* by glyph indices but by CID values. For subsetted CID-keyed */ - /* fonts this has the consequence that not all index values are a */ - /* valid argument to @FT_Load_Glyph. Only the CID values for which */ - /* corresponding glyphs in the subsetted font exist make */ - /* `FT_Load_Glyph' return successfully; in all other cases you get */ - /* an `FT_Err_Invalid_Argument' error. */ - /* */ - /* Note that CID-keyed fonts that are in an SFNT wrapper (this is, */ - /* all OpenType/CFF fonts) don't have this flag set since the */ - /* glyphs are accessed in the normal way (using contiguous */ - /* indices); the `CID-ness' isn't visible to the application. */ - /* */ - /* FT_FACE_FLAG_TRICKY :: */ - /* The face is `tricky', this is, it always needs the font format's */ - /* native hinting engine to get a reasonable result. A typical */ - /* example is the old Chinese font `mingli.ttf' (but not */ - /* `mingliu.ttc') that uses TrueType bytecode instructions to move */ - /* and scale all of its subglyphs. */ - /* */ - /* It is not possible to auto-hint such fonts using */ - /* @FT_LOAD_FORCE_AUTOHINT; it will also ignore */ - /* @FT_LOAD_NO_HINTING. You have to set both @FT_LOAD_NO_HINTING */ - /* and @FT_LOAD_NO_AUTOHINT to really disable hinting; however, you */ - /* probably never want this except for demonstration purposes. */ - /* */ - /* Currently, there are about a dozen TrueType fonts in the list of */ - /* tricky fonts; they are hard-coded in file `ttobjs.c'. */ - /* */ - /* FT_FACE_FLAG_COLOR :: */ - /* [Since 2.5.1] The face has color glyph tables. To access color */ - /* glyphs use @FT_LOAD_COLOR. */ - /* */ - /* FT_FACE_FLAG_VARIATION :: */ - /* [Since 2.9] Set if the current face (or named instance) has been */ - /* altered with @FT_Set_MM_Design_Coordinates, */ - /* @FT_Set_Var_Design_Coordinates, or */ - /* @FT_Set_Var_Blend_Coordinates. This flag is unset by a call to */ - /* @FT_Set_Named_Instance. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_FACE_FLAG_XXX + * + * @description: + * A list of bit flags used in the `face_flags` field of the @FT_FaceRec + * structure. They inform client applications of properties of the + * corresponding face. + * + * @values: + * FT_FACE_FLAG_SCALABLE :: + * The face contains outline glyphs. Note that a face can contain + * bitmap strikes also, i.e., a face can have both this flag and + * @FT_FACE_FLAG_FIXED_SIZES set. + * + * FT_FACE_FLAG_FIXED_SIZES :: + * The face contains bitmap strikes. See also the `num_fixed_sizes` + * and `available_sizes` fields of @FT_FaceRec. + * + * FT_FACE_FLAG_FIXED_WIDTH :: + * The face contains fixed-width characters (like Courier, Lucida, + * MonoType, etc.). + * + * FT_FACE_FLAG_SFNT :: + * The face uses the SFNT storage scheme. For now, this means TrueType + * and OpenType. + * + * FT_FACE_FLAG_HORIZONTAL :: + * The face contains horizontal glyph metrics. This should be set for + * all common formats. + * + * FT_FACE_FLAG_VERTICAL :: + * The face contains vertical glyph metrics. This is only available in + * some formats, not all of them. + * + * FT_FACE_FLAG_KERNING :: + * The face contains kerning information. If set, the kerning distance + * can be retrieved using the function @FT_Get_Kerning. Otherwise the + * function always return the vector (0,0). Note that FreeType doesn't + * handle kerning data from the SFNT 'GPOS' table (as present in many + * OpenType fonts). + * + * FT_FACE_FLAG_FAST_GLYPHS :: + * THIS FLAG IS DEPRECATED. DO NOT USE OR TEST IT. + * + * FT_FACE_FLAG_MULTIPLE_MASTERS :: + * The face contains multiple masters and is capable of interpolating + * between them. Supported formats are Adobe MM, TrueType GX, and + * OpenType variation fonts. + * + * See section @multiple_masters for API details. + * + * FT_FACE_FLAG_GLYPH_NAMES :: + * The face contains glyph names, which can be retrieved using + * @FT_Get_Glyph_Name. Note that some TrueType fonts contain broken + * glyph name tables. Use the function @FT_Has_PS_Glyph_Names when + * needed. + * + * FT_FACE_FLAG_EXTERNAL_STREAM :: + * Used internally by FreeType to indicate that a face's stream was + * provided by the client application and should not be destroyed when + * @FT_Done_Face is called. Don't read or test this flag. + * + * FT_FACE_FLAG_HINTER :: + * The font driver has a hinting machine of its own. For example, with + * TrueType fonts, it makes sense to use data from the SFNT 'gasp' + * table only if the native TrueType hinting engine (with the bytecode + * interpreter) is available and active. + * + * FT_FACE_FLAG_CID_KEYED :: + * The face is CID-keyed. In that case, the face is not accessed by + * glyph indices but by CID values. For subsetted CID-keyed fonts this + * has the consequence that not all index values are a valid argument + * to @FT_Load_Glyph. Only the CID values for which corresponding + * glyphs in the subsetted font exist make `FT_Load_Glyph` return + * successfully; in all other cases you get an + * `FT_Err_Invalid_Argument` error. + * + * Note that CID-keyed fonts that are in an SFNT wrapper (this is, all + * OpenType/CFF fonts) don't have this flag set since the glyphs are + * accessed in the normal way (using contiguous indices); the + * 'CID-ness' isn't visible to the application. + * + * FT_FACE_FLAG_TRICKY :: + * The face is 'tricky', this is, it always needs the font format's + * native hinting engine to get a reasonable result. A typical example + * is the old Chinese font `mingli.ttf` (but not `mingliu.ttc`) that + * uses TrueType bytecode instructions to move and scale all of its + * subglyphs. + * + * It is not possible to auto-hint such fonts using + * @FT_LOAD_FORCE_AUTOHINT; it will also ignore @FT_LOAD_NO_HINTING. + * You have to set both @FT_LOAD_NO_HINTING and @FT_LOAD_NO_AUTOHINT to + * really disable hinting; however, you probably never want this except + * for demonstration purposes. + * + * Currently, there are about a dozen TrueType fonts in the list of + * tricky fonts; they are hard-coded in file `ttobjs.c`. + * + * FT_FACE_FLAG_COLOR :: + * [Since 2.5.1] The face has color glyph tables. See @FT_LOAD_COLOR + * for more information. + * + * FT_FACE_FLAG_VARIATION :: + * [Since 2.9] Set if the current face (or named instance) has been + * altered with @FT_Set_MM_Design_Coordinates, + * @FT_Set_Var_Design_Coordinates, or @FT_Set_Var_Blend_Coordinates. + * This flag is unset by a call to @FT_Set_Named_Instance. + */ #define FT_FACE_FLAG_SCALABLE ( 1L << 0 ) #define FT_FACE_FLAG_FIXED_SIZES ( 1L << 1 ) #define FT_FACE_FLAG_FIXED_WIDTH ( 1L << 2 ) @@ -1254,14 +1225,14 @@ FT_BEGIN_HEADER #define FT_FACE_FLAG_VARIATION ( 1L << 15 ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_HORIZONTAL( face ) + * FT_HAS_HORIZONTAL * * @description: - * A macro that returns true whenever a face object contains - * horizontal metrics (this is true for all font formats though). + * A macro that returns true whenever a face object contains horizontal + * metrics (this is true for all font formats though). * * @also: * @FT_HAS_VERTICAL can be used to check for vertical metrics. @@ -1271,10 +1242,10 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_HORIZONTAL ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_VERTICAL( face ) + * FT_HAS_VERTICAL * * @description: * A macro that returns true whenever a face object contains real @@ -1285,45 +1256,45 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_VERTICAL ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_KERNING( face ) + * FT_HAS_KERNING * * @description: - * A macro that returns true whenever a face object contains kerning - * data that can be accessed with @FT_Get_Kerning. + * A macro that returns true whenever a face object contains kerning data + * that can be accessed with @FT_Get_Kerning. * */ #define FT_HAS_KERNING( face ) \ ( (face)->face_flags & FT_FACE_FLAG_KERNING ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_SCALABLE( face ) + * FT_IS_SCALABLE * * @description: * A macro that returns true whenever a face object contains a scalable - * font face (true for TrueType, Type~1, Type~42, CID, OpenType/CFF, - * and PFR font formats). + * font face (true for TrueType, Type~1, Type~42, CID, OpenType/CFF, and + * PFR font formats). * */ #define FT_IS_SCALABLE( face ) \ ( (face)->face_flags & FT_FACE_FLAG_SCALABLE ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_SFNT( face ) + * FT_IS_SFNT * * @description: - * A macro that returns true whenever a face object contains a font - * whose format is based on the SFNT storage scheme. This usually - * means: TrueType fonts, OpenType fonts, as well as SFNT-based embedded - * bitmap fonts. + * A macro that returns true whenever a face object contains a font whose + * format is based on the SFNT storage scheme. This usually means: + * TrueType fonts, OpenType fonts, as well as SFNT-based embedded bitmap + * fonts. * * If this macro is true, all functions defined in @FT_SFNT_NAMES_H and * @FT_TRUETYPE_TABLES_H are available. @@ -1333,14 +1304,14 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_SFNT ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_FIXED_WIDTH( face ) + * FT_IS_FIXED_WIDTH * * @description: * A macro that returns true whenever a face object contains a font face - * that contains fixed-width (or `monospace', `fixed-pitch', etc.) + * that contains fixed-width (or 'monospace', 'fixed-pitch', etc.) * glyphs. * */ @@ -1348,25 +1319,25 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_FIXED_WIDTH ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_FIXED_SIZES( face ) + * FT_HAS_FIXED_SIZES * * @description: * A macro that returns true whenever a face object contains some - * embedded bitmaps. See the `available_sizes' field of the - * @FT_FaceRec structure. + * embedded bitmaps. See the `available_sizes` field of the @FT_FaceRec + * structure. * */ #define FT_HAS_FIXED_SIZES( face ) \ ( (face)->face_flags & FT_FACE_FLAG_FIXED_SIZES ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_FAST_GLYPHS( face ) + * FT_HAS_FAST_GLYPHS * * @description: * Deprecated. @@ -1375,10 +1346,10 @@ FT_BEGIN_HEADER #define FT_HAS_FAST_GLYPHS( face ) 0 - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_GLYPH_NAMES( face ) + * FT_HAS_GLYPH_NAMES * * @description: * A macro that returns true whenever a face object contains some glyph @@ -1389,10 +1360,10 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_GLYPH_NAMES ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_MULTIPLE_MASTERS( face ) + * FT_HAS_MULTIPLE_MASTERS * * @description: * A macro that returns true whenever a face object contains some @@ -1404,10 +1375,10 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_MULTIPLE_MASTERS ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_NAMED_INSTANCE( face ) + * FT_IS_NAMED_INSTANCE * * @description: * A macro that returns true whenever a face object is a named instance @@ -1426,14 +1397,14 @@ FT_BEGIN_HEADER ( (face)->face_index & 0x7FFF0000L ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_VARIATION( face ) + * FT_IS_VARIATION * * @description: - * A macro that returns true whenever a face object has been altered - * by @FT_Set_MM_Design_Coordinates, @FT_Set_Var_Design_Coordinates, or + * A macro that returns true whenever a face object has been altered by + * @FT_Set_MM_Design_Coordinates, @FT_Set_Var_Design_Coordinates, or * @FT_Set_Var_Blend_Coordinates. * * @since: @@ -1444,15 +1415,14 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_VARIATION ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_CID_KEYED( face ) + * FT_IS_CID_KEYED * * @description: * A macro that returns true whenever a face object contains a CID-keyed - * font. See the discussion of @FT_FACE_FLAG_CID_KEYED for more - * details. + * font. See the discussion of @FT_FACE_FLAG_CID_KEYED for more details. * * If this macro is true, all functions defined in @FT_CID_H are * available. @@ -1462,13 +1432,13 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_CID_KEYED ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_IS_TRICKY( face ) + * FT_IS_TRICKY * * @description: - * A macro that returns true whenever a face represents a `tricky' font. + * A macro that returns true whenever a face represents a 'tricky' font. * See the discussion of @FT_FACE_FLAG_TRICKY for more details. * */ @@ -1476,14 +1446,14 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_TRICKY ) - /************************************************************************* + /************************************************************************** * * @macro: - * FT_HAS_COLOR( face ) + * FT_HAS_COLOR * * @description: - * A macro that returns true whenever a face object contains - * tables for color glyphs. + * A macro that returns true whenever a face object contains tables for + * color glyphs. * * @since: * 2.5.1 @@ -1493,149 +1463,148 @@ FT_BEGIN_HEADER ( (face)->face_flags & FT_FACE_FLAG_COLOR ) - /*************************************************************************/ - /* */ - /* <Const> */ - /* FT_STYLE_FLAG_XXX */ - /* */ - /* <Description> */ - /* A list of bit flags to indicate the style of a given face. These */ - /* are used in the `style_flags' field of @FT_FaceRec. */ - /* */ - /* <Values> */ - /* FT_STYLE_FLAG_ITALIC :: */ - /* The face style is italic or oblique. */ - /* */ - /* FT_STYLE_FLAG_BOLD :: */ - /* The face is bold. */ - /* */ - /* <Note> */ - /* The style information as provided by FreeType is very basic. More */ - /* details are beyond the scope and should be done on a higher level */ - /* (for example, by analyzing various fields of the `OS/2' table in */ - /* SFNT based fonts). */ - /* */ + /************************************************************************** + * + * @enum: + * FT_STYLE_FLAG_XXX + * + * @description: + * A list of bit flags to indicate the style of a given face. These are + * used in the `style_flags` field of @FT_FaceRec. + * + * @values: + * FT_STYLE_FLAG_ITALIC :: + * The face style is italic or oblique. + * + * FT_STYLE_FLAG_BOLD :: + * The face is bold. + * + * @note: + * The style information as provided by FreeType is very basic. More + * details are beyond the scope and should be done on a higher level (for + * example, by analyzing various fields of the 'OS/2' table in SFNT based + * fonts). + */ #define FT_STYLE_FLAG_ITALIC ( 1 << 0 ) #define FT_STYLE_FLAG_BOLD ( 1 << 1 ) - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Size_Internal */ - /* */ - /* <Description> */ - /* An opaque handle to an `FT_Size_InternalRec' structure, used to */ - /* model private data of a given @FT_Size object. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Size_Internal + * + * @description: + * An opaque handle to an `FT_Size_InternalRec` structure, used to model + * private data of a given @FT_Size object. + */ typedef struct FT_Size_InternalRec_* FT_Size_Internal; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Size_Metrics */ - /* */ - /* <Description> */ - /* The size metrics structure gives the metrics of a size object. */ - /* */ - /* <Fields> */ - /* x_ppem :: The width of the scaled EM square in pixels, hence */ - /* the term `ppem' (pixels per EM). It is also */ - /* referred to as `nominal width'. */ - /* */ - /* y_ppem :: The height of the scaled EM square in pixels, */ - /* hence the term `ppem' (pixels per EM). It is also */ - /* referred to as `nominal height'. */ - /* */ - /* x_scale :: A 16.16 fractional scaling value to convert */ - /* horizontal metrics from font units to 26.6 */ - /* fractional pixels. Only relevant for scalable */ - /* font formats. */ - /* */ - /* y_scale :: A 16.16 fractional scaling value to convert */ - /* vertical metrics from font units to 26.6 */ - /* fractional pixels. Only relevant for scalable */ - /* font formats. */ - /* */ - /* ascender :: The ascender in 26.6 fractional pixels, rounded up */ - /* to an integer value. See @FT_FaceRec for the */ - /* details. */ - /* */ - /* descender :: The descender in 26.6 fractional pixels, rounded */ - /* down to an integer value. See @FT_FaceRec for the */ - /* details. */ - /* */ - /* height :: The height in 26.6 fractional pixels, rounded to */ - /* an integer value. See @FT_FaceRec for the */ - /* details. */ - /* */ - /* max_advance :: The maximum advance width in 26.6 fractional */ - /* pixels, rounded to an integer value. See */ - /* @FT_FaceRec for the details. */ - /* */ - /* <Note> */ - /* The scaling values, if relevant, are determined first during a */ - /* size changing operation. The remaining fields are then set by the */ - /* driver. For scalable formats, they are usually set to scaled */ - /* values of the corresponding fields in @FT_FaceRec. Some values */ - /* like ascender or descender are rounded for historical reasons; */ - /* more precise values (for outline fonts) can be derived by scaling */ - /* the corresponding @FT_FaceRec values manually, with code similar */ - /* to the following. */ - /* */ - /* { */ - /* scaled_ascender = FT_MulFix( face->ascender, */ - /* size_metrics->y_scale ); */ - /* } */ - /* */ - /* Note that due to glyph hinting and the selected rendering mode */ - /* these values are usually not exact; consequently, they must be */ - /* treated as unreliable with an error margin of at least one pixel! */ - /* */ - /* Indeed, the only way to get the exact metrics is to render _all_ */ - /* glyphs. As this would be a definite performance hit, it is up to */ - /* client applications to perform such computations. */ - /* */ - /* The `FT_Size_Metrics' structure is valid for bitmap fonts also. */ - /* */ - /* */ - /* *TrueType* *fonts* *with* *native* *bytecode* *hinting* */ - /* */ - /* All applications that handle TrueType fonts with native hinting */ - /* must be aware that TTFs expect different rounding of vertical font */ - /* dimensions. The application has to cater for this, especially if */ - /* it wants to rely on a TTF's vertical data (for example, to */ - /* properly align box characters vertically). */ - /* */ - /* Only the application knows _in_ _advance_ that it is going to use */ - /* native hinting for TTFs! FreeType, on the other hand, selects the */ - /* hinting mode not at the time of creating an @FT_Size object but */ - /* much later, namely while calling @FT_Load_Glyph. */ - /* */ - /* Here is some pseudo code that illustrates a possible solution. */ - /* */ - /* { */ - /* font_format = FT_Get_Font_Format( face ); */ - /* */ - /* if ( !strcmp( font_format, "TrueType" ) && */ - /* do_native_bytecode_hinting ) */ - /* { */ - /* ascender = ROUND( FT_MulFix( face->ascender, */ - /* size_metrics->y_scale ) ); */ - /* descender = ROUND( FT_MulFix( face->descender, */ - /* size_metrics->y_scale ) ); */ - /* } */ - /* else */ - /* { */ - /* ascender = size_metrics->ascender; */ - /* descender = size_metrics->descender; */ - /* } */ - /* */ - /* height = size_metrics->height; */ - /* max_advance = size_metrics->max_advance; */ - /* } */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Size_Metrics + * + * @description: + * The size metrics structure gives the metrics of a size object. + * + * @fields: + * x_ppem :: + * The width of the scaled EM square in pixels, hence the term 'ppem' + * (pixels per EM). It is also referred to as 'nominal width'. + * + * y_ppem :: + * The height of the scaled EM square in pixels, hence the term 'ppem' + * (pixels per EM). It is also referred to as 'nominal height'. + * + * x_scale :: + * A 16.16 fractional scaling value to convert horizontal metrics from + * font units to 26.6 fractional pixels. Only relevant for scalable + * font formats. + * + * y_scale :: + * A 16.16 fractional scaling value to convert vertical metrics from + * font units to 26.6 fractional pixels. Only relevant for scalable + * font formats. + * + * ascender :: + * The ascender in 26.6 fractional pixels, rounded up to an integer + * value. See @FT_FaceRec for the details. + * + * descender :: + * The descender in 26.6 fractional pixels, rounded down to an integer + * value. See @FT_FaceRec for the details. + * + * height :: + * The height in 26.6 fractional pixels, rounded to an integer value. + * See @FT_FaceRec for the details. + * + * max_advance :: + * The maximum advance width in 26.6 fractional pixels, rounded to an + * integer value. See @FT_FaceRec for the details. + * + * @note: + * The scaling values, if relevant, are determined first during a size + * changing operation. The remaining fields are then set by the driver. + * For scalable formats, they are usually set to scaled values of the + * corresponding fields in @FT_FaceRec. Some values like ascender or + * descender are rounded for historical reasons; more precise values (for + * outline fonts) can be derived by scaling the corresponding @FT_FaceRec + * values manually, with code similar to the following. + * + * ``` + * scaled_ascender = FT_MulFix( face->ascender, + * size_metrics->y_scale ); + * ``` + * + * Note that due to glyph hinting and the selected rendering mode these + * values are usually not exact; consequently, they must be treated as + * unreliable with an error margin of at least one pixel! + * + * Indeed, the only way to get the exact metrics is to render _all_ + * glyphs. As this would be a definite performance hit, it is up to + * client applications to perform such computations. + * + * The `FT_Size_Metrics` structure is valid for bitmap fonts also. + * + * + * **TrueType fonts with native bytecode hinting** + * + * All applications that handle TrueType fonts with native hinting must + * be aware that TTFs expect different rounding of vertical font + * dimensions. The application has to cater for this, especially if it + * wants to rely on a TTF's vertical data (for example, to properly align + * box characters vertically). + * + * Only the application knows _in advance_ that it is going to use native + * hinting for TTFs! FreeType, on the other hand, selects the hinting + * mode not at the time of creating an @FT_Size object but much later, + * namely while calling @FT_Load_Glyph. + * + * Here is some pseudo code that illustrates a possible solution. + * + * ``` + * font_format = FT_Get_Font_Format( face ); + * + * if ( !strcmp( font_format, "TrueType" ) && + * do_native_bytecode_hinting ) + * { + * ascender = ROUND( FT_MulFix( face->ascender, + * size_metrics->y_scale ) ); + * descender = ROUND( FT_MulFix( face->descender, + * size_metrics->y_scale ) ); + * } + * else + * { + * ascender = size_metrics->ascender; + * descender = size_metrics->descender; + * } + * + * height = size_metrics->height; + * max_advance = size_metrics->max_advance; + * ``` + */ typedef struct FT_Size_Metrics_ { FT_UShort x_ppem; /* horizontal pixels per EM */ @@ -1652,25 +1621,27 @@ FT_BEGIN_HEADER } FT_Size_Metrics; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_SizeRec */ - /* */ - /* <Description> */ - /* FreeType root size class structure. A size object models a face */ - /* object at a given size. */ - /* */ - /* <Fields> */ - /* face :: Handle to the parent face object. */ - /* */ - /* generic :: A typeless pointer, unused by the FreeType library or */ - /* any of its drivers. It can be used by client */ - /* applications to link their own data to each size */ - /* object. */ - /* */ - /* metrics :: Metrics for this size object. This field is read-only. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_SizeRec + * + * @description: + * FreeType root size class structure. A size object models a face + * object at a given size. + * + * @fields: + * face :: + * Handle to the parent face object. + * + * generic :: + * A typeless pointer, unused by the FreeType library or any of its + * drivers. It can be used by client applications to link their own + * data to each size object. + * + * metrics :: + * Metrics for this size object. This field is read-only. + */ typedef struct FT_SizeRec_ { FT_Face face; /* parent face object */ @@ -1681,237 +1652,234 @@ FT_BEGIN_HEADER } FT_SizeRec; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_SubGlyph */ - /* */ - /* <Description> */ - /* The subglyph structure is an internal object used to describe */ - /* subglyphs (for example, in the case of composites). */ - /* */ - /* <Note> */ - /* The subglyph implementation is not part of the high-level API, */ - /* hence the forward structure declaration. */ - /* */ - /* You can however retrieve subglyph information with */ - /* @FT_Get_SubGlyph_Info. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_SubGlyph + * + * @description: + * The subglyph structure is an internal object used to describe + * subglyphs (for example, in the case of composites). + * + * @note: + * The subglyph implementation is not part of the high-level API, hence + * the forward structure declaration. + * + * You can however retrieve subglyph information with + * @FT_Get_SubGlyph_Info. + */ typedef struct FT_SubGlyphRec_* FT_SubGlyph; - /*************************************************************************/ - /* */ - /* <Type> */ - /* FT_Slot_Internal */ - /* */ - /* <Description> */ - /* An opaque handle to an `FT_Slot_InternalRec' structure, used to */ - /* model private data of a given @FT_GlyphSlot object. */ - /* */ + /************************************************************************** + * + * @type: + * FT_Slot_Internal + * + * @description: + * An opaque handle to an `FT_Slot_InternalRec` structure, used to model + * private data of a given @FT_GlyphSlot object. + */ typedef struct FT_Slot_InternalRec_* FT_Slot_Internal; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_GlyphSlotRec */ - /* */ - /* <Description> */ - /* FreeType root glyph slot class structure. A glyph slot is a */ - /* container where individual glyphs can be loaded, be they in */ - /* outline or bitmap format. */ - /* */ - /* <Fields> */ - /* library :: A handle to the FreeType library instance */ - /* this slot belongs to. */ - /* */ - /* face :: A handle to the parent face object. */ - /* */ - /* next :: In some cases (like some font tools), several */ - /* glyph slots per face object can be a good */ - /* thing. As this is rare, the glyph slots are */ - /* listed through a direct, single-linked list */ - /* using its `next' field. */ - /* */ - /* generic :: A typeless pointer unused by the FreeType */ - /* library or any of its drivers. It can be */ - /* used by client applications to link their own */ - /* data to each glyph slot object. */ - /* */ - /* metrics :: The metrics of the last loaded glyph in the */ - /* slot. The returned values depend on the last */ - /* load flags (see the @FT_Load_Glyph API */ - /* function) and can be expressed either in 26.6 */ - /* fractional pixels or font units. */ - /* */ - /* Note that even when the glyph image is */ - /* transformed, the metrics are not. */ - /* */ - /* linearHoriAdvance :: The advance width of the unhinted glyph. */ - /* Its value is expressed in 16.16 fractional */ - /* pixels, unless @FT_LOAD_LINEAR_DESIGN is set */ - /* when loading the glyph. This field can be */ - /* important to perform correct WYSIWYG layout. */ - /* Only relevant for outline glyphs. */ - /* */ - /* linearVertAdvance :: The advance height of the unhinted glyph. */ - /* Its value is expressed in 16.16 fractional */ - /* pixels, unless @FT_LOAD_LINEAR_DESIGN is set */ - /* when loading the glyph. This field can be */ - /* important to perform correct WYSIWYG layout. */ - /* Only relevant for outline glyphs. */ - /* */ - /* advance :: This shorthand is, depending on */ - /* @FT_LOAD_IGNORE_TRANSFORM, the transformed */ - /* (hinted) advance width for the glyph, in 26.6 */ - /* fractional pixel format. As specified with */ - /* @FT_LOAD_VERTICAL_LAYOUT, it uses either the */ - /* `horiAdvance' or the `vertAdvance' value of */ - /* `metrics' field. */ - /* */ - /* format :: This field indicates the format of the image */ - /* contained in the glyph slot. Typically */ - /* @FT_GLYPH_FORMAT_BITMAP, */ - /* @FT_GLYPH_FORMAT_OUTLINE, or */ - /* @FT_GLYPH_FORMAT_COMPOSITE, but other values */ - /* are possible. */ - /* */ - /* bitmap :: This field is used as a bitmap descriptor. */ - /* Note that the address and content of the */ - /* bitmap buffer can change between calls of */ - /* @FT_Load_Glyph and a few other functions. */ - /* */ - /* bitmap_left :: The bitmap's left bearing expressed in */ - /* integer pixels. */ - /* */ - /* bitmap_top :: The bitmap's top bearing expressed in integer */ - /* pixels. This is the distance from the */ - /* baseline to the top-most glyph scanline, */ - /* upwards y~coordinates being *positive*. */ - /* */ - /* outline :: The outline descriptor for the current glyph */ - /* image if its format is */ - /* @FT_GLYPH_FORMAT_OUTLINE. Once a glyph is */ - /* loaded, `outline' can be transformed, */ - /* distorted, emboldened, etc. However, it must */ - /* not be freed. */ - /* */ - /* num_subglyphs :: The number of subglyphs in a composite glyph. */ - /* This field is only valid for the composite */ - /* glyph format that should normally only be */ - /* loaded with the @FT_LOAD_NO_RECURSE flag. */ - /* */ - /* subglyphs :: An array of subglyph descriptors for */ - /* composite glyphs. There are `num_subglyphs' */ - /* elements in there. Currently internal to */ - /* FreeType. */ - /* */ - /* control_data :: Certain font drivers can also return the */ - /* control data for a given glyph image (e.g. */ - /* TrueType bytecode, Type~1 charstrings, etc.). */ - /* This field is a pointer to such data; it is */ - /* currently internal to FreeType. */ - /* */ - /* control_len :: This is the length in bytes of the control */ - /* data. Currently internal to FreeType. */ - /* */ - /* other :: Reserved. */ - /* */ - /* lsb_delta :: The difference between hinted and unhinted */ - /* left side bearing while auto-hinting is */ - /* active. Zero otherwise. */ - /* */ - /* rsb_delta :: The difference between hinted and unhinted */ - /* right side bearing while auto-hinting is */ - /* active. Zero otherwise. */ - /* */ - /* <Note> */ - /* If @FT_Load_Glyph is called with default flags (see */ - /* @FT_LOAD_DEFAULT) the glyph image is loaded in the glyph slot in */ - /* its native format (e.g., an outline glyph for TrueType and Type~1 */ - /* formats). [Since 2.9] The prospective bitmap metrics are */ - /* calculated according to @FT_LOAD_TARGET_XXX and other flags even */ - /* for the outline glyph, even if @FT_LOAD_RENDER is not set. */ - /* */ - /* This image can later be converted into a bitmap by calling */ - /* @FT_Render_Glyph. This function searches the current renderer for */ - /* the native image's format, then invokes it. */ - /* */ - /* The renderer is in charge of transforming the native image through */ - /* the slot's face transformation fields, then converting it into a */ - /* bitmap that is returned in `slot->bitmap'. */ - /* */ - /* Note that `slot->bitmap_left' and `slot->bitmap_top' are also used */ - /* to specify the position of the bitmap relative to the current pen */ - /* position (e.g., coordinates (0,0) on the baseline). Of course, */ - /* `slot->format' is also changed to @FT_GLYPH_FORMAT_BITMAP. */ - /* */ - /* Here is a small pseudo code fragment that shows how to use */ - /* `lsb_delta' and `rsb_delta' to do fractional positioning of */ - /* glyphs: */ - /* */ - /* { */ - /* FT_GlyphSlot slot = face->glyph; */ - /* FT_Pos origin_x = 0; */ - /* */ - /* */ - /* for all glyphs do */ - /* <load glyph with `FT_Load_Glyph'> */ - /* */ - /* FT_Outline_Translate( slot->outline, origin_x & 63, 0 ); */ - /* */ - /* <save glyph image, or render glyph, or ...> */ - /* */ - /* <compute kern between current and next glyph */ - /* and add it to `origin_x'> */ - /* */ - /* origin_x += slot->advance.x; */ - /* origin_x += slot->rsb_delta - slot->lsb_delta; */ - /* endfor */ - /* } */ - /* */ - /* Here is another small pseudo code fragment that shows how to use */ - /* `lsb_delta' and `rsb_delta' to improve integer positioning of */ - /* glyphs: */ - /* */ - /* { */ - /* FT_GlyphSlot slot = face->glyph; */ - /* FT_Pos origin_x = 0; */ - /* FT_Pos prev_rsb_delta = 0; */ - /* */ - /* */ - /* for all glyphs do */ - /* <compute kern between current and previous glyph */ - /* and add it to `origin_x'> */ - /* */ - /* <load glyph with `FT_Load_Glyph'> */ - /* */ - /* if ( prev_rsb_delta - slot->lsb_delta > 32 ) */ - /* origin_x -= 64; */ - /* else if ( prev_rsb_delta - slot->lsb_delta < -31 ) */ - /* origin_x += 64; */ - /* */ - /* prev_rsb_delta = slot->rsb_delta; */ - /* */ - /* <save glyph image, or render glyph, or ...> */ - /* */ - /* origin_x += slot->advance.x; */ - /* endfor */ - /* } */ - /* */ - /* If you use strong auto-hinting, you *must* apply these delta */ - /* values! Otherwise you will experience far too large inter-glyph */ - /* spacing at small rendering sizes in most cases. Note that it */ - /* doesn't harm to use the above code for other hinting modes also, */ - /* since the delta values are zero then. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_GlyphSlotRec + * + * @description: + * FreeType root glyph slot class structure. A glyph slot is a container + * where individual glyphs can be loaded, be they in outline or bitmap + * format. + * + * @fields: + * library :: + * A handle to the FreeType library instance this slot belongs to. + * + * face :: + * A handle to the parent face object. + * + * next :: + * In some cases (like some font tools), several glyph slots per face + * object can be a good thing. As this is rare, the glyph slots are + * listed through a direct, single-linked list using its `next` field. + * + * glyph_index :: + * [Since 2.10] The glyph index passed as an argument to @FT_Load_Glyph + * while initializing the glyph slot. + * + * generic :: + * A typeless pointer unused by the FreeType library or any of its + * drivers. It can be used by client applications to link their own + * data to each glyph slot object. + * + * metrics :: + * The metrics of the last loaded glyph in the slot. The returned + * values depend on the last load flags (see the @FT_Load_Glyph API + * function) and can be expressed either in 26.6 fractional pixels or + * font units. + * + * Note that even when the glyph image is transformed, the metrics are + * not. + * + * linearHoriAdvance :: + * The advance width of the unhinted glyph. Its value is expressed in + * 16.16 fractional pixels, unless @FT_LOAD_LINEAR_DESIGN is set when + * loading the glyph. This field can be important to perform correct + * WYSIWYG layout. Only relevant for outline glyphs. + * + * linearVertAdvance :: + * The advance height of the unhinted glyph. Its value is expressed in + * 16.16 fractional pixels, unless @FT_LOAD_LINEAR_DESIGN is set when + * loading the glyph. This field can be important to perform correct + * WYSIWYG layout. Only relevant for outline glyphs. + * + * advance :: + * This shorthand is, depending on @FT_LOAD_IGNORE_TRANSFORM, the + * transformed (hinted) advance width for the glyph, in 26.6 fractional + * pixel format. As specified with @FT_LOAD_VERTICAL_LAYOUT, it uses + * either the `horiAdvance` or the `vertAdvance` value of `metrics` + * field. + * + * format :: + * This field indicates the format of the image contained in the glyph + * slot. Typically @FT_GLYPH_FORMAT_BITMAP, @FT_GLYPH_FORMAT_OUTLINE, + * or @FT_GLYPH_FORMAT_COMPOSITE, but other values are possible. + * + * bitmap :: + * This field is used as a bitmap descriptor. Note that the address + * and content of the bitmap buffer can change between calls of + * @FT_Load_Glyph and a few other functions. + * + * bitmap_left :: + * The bitmap's left bearing expressed in integer pixels. + * + * bitmap_top :: + * The bitmap's top bearing expressed in integer pixels. This is the + * distance from the baseline to the top-most glyph scanline, upwards + * y~coordinates being **positive**. + * + * outline :: + * The outline descriptor for the current glyph image if its format is + * @FT_GLYPH_FORMAT_OUTLINE. Once a glyph is loaded, `outline` can be + * transformed, distorted, emboldened, etc. However, it must not be + * freed. + * + * num_subglyphs :: + * The number of subglyphs in a composite glyph. This field is only + * valid for the composite glyph format that should normally only be + * loaded with the @FT_LOAD_NO_RECURSE flag. + * + * subglyphs :: + * An array of subglyph descriptors for composite glyphs. There are + * `num_subglyphs` elements in there. Currently internal to FreeType. + * + * control_data :: + * Certain font drivers can also return the control data for a given + * glyph image (e.g. TrueType bytecode, Type~1 charstrings, etc.). + * This field is a pointer to such data; it is currently internal to + * FreeType. + * + * control_len :: + * This is the length in bytes of the control data. Currently internal + * to FreeType. + * + * other :: + * Reserved. + * + * lsb_delta :: + * The difference between hinted and unhinted left side bearing while + * auto-hinting is active. Zero otherwise. + * + * rsb_delta :: + * The difference between hinted and unhinted right side bearing while + * auto-hinting is active. Zero otherwise. + * + * @note: + * If @FT_Load_Glyph is called with default flags (see @FT_LOAD_DEFAULT) + * the glyph image is loaded in the glyph slot in its native format + * (e.g., an outline glyph for TrueType and Type~1 formats). [Since 2.9] + * The prospective bitmap metrics are calculated according to + * @FT_LOAD_TARGET_XXX and other flags even for the outline glyph, even + * if @FT_LOAD_RENDER is not set. + * + * This image can later be converted into a bitmap by calling + * @FT_Render_Glyph. This function searches the current renderer for the + * native image's format, then invokes it. + * + * The renderer is in charge of transforming the native image through the + * slot's face transformation fields, then converting it into a bitmap + * that is returned in `slot->bitmap`. + * + * Note that `slot->bitmap_left` and `slot->bitmap_top` are also used to + * specify the position of the bitmap relative to the current pen + * position (e.g., coordinates (0,0) on the baseline). Of course, + * `slot->format` is also changed to @FT_GLYPH_FORMAT_BITMAP. + * + * Here is a small pseudo code fragment that shows how to use `lsb_delta` + * and `rsb_delta` to do fractional positioning of glyphs: + * + * ``` + * FT_GlyphSlot slot = face->glyph; + * FT_Pos origin_x = 0; + * + * + * for all glyphs do + * <load glyph with `FT_Load_Glyph'> + * + * FT_Outline_Translate( slot->outline, origin_x & 63, 0 ); + * + * <save glyph image, or render glyph, or ...> + * + * <compute kern between current and next glyph + * and add it to `origin_x'> + * + * origin_x += slot->advance.x; + * origin_x += slot->lsb_delta - slot->rsb_delta; + * endfor + * ``` + * + * Here is another small pseudo code fragment that shows how to use + * `lsb_delta` and `rsb_delta` to improve integer positioning of glyphs: + * + * ``` + * FT_GlyphSlot slot = face->glyph; + * FT_Pos origin_x = 0; + * FT_Pos prev_rsb_delta = 0; + * + * + * for all glyphs do + * <compute kern between current and previous glyph + * and add it to `origin_x'> + * + * <load glyph with `FT_Load_Glyph'> + * + * if ( prev_rsb_delta - slot->lsb_delta > 32 ) + * origin_x -= 64; + * else if ( prev_rsb_delta - slot->lsb_delta < -31 ) + * origin_x += 64; + * + * prev_rsb_delta = slot->rsb_delta; + * + * <save glyph image, or render glyph, or ...> + * + * origin_x += slot->advance.x; + * endfor + * ``` + * + * If you use strong auto-hinting, you **must** apply these delta values! + * Otherwise you will experience far too large inter-glyph spacing at + * small rendering sizes in most cases. Note that it doesn't harm to use + * the above code for other hinting modes also, since the delta values + * are zero then. + */ typedef struct FT_GlyphSlotRec_ { FT_Library library; FT_Face face; FT_GlyphSlot next; - FT_UInt reserved; /* retained for binary compatibility */ + FT_UInt glyph_index; /* new in 2.10; was reserved previously */ FT_Generic generic; FT_Glyph_Metrics metrics; @@ -1952,86 +1920,92 @@ FT_BEGIN_HEADER /*************************************************************************/ - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Init_FreeType */ - /* */ - /* <Description> */ - /* Initialize a new FreeType library object. The set of modules */ - /* that are registered by this function is determined at build time. */ - /* */ - /* <Output> */ - /* alibrary :: A handle to a new library object. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* In case you want to provide your own memory allocating routines, */ - /* use @FT_New_Library instead, followed by a call to */ - /* @FT_Add_Default_Modules (or a series of calls to @FT_Add_Module) */ - /* and @FT_Set_Default_Properties. */ - /* */ - /* See the documentation of @FT_Library and @FT_Face for */ - /* multi-threading issues. */ - /* */ - /* If you need reference-counting (cf. @FT_Reference_Library), use */ - /* @FT_New_Library and @FT_Done_Library. */ - /* */ - /* If compilation option FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES is */ - /* set, this function reads the `FREETYPE_PROPERTIES' environment */ - /* variable to control driver properties. See section @properties */ - /* for more. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Init_FreeType + * + * @description: + * Initialize a new FreeType library object. The set of modules that are + * registered by this function is determined at build time. + * + * @output: + * alibrary :: + * A handle to a new library object. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * In case you want to provide your own memory allocating routines, use + * @FT_New_Library instead, followed by a call to @FT_Add_Default_Modules + * (or a series of calls to @FT_Add_Module) and + * @FT_Set_Default_Properties. + * + * See the documentation of @FT_Library and @FT_Face for multi-threading + * issues. + * + * If you need reference-counting (cf. @FT_Reference_Library), use + * @FT_New_Library and @FT_Done_Library. + * + * If compilation option `FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES` is + * set, this function reads the `FREETYPE_PROPERTIES` environment + * variable to control driver properties. See section @properties for + * more. + */ FT_EXPORT( FT_Error ) FT_Init_FreeType( FT_Library *alibrary ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Done_FreeType */ - /* */ - /* <Description> */ - /* Destroy a given FreeType library object and all of its children, */ - /* including resources, drivers, faces, sizes, etc. */ - /* */ - /* <Input> */ - /* library :: A handle to the target library object. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Done_FreeType + * + * @description: + * Destroy a given FreeType library object and all of its children, + * including resources, drivers, faces, sizes, etc. + * + * @input: + * library :: + * A handle to the target library object. + * + * @return: + * FreeType error code. 0~means success. + */ FT_EXPORT( FT_Error ) FT_Done_FreeType( FT_Library library ); - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_OPEN_XXX */ - /* */ - /* <Description> */ - /* A list of bit field constants used within the `flags' field of the */ - /* @FT_Open_Args structure. */ - /* */ - /* <Values> */ - /* FT_OPEN_MEMORY :: This is a memory-based stream. */ - /* */ - /* FT_OPEN_STREAM :: Copy the stream from the `stream' field. */ - /* */ - /* FT_OPEN_PATHNAME :: Create a new input stream from a C~path */ - /* name. */ - /* */ - /* FT_OPEN_DRIVER :: Use the `driver' field. */ - /* */ - /* FT_OPEN_PARAMS :: Use the `num_params' and `params' fields. */ - /* */ - /* <Note> */ - /* The `FT_OPEN_MEMORY', `FT_OPEN_STREAM', and `FT_OPEN_PATHNAME' */ - /* flags are mutually exclusive. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_OPEN_XXX + * + * @description: + * A list of bit field constants used within the `flags` field of the + * @FT_Open_Args structure. + * + * @values: + * FT_OPEN_MEMORY :: + * This is a memory-based stream. + * + * FT_OPEN_STREAM :: + * Copy the stream from the `stream` field. + * + * FT_OPEN_PATHNAME :: + * Create a new input stream from a C~path name. + * + * FT_OPEN_DRIVER :: + * Use the `driver` field. + * + * FT_OPEN_PARAMS :: + * Use the `num_params` and `params` fields. + * + * @note: + * The `FT_OPEN_MEMORY`, `FT_OPEN_STREAM`, and `FT_OPEN_PATHNAME` flags + * are mutually exclusive. + */ #define FT_OPEN_MEMORY 0x1 #define FT_OPEN_STREAM 0x2 #define FT_OPEN_PATHNAME 0x4 @@ -2039,7 +2013,7 @@ FT_BEGIN_HEADER #define FT_OPEN_PARAMS 0x10 - /* these constants are deprecated; use the corresponding `FT_OPEN_XXX' */ + /* these constants are deprecated; use the corresponding `FT_OPEN_XXX` */ /* values instead */ #define ft_open_memory FT_OPEN_MEMORY #define ft_open_stream FT_OPEN_STREAM @@ -2048,24 +2022,26 @@ FT_BEGIN_HEADER #define ft_open_params FT_OPEN_PARAMS - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Parameter */ - /* */ - /* <Description> */ - /* A simple structure to pass more or less generic parameters to */ - /* @FT_Open_Face and @FT_Face_Properties. */ - /* */ - /* <Fields> */ - /* tag :: A four-byte identification tag. */ - /* */ - /* data :: A pointer to the parameter data. */ - /* */ - /* <Note> */ - /* The ID and function of parameters are driver-specific. See */ - /* section @parameter_tags for more information. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Parameter + * + * @description: + * A simple structure to pass more or less generic parameters to + * @FT_Open_Face and @FT_Face_Properties. + * + * @fields: + * tag :: + * A four-byte identification tag. + * + * data :: + * A pointer to the parameter data. + * + * @note: + * The ID and function of parameters are driver-specific. See section + * @parameter_tags for more information. + */ typedef struct FT_Parameter_ { FT_ULong tag; @@ -2074,65 +2050,69 @@ FT_BEGIN_HEADER } FT_Parameter; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Open_Args */ - /* */ - /* <Description> */ - /* A structure to indicate how to open a new font file or stream. A */ - /* pointer to such a structure can be used as a parameter for the */ - /* functions @FT_Open_Face and @FT_Attach_Stream. */ - /* */ - /* <Fields> */ - /* flags :: A set of bit flags indicating how to use the */ - /* structure. */ - /* */ - /* memory_base :: The first byte of the file in memory. */ - /* */ - /* memory_size :: The size in bytes of the file in memory. */ - /* */ - /* pathname :: A pointer to an 8-bit file pathname. */ - /* */ - /* stream :: A handle to a source stream object. */ - /* */ - /* driver :: This field is exclusively used by @FT_Open_Face; */ - /* it simply specifies the font driver to use for */ - /* opening the face. If set to NULL, FreeType tries */ - /* to load the face with each one of the drivers in */ - /* its list. */ - /* */ - /* num_params :: The number of extra parameters. */ - /* */ - /* params :: Extra parameters passed to the font driver when */ - /* opening a new face. */ - /* */ - /* <Note> */ - /* The stream type is determined by the contents of `flags' that */ - /* are tested in the following order by @FT_Open_Face: */ - /* */ - /* If the @FT_OPEN_MEMORY bit is set, assume that this is a */ - /* memory file of `memory_size' bytes, located at `memory_address'. */ - /* The data are not copied, and the client is responsible for */ - /* releasing and destroying them _after_ the corresponding call to */ - /* @FT_Done_Face. */ - /* */ - /* Otherwise, if the @FT_OPEN_STREAM bit is set, assume that a */ - /* custom input stream `stream' is used. */ - /* */ - /* Otherwise, if the @FT_OPEN_PATHNAME bit is set, assume that this */ - /* is a normal file and use `pathname' to open it. */ - /* */ - /* If the @FT_OPEN_DRIVER bit is set, @FT_Open_Face only tries to */ - /* open the file with the driver whose handler is in `driver'. */ - /* */ - /* If the @FT_OPEN_PARAMS bit is set, the parameters given by */ - /* `num_params' and `params' is used. They are ignored otherwise. */ - /* */ - /* Ideally, both the `pathname' and `params' fields should be tagged */ - /* as `const'; this is missing for API backward compatibility. In */ - /* other words, applications should treat them as read-only. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Open_Args + * + * @description: + * A structure to indicate how to open a new font file or stream. A + * pointer to such a structure can be used as a parameter for the + * functions @FT_Open_Face and @FT_Attach_Stream. + * + * @fields: + * flags :: + * A set of bit flags indicating how to use the structure. + * + * memory_base :: + * The first byte of the file in memory. + * + * memory_size :: + * The size in bytes of the file in memory. + * + * pathname :: + * A pointer to an 8-bit file pathname. + * + * stream :: + * A handle to a source stream object. + * + * driver :: + * This field is exclusively used by @FT_Open_Face; it simply specifies + * the font driver to use for opening the face. If set to `NULL`, + * FreeType tries to load the face with each one of the drivers in its + * list. + * + * num_params :: + * The number of extra parameters. + * + * params :: + * Extra parameters passed to the font driver when opening a new face. + * + * @note: + * The stream type is determined by the contents of `flags` that are + * tested in the following order by @FT_Open_Face: + * + * If the @FT_OPEN_MEMORY bit is set, assume that this is a memory file + * of `memory_size` bytes, located at `memory_address`. The data are not + * copied, and the client is responsible for releasing and destroying + * them _after_ the corresponding call to @FT_Done_Face. + * + * Otherwise, if the @FT_OPEN_STREAM bit is set, assume that a custom + * input stream `stream` is used. + * + * Otherwise, if the @FT_OPEN_PATHNAME bit is set, assume that this is a + * normal file and use `pathname` to open it. + * + * If the @FT_OPEN_DRIVER bit is set, @FT_Open_Face only tries to open + * the file with the driver whose handler is in `driver`. + * + * If the @FT_OPEN_PARAMS bit is set, the parameters given by + * `num_params` and `params` is used. They are ignored otherwise. + * + * Ideally, both the `pathname` and `params` fields should be tagged as + * 'const'; this is missing for API backward compatibility. In other + * words, applications should treat them as read-only. + */ typedef struct FT_Open_Args_ { FT_UInt flags; @@ -2147,34 +2127,37 @@ FT_BEGIN_HEADER } FT_Open_Args; - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_New_Face */ - /* */ - /* <Description> */ - /* Call @FT_Open_Face to open a font by its pathname. */ - /* */ - /* <InOut> */ - /* library :: A handle to the library resource. */ - /* */ - /* <Input> */ - /* pathname :: A path to the font file. */ - /* */ - /* face_index :: See @FT_Open_Face for a detailed description of this */ - /* parameter. */ - /* */ - /* <Output> */ - /* aface :: A handle to a new face object. If `face_index' is */ - /* greater than or equal to zero, it must be non-NULL. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* Use @FT_Done_Face to destroy the created @FT_Face object (along */ - /* with its slot and sizes). */ - /* */ + /************************************************************************** + * + * @function: + * FT_New_Face + * + * @description: + * Call @FT_Open_Face to open a font by its pathname. + * + * @inout: + * library :: + * A handle to the library resource. + * + * @input: + * pathname :: + * A path to the font file. + * + * face_index :: + * See @FT_Open_Face for a detailed description of this parameter. + * + * @output: + * aface :: + * A handle to a new face object. If `face_index` is greater than or + * equal to zero, it must be non-`NULL`. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * Use @FT_Done_Face to destroy the created @FT_Face object (along with + * its slot and sizes). + */ FT_EXPORT( FT_Error ) FT_New_Face( FT_Library library, const char* filepathname, @@ -2182,36 +2165,39 @@ FT_BEGIN_HEADER FT_Face *aface ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_New_Memory_Face */ - /* */ - /* <Description> */ - /* Call @FT_Open_Face to open a font that has been loaded into */ - /* memory. */ - /* */ - /* <InOut> */ - /* library :: A handle to the library resource. */ - /* */ - /* <Input> */ - /* file_base :: A pointer to the beginning of the font data. */ - /* */ - /* file_size :: The size of the memory chunk used by the font data. */ - /* */ - /* face_index :: See @FT_Open_Face for a detailed description of this */ - /* parameter. */ - /* */ - /* <Output> */ - /* aface :: A handle to a new face object. If `face_index' is */ - /* greater than or equal to zero, it must be non-NULL. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* You must not deallocate the memory before calling @FT_Done_Face. */ - /* */ + /************************************************************************** + * + * @function: + * FT_New_Memory_Face + * + * @description: + * Call @FT_Open_Face to open a font that has been loaded into memory. + * + * @inout: + * library :: + * A handle to the library resource. + * + * @input: + * file_base :: + * A pointer to the beginning of the font data. + * + * file_size :: + * The size of the memory chunk used by the font data. + * + * face_index :: + * See @FT_Open_Face for a detailed description of this parameter. + * + * @output: + * aface :: + * A handle to a new face object. If `face_index` is greater than or + * equal to zero, it must be non-`NULL`. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * You must not deallocate the memory before calling @FT_Done_Face. + */ FT_EXPORT( FT_Error ) FT_New_Memory_Face( FT_Library library, const FT_Byte* file_base, @@ -2220,147 +2206,143 @@ FT_BEGIN_HEADER FT_Face *aface ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Open_Face */ - /* */ - /* <Description> */ - /* Create a face object from a given resource described by */ - /* @FT_Open_Args. */ - /* */ - /* <InOut> */ - /* library :: A handle to the library resource. */ - /* */ - /* <Input> */ - /* args :: A pointer to an `FT_Open_Args' structure that must */ - /* be filled by the caller. */ - /* */ - /* face_index :: This field holds two different values. Bits 0-15 */ - /* are the index of the face in the font file (starting */ - /* with value~0). Set it to~0 if there is only one */ - /* face in the font file. */ - /* */ - /* [Since 2.6.1] Bits 16-30 are relevant to GX and */ - /* OpenType variation fonts only, specifying the named */ - /* instance index for the current face index (starting */ - /* with value~1; value~0 makes FreeType ignore named */ - /* instances). For non-variation fonts, bits 16-30 are */ - /* ignored. Assuming that you want to access the third */ - /* named instance in face~4, `face_index' should be set */ - /* to 0x00030004. If you want to access face~4 without */ - /* variation handling, simply set `face_index' to */ - /* value~4. */ - /* */ - /* `FT_Open_Face' and its siblings can be used to */ - /* quickly check whether the font format of a given */ - /* font resource is supported by FreeType. In general, */ - /* if the `face_index' argument is negative, the */ - /* function's return value is~0 if the font format is */ - /* recognized, or non-zero otherwise. The function */ - /* allocates a more or less empty face handle in */ - /* `*aface' (if `aface' isn't NULL); the only two */ - /* useful fields in this special case are */ - /* `face->num_faces' and `face->style_flags'. For any */ - /* negative value of `face_index', `face->num_faces' */ - /* gives the number of faces within the font file. For */ - /* the negative value `-(N+1)' (with `N' a non-negative */ - /* 16-bit value), bits 16-30 in `face->style_flags' */ - /* give the number of named instances in face `N' if we */ - /* have a variation font (or zero otherwise). After */ - /* examination, the returned @FT_Face structure should */ - /* be deallocated with a call to @FT_Done_Face. */ - /* */ - /* <Output> */ - /* aface :: A handle to a new face object. If `face_index' is */ - /* greater than or equal to zero, it must be non-NULL. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* Unlike FreeType 1.x, this function automatically creates a glyph */ - /* slot for the face object that can be accessed directly through */ - /* `face->glyph'. */ - /* */ - /* Each new face object created with this function also owns a */ - /* default @FT_Size object, accessible as `face->size'. */ - /* */ - /* One @FT_Library instance can have multiple face objects, this is, */ - /* @FT_Open_Face and its siblings can be called multiple times using */ - /* the same `library' argument. */ - /* */ - /* See the discussion of reference counters in the description of */ - /* @FT_Reference_Face. */ - /* */ - /* To loop over all faces, use code similar to the following snippet */ - /* (omitting the error handling). */ - /* */ - /* { */ - /* ... */ - /* FT_Face face; */ - /* FT_Long i, num_faces; */ - /* */ - /* */ - /* error = FT_Open_Face( library, args, -1, &face ); */ - /* if ( error ) { ... } */ - /* */ - /* num_faces = face->num_faces; */ - /* FT_Done_Face( face ); */ - /* */ - /* for ( i = 0; i < num_faces; i++ ) */ - /* { */ - /* ... */ - /* error = FT_Open_Face( library, args, i, &face ); */ - /* ... */ - /* FT_Done_Face( face ); */ - /* ... */ - /* } */ - /* } */ - /* */ - /* To loop over all valid values for `face_index', use something */ - /* similar to the following snippet, again without error handling. */ - /* The code accesses all faces immediately (thus only a single call */ - /* of `FT_Open_Face' within the do-loop), with and without named */ - /* instances. */ - /* */ - /* { */ - /* ... */ - /* FT_Face face; */ - /* */ - /* FT_Long num_faces = 0; */ - /* FT_Long num_instances = 0; */ - /* */ - /* FT_Long face_idx = 0; */ - /* FT_Long instance_idx = 0; */ - /* */ - /* */ - /* do */ - /* { */ - /* FT_Long id = ( instance_idx << 16 ) + face_idx; */ - /* */ - /* */ - /* error = FT_Open_Face( library, args, id, &face ); */ - /* if ( error ) { ... } */ - /* */ - /* num_faces = face->num_faces; */ - /* num_instances = face->style_flags >> 16; */ - /* */ - /* ... */ - /* */ - /* FT_Done_Face( face ); */ - /* */ - /* if ( instance_idx < num_instances ) */ - /* instance_idx++; */ - /* else */ - /* { */ - /* face_idx++; */ - /* instance_idx = 0; */ - /* } */ - /* */ - /* } while ( face_idx < num_faces ) */ - /* } */ - /* */ + /************************************************************************** + * + * @function: + * FT_Open_Face + * + * @description: + * Create a face object from a given resource described by @FT_Open_Args. + * + * @inout: + * library :: + * A handle to the library resource. + * + * @input: + * args :: + * A pointer to an `FT_Open_Args` structure that must be filled by the + * caller. + * + * face_index :: + * This field holds two different values. Bits 0-15 are the index of + * the face in the font file (starting with value~0). Set it to~0 if + * there is only one face in the font file. + * + * [Since 2.6.1] Bits 16-30 are relevant to GX and OpenType variation + * fonts only, specifying the named instance index for the current face + * index (starting with value~1; value~0 makes FreeType ignore named + * instances). For non-variation fonts, bits 16-30 are ignored. + * Assuming that you want to access the third named instance in face~4, + * `face_index` should be set to 0x00030004. If you want to access + * face~4 without variation handling, simply set `face_index` to + * value~4. + * + * `FT_Open_Face` and its siblings can be used to quickly check whether + * the font format of a given font resource is supported by FreeType. + * In general, if the `face_index` argument is negative, the function's + * return value is~0 if the font format is recognized, or non-zero + * otherwise. The function allocates a more or less empty face handle + * in `*aface` (if `aface` isn't `NULL`); the only two useful fields in + * this special case are `face->num_faces` and `face->style_flags`. + * For any negative value of `face_index`, `face->num_faces` gives the + * number of faces within the font file. For the negative value + * '-(N+1)' (with 'N' a non-negative 16-bit value), bits 16-30 in + * `face->style_flags` give the number of named instances in face 'N' + * if we have a variation font (or zero otherwise). After examination, + * the returned @FT_Face structure should be deallocated with a call to + * @FT_Done_Face. + * + * @output: + * aface :: + * A handle to a new face object. If `face_index` is greater than or + * equal to zero, it must be non-`NULL`. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * Unlike FreeType 1.x, this function automatically creates a glyph slot + * for the face object that can be accessed directly through + * `face->glyph`. + * + * Each new face object created with this function also owns a default + * @FT_Size object, accessible as `face->size`. + * + * One @FT_Library instance can have multiple face objects, this is, + * @FT_Open_Face and its siblings can be called multiple times using the + * same `library` argument. + * + * See the discussion of reference counters in the description of + * @FT_Reference_Face. + * + * @example: + * To loop over all faces, use code similar to the following snippet + * (omitting the error handling). + * + * ``` + * ... + * FT_Face face; + * FT_Long i, num_faces; + * + * + * error = FT_Open_Face( library, args, -1, &face ); + * if ( error ) { ... } + * + * num_faces = face->num_faces; + * FT_Done_Face( face ); + * + * for ( i = 0; i < num_faces; i++ ) + * { + * ... + * error = FT_Open_Face( library, args, i, &face ); + * ... + * FT_Done_Face( face ); + * ... + * } + * ``` + * + * To loop over all valid values for `face_index`, use something similar + * to the following snippet, again without error handling. The code + * accesses all faces immediately (thus only a single call of + * `FT_Open_Face` within the do-loop), with and without named instances. + * + * ``` + * ... + * FT_Face face; + * + * FT_Long num_faces = 0; + * FT_Long num_instances = 0; + * + * FT_Long face_idx = 0; + * FT_Long instance_idx = 0; + * + * + * do + * { + * FT_Long id = ( instance_idx << 16 ) + face_idx; + * + * + * error = FT_Open_Face( library, args, id, &face ); + * if ( error ) { ... } + * + * num_faces = face->num_faces; + * num_instances = face->style_flags >> 16; + * + * ... + * + * FT_Done_Face( face ); + * + * if ( instance_idx < num_instances ) + * instance_idx++; + * else + * { + * face_idx++; + * instance_idx = 0; + * } + * + * } while ( face_idx < num_faces ) + * ``` + */ FT_EXPORT( FT_Error ) FT_Open_Face( FT_Library library, const FT_Open_Args* args, @@ -2368,204 +2350,208 @@ FT_BEGIN_HEADER FT_Face *aface ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Attach_File */ - /* */ - /* <Description> */ - /* Call @FT_Attach_Stream to attach a file. */ - /* */ - /* <InOut> */ - /* face :: The target face object. */ - /* */ - /* <Input> */ - /* filepathname :: The pathname. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Attach_File + * + * @description: + * Call @FT_Attach_Stream to attach a file. + * + * @inout: + * face :: + * The target face object. + * + * @input: + * filepathname :: + * The pathname. + * + * @return: + * FreeType error code. 0~means success. + */ FT_EXPORT( FT_Error ) FT_Attach_File( FT_Face face, const char* filepathname ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Attach_Stream */ - /* */ - /* <Description> */ - /* `Attach' data to a face object. Normally, this is used to read */ - /* additional information for the face object. For example, you can */ - /* attach an AFM file that comes with a Type~1 font to get the */ - /* kerning values and other metrics. */ - /* */ - /* <InOut> */ - /* face :: The target face object. */ - /* */ - /* <Input> */ - /* parameters :: A pointer to @FT_Open_Args that must be filled by */ - /* the caller. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* The meaning of the `attach' (i.e., what really happens when the */ - /* new file is read) is not fixed by FreeType itself. It really */ - /* depends on the font format (and thus the font driver). */ - /* */ - /* Client applications are expected to know what they are doing */ - /* when invoking this function. Most drivers simply do not implement */ - /* file or stream attachments. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Attach_Stream + * + * @description: + * 'Attach' data to a face object. Normally, this is used to read + * additional information for the face object. For example, you can + * attach an AFM file that comes with a Type~1 font to get the kerning + * values and other metrics. + * + * @inout: + * face :: + * The target face object. + * + * @input: + * parameters :: + * A pointer to @FT_Open_Args that must be filled by the caller. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * The meaning of the 'attach' (i.e., what really happens when the new + * file is read) is not fixed by FreeType itself. It really depends on + * the font format (and thus the font driver). + * + * Client applications are expected to know what they are doing when + * invoking this function. Most drivers simply do not implement file or + * stream attachments. + */ FT_EXPORT( FT_Error ) FT_Attach_Stream( FT_Face face, FT_Open_Args* parameters ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Reference_Face */ - /* */ - /* <Description> */ - /* A counter gets initialized to~1 at the time an @FT_Face structure */ - /* is created. This function increments the counter. @FT_Done_Face */ - /* then only destroys a face if the counter is~1, otherwise it simply */ - /* decrements the counter. */ - /* */ - /* This function helps in managing life-cycles of structures that */ - /* reference @FT_Face objects. */ - /* */ - /* <Input> */ - /* face :: A handle to a target face object. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Since> */ - /* 2.4.2 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Reference_Face + * + * @description: + * A counter gets initialized to~1 at the time an @FT_Face structure is + * created. This function increments the counter. @FT_Done_Face then + * only destroys a face if the counter is~1, otherwise it simply + * decrements the counter. + * + * This function helps in managing life-cycles of structures that + * reference @FT_Face objects. + * + * @input: + * face :: + * A handle to a target face object. + * + * @return: + * FreeType error code. 0~means success. + * + * @since: + * 2.4.2 + */ FT_EXPORT( FT_Error ) FT_Reference_Face( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Done_Face */ - /* */ - /* <Description> */ - /* Discard a given face object, as well as all of its child slots and */ - /* sizes. */ - /* */ - /* <Input> */ - /* face :: A handle to a target face object. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* See the discussion of reference counters in the description of */ - /* @FT_Reference_Face. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Done_Face + * + * @description: + * Discard a given face object, as well as all of its child slots and + * sizes. + * + * @input: + * face :: + * A handle to a target face object. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * See the discussion of reference counters in the description of + * @FT_Reference_Face. + */ FT_EXPORT( FT_Error ) FT_Done_Face( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Select_Size */ - /* */ - /* <Description> */ - /* Select a bitmap strike. To be more precise, this function sets */ - /* the scaling factors of the active @FT_Size object in a face so */ - /* that bitmaps from this particular strike are taken by */ - /* @FT_Load_Glyph and friends. */ - /* */ - /* <InOut> */ - /* face :: A handle to a target face object. */ - /* */ - /* <Input> */ - /* strike_index :: The index of the bitmap strike in the */ - /* `available_sizes' field of @FT_FaceRec structure. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* For bitmaps embedded in outline fonts it is common that only a */ - /* subset of the available glyphs at a given ppem value is available. */ - /* FreeType silently uses outlines if there is no bitmap for a given */ - /* glyph index. */ - /* */ - /* For GX and OpenType variation fonts, a bitmap strike makes sense */ - /* only if the default instance is active (this is, no glyph */ - /* variation takes place); otherwise, FreeType simply ignores bitmap */ - /* strikes. The same is true for all named instances that are */ - /* different from the default instance. */ - /* */ - /* Don't use this function if you are using the FreeType cache API. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Select_Size + * + * @description: + * Select a bitmap strike. To be more precise, this function sets the + * scaling factors of the active @FT_Size object in a face so that + * bitmaps from this particular strike are taken by @FT_Load_Glyph and + * friends. + * + * @inout: + * face :: + * A handle to a target face object. + * + * @input: + * strike_index :: + * The index of the bitmap strike in the `available_sizes` field of + * @FT_FaceRec structure. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * For bitmaps embedded in outline fonts it is common that only a subset + * of the available glyphs at a given ppem value is available. FreeType + * silently uses outlines if there is no bitmap for a given glyph index. + * + * For GX and OpenType variation fonts, a bitmap strike makes sense only + * if the default instance is active (this is, no glyph variation takes + * place); otherwise, FreeType simply ignores bitmap strikes. The same + * is true for all named instances that are different from the default + * instance. + * + * Don't use this function if you are using the FreeType cache API. + */ FT_EXPORT( FT_Error ) FT_Select_Size( FT_Face face, FT_Int strike_index ); - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_Size_Request_Type */ - /* */ - /* <Description> */ - /* An enumeration type that lists the supported size request types, */ - /* i.e., what input size (in font units) maps to the requested output */ - /* size (in pixels, as computed from the arguments of */ - /* @FT_Size_Request). */ - /* */ - /* <Values> */ - /* FT_SIZE_REQUEST_TYPE_NOMINAL :: */ - /* The nominal size. The `units_per_EM' field of @FT_FaceRec is */ - /* used to determine both scaling values. */ - /* */ - /* This is the standard scaling found in most applications. In */ - /* particular, use this size request type for TrueType fonts if */ - /* they provide optical scaling or something similar. Note, */ - /* however, that `units_per_EM' is a rather abstract value which */ - /* bears no relation to the actual size of the glyphs in a font. */ - /* */ - /* FT_SIZE_REQUEST_TYPE_REAL_DIM :: */ - /* The real dimension. The sum of the `ascender' and (minus of) */ - /* the `descender' fields of @FT_FaceRec is used to determine both */ - /* scaling values. */ - /* */ - /* FT_SIZE_REQUEST_TYPE_BBOX :: */ - /* The font bounding box. The width and height of the `bbox' field */ - /* of @FT_FaceRec are used to determine the horizontal and vertical */ - /* scaling value, respectively. */ - /* */ - /* FT_SIZE_REQUEST_TYPE_CELL :: */ - /* The `max_advance_width' field of @FT_FaceRec is used to */ - /* determine the horizontal scaling value; the vertical scaling */ - /* value is determined the same way as */ - /* @FT_SIZE_REQUEST_TYPE_REAL_DIM does. Finally, both scaling */ - /* values are set to the smaller one. This type is useful if you */ - /* want to specify the font size for, say, a window of a given */ - /* dimension and 80x24 cells. */ - /* */ - /* FT_SIZE_REQUEST_TYPE_SCALES :: */ - /* Specify the scaling values directly. */ - /* */ - /* <Note> */ - /* The above descriptions only apply to scalable formats. For bitmap */ - /* formats, the behaviour is up to the driver. */ - /* */ - /* See the note section of @FT_Size_Metrics if you wonder how size */ - /* requesting relates to scaling values. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_Size_Request_Type + * + * @description: + * An enumeration type that lists the supported size request types, i.e., + * what input size (in font units) maps to the requested output size (in + * pixels, as computed from the arguments of @FT_Size_Request). + * + * @values: + * FT_SIZE_REQUEST_TYPE_NOMINAL :: + * The nominal size. The `units_per_EM` field of @FT_FaceRec is used + * to determine both scaling values. + * + * This is the standard scaling found in most applications. In + * particular, use this size request type for TrueType fonts if they + * provide optical scaling or something similar. Note, however, that + * `units_per_EM` is a rather abstract value which bears no relation to + * the actual size of the glyphs in a font. + * + * FT_SIZE_REQUEST_TYPE_REAL_DIM :: + * The real dimension. The sum of the `ascender` and (minus of) the + * `descender` fields of @FT_FaceRec is used to determine both scaling + * values. + * + * FT_SIZE_REQUEST_TYPE_BBOX :: + * The font bounding box. The width and height of the `bbox` field of + * @FT_FaceRec are used to determine the horizontal and vertical + * scaling value, respectively. + * + * FT_SIZE_REQUEST_TYPE_CELL :: + * The `max_advance_width` field of @FT_FaceRec is used to determine + * the horizontal scaling value; the vertical scaling value is + * determined the same way as @FT_SIZE_REQUEST_TYPE_REAL_DIM does. + * Finally, both scaling values are set to the smaller one. This type + * is useful if you want to specify the font size for, say, a window of + * a given dimension and 80x24 cells. + * + * FT_SIZE_REQUEST_TYPE_SCALES :: + * Specify the scaling values directly. + * + * @note: + * The above descriptions only apply to scalable formats. For bitmap + * formats, the behaviour is up to the driver. + * + * See the note section of @FT_Size_Metrics if you wonder how size + * requesting relates to scaling values. + */ typedef enum FT_Size_Request_Type_ { FT_SIZE_REQUEST_TYPE_NOMINAL, @@ -2579,42 +2565,45 @@ FT_BEGIN_HEADER } FT_Size_Request_Type; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Size_RequestRec */ - /* */ - /* <Description> */ - /* A structure to model a size request. */ - /* */ - /* <Fields> */ - /* type :: See @FT_Size_Request_Type. */ - /* */ - /* width :: The desired width, given as a 26.6 fractional */ - /* point value (with 72pt = 1in). */ - /* */ - /* height :: The desired height, given as a 26.6 fractional */ - /* point value (with 72pt = 1in). */ - /* */ - /* horiResolution :: The horizontal resolution (dpi, i.e., pixels per */ - /* inch). If set to zero, `width' is treated as a */ - /* 26.6 fractional *pixel* value, which gets */ - /* internally rounded to an integer. */ - /* */ - /* vertResolution :: The vertical resolution (dpi, i.e., pixels per */ - /* inch). If set to zero, `height' is treated as a */ - /* 26.6 fractional *pixel* value, which gets */ - /* internally rounded to an integer. */ - /* */ - /* <Note> */ - /* If `width' is zero, the horizontal scaling value is set equal */ - /* to the vertical scaling value, and vice versa. */ - /* */ - /* If `type' is FT_SIZE_REQUEST_TYPE_SCALES, `width' and `height' are */ - /* interpreted directly as 16.16 fractional scaling values, without */ - /* any further modification, and both `horiResolution' and */ - /* `vertResolution' are ignored. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Size_RequestRec + * + * @description: + * A structure to model a size request. + * + * @fields: + * type :: + * See @FT_Size_Request_Type. + * + * width :: + * The desired width, given as a 26.6 fractional point value (with 72pt + * = 1in). + * + * height :: + * The desired height, given as a 26.6 fractional point value (with + * 72pt = 1in). + * + * horiResolution :: + * The horizontal resolution (dpi, i.e., pixels per inch). If set to + * zero, `width` is treated as a 26.6 fractional **pixel** value, which + * gets internally rounded to an integer. + * + * vertResolution :: + * The vertical resolution (dpi, i.e., pixels per inch). If set to + * zero, `height` is treated as a 26.6 fractional **pixel** value, + * which gets internally rounded to an integer. + * + * @note: + * If `width` is zero, the horizontal scaling value is set equal to the + * vertical scaling value, and vice versa. + * + * If `type` is `FT_SIZE_REQUEST_TYPE_SCALES`, `width` and `height` are + * interpreted directly as 16.16 fractional scaling values, without any + * further modification, and both `horiResolution` and `vertResolution` + * are ignored. + */ typedef struct FT_Size_RequestRec_ { FT_Size_Request_Type type; @@ -2626,96 +2615,102 @@ FT_BEGIN_HEADER } FT_Size_RequestRec; - /*************************************************************************/ - /* */ - /* <Struct> */ - /* FT_Size_Request */ - /* */ - /* <Description> */ - /* A handle to a size request structure. */ - /* */ + /************************************************************************** + * + * @struct: + * FT_Size_Request + * + * @description: + * A handle to a size request structure. + */ typedef struct FT_Size_RequestRec_ *FT_Size_Request; - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Request_Size */ - /* */ - /* <Description> */ - /* Resize the scale of the active @FT_Size object in a face. */ - /* */ - /* <InOut> */ - /* face :: A handle to a target face object. */ - /* */ - /* <Input> */ - /* req :: A pointer to a @FT_Size_RequestRec. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* Although drivers may select the bitmap strike matching the */ - /* request, you should not rely on this if you intend to select a */ - /* particular bitmap strike. Use @FT_Select_Size instead in that */ - /* case. */ - /* */ - /* The relation between the requested size and the resulting glyph */ - /* size is dependent entirely on how the size is defined in the */ - /* source face. The font designer chooses the final size of each */ - /* glyph relative to this size. For more information refer to */ - /* `https://www.freetype.org/freetype2/docs/glyphs/glyphs-2.html'. */ - /* */ - /* Contrary to @FT_Set_Char_Size, this function doesn't have special */ - /* code to normalize zero-valued widths, heights, or resolutions */ - /* (which lead to errors in most cases). */ - /* */ - /* Don't use this function if you are using the FreeType cache API. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Request_Size + * + * @description: + * Resize the scale of the active @FT_Size object in a face. + * + * @inout: + * face :: + * A handle to a target face object. + * + * @input: + * req :: + * A pointer to a @FT_Size_RequestRec. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * Although drivers may select the bitmap strike matching the request, + * you should not rely on this if you intend to select a particular + * bitmap strike. Use @FT_Select_Size instead in that case. + * + * The relation between the requested size and the resulting glyph size + * is dependent entirely on how the size is defined in the source face. + * The font designer chooses the final size of each glyph relative to + * this size. For more information refer to + * 'https://www.freetype.org/freetype2/docs/glyphs/glyphs-2.html'. + * + * Contrary to @FT_Set_Char_Size, this function doesn't have special code + * to normalize zero-valued widths, heights, or resolutions (which lead + * to errors in most cases). + * + * Don't use this function if you are using the FreeType cache API. + */ FT_EXPORT( FT_Error ) FT_Request_Size( FT_Face face, FT_Size_Request req ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Set_Char_Size */ - /* */ - /* <Description> */ - /* Call @FT_Request_Size to request the nominal size (in points). */ - /* */ - /* <InOut> */ - /* face :: A handle to a target face object. */ - /* */ - /* <Input> */ - /* char_width :: The nominal width, in 26.6 fractional points. */ - /* */ - /* char_height :: The nominal height, in 26.6 fractional points. */ - /* */ - /* horz_resolution :: The horizontal resolution in dpi. */ - /* */ - /* vert_resolution :: The vertical resolution in dpi. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* While this function allows fractional points as input values, the */ - /* resulting ppem value for the given resolution is always rounded to */ - /* the nearest integer. */ - /* */ - /* If either the character width or height is zero, it is set equal */ - /* to the other value. */ - /* */ - /* If either the horizontal or vertical resolution is zero, it is set */ - /* equal to the other value. */ - /* */ - /* A character width or height smaller than 1pt is set to 1pt; if */ - /* both resolution values are zero, they are set to 72dpi. */ - /* */ - /* Don't use this function if you are using the FreeType cache API. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Set_Char_Size + * + * @description: + * Call @FT_Request_Size to request the nominal size (in points). + * + * @inout: + * face :: + * A handle to a target face object. + * + * @input: + * char_width :: + * The nominal width, in 26.6 fractional points. + * + * char_height :: + * The nominal height, in 26.6 fractional points. + * + * horz_resolution :: + * The horizontal resolution in dpi. + * + * vert_resolution :: + * The vertical resolution in dpi. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * While this function allows fractional points as input values, the + * resulting ppem value for the given resolution is always rounded to the + * nearest integer. + * + * If either the character width or height is zero, it is set equal to + * the other value. + * + * If either the horizontal or vertical resolution is zero, it is set + * equal to the other value. + * + * A character width or height smaller than 1pt is set to 1pt; if both + * resolution values are zero, they are set to 72dpi. + * + * Don't use this function if you are using the FreeType cache API. + */ FT_EXPORT( FT_Error ) FT_Set_Char_Size( FT_Face face, FT_F26Dot6 char_width, @@ -2724,134 +2719,138 @@ FT_BEGIN_HEADER FT_UInt vert_resolution ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Set_Pixel_Sizes */ - /* */ - /* <Description> */ - /* Call @FT_Request_Size to request the nominal size (in pixels). */ - /* */ - /* <InOut> */ - /* face :: A handle to the target face object. */ - /* */ - /* <Input> */ - /* pixel_width :: The nominal width, in pixels. */ - /* */ - /* pixel_height :: The nominal height, in pixels. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* You should not rely on the resulting glyphs matching or being */ - /* constrained to this pixel size. Refer to @FT_Request_Size to */ - /* understand how requested sizes relate to actual sizes. */ - /* */ - /* Don't use this function if you are using the FreeType cache API. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Set_Pixel_Sizes + * + * @description: + * Call @FT_Request_Size to request the nominal size (in pixels). + * + * @inout: + * face :: + * A handle to the target face object. + * + * @input: + * pixel_width :: + * The nominal width, in pixels. + * + * pixel_height :: + * The nominal height, in pixels. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * You should not rely on the resulting glyphs matching or being + * constrained to this pixel size. Refer to @FT_Request_Size to + * understand how requested sizes relate to actual sizes. + * + * Don't use this function if you are using the FreeType cache API. + */ FT_EXPORT( FT_Error ) FT_Set_Pixel_Sizes( FT_Face face, FT_UInt pixel_width, FT_UInt pixel_height ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Load_Glyph */ - /* */ - /* <Description> */ - /* Load a glyph into the glyph slot of a face object. */ - /* */ - /* <InOut> */ - /* face :: A handle to the target face object where the glyph */ - /* is loaded. */ - /* */ - /* <Input> */ - /* glyph_index :: The index of the glyph in the font file. For */ - /* CID-keyed fonts (either in PS or in CFF format) */ - /* this argument specifies the CID value. */ - /* */ - /* load_flags :: A flag indicating what to load for this glyph. The */ - /* @FT_LOAD_XXX constants can be used to control the */ - /* glyph loading process (e.g., whether the outline */ - /* should be scaled, whether to load bitmaps or not, */ - /* whether to hint the outline, etc). */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* The loaded glyph may be transformed. See @FT_Set_Transform for */ - /* the details. */ - /* */ - /* For subsetted CID-keyed fonts, `FT_Err_Invalid_Argument' is */ - /* returned for invalid CID values (this is, for CID values that */ - /* don't have a corresponding glyph in the font). See the discussion */ - /* of the @FT_FACE_FLAG_CID_KEYED flag for more details. */ - /* */ - /* If you receive `FT_Err_Glyph_Too_Big', try getting the glyph */ - /* outline at EM size, then scale it manually and fill it as a */ - /* graphics operation. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Load_Glyph + * + * @description: + * Load a glyph into the glyph slot of a face object. + * + * @inout: + * face :: + * A handle to the target face object where the glyph is loaded. + * + * @input: + * glyph_index :: + * The index of the glyph in the font file. For CID-keyed fonts + * (either in PS or in CFF format) this argument specifies the CID + * value. + * + * load_flags :: + * A flag indicating what to load for this glyph. The @FT_LOAD_XXX + * constants can be used to control the glyph loading process (e.g., + * whether the outline should be scaled, whether to load bitmaps or + * not, whether to hint the outline, etc). + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * The loaded glyph may be transformed. See @FT_Set_Transform for the + * details. + * + * For subsetted CID-keyed fonts, `FT_Err_Invalid_Argument` is returned + * for invalid CID values (this is, for CID values that don't have a + * corresponding glyph in the font). See the discussion of the + * @FT_FACE_FLAG_CID_KEYED flag for more details. + * + * If you receive `FT_Err_Glyph_Too_Big`, try getting the glyph outline + * at EM size, then scale it manually and fill it as a graphics + * operation. + */ FT_EXPORT( FT_Error ) FT_Load_Glyph( FT_Face face, FT_UInt glyph_index, FT_Int32 load_flags ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Load_Char */ - /* */ - /* <Description> */ - /* Load a glyph into the glyph slot of a face object, accessed by its */ - /* character code. */ - /* */ - /* <InOut> */ - /* face :: A handle to a target face object where the glyph */ - /* is loaded. */ - /* */ - /* <Input> */ - /* char_code :: The glyph's character code, according to the */ - /* current charmap used in the face. */ - /* */ - /* load_flags :: A flag indicating what to load for this glyph. The */ - /* @FT_LOAD_XXX constants can be used to control the */ - /* glyph loading process (e.g., whether the outline */ - /* should be scaled, whether to load bitmaps or not, */ - /* whether to hint the outline, etc). */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* This function simply calls @FT_Get_Char_Index and @FT_Load_Glyph. */ - /* */ - /* Many fonts contain glyphs that can't be loaded by this function */ - /* since its glyph indices are not listed in any of the font's */ - /* charmaps. */ - /* */ - /* If no active cmap is set up (i.e., `face->charmap' is zero), the */ - /* call to @FT_Get_Char_Index is omitted, and the function behaves */ - /* identically to @FT_Load_Glyph. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Load_Char + * + * @description: + * Load a glyph into the glyph slot of a face object, accessed by its + * character code. + * + * @inout: + * face :: + * A handle to a target face object where the glyph is loaded. + * + * @input: + * char_code :: + * The glyph's character code, according to the current charmap used in + * the face. + * + * load_flags :: + * A flag indicating what to load for this glyph. The @FT_LOAD_XXX + * constants can be used to control the glyph loading process (e.g., + * whether the outline should be scaled, whether to load bitmaps or + * not, whether to hint the outline, etc). + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * This function simply calls @FT_Get_Char_Index and @FT_Load_Glyph. + * + * Many fonts contain glyphs that can't be loaded by this function since + * its glyph indices are not listed in any of the font's charmaps. + * + * If no active cmap is set up (i.e., `face->charmap` is zero), the call + * to @FT_Get_Char_Index is omitted, and the function behaves identically + * to @FT_Load_Glyph. + */ FT_EXPORT( FT_Error ) FT_Load_Char( FT_Face face, FT_ULong char_code, FT_Int32 load_flags ); - /************************************************************************* + /************************************************************************** * * @enum: * FT_LOAD_XXX * * @description: - * A list of bit field constants for @FT_Load_Glyph to indicate what - * kind of operations to perform during glyph loading. + * A list of bit field constants for @FT_Load_Glyph to indicate what kind + * of operations to perform during glyph loading. * * @values: * FT_LOAD_DEFAULT :: @@ -2859,15 +2858,14 @@ FT_BEGIN_HEADER * operation. In this case, the following happens: * * 1. FreeType looks for a bitmap for the glyph corresponding to the - * face's current size. If one is found, the function returns. - * The bitmap data can be accessed from the glyph slot (see note - * below). + * face's current size. If one is found, the function returns. The + * bitmap data can be accessed from the glyph slot (see note below). * * 2. If no embedded bitmap is searched for or found, FreeType looks - * for a scalable outline. If one is found, it is loaded from - * the font file, scaled to device pixels, then `hinted' to the - * pixel grid in order to optimize it. The outline data can be - * accessed from the glyph slot (see note below). + * for a scalable outline. If one is found, it is loaded from the font + * file, scaled to device pixels, then 'hinted' to the pixel grid in + * order to optimize it. The outline data can be accessed from the + * glyph slot (see note below). * * Note that by default the glyph loader doesn't render outlines into * bitmaps. The following flags are used to modify this default @@ -2879,14 +2877,14 @@ FT_BEGIN_HEADER * This flag implies @FT_LOAD_NO_HINTING and @FT_LOAD_NO_BITMAP, and * unsets @FT_LOAD_RENDER. * - * If the font is `tricky' (see @FT_FACE_FLAG_TRICKY for more), using - * FT_LOAD_NO_SCALE usually yields meaningless outlines because the - * subglyphs must be scaled and positioned with hinting instructions. - * This can be solved by loading the font without FT_LOAD_NO_SCALE and - * setting the character size to `font->units_per_EM'. + * If the font is 'tricky' (see @FT_FACE_FLAG_TRICKY for more), using + * `FT_LOAD_NO_SCALE` usually yields meaningless outlines because the + * subglyphs must be scaled and positioned with hinting instructions. + * This can be solved by loading the font without `FT_LOAD_NO_SCALE` + * and setting the character size to `font->units_per_EM`. * * FT_LOAD_NO_HINTING :: - * Disable hinting. This generally generates `blurrier' bitmap glyphs + * Disable hinting. This generally generates 'blurrier' bitmap glyphs * when the glyph are rendered in any of the anti-aliased modes. See * also the note below. * @@ -2907,34 +2905,37 @@ FT_BEGIN_HEADER * * FT_LOAD_VERTICAL_LAYOUT :: * Load the glyph for vertical text layout. In particular, the - * `advance' value in the @FT_GlyphSlotRec structure is set to the - * `vertAdvance' value of the `metrics' field. + * `advance` value in the @FT_GlyphSlotRec structure is set to the + * `vertAdvance` value of the `metrics` field. * - * In case @FT_HAS_VERTICAL doesn't return true, you shouldn't use - * this flag currently. Reason is that in this case vertical metrics - * get synthesized, and those values are not always consistent across + * In case @FT_HAS_VERTICAL doesn't return true, you shouldn't use this + * flag currently. Reason is that in this case vertical metrics get + * synthesized, and those values are not always consistent across * various font formats. * * FT_LOAD_FORCE_AUTOHINT :: - * Prefer the auto-hinter over the font's native hinter. See also - * the note below. + * Prefer the auto-hinter over the font's native hinter. See also the + * note below. * * FT_LOAD_PEDANTIC :: * Make the font driver perform pedantic verifications during glyph - * loading. This is mostly used to detect broken glyphs in fonts. - * By default, FreeType tries to handle broken fonts also. + * loading and hinting. This is mostly used to detect broken glyphs in + * fonts. By default, FreeType tries to handle broken fonts also. * * In particular, errors from the TrueType bytecode engine are not - * passed to the application if this flag is not set; this might - * result in partially hinted or distorted glyphs in case a glyph's - * bytecode is buggy. + * passed to the application if this flag is not set; this might result + * in partially hinted or distorted glyphs in case a glyph's bytecode + * is buggy. * * FT_LOAD_NO_RECURSE :: - * Don't load composite glyphs recursively. Instead, the font - * driver should set the `num_subglyph' and `subglyphs' values of - * the glyph slot accordingly, and set `glyph->format' to - * @FT_GLYPH_FORMAT_COMPOSITE. The description of subglyphs can - * then be accessed with @FT_Get_SubGlyph_Info. + * Don't load composite glyphs recursively. Instead, the font driver + * fills the `num_subglyph` and `subglyphs` values of the glyph slot; + * it also sets `glyph->format` to @FT_GLYPH_FORMAT_COMPOSITE. The + * description of subglyphs can then be accessed with + * @FT_Get_SubGlyph_Info. + * + * Don't use this flag for retrieving metrics information since some + * font drivers only return rudimentary data. * * This flag implies @FT_LOAD_NO_SCALE and @FT_LOAD_IGNORE_TRANSFORM. * @@ -2951,23 +2952,35 @@ FT_BEGIN_HEADER * monochrome-optimized hinting algorithm is used. * * FT_LOAD_LINEAR_DESIGN :: - * Keep `linearHoriAdvance' and `linearVertAdvance' fields of - * @FT_GlyphSlotRec in font units. See @FT_GlyphSlotRec for - * details. + * Keep `linearHoriAdvance` and `linearVertAdvance` fields of + * @FT_GlyphSlotRec in font units. See @FT_GlyphSlotRec for details. * * FT_LOAD_NO_AUTOHINT :: * Disable the auto-hinter. See also the note below. * * FT_LOAD_COLOR :: + * Load colored glyphs. There are slight differences depending on the + * font format. + * * [Since 2.5] Load embedded color bitmap images. The resulting color - * bitmaps, if available, will have the @FT_PIXEL_MODE_BGRA format. - * If the flag is not set and color bitmaps are found, they are - * converted to 256-level gray bitmaps transparently, using the - * @FT_PIXEL_MODE_GRAY format. + * bitmaps, if available, will have the @FT_PIXEL_MODE_BGRA format, + * with pre-multiplied color channels. If the flag is not set and + * color bitmaps are found, they are converted to 256-level gray + * bitmaps, using the @FT_PIXEL_MODE_GRAY format. + * + * [Since 2.10, experimental] If the glyph index contains an entry in + * the face's 'COLR' table with a 'CPAL' palette table (as defined in + * the OpenType specification), make @FT_Render_Glyph provide a default + * blending of the color glyph layers associated with the glyph index, + * using the same bitmap format as embedded color bitmap images. This + * is mainly for convenience; for full control of color layers use + * @FT_Get_Color_Glyph_Layer and FreeType's color functions like + * @FT_Palette_Select instead of setting @FT_LOAD_COLOR for rendering + * so that the client application can handle blending by itself. * * FT_LOAD_COMPUTE_METRICS :: - * [Since 2.6.1] Compute glyph metrics from the glyph data, without - * the use of bundled metrics tables (for example, the `hdmx' table in + * [Since 2.6.1] Compute glyph metrics from the glyph data, without the + * use of bundled metrics tables (for example, the 'hdmx' table in * TrueType fonts). This flag is mainly used by font validating or * font editing applications, which need to ignore, verify, or edit * those tables. @@ -2976,9 +2989,9 @@ FT_BEGIN_HEADER * * FT_LOAD_BITMAP_METRICS_ONLY :: * [Since 2.7.1] Request loading of the metrics and bitmap image - * information of a (possibly embedded) bitmap glyph without - * allocating or copying the bitmap image data itself. No effect if - * the target glyph is not a bitmap image. + * information of a (possibly embedded) bitmap glyph without allocating + * or copying the bitmap image data itself. No effect if the target + * glyph is not a bitmap image. * * This flag unsets @FT_LOAD_RENDER. * @@ -2993,8 +3006,8 @@ FT_BEGIN_HEADER * @FT_FACE_FLAG_HINTER) is preferred over the auto-hinter. You can * disable hinting by setting @FT_LOAD_NO_HINTING or change the * precedence by setting @FT_LOAD_FORCE_AUTOHINT. You can also set - * @FT_LOAD_NO_AUTOHINT in case you don't want the auto-hinter to be - * used at all. + * @FT_LOAD_NO_AUTOHINT in case you don't want the auto-hinter to be used + * at all. * * See the description of @FT_FACE_FLAG_TRICKY for a special exception * (affecting only a handful of Asian fonts). @@ -3005,7 +3018,7 @@ FT_BEGIN_HEADER * Note that the auto-hinter needs a valid Unicode cmap (either a native * one or synthesized by FreeType) for producing correct results. If a * font provides an incorrect mapping (for example, assigning the - * character code U+005A, LATIN CAPITAL LETTER Z, to a glyph depicting a + * character code U+005A, LATIN CAPITAL LETTER~Z, to a glyph depicting a * mathematical integral sign), the auto-hinter might produce useless * results. * @@ -3025,7 +3038,7 @@ FT_BEGIN_HEADER #define FT_LOAD_MONOCHROME ( 1L << 12 ) #define FT_LOAD_LINEAR_DESIGN ( 1L << 13 ) #define FT_LOAD_NO_AUTOHINT ( 1L << 15 ) - /* Bits 16-19 are used by `FT_LOAD_TARGET_' */ + /* Bits 16-19 are used by `FT_LOAD_TARGET_` */ #define FT_LOAD_COLOR ( 1L << 20 ) #define FT_LOAD_COMPUTE_METRICS ( 1L << 21 ) #define FT_LOAD_BITMAP_METRICS_ONLY ( 1L << 22 ) @@ -3044,19 +3057,17 @@ FT_BEGIN_HEADER * * @description: * A list of values to select a specific hinting algorithm for the - * hinter. You should OR one of these values to your `load_flags' - * when calling @FT_Load_Glyph. + * hinter. You should OR one of these values to your `load_flags` when + * calling @FT_Load_Glyph. * - * Note that a font's native hinters may ignore the hinting algorithm - * you have specified (e.g., the TrueType bytecode interpreter). You - * can set @FT_LOAD_FORCE_AUTOHINT to ensure that the auto-hinter is - * used. + * Note that a font's native hinters may ignore the hinting algorithm you + * have specified (e.g., the TrueType bytecode interpreter). You can set + * @FT_LOAD_FORCE_AUTOHINT to ensure that the auto-hinter is used. * * @values: * FT_LOAD_TARGET_NORMAL :: * The default hinting algorithm, optimized for standard gray-level - * rendering. For monochrome output, use @FT_LOAD_TARGET_MONO - * instead. + * rendering. For monochrome output, use @FT_LOAD_TARGET_MONO instead. * * FT_LOAD_TARGET_LIGHT :: * A lighter hinting algorithm for gray-level modes. Many generated @@ -3069,13 +3080,13 @@ FT_BEGIN_HEADER * auto-hinter. * * Advance widths are rounded to integer values; however, using the - * `lsb_delta' and `rsb_delta' fields of @FT_GlyphSlotRec, it is + * `lsb_delta` and `rsb_delta` fields of @FT_GlyphSlotRec, it is * possible to get fractional advance widths for subpixel positioning * (which is recommended to use). * - * If configuration option AF_CONFIG_OPTION_TT_SIZE_METRICS is active, - * TrueType-like metrics are used to make this mode behave similarly - * as in unpatched FreeType versions between 2.4.6 and 2.7.1 + * If configuration option `AF_CONFIG_OPTION_TT_SIZE_METRICS` is + * active, TrueType-like metrics are used to make this mode behave + * similarly as in unpatched FreeType versions between 2.4.6 and 2.7.1 * (inclusive). * * FT_LOAD_TARGET_MONO :: @@ -3083,6 +3094,12 @@ FT_BEGIN_HEADER * output. The result is probably unpleasant if the glyph is rendered * in non-monochrome modes. * + * Note that for outline fonts only the TrueType font driver has proper + * monochrome hinting support, provided the TTFs contain hints for B/W + * rendering (which most fonts no longer provide). If these conditions + * are not met it is very likely that you get ugly results at smaller + * sizes. + * * FT_LOAD_TARGET_LCD :: * A variant of @FT_LOAD_TARGET_LIGHT optimized for horizontally * decimated LCD displays. @@ -3092,25 +3109,25 @@ FT_BEGIN_HEADER * decimated LCD displays. * * @note: - * You should use only _one_ of the FT_LOAD_TARGET_XXX values in your - * `load_flags'. They can't be ORed. + * You should use only _one_ of the `FT_LOAD_TARGET_XXX` values in your + * `load_flags`. They can't be ORed. * * If @FT_LOAD_RENDER is also set, the glyph is rendered in the * corresponding mode (i.e., the mode that matches the used algorithm - * best). An exception is FT_LOAD_TARGET_MONO since it implies + * best). An exception is `FT_LOAD_TARGET_MONO` since it implies * @FT_LOAD_MONOCHROME. * * You can use a hinting algorithm that doesn't correspond to the same - * rendering mode. As an example, it is possible to use the `light' + * rendering mode. As an example, it is possible to use the 'light' * hinting algorithm and have the results rendered in horizontal LCD * pixel mode, with code like * - * { - * FT_Load_Glyph( face, glyph_index, - * load_flags | FT_LOAD_TARGET_LIGHT ); + * ``` + * FT_Load_Glyph( face, glyph_index, + * load_flags | FT_LOAD_TARGET_LIGHT ); * - * FT_Render_Glyph( face->glyph, FT_RENDER_MODE_LCD ); - * } + * FT_Render_Glyph( face->glyph, FT_RENDER_MODE_LCD ); + * ``` * * In general, you should stick with one rendering mode. For example, * switching between @FT_LOAD_TARGET_NORMAL and @FT_LOAD_TARGET_MONO @@ -3142,98 +3159,98 @@ FT_BEGIN_HEADER #define FT_LOAD_TARGET_MODE( x ) ( (FT_Render_Mode)( ( (x) >> 16 ) & 15 ) ) - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Set_Transform */ - /* */ - /* <Description> */ - /* Set the transformation that is applied to glyph images when they */ - /* are loaded into a glyph slot through @FT_Load_Glyph. */ - /* */ - /* <InOut> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Input> */ - /* matrix :: A pointer to the transformation's 2x2 matrix. Use NULL */ - /* for the identity matrix. */ - /* delta :: A pointer to the translation vector. Use NULL for the */ - /* null vector. */ - /* */ - /* <Note> */ - /* The transformation is only applied to scalable image formats after */ - /* the glyph has been loaded. It means that hinting is unaltered by */ - /* the transformation and is performed on the character size given in */ - /* the last call to @FT_Set_Char_Size or @FT_Set_Pixel_Sizes. */ - /* */ - /* Note that this also transforms the `face.glyph.advance' field, but */ - /* *not* the values in `face.glyph.metrics'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Set_Transform + * + * @description: + * Set the transformation that is applied to glyph images when they are + * loaded into a glyph slot through @FT_Load_Glyph. + * + * @inout: + * face :: + * A handle to the source face object. + * + * @input: + * matrix :: + * A pointer to the transformation's 2x2 matrix. Use `NULL` for the + * identity matrix. + * delta :: + * A pointer to the translation vector. Use `NULL` for the null vector. + * + * @note: + * The transformation is only applied to scalable image formats after the + * glyph has been loaded. It means that hinting is unaltered by the + * transformation and is performed on the character size given in the + * last call to @FT_Set_Char_Size or @FT_Set_Pixel_Sizes. + * + * Note that this also transforms the `face.glyph.advance` field, but + * **not** the values in `face.glyph.metrics`. + */ FT_EXPORT( void ) FT_Set_Transform( FT_Face face, FT_Matrix* matrix, FT_Vector* delta ); - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_Render_Mode */ - /* */ - /* <Description> */ - /* Render modes supported by FreeType~2. Each mode corresponds to a */ - /* specific type of scanline conversion performed on the outline. */ - /* */ - /* For bitmap fonts and embedded bitmaps the `bitmap->pixel_mode' */ - /* field in the @FT_GlyphSlotRec structure gives the format of the */ - /* returned bitmap. */ - /* */ - /* All modes except @FT_RENDER_MODE_MONO use 256 levels of opacity, */ - /* indicating pixel coverage. Use linear alpha blending and gamma */ - /* correction to correctly render non-monochrome glyph bitmaps onto a */ - /* surface; see @FT_Render_Glyph. */ - /* */ - /* <Values> */ - /* FT_RENDER_MODE_NORMAL :: */ - /* Default render mode; it corresponds to 8-bit anti-aliased */ - /* bitmaps. */ - /* */ - /* FT_RENDER_MODE_LIGHT :: */ - /* This is equivalent to @FT_RENDER_MODE_NORMAL. It is only */ - /* defined as a separate value because render modes are also used */ - /* indirectly to define hinting algorithm selectors. See */ - /* @FT_LOAD_TARGET_XXX for details. */ - /* */ - /* FT_RENDER_MODE_MONO :: */ - /* This mode corresponds to 1-bit bitmaps (with 2~levels of */ - /* opacity). */ - /* */ - /* FT_RENDER_MODE_LCD :: */ - /* This mode corresponds to horizontal RGB and BGR subpixel */ - /* displays like LCD screens. It produces 8-bit bitmaps that are */ - /* 3~times the width of the original glyph outline in pixels, and */ - /* which use the @FT_PIXEL_MODE_LCD mode. */ - /* */ - /* FT_RENDER_MODE_LCD_V :: */ - /* This mode corresponds to vertical RGB and BGR subpixel displays */ - /* (like PDA screens, rotated LCD displays, etc.). It produces */ - /* 8-bit bitmaps that are 3~times the height of the original */ - /* glyph outline in pixels and use the @FT_PIXEL_MODE_LCD_V mode. */ - /* */ - /* <Note> */ - /* Should you define FT_CONFIG_OPTION_SUBPIXEL_RENDERING in your */ - /* `ftoption.h', which enables patented ClearType-style rendering, */ - /* the LCD-optimized glyph bitmaps should be filtered to reduce color */ - /* fringes inherent to this technology. You can either set up LCD */ - /* filtering with @FT_Library_SetLcdFilter or @FT_Face_Properties, */ - /* or do the filtering yourself. The default FreeType LCD rendering */ - /* technology does not require filtering. */ - /* */ - /* The selected render mode only affects vector glyphs of a font. */ - /* Embedded bitmaps often have a different pixel mode like */ - /* @FT_PIXEL_MODE_MONO. You can use @FT_Bitmap_Convert to transform */ - /* them into 8-bit pixmaps. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_Render_Mode + * + * @description: + * Render modes supported by FreeType~2. Each mode corresponds to a + * specific type of scanline conversion performed on the outline. + * + * For bitmap fonts and embedded bitmaps the `bitmap->pixel_mode` field + * in the @FT_GlyphSlotRec structure gives the format of the returned + * bitmap. + * + * All modes except @FT_RENDER_MODE_MONO use 256 levels of opacity, + * indicating pixel coverage. Use linear alpha blending and gamma + * correction to correctly render non-monochrome glyph bitmaps onto a + * surface; see @FT_Render_Glyph. + * + * @values: + * FT_RENDER_MODE_NORMAL :: + * Default render mode; it corresponds to 8-bit anti-aliased bitmaps. + * + * FT_RENDER_MODE_LIGHT :: + * This is equivalent to @FT_RENDER_MODE_NORMAL. It is only defined as + * a separate value because render modes are also used indirectly to + * define hinting algorithm selectors. See @FT_LOAD_TARGET_XXX for + * details. + * + * FT_RENDER_MODE_MONO :: + * This mode corresponds to 1-bit bitmaps (with 2~levels of opacity). + * + * FT_RENDER_MODE_LCD :: + * This mode corresponds to horizontal RGB and BGR subpixel displays + * like LCD screens. It produces 8-bit bitmaps that are 3~times the + * width of the original glyph outline in pixels, and which use the + * @FT_PIXEL_MODE_LCD mode. + * + * FT_RENDER_MODE_LCD_V :: + * This mode corresponds to vertical RGB and BGR subpixel displays + * (like PDA screens, rotated LCD displays, etc.). It produces 8-bit + * bitmaps that are 3~times the height of the original glyph outline in + * pixels and use the @FT_PIXEL_MODE_LCD_V mode. + * + * @note: + * Should you define `FT_CONFIG_OPTION_SUBPIXEL_RENDERING` in your + * `ftoption.h`, which enables patented ClearType-style rendering, the + * LCD-optimized glyph bitmaps should be filtered to reduce color fringes + * inherent to this technology. You can either set up LCD filtering with + * @FT_Library_SetLcdFilter or @FT_Face_Properties, or do the filtering + * yourself. The default FreeType LCD rendering technology does not + * require filtering. + * + * The selected render mode only affects vector glyphs of a font. + * Embedded bitmaps often have a different pixel mode like + * @FT_PIXEL_MODE_MONO. You can use @FT_Bitmap_Convert to transform them + * into 8-bit pixmaps. + */ typedef enum FT_Render_Mode_ { FT_RENDER_MODE_NORMAL = 0, @@ -3248,147 +3265,149 @@ FT_BEGIN_HEADER /* these constants are deprecated; use the corresponding */ - /* `FT_Render_Mode' values instead */ + /* `FT_Render_Mode` values instead */ #define ft_render_mode_normal FT_RENDER_MODE_NORMAL #define ft_render_mode_mono FT_RENDER_MODE_MONO - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Render_Glyph */ - /* */ - /* <Description> */ - /* Convert a given glyph image to a bitmap. It does so by inspecting */ - /* the glyph image format, finding the relevant renderer, and */ - /* invoking it. */ - /* */ - /* <InOut> */ - /* slot :: A handle to the glyph slot containing the image to */ - /* convert. */ - /* */ - /* <Input> */ - /* render_mode :: The render mode used to render the glyph image into */ - /* a bitmap. See @FT_Render_Mode for a list of */ - /* possible values. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* To get meaningful results, font scaling values must be set with */ - /* functions like @FT_Set_Char_Size before calling `FT_Render_Glyph'. */ - /* */ - /* When FreeType outputs a bitmap of a glyph, it really outputs an */ - /* alpha coverage map. If a pixel is completely covered by a */ - /* filled-in outline, the bitmap contains 0xFF at that pixel, meaning */ - /* that 0xFF/0xFF fraction of that pixel is covered, meaning the */ - /* pixel is 100% black (or 0% bright). If a pixel is only 50% */ - /* covered (value 0x80), the pixel is made 50% black (50% bright or a */ - /* middle shade of grey). 0% covered means 0% black (100% bright or */ - /* white). */ - /* */ - /* On high-DPI screens like on smartphones and tablets, the pixels */ - /* are so small that their chance of being completely covered and */ - /* therefore completely black are fairly good. On the low-DPI */ - /* screens, however, the situation is different. The pixels are too */ - /* large for most of the details of a glyph and shades of gray are */ - /* the norm rather than the exception. */ - /* */ - /* This is relevant because all our screens have a second problem: */ - /* they are not linear. 1~+~1 is not~2. Twice the value does not */ - /* result in twice the brightness. When a pixel is only 50% covered, */ - /* the coverage map says 50% black, and this translates to a pixel */ - /* value of 128 when you use 8~bits per channel (0-255). However, */ - /* this does not translate to 50% brightness for that pixel on our */ - /* sRGB and gamma~2.2 screens. Due to their non-linearity, they */ - /* dwell longer in the darks and only a pixel value of about 186 */ - /* results in 50% brightness -- 128 ends up too dark on both bright */ - /* and dark backgrounds. The net result is that dark text looks */ - /* burnt-out, pixely and blotchy on bright background, bright text */ - /* too frail on dark backgrounds, and colored text on colored */ - /* background (for example, red on green) seems to have dark halos or */ - /* `dirt' around it. The situation is especially ugly for diagonal */ - /* stems like in `w' glyph shapes where the quality of FreeType's */ - /* anti-aliasing depends on the correct display of grays. On */ - /* high-DPI screens where smaller, fully black pixels reign supreme, */ - /* this doesn't matter, but on our low-DPI screens with all the gray */ - /* shades, it does. 0% and 100% brightness are the same things in */ - /* linear and non-linear space, just all the shades in-between */ - /* aren't. */ - /* */ - /* The blending function for placing text over a background is */ - /* */ - /* { */ - /* dst = alpha * src + (1 - alpha) * dst , */ - /* } */ - /* */ - /* which is known as the OVER operator. */ - /* */ - /* To correctly composite an antialiased pixel of a glyph onto a */ - /* surface, */ - /* */ - /* 1. take the foreground and background colors (e.g., in sRGB space) */ - /* and apply gamma to get them in a linear space, */ - /* */ - /* 2. use OVER to blend the two linear colors using the glyph pixel */ - /* as the alpha value (remember, the glyph bitmap is an alpha */ - /* coverage bitmap), and */ - /* */ - /* 3. apply inverse gamma to the blended pixel and write it back to */ - /* the image. */ - /* */ - /* Internal testing at Adobe found that a target inverse gamma of~1.8 */ - /* for step~3 gives good results across a wide range of displays with */ - /* an sRGB gamma curve or a similar one. */ - /* */ - /* This process can cost performance. There is an approximation that */ - /* does not need to know about the background color; see */ - /* https://bel.fi/alankila/lcd/ and */ - /* https://bel.fi/alankila/lcd/alpcor.html for details. */ - /* */ - /* *ATTENTION*: Linear blending is even more important when dealing */ - /* with subpixel-rendered glyphs to prevent color-fringing! A */ - /* subpixel-rendered glyph must first be filtered with a filter that */ - /* gives equal weight to the three color primaries and does not */ - /* exceed a sum of 0x100, see section @lcd_filtering. Then the */ - /* only difference to gray linear blending is that subpixel-rendered */ - /* linear blending is done 3~times per pixel: red foreground subpixel */ - /* to red background subpixel and so on for green and blue. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Render_Glyph + * + * @description: + * Convert a given glyph image to a bitmap. It does so by inspecting the + * glyph image format, finding the relevant renderer, and invoking it. + * + * @inout: + * slot :: + * A handle to the glyph slot containing the image to convert. + * + * @input: + * render_mode :: + * The render mode used to render the glyph image into a bitmap. See + * @FT_Render_Mode for a list of possible values. + * + * If @FT_RENDER_MODE_NORMAL is used, a previous call of @FT_Load_Glyph + * with flag @FT_LOAD_COLOR makes FT_Render_Glyph provide a default + * blending of colored glyph layers associated with the current glyph + * slot (provided the font contains such layers) instead of rendering + * the glyph slot's outline. This is an experimental feature; see + * @FT_LOAD_COLOR for more information. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * To get meaningful results, font scaling values must be set with + * functions like @FT_Set_Char_Size before calling `FT_Render_Glyph`. + * + * When FreeType outputs a bitmap of a glyph, it really outputs an alpha + * coverage map. If a pixel is completely covered by a filled-in + * outline, the bitmap contains 0xFF at that pixel, meaning that + * 0xFF/0xFF fraction of that pixel is covered, meaning the pixel is 100% + * black (or 0% bright). If a pixel is only 50% covered (value 0x80), + * the pixel is made 50% black (50% bright or a middle shade of grey). + * 0% covered means 0% black (100% bright or white). + * + * On high-DPI screens like on smartphones and tablets, the pixels are so + * small that their chance of being completely covered and therefore + * completely black are fairly good. On the low-DPI screens, however, + * the situation is different. The pixels are too large for most of the + * details of a glyph and shades of gray are the norm rather than the + * exception. + * + * This is relevant because all our screens have a second problem: they + * are not linear. 1~+~1 is not~2. Twice the value does not result in + * twice the brightness. When a pixel is only 50% covered, the coverage + * map says 50% black, and this translates to a pixel value of 128 when + * you use 8~bits per channel (0-255). However, this does not translate + * to 50% brightness for that pixel on our sRGB and gamma~2.2 screens. + * Due to their non-linearity, they dwell longer in the darks and only a + * pixel value of about 186 results in 50% brightness -- 128 ends up too + * dark on both bright and dark backgrounds. The net result is that dark + * text looks burnt-out, pixely and blotchy on bright background, bright + * text too frail on dark backgrounds, and colored text on colored + * background (for example, red on green) seems to have dark halos or + * 'dirt' around it. The situation is especially ugly for diagonal stems + * like in 'w' glyph shapes where the quality of FreeType's anti-aliasing + * depends on the correct display of grays. On high-DPI screens where + * smaller, fully black pixels reign supreme, this doesn't matter, but on + * our low-DPI screens with all the gray shades, it does. 0% and 100% + * brightness are the same things in linear and non-linear space, just + * all the shades in-between aren't. + * + * The blending function for placing text over a background is + * + * ``` + * dst = alpha * src + (1 - alpha) * dst , + * ``` + * + * which is known as the OVER operator. + * + * To correctly composite an antialiased pixel of a glyph onto a surface, + * + * 1. take the foreground and background colors (e.g., in sRGB space) + * and apply gamma to get them in a linear space, + * + * 2. use OVER to blend the two linear colors using the glyph pixel + * as the alpha value (remember, the glyph bitmap is an alpha coverage + * bitmap), and + * + * 3. apply inverse gamma to the blended pixel and write it back to + * the image. + * + * Internal testing at Adobe found that a target inverse gamma of~1.8 for + * step~3 gives good results across a wide range of displays with an sRGB + * gamma curve or a similar one. + * + * This process can cost performance. There is an approximation that + * does not need to know about the background color; see + * https://bel.fi/alankila/lcd/ and + * https://bel.fi/alankila/lcd/alpcor.html for details. + * + * **ATTENTION**: Linear blending is even more important when dealing + * with subpixel-rendered glyphs to prevent color-fringing! A + * subpixel-rendered glyph must first be filtered with a filter that + * gives equal weight to the three color primaries and does not exceed a + * sum of 0x100, see section @lcd_rendering. Then the only difference to + * gray linear blending is that subpixel-rendered linear blending is done + * 3~times per pixel: red foreground subpixel to red background subpixel + * and so on for green and blue. + */ FT_EXPORT( FT_Error ) FT_Render_Glyph( FT_GlyphSlot slot, FT_Render_Mode render_mode ); - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_Kerning_Mode */ - /* */ - /* <Description> */ - /* An enumeration to specify the format of kerning values returned by */ - /* @FT_Get_Kerning. */ - /* */ - /* <Values> */ - /* FT_KERNING_DEFAULT :: Return grid-fitted kerning distances in */ - /* 26.6 fractional pixels. */ - /* */ - /* FT_KERNING_UNFITTED :: Return un-grid-fitted kerning distances in */ - /* 26.6 fractional pixels. */ - /* */ - /* FT_KERNING_UNSCALED :: Return the kerning vector in original font */ - /* units. */ - /* */ - /* <Note> */ - /* FT_KERNING_DEFAULT returns full pixel values; it also makes */ - /* FreeType heuristically scale down kerning distances at small ppem */ - /* values so that they don't become too big. */ - /* */ - /* Both FT_KERNING_DEFAULT and FT_KERNING_UNFITTED use the current */ - /* horizontal scaling factor (as set e.g. with @FT_Set_Char_Size) to */ - /* convert font units to pixels. */ - /* */ + /************************************************************************** + * + * @enum: + * FT_Kerning_Mode + * + * @description: + * An enumeration to specify the format of kerning values returned by + * @FT_Get_Kerning. + * + * @values: + * FT_KERNING_DEFAULT :: + * Return grid-fitted kerning distances in 26.6 fractional pixels. + * + * FT_KERNING_UNFITTED :: + * Return un-grid-fitted kerning distances in 26.6 fractional pixels. + * + * FT_KERNING_UNSCALED :: + * Return the kerning vector in original font units. + * + * @note: + * `FT_KERNING_DEFAULT` returns full pixel values; it also makes FreeType + * heuristically scale down kerning distances at small ppem values so + * that they don't become too big. + * + * Both `FT_KERNING_DEFAULT` and `FT_KERNING_UNFITTED` use the current + * horizontal scaling factor (as set e.g. with @FT_Set_Char_Size) to + * convert font units to pixels. + */ typedef enum FT_Kerning_Mode_ { FT_KERNING_DEFAULT = 0, @@ -3399,50 +3418,53 @@ FT_BEGIN_HEADER /* these constants are deprecated; use the corresponding */ - /* `FT_Kerning_Mode' values instead */ + /* `FT_Kerning_Mode` values instead */ #define ft_kerning_default FT_KERNING_DEFAULT #define ft_kerning_unfitted FT_KERNING_UNFITTED #define ft_kerning_unscaled FT_KERNING_UNSCALED - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Kerning */ - /* */ - /* <Description> */ - /* Return the kerning vector between two glyphs of the same face. */ - /* */ - /* <Input> */ - /* face :: A handle to a source face object. */ - /* */ - /* left_glyph :: The index of the left glyph in the kern pair. */ - /* */ - /* right_glyph :: The index of the right glyph in the kern pair. */ - /* */ - /* kern_mode :: See @FT_Kerning_Mode for more information. */ - /* Determines the scale and dimension of the returned */ - /* kerning vector. */ - /* */ - /* <Output> */ - /* akerning :: The kerning vector. This is either in font units, */ - /* fractional pixels (26.6 format), or pixels for */ - /* scalable formats, and in pixels for fixed-sizes */ - /* formats. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* Only horizontal layouts (left-to-right & right-to-left) are */ - /* supported by this method. Other layouts, or more sophisticated */ - /* kernings, are out of the scope of this API function -- they can be */ - /* implemented through format-specific interfaces. */ - /* */ - /* Kerning for OpenType fonts implemented in a `GPOS' table is not */ - /* supported; use @FT_HAS_KERNING to find out whether a font has data */ - /* that can be extracted with `FT_Get_Kerning'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Kerning + * + * @description: + * Return the kerning vector between two glyphs of the same face. + * + * @input: + * face :: + * A handle to a source face object. + * + * left_glyph :: + * The index of the left glyph in the kern pair. + * + * right_glyph :: + * The index of the right glyph in the kern pair. + * + * kern_mode :: + * See @FT_Kerning_Mode for more information. Determines the scale and + * dimension of the returned kerning vector. + * + * @output: + * akerning :: + * The kerning vector. This is either in font units, fractional pixels + * (26.6 format), or pixels for scalable formats, and in pixels for + * fixed-sizes formats. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * Only horizontal layouts (left-to-right & right-to-left) are supported + * by this method. Other layouts, or more sophisticated kernings, are + * out of the scope of this API function -- they can be implemented + * through format-specific interfaces. + * + * Kerning for OpenType fonts implemented in a 'GPOS' table is not + * supported; use @FT_HAS_KERNING to find out whether a font has data + * that can be extracted with `FT_Get_Kerning`. + */ FT_EXPORT( FT_Error ) FT_Get_Kerning( FT_Face face, FT_UInt left_glyph, @@ -3451,39 +3473,42 @@ FT_BEGIN_HEADER FT_Vector *akerning ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Track_Kerning */ - /* */ - /* <Description> */ - /* Return the track kerning for a given face object at a given size. */ - /* */ - /* <Input> */ - /* face :: A handle to a source face object. */ - /* */ - /* point_size :: The point size in 16.16 fractional points. */ - /* */ - /* degree :: The degree of tightness. Increasingly negative */ - /* values represent tighter track kerning, while */ - /* increasingly positive values represent looser track */ - /* kerning. Value zero means no track kerning. */ - /* */ - /* <Output> */ - /* akerning :: The kerning in 16.16 fractional points, to be */ - /* uniformly applied between all glyphs. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* Currently, only the Type~1 font driver supports track kerning, */ - /* using data from AFM files (if attached with @FT_Attach_File or */ - /* @FT_Attach_Stream). */ - /* */ - /* Only very few AFM files come with track kerning data; please refer */ - /* to Adobe's AFM specification for more details. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Track_Kerning + * + * @description: + * Return the track kerning for a given face object at a given size. + * + * @input: + * face :: + * A handle to a source face object. + * + * point_size :: + * The point size in 16.16 fractional points. + * + * degree :: + * The degree of tightness. Increasingly negative values represent + * tighter track kerning, while increasingly positive values represent + * looser track kerning. Value zero means no track kerning. + * + * @output: + * akerning :: + * The kerning in 16.16 fractional points, to be uniformly applied + * between all glyphs. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * Currently, only the Type~1 font driver supports track kerning, using + * data from AFM files (if attached with @FT_Attach_File or + * @FT_Attach_Stream). + * + * Only very few AFM files come with track kerning data; please refer to + * Adobe's AFM specification for more details. + */ FT_EXPORT( FT_Error ) FT_Get_Track_Kerning( FT_Face face, FT_Fixed point_size, @@ -3491,45 +3516,46 @@ FT_BEGIN_HEADER FT_Fixed* akerning ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Glyph_Name */ - /* */ - /* <Description> */ - /* Retrieve the ASCII name of a given glyph in a face. This only */ - /* works for those faces where @FT_HAS_GLYPH_NAMES(face) returns~1. */ - /* */ - /* <Input> */ - /* face :: A handle to a source face object. */ - /* */ - /* glyph_index :: The glyph index. */ - /* */ - /* buffer_max :: The maximum number of bytes available in the */ - /* buffer. */ - /* */ - /* <Output> */ - /* buffer :: A pointer to a target buffer where the name is */ - /* copied to. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* An error is returned if the face doesn't provide glyph names or if */ - /* the glyph index is invalid. In all cases of failure, the first */ - /* byte of `buffer' is set to~0 to indicate an empty name. */ - /* */ - /* The glyph name is truncated to fit within the buffer if it is too */ - /* long. The returned string is always zero-terminated. */ - /* */ - /* Be aware that FreeType reorders glyph indices internally so that */ - /* glyph index~0 always corresponds to the `missing glyph' (called */ - /* `.notdef'). */ - /* */ - /* This function always returns an error if the config macro */ - /* `FT_CONFIG_OPTION_NO_GLYPH_NAMES' is not defined in `ftoption.h'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Glyph_Name + * + * @description: + * Retrieve the ASCII name of a given glyph in a face. This only works + * for those faces where @FT_HAS_GLYPH_NAMES(face) returns~1. + * + * @input: + * face :: + * A handle to a source face object. + * + * glyph_index :: + * The glyph index. + * + * buffer_max :: + * The maximum number of bytes available in the buffer. + * + * @output: + * buffer :: + * A pointer to a target buffer where the name is copied to. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * An error is returned if the face doesn't provide glyph names or if the + * glyph index is invalid. In all cases of failure, the first byte of + * `buffer` is set to~0 to indicate an empty name. + * + * The glyph name is truncated to fit within the buffer if it is too + * long. The returned string is always zero-terminated. + * + * Be aware that FreeType reorders glyph indices internally so that glyph + * index~0 always corresponds to the 'missing glyph' (called '.notdef'). + * + * This function always returns an error if the config macro + * `FT_CONFIG_OPTION_NO_GLYPH_NAMES` is not defined in `ftoption.h`. + */ FT_EXPORT( FT_Error ) FT_Get_Glyph_Name( FT_Face face, FT_UInt glyph_index, @@ -3537,107 +3563,109 @@ FT_BEGIN_HEADER FT_UInt buffer_max ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Postscript_Name */ - /* */ - /* <Description> */ - /* Retrieve the ASCII PostScript name of a given face, if available. */ - /* This only works with PostScript, TrueType, and OpenType fonts. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Return> */ - /* A pointer to the face's PostScript name. NULL if unavailable. */ - /* */ - /* <Note> */ - /* The returned pointer is owned by the face and is destroyed with */ - /* it. */ - /* */ - /* For variation fonts, this string changes if you select a different */ - /* instance, and you have to call `FT_Get_PostScript_Name' again to */ - /* retrieve it. FreeType follows Adobe TechNote #5902, `Generating */ - /* PostScript Names for Fonts Using OpenType Font Variations'. */ - /* */ - /* https://download.macromedia.com/pub/developer/opentype/tech-notes/5902.AdobePSNameGeneration.html */ - /* */ - /* [Since 2.9] Special PostScript names for named instances are only */ - /* returned if the named instance is set with @FT_Set_Named_Instance */ - /* (and the font has corresponding entries in its `fvar' table). If */ - /* @FT_IS_VARIATION returns true, the algorithmically derived */ - /* PostScript name is provided, not looking up special entries for */ - /* named instances. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Postscript_Name + * + * @description: + * Retrieve the ASCII PostScript name of a given face, if available. + * This only works with PostScript, TrueType, and OpenType fonts. + * + * @input: + * face :: + * A handle to the source face object. + * + * @return: + * A pointer to the face's PostScript name. `NULL` if unavailable. + * + * @note: + * The returned pointer is owned by the face and is destroyed with it. + * + * For variation fonts, this string changes if you select a different + * instance, and you have to call `FT_Get_PostScript_Name` again to + * retrieve it. FreeType follows Adobe TechNote #5902, 'Generating + * PostScript Names for Fonts Using OpenType Font Variations'. + * + * https://download.macromedia.com/pub/developer/opentype/tech-notes/5902.AdobePSNameGeneration.html + * + * [Since 2.9] Special PostScript names for named instances are only + * returned if the named instance is set with @FT_Set_Named_Instance (and + * the font has corresponding entries in its 'fvar' table). If + * @FT_IS_VARIATION returns true, the algorithmically derived PostScript + * name is provided, not looking up special entries for named instances. + */ FT_EXPORT( const char* ) FT_Get_Postscript_Name( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Select_Charmap */ - /* */ - /* <Description> */ - /* Select a given charmap by its encoding tag (as listed in */ - /* `freetype.h'). */ - /* */ - /* <InOut> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Input> */ - /* encoding :: A handle to the selected encoding. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* This function returns an error if no charmap in the face */ - /* corresponds to the encoding queried here. */ - /* */ - /* Because many fonts contain more than a single cmap for Unicode */ - /* encoding, this function has some special code to select the one */ - /* that covers Unicode best (`best' in the sense that a UCS-4 cmap is */ - /* preferred to a UCS-2 cmap). It is thus preferable to */ - /* @FT_Set_Charmap in this case. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Select_Charmap + * + * @description: + * Select a given charmap by its encoding tag (as listed in + * `freetype.h`). + * + * @inout: + * face :: + * A handle to the source face object. + * + * @input: + * encoding :: + * A handle to the selected encoding. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * This function returns an error if no charmap in the face corresponds + * to the encoding queried here. + * + * Because many fonts contain more than a single cmap for Unicode + * encoding, this function has some special code to select the one that + * covers Unicode best ('best' in the sense that a UCS-4 cmap is + * preferred to a UCS-2 cmap). It is thus preferable to @FT_Set_Charmap + * in this case. + */ FT_EXPORT( FT_Error ) FT_Select_Charmap( FT_Face face, FT_Encoding encoding ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Set_Charmap */ - /* */ - /* <Description> */ - /* Select a given charmap for character code to glyph index mapping. */ - /* */ - /* <InOut> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Input> */ - /* charmap :: A handle to the selected charmap. */ - /* */ - /* <Return> */ - /* FreeType error code. 0~means success. */ - /* */ - /* <Note> */ - /* This function returns an error if the charmap is not part of */ - /* the face (i.e., if it is not listed in the `face->charmaps' */ - /* table). */ - /* */ - /* It also fails if an OpenType type~14 charmap is selected (which */ - /* doesn't map character codes to glyph indices at all). */ - /* */ + /************************************************************************** + * + * @function: + * FT_Set_Charmap + * + * @description: + * Select a given charmap for character code to glyph index mapping. + * + * @inout: + * face :: + * A handle to the source face object. + * + * @input: + * charmap :: + * A handle to the selected charmap. + * + * @return: + * FreeType error code. 0~means success. + * + * @note: + * This function returns an error if the charmap is not part of the face + * (i.e., if it is not listed in the `face->charmaps` table). + * + * It also fails if an OpenType type~14 charmap is selected (which + * doesn't map character codes to glyph indices at all). + */ FT_EXPORT( FT_Error ) FT_Set_Charmap( FT_Face face, FT_CharMap charmap ); - /************************************************************************* + /************************************************************************** * * @function: * FT_Get_Charmap_Index @@ -3651,139 +3679,143 @@ FT_BEGIN_HEADER * * @return: * The index into the array of character maps within the face to which - * `charmap' belongs. If an error occurs, -1 is returned. + * `charmap` belongs. If an error occurs, -1 is returned. * */ FT_EXPORT( FT_Int ) FT_Get_Charmap_Index( FT_CharMap charmap ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Char_Index */ - /* */ - /* <Description> */ - /* Return the glyph index of a given character code. This function */ - /* uses the currently selected charmap to do the mapping. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* charcode :: The character code. */ - /* */ - /* <Return> */ - /* The glyph index. 0~means `undefined character code'. */ - /* */ - /* <Note> */ - /* If you use FreeType to manipulate the contents of font files */ - /* directly, be aware that the glyph index returned by this function */ - /* doesn't always correspond to the internal indices used within the */ - /* file. This is done to ensure that value~0 always corresponds to */ - /* the `missing glyph'. If the first glyph is not named `.notdef', */ - /* then for Type~1 and Type~42 fonts, `.notdef' will be moved into */ - /* the glyph ID~0 position, and whatever was there will be moved to */ - /* the position `.notdef' had. For Type~1 fonts, if there is no */ - /* `.notdef' glyph at all, then one will be created at index~0 and */ - /* whatever was there will be moved to the last index -- Type~42 */ - /* fonts are considered invalid under this condition. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Char_Index + * + * @description: + * Return the glyph index of a given character code. This function uses + * the currently selected charmap to do the mapping. + * + * @input: + * face :: + * A handle to the source face object. + * + * charcode :: + * The character code. + * + * @return: + * The glyph index. 0~means 'undefined character code'. + * + * @note: + * If you use FreeType to manipulate the contents of font files directly, + * be aware that the glyph index returned by this function doesn't always + * correspond to the internal indices used within the file. This is done + * to ensure that value~0 always corresponds to the 'missing glyph'. If + * the first glyph is not named '.notdef', then for Type~1 and Type~42 + * fonts, '.notdef' will be moved into the glyph ID~0 position, and + * whatever was there will be moved to the position '.notdef' had. For + * Type~1 fonts, if there is no '.notdef' glyph at all, then one will be + * created at index~0 and whatever was there will be moved to the last + * index -- Type~42 fonts are considered invalid under this condition. + */ FT_EXPORT( FT_UInt ) FT_Get_Char_Index( FT_Face face, FT_ULong charcode ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_First_Char */ - /* */ - /* <Description> */ - /* Return the first character code in the current charmap of a given */ - /* face, together with its corresponding glyph index. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Output> */ - /* agindex :: Glyph index of first character code. 0~if charmap is */ - /* empty. */ - /* */ - /* <Return> */ - /* The charmap's first character code. */ - /* */ - /* <Note> */ - /* You should use this function together with @FT_Get_Next_Char to */ - /* parse all character codes available in a given charmap. The code */ - /* should look like this: */ - /* */ - /* { */ - /* FT_ULong charcode; */ - /* FT_UInt gindex; */ - /* */ - /* */ - /* charcode = FT_Get_First_Char( face, &gindex ); */ - /* while ( gindex != 0 ) */ - /* { */ - /* ... do something with (charcode,gindex) pair ... */ - /* */ - /* charcode = FT_Get_Next_Char( face, charcode, &gindex ); */ - /* } */ - /* } */ - /* */ - /* Be aware that character codes can have values up to 0xFFFFFFFF; */ - /* this might happen for non-Unicode or malformed cmaps. However, */ - /* even with regular Unicode encoding, so-called `last resort fonts' */ - /* (using SFNT cmap format 13, see function @FT_Get_CMap_Format) */ - /* normally have entries for all Unicode characters up to 0x1FFFFF, */ - /* which can cause *a lot* of iterations. */ - /* */ - /* Note that `*agindex' is set to~0 if the charmap is empty. The */ - /* result itself can be~0 in two cases: if the charmap is empty or */ - /* if the value~0 is the first valid character code. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_First_Char + * + * @description: + * Return the first character code in the current charmap of a given + * face, together with its corresponding glyph index. + * + * @input: + * face :: + * A handle to the source face object. + * + * @output: + * agindex :: + * Glyph index of first character code. 0~if charmap is empty. + * + * @return: + * The charmap's first character code. + * + * @note: + * You should use this function together with @FT_Get_Next_Char to parse + * all character codes available in a given charmap. The code should + * look like this: + * + * ``` + * FT_ULong charcode; + * FT_UInt gindex; + * + * + * charcode = FT_Get_First_Char( face, &gindex ); + * while ( gindex != 0 ) + * { + * ... do something with (charcode,gindex) pair ... + * + * charcode = FT_Get_Next_Char( face, charcode, &gindex ); + * } + * ``` + * + * Be aware that character codes can have values up to 0xFFFFFFFF; this + * might happen for non-Unicode or malformed cmaps. However, even with + * regular Unicode encoding, so-called 'last resort fonts' (using SFNT + * cmap format 13, see function @FT_Get_CMap_Format) normally have + * entries for all Unicode characters up to 0x1FFFFF, which can cause *a + * lot* of iterations. + * + * Note that `*agindex` is set to~0 if the charmap is empty. The result + * itself can be~0 in two cases: if the charmap is empty or if the + * value~0 is the first valid character code. + */ FT_EXPORT( FT_ULong ) FT_Get_First_Char( FT_Face face, FT_UInt *agindex ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Next_Char */ - /* */ - /* <Description> */ - /* Return the next character code in the current charmap of a given */ - /* face following the value `char_code', as well as the corresponding */ - /* glyph index. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* char_code :: The starting character code. */ - /* */ - /* <Output> */ - /* agindex :: Glyph index of next character code. 0~if charmap */ - /* is empty. */ - /* */ - /* <Return> */ - /* The charmap's next character code. */ - /* */ - /* <Note> */ - /* You should use this function with @FT_Get_First_Char to walk */ - /* over all character codes available in a given charmap. See the */ - /* note for that function for a simple code example. */ - /* */ - /* Note that `*agindex' is set to~0 when there are no more codes in */ - /* the charmap. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Next_Char + * + * @description: + * Return the next character code in the current charmap of a given face + * following the value `char_code`, as well as the corresponding glyph + * index. + * + * @input: + * face :: + * A handle to the source face object. + * + * char_code :: + * The starting character code. + * + * @output: + * agindex :: + * Glyph index of next character code. 0~if charmap is empty. + * + * @return: + * The charmap's next character code. + * + * @note: + * You should use this function with @FT_Get_First_Char to walk over all + * character codes available in a given charmap. See the note for that + * function for a simple code example. + * + * Note that `*agindex` is set to~0 when there are no more codes in the + * charmap. + */ FT_EXPORT( FT_ULong ) FT_Get_Next_Char( FT_Face face, FT_ULong char_code, FT_UInt *agindex ); - /************************************************************************* + /************************************************************************** * * @function: * FT_Face_Properties @@ -3791,27 +3823,26 @@ FT_BEGIN_HEADER * @description: * Set or override certain (library or module-wide) properties on a * face-by-face basis. Useful for finer-grained control and avoiding - * locks on shared structures (threads can modify their own faces as - * they see fit). + * locks on shared structures (threads can modify their own faces as they + * see fit). * - * Contrary to @FT_Property_Set, this function uses @FT_Parameter so - * that you can pass multiple properties to the target face in one call. - * Note that only a subset of the available properties can be - * controlled. + * Contrary to @FT_Property_Set, this function uses @FT_Parameter so that + * you can pass multiple properties to the target face in one call. Note + * that only a subset of the available properties can be controlled. * * * @FT_PARAM_TAG_STEM_DARKENING (stem darkening, corresponding to the - * property `no-stem-darkening' provided by the `autofit', `cff', - * `type1', and `t1cid' modules; see @no-stem-darkening). + * property `no-stem-darkening` provided by the 'autofit', 'cff', + * 'type1', and 't1cid' modules; see @no-stem-darkening). * * * @FT_PARAM_TAG_LCD_FILTER_WEIGHTS (LCD filter weights, corresponding * to function @FT_Library_SetLcdFilterWeights). * * * @FT_PARAM_TAG_RANDOM_SEED (seed value for the CFF, Type~1, and CID - * `random' operator, corresponding to the `random-seed' property - * provided by the `cff', `type1', and `t1cid' modules; see + * 'random' operator, corresponding to the `random-seed` property + * provided by the 'cff', 'type1', and 't1cid' modules; see * @random-seed). * - * Pass NULL as `data' in @FT_Parameter for a given tag to reset the + * Pass `NULL` as `data` in @FT_Parameter for a given tag to reset the * option and use the library or module default again. * * @input: @@ -3822,17 +3853,17 @@ FT_BEGIN_HEADER * The number of properties that follow. * * properties :: - * A handle to an @FT_Parameter array with `num_properties' elements. + * A handle to an @FT_Parameter array with `num_properties` elements. * * @return: * FreeType error code. 0~means success. * - * @note: - * Here an example that sets three properties. You must define - * FT_CONFIG_OPTION_SUBPIXEL_RENDERING to make the LCD filter examples + * @example: + * Here is an example that sets three properties. You must define + * `FT_CONFIG_OPTION_SUBPIXEL_RENDERING` to make the LCD filter examples * work. * - * { + * ``` * FT_Parameter property1; * FT_Bool darken_stems = 1; * @@ -3858,11 +3889,11 @@ FT_BEGIN_HEADER * property3.data = &random_seed; * * FT_Face_Properties( face, 3, properties ); - * } + * ``` * * The next example resets a single property to its default value. * - * { + * ``` * FT_Parameter property; * * @@ -3870,7 +3901,7 @@ FT_BEGIN_HEADER * property.data = NULL; * * FT_Face_Properties( face, 1, &property ); - * } + * ``` * * @since: * 2.8 @@ -3882,37 +3913,40 @@ FT_BEGIN_HEADER FT_Parameter* properties ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_Name_Index */ - /* */ - /* <Description> */ - /* Return the glyph index of a given glyph name. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* glyph_name :: The glyph name. */ - /* */ - /* <Return> */ - /* The glyph index. 0~means `undefined character code'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_Name_Index + * + * @description: + * Return the glyph index of a given glyph name. + * + * @input: + * face :: + * A handle to the source face object. + * + * glyph_name :: + * The glyph name. + * + * @return: + * The glyph index. 0~means 'undefined character code'. + */ FT_EXPORT( FT_UInt ) FT_Get_Name_Index( FT_Face face, FT_String* glyph_name ); - /************************************************************************* + /************************************************************************** * - * @macro: + * @enum: * FT_SUBGLYPH_FLAG_XXX * * @description: - * A list of constants describing subglyphs. Please refer to the - * `glyf' table description in the OpenType specification for the - * meaning of the various flags (which get synthesized for - * non-OpenType subglyphs). + * A list of constants describing subglyphs. Please refer to the 'glyf' + * table description in the OpenType specification for the meaning of the + * various flags (which get synthesized for non-OpenType subglyphs). + * + * https://docs.microsoft.com/en-us/typography/opentype/spec/glyf#composite-glyph-description * * @values: * FT_SUBGLYPH_FLAG_ARGS_ARE_WORDS :: @@ -3933,15 +3967,15 @@ FT_BEGIN_HEADER #define FT_SUBGLYPH_FLAG_USE_MY_METRICS 0x200 - /************************************************************************* + /************************************************************************** * - * @func: + * @function: * FT_Get_SubGlyph_Info * * @description: * Retrieve a description of a given subglyph. Only use it if - * `glyph->format' is @FT_GLYPH_FORMAT_COMPOSITE; an error is - * returned otherwise. + * `glyph->format` is @FT_GLYPH_FORMAT_COMPOSITE; an error is returned + * otherwise. * * @input: * glyph :: @@ -3949,7 +3983,7 @@ FT_BEGIN_HEADER * * sub_index :: * The index of the subglyph. Must be less than - * `glyph->num_subglyphs'. + * `glyph->num_subglyphs`. * * @output: * p_index :: @@ -3971,10 +4005,12 @@ FT_BEGIN_HEADER * FreeType error code. 0~means success. * * @note: - * The values of `*p_arg1', `*p_arg2', and `*p_transform' must be - * interpreted depending on the flags returned in `*p_flags'. See the + * The values of `*p_arg1`, `*p_arg2`, and `*p_transform` must be + * interpreted depending on the flags returned in `*p_flags`. See the * OpenType specification for details. * + * https://docs.microsoft.com/en-us/typography/opentype/spec/glyf#composite-glyph-description + * */ FT_EXPORT( FT_Error ) FT_Get_SubGlyph_Info( FT_GlyphSlot glyph, @@ -3986,59 +4022,228 @@ FT_BEGIN_HEADER FT_Matrix *p_transform ); - /*************************************************************************/ - /* */ - /* <Enum> */ - /* FT_FSTYPE_XXX */ - /* */ - /* <Description> */ - /* A list of bit flags used in the `fsType' field of the OS/2 table */ - /* in a TrueType or OpenType font and the `FSType' entry in a */ - /* PostScript font. These bit flags are returned by */ - /* @FT_Get_FSType_Flags; they inform client applications of embedding */ - /* and subsetting restrictions associated with a font. */ - /* */ - /* See */ - /* https://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/FontPolicies.pdf */ - /* for more details. */ - /* */ - /* <Values> */ - /* FT_FSTYPE_INSTALLABLE_EMBEDDING :: */ - /* Fonts with no fsType bit set may be embedded and permanently */ - /* installed on the remote system by an application. */ - /* */ - /* FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING :: */ - /* Fonts that have only this bit set must not be modified, embedded */ - /* or exchanged in any manner without first obtaining permission of */ - /* the font software copyright owner. */ - /* */ - /* FT_FSTYPE_PREVIEW_AND_PRINT_EMBEDDING :: */ - /* The font may be embedded and temporarily loaded on the remote */ - /* system. Documents containing Preview & Print fonts must be */ - /* opened `read-only'; no edits can be applied to the document. */ - /* */ - /* FT_FSTYPE_EDITABLE_EMBEDDING :: */ - /* The font may be embedded but must only be installed temporarily */ - /* on other systems. In contrast to Preview & Print fonts, */ - /* documents containing editable fonts may be opened for reading, */ - /* editing is permitted, and changes may be saved. */ - /* */ - /* FT_FSTYPE_NO_SUBSETTING :: */ - /* The font may not be subsetted prior to embedding. */ - /* */ - /* FT_FSTYPE_BITMAP_EMBEDDING_ONLY :: */ - /* Only bitmaps contained in the font may be embedded; no outline */ - /* data may be embedded. If there are no bitmaps available in the */ - /* font, then the font is unembeddable. */ - /* */ - /* <Note> */ - /* The flags are ORed together, thus more than a single value can be */ - /* returned. */ - /* */ - /* While the `fsType' flags can indicate that a font may be embedded, */ - /* a license with the font vendor may be separately required to use */ - /* the font in this way. */ - /* */ + /************************************************************************** + * + * @section: + * layer_management + * + * @title: + * Glyph Layer Management + * + * @abstract: + * Retrieving and manipulating OpenType's 'COLR' table data. + * + * @description: + * The functions described here allow access of colored glyph layer data + * in OpenType's 'COLR' tables. + */ + + + /************************************************************************** + * + * @struct: + * FT_LayerIterator + * + * @description: + * This iterator object is needed for @FT_Get_Color_Glyph_Layer. + * + * @fields: + * num_layers :: + * The number of glyph layers for the requested glyph index. Will be + * set by @FT_Get_Color_Glyph_Layer. + * + * layer :: + * The current layer. Will be set by @FT_Get_Color_Glyph_Layer. + * + * p :: + * An opaque pointer into 'COLR' table data. The caller must set this + * to `NULL` before the first call of @FT_Get_Color_Glyph_Layer. + */ + typedef struct FT_LayerIterator_ + { + FT_UInt num_layers; + FT_UInt layer; + FT_Byte* p; + + } FT_LayerIterator; + + + /************************************************************************** + * + * @function: + * FT_Get_Color_Glyph_Layer + * + * @description: + * This is an interface to the 'COLR' table in OpenType fonts to + * iteratively retrieve the colored glyph layers associated with the + * current glyph slot. + * + * https://docs.microsoft.com/en-us/typography/opentype/spec/colr + * + * The glyph layer data for a given glyph index, if present, provides an + * alternative, multi-colour glyph representation: Instead of rendering + * the outline or bitmap with the given glyph index, glyphs with the + * indices and colors returned by this function are rendered layer by + * layer. + * + * The returned elements are ordered in the z~direction from bottom to + * top; the 'n'th element should be rendered with the associated palette + * color and blended on top of the already rendered layers (elements 0, + * 1, ..., n-1). + * + * @input: + * face :: + * A handle to the parent face object. + * + * base_glyph :: + * The glyph index the colored glyph layers are associated with. + * + * @inout: + * iterator :: + * An @FT_LayerIterator object. For the first call you should set + * `iterator->p` to `NULL`. For all following calls, simply use the + * same object again. + * + * @output: + * aglyph_index :: + * The glyph index of the current layer. + * + * acolor_index :: + * The color index into the font face's color palette of the current + * layer. The value 0xFFFF is special; it doesn't reference a palette + * entry but indicates that the text foreground color should be used + * instead (to be set up by the application outside of FreeType). + * + * The color palette can be retrieved with @FT_Palette_Select. + * + * @return: + * Value~1 if everything is OK. If there are no more layers (or if there + * are no layers at all), value~0 gets returned. In case of an error, + * value~0 is returned also. + * + * @note: + * This function is necessary if you want to handle glyph layers by + * yourself. In particular, functions that operate with @FT_GlyphRec + * objects (like @FT_Get_Glyph or @FT_Glyph_To_Bitmap) don't have access + * to this information. + * + * Note that @FT_Render_Glyph is able to handle colored glyph layers + * automatically if the @FT_LOAD_COLOR flag is passed to a previous call + * to @FT_Load_Glyph. [This is an experimental feature.] + * + * @example: + * ``` + * FT_Color* palette; + * FT_LayerIterator iterator; + * + * FT_Bool have_layers; + * FT_UInt layer_glyph_index; + * FT_UInt layer_color_index; + * + * + * error = FT_Palette_Select( face, palette_index, &palette ); + * if ( error ) + * palette = NULL; + * + * iterator.p = NULL; + * have_layers = FT_Get_Color_Glyph_Layer( face, + * glyph_index, + * &layer_glyph_index, + * &layer_color_index, + * &iterator ); + * + * if ( palette && have_layers ) + * { + * do + * { + * FT_Color layer_color; + * + * + * if ( layer_color_index == 0xFFFF ) + * layer_color = text_foreground_color; + * else + * layer_color = palette[layer_color_index]; + * + * // Load and render glyph `layer_glyph_index', then + * // blend resulting pixmap (using color `layer_color') + * // with previously created pixmaps. + * + * } while ( FT_Get_Color_Glyph_Layer( face, + * glyph_index, + * &layer_glyph_index, + * &layer_color_index, + * &iterator ) ); + * } + * ``` + */ + FT_EXPORT( FT_Bool ) + FT_Get_Color_Glyph_Layer( FT_Face face, + FT_UInt base_glyph, + FT_UInt *aglyph_index, + FT_UInt *acolor_index, + FT_LayerIterator* iterator ); + + + /************************************************************************** + * + * @section: + * base_interface + * + */ + + /************************************************************************** + * + * @enum: + * FT_FSTYPE_XXX + * + * @description: + * A list of bit flags used in the `fsType` field of the OS/2 table in a + * TrueType or OpenType font and the `FSType` entry in a PostScript font. + * These bit flags are returned by @FT_Get_FSType_Flags; they inform + * client applications of embedding and subsetting restrictions + * associated with a font. + * + * See + * https://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/FontPolicies.pdf + * for more details. + * + * @values: + * FT_FSTYPE_INSTALLABLE_EMBEDDING :: + * Fonts with no fsType bit set may be embedded and permanently + * installed on the remote system by an application. + * + * FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING :: + * Fonts that have only this bit set must not be modified, embedded or + * exchanged in any manner without first obtaining permission of the + * font software copyright owner. + * + * FT_FSTYPE_PREVIEW_AND_PRINT_EMBEDDING :: + * The font may be embedded and temporarily loaded on the remote + * system. Documents containing Preview & Print fonts must be opened + * 'read-only'; no edits can be applied to the document. + * + * FT_FSTYPE_EDITABLE_EMBEDDING :: + * The font may be embedded but must only be installed temporarily on + * other systems. In contrast to Preview & Print fonts, documents + * containing editable fonts may be opened for reading, editing is + * permitted, and changes may be saved. + * + * FT_FSTYPE_NO_SUBSETTING :: + * The font may not be subsetted prior to embedding. + * + * FT_FSTYPE_BITMAP_EMBEDDING_ONLY :: + * Only bitmaps contained in the font may be embedded; no outline data + * may be embedded. If there are no bitmaps available in the font, + * then the font is unembeddable. + * + * @note: + * The flags are ORed together, thus more than a single value can be + * returned. + * + * While the `fsType` flags can indicate that a font may be embedded, a + * license with the font vendor may be separately required to use the + * font in this way. + */ #define FT_FSTYPE_INSTALLABLE_EMBEDDING 0x0000 #define FT_FSTYPE_RESTRICTED_LICENSE_EMBEDDING 0x0002 #define FT_FSTYPE_PREVIEW_AND_PRINT_EMBEDDING 0x0004 @@ -4047,548 +4252,563 @@ FT_BEGIN_HEADER #define FT_FSTYPE_BITMAP_EMBEDDING_ONLY 0x0200 - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Get_FSType_Flags */ - /* */ - /* <Description> */ - /* Return the `fsType' flags for a font. */ - /* */ - /* <Input> */ - /* face :: A handle to the source face object. */ - /* */ - /* <Return> */ - /* The `fsType' flags, see @FT_FSTYPE_XXX. */ - /* */ - /* <Note> */ - /* Use this function rather than directly reading the `fs_type' field */ - /* in the @PS_FontInfoRec structure, which is only guaranteed to */ - /* return the correct results for Type~1 fonts. */ - /* */ - /* <Since> */ - /* 2.3.8 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Get_FSType_Flags + * + * @description: + * Return the `fsType` flags for a font. + * + * @input: + * face :: + * A handle to the source face object. + * + * @return: + * The `fsType` flags, see @FT_FSTYPE_XXX. + * + * @note: + * Use this function rather than directly reading the `fs_type` field in + * the @PS_FontInfoRec structure, which is only guaranteed to return the + * correct results for Type~1 fonts. + * + * @since: + * 2.3.8 + */ FT_EXPORT( FT_UShort ) FT_Get_FSType_Flags( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Section> */ - /* glyph_variants */ - /* */ - /* <Title> */ - /* Unicode Variation Sequences */ - /* */ - /* <Abstract> */ - /* The FreeType~2 interface to Unicode Variation Sequences (UVS), */ - /* using the SFNT cmap format~14. */ - /* */ - /* <Description> */ - /* Many characters, especially for CJK scripts, have variant forms. */ - /* They are a sort of grey area somewhere between being totally */ - /* irrelevant and semantically distinct; for this reason, the Unicode */ - /* consortium decided to introduce Variation Sequences (VS), */ - /* consisting of a Unicode base character and a variation selector */ - /* instead of further extending the already huge number of */ - /* characters. */ - /* */ - /* Unicode maintains two different sets, namely `Standardized */ - /* Variation Sequences' and registered `Ideographic Variation */ - /* Sequences' (IVS), collected in the `Ideographic Variation */ - /* Database' (IVD). */ - /* */ - /* https://unicode.org/Public/UCD/latest/ucd/StandardizedVariants.txt */ - /* https://unicode.org/reports/tr37/ */ - /* https://unicode.org/ivd/ */ - /* */ - /* To date (January 2017), the character with the most ideographic */ - /* variations is U+9089, having 32 such IVS. */ - /* */ - /* Three Mongolian Variation Selectors have the values U+180B-U+180D; */ - /* 256 generic Variation Selectors are encoded in the ranges */ - /* U+FE00-U+FE0F and U+E0100-U+E01EF. IVS currently use Variation */ - /* Selectors from the range U+E0100-U+E01EF only. */ - /* */ - /* A VS consists of the base character value followed by a single */ - /* Variation Selector. For example, to get the first variation of */ - /* U+9089, you have to write the character sequence `U+9089 U+E0100'. */ - /* */ - /* Adobe and MS decided to support both standardized and ideographic */ - /* VS with a new cmap subtable (format~14). It is an odd subtable */ - /* because it is not a mapping of input code points to glyphs, but */ - /* contains lists of all variations supported by the font. */ - /* */ - /* A variation may be either `default' or `non-default' for a given */ - /* font. A default variation is the one you will get for that code */ - /* point if you look it up in the standard Unicode cmap. A */ - /* non-default variation is a different glyph. */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * glyph_variants + * + * @title: + * Unicode Variation Sequences + * + * @abstract: + * The FreeType~2 interface to Unicode Variation Sequences (UVS), using + * the SFNT cmap format~14. + * + * @description: + * Many characters, especially for CJK scripts, have variant forms. They + * are a sort of grey area somewhere between being totally irrelevant and + * semantically distinct; for this reason, the Unicode consortium decided + * to introduce Variation Sequences (VS), consisting of a Unicode base + * character and a variation selector instead of further extending the + * already huge number of characters. + * + * Unicode maintains two different sets, namely 'Standardized Variation + * Sequences' and registered 'Ideographic Variation Sequences' (IVS), + * collected in the 'Ideographic Variation Database' (IVD). + * + * https://unicode.org/Public/UCD/latest/ucd/StandardizedVariants.txt + * https://unicode.org/reports/tr37/ https://unicode.org/ivd/ + * + * To date (January 2017), the character with the most ideographic + * variations is U+9089, having 32 such IVS. + * + * Three Mongolian Variation Selectors have the values U+180B-U+180D; 256 + * generic Variation Selectors are encoded in the ranges U+FE00-U+FE0F + * and U+E0100-U+E01EF. IVS currently use Variation Selectors from the + * range U+E0100-U+E01EF only. + * + * A VS consists of the base character value followed by a single + * Variation Selector. For example, to get the first variation of + * U+9089, you have to write the character sequence `U+9089 U+E0100`. + * + * Adobe and MS decided to support both standardized and ideographic VS + * with a new cmap subtable (format~14). It is an odd subtable because + * it is not a mapping of input code points to glyphs, but contains lists + * of all variations supported by the font. + * + * A variation may be either 'default' or 'non-default' for a given font. + * A default variation is the one you will get for that code point if you + * look it up in the standard Unicode cmap. A non-default variation is a + * different glyph. + * + */ - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_GetCharVariantIndex */ - /* */ - /* <Description> */ - /* Return the glyph index of a given character code as modified by */ - /* the variation selector. */ - /* */ - /* <Input> */ - /* face :: */ - /* A handle to the source face object. */ - /* */ - /* charcode :: */ - /* The character code point in Unicode. */ - /* */ - /* variantSelector :: */ - /* The Unicode code point of the variation selector. */ - /* */ - /* <Return> */ - /* The glyph index. 0~means either `undefined character code', or */ - /* `undefined selector code', or `no variation selector cmap */ - /* subtable', or `current CharMap is not Unicode'. */ - /* */ - /* <Note> */ - /* If you use FreeType to manipulate the contents of font files */ - /* directly, be aware that the glyph index returned by this function */ - /* doesn't always correspond to the internal indices used within */ - /* the file. This is done to ensure that value~0 always corresponds */ - /* to the `missing glyph'. */ - /* */ - /* This function is only meaningful if */ - /* a) the font has a variation selector cmap sub table, */ - /* and */ - /* b) the current charmap has a Unicode encoding. */ - /* */ - /* <Since> */ - /* 2.3.6 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_GetCharVariantIndex + * + * @description: + * Return the glyph index of a given character code as modified by the + * variation selector. + * + * @input: + * face :: + * A handle to the source face object. + * + * charcode :: + * The character code point in Unicode. + * + * variantSelector :: + * The Unicode code point of the variation selector. + * + * @return: + * The glyph index. 0~means either 'undefined character code', or + * 'undefined selector code', or 'no variation selector cmap subtable', + * or 'current CharMap is not Unicode'. + * + * @note: + * If you use FreeType to manipulate the contents of font files directly, + * be aware that the glyph index returned by this function doesn't always + * correspond to the internal indices used within the file. This is done + * to ensure that value~0 always corresponds to the 'missing glyph'. + * + * This function is only meaningful if + * a) the font has a variation selector cmap sub table, and + * b) the current charmap has a Unicode encoding. + * + * @since: + * 2.3.6 + */ FT_EXPORT( FT_UInt ) FT_Face_GetCharVariantIndex( FT_Face face, FT_ULong charcode, FT_ULong variantSelector ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_GetCharVariantIsDefault */ - /* */ - /* <Description> */ - /* Check whether this variation of this Unicode character is the one */ - /* to be found in the `cmap'. */ - /* */ - /* <Input> */ - /* face :: */ - /* A handle to the source face object. */ - /* */ - /* charcode :: */ - /* The character codepoint in Unicode. */ - /* */ - /* variantSelector :: */ - /* The Unicode codepoint of the variation selector. */ - /* */ - /* <Return> */ - /* 1~if found in the standard (Unicode) cmap, 0~if found in the */ - /* variation selector cmap, or -1 if it is not a variation. */ - /* */ - /* <Note> */ - /* This function is only meaningful if the font has a variation */ - /* selector cmap subtable. */ - /* */ - /* <Since> */ - /* 2.3.6 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_GetCharVariantIsDefault + * + * @description: + * Check whether this variation of this Unicode character is the one to + * be found in the charmap. + * + * @input: + * face :: + * A handle to the source face object. + * + * charcode :: + * The character codepoint in Unicode. + * + * variantSelector :: + * The Unicode codepoint of the variation selector. + * + * @return: + * 1~if found in the standard (Unicode) cmap, 0~if found in the variation + * selector cmap, or -1 if it is not a variation. + * + * @note: + * This function is only meaningful if the font has a variation selector + * cmap subtable. + * + * @since: + * 2.3.6 + */ FT_EXPORT( FT_Int ) FT_Face_GetCharVariantIsDefault( FT_Face face, FT_ULong charcode, FT_ULong variantSelector ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_GetVariantSelectors */ - /* */ - /* <Description> */ - /* Return a zero-terminated list of Unicode variation selectors found */ - /* in the font. */ - /* */ - /* <Input> */ - /* face :: */ - /* A handle to the source face object. */ - /* */ - /* <Return> */ - /* A pointer to an array of selector code points, or NULL if there is */ - /* no valid variation selector cmap subtable. */ - /* */ - /* <Note> */ - /* The last item in the array is~0; the array is owned by the */ - /* @FT_Face object but can be overwritten or released on the next */ - /* call to a FreeType function. */ - /* */ - /* <Since> */ - /* 2.3.6 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_GetVariantSelectors + * + * @description: + * Return a zero-terminated list of Unicode variation selectors found in + * the font. + * + * @input: + * face :: + * A handle to the source face object. + * + * @return: + * A pointer to an array of selector code points, or `NULL` if there is + * no valid variation selector cmap subtable. + * + * @note: + * The last item in the array is~0; the array is owned by the @FT_Face + * object but can be overwritten or released on the next call to a + * FreeType function. + * + * @since: + * 2.3.6 + */ FT_EXPORT( FT_UInt32* ) FT_Face_GetVariantSelectors( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_GetVariantsOfChar */ - /* */ - /* <Description> */ - /* Return a zero-terminated list of Unicode variation selectors found */ - /* for the specified character code. */ - /* */ - /* <Input> */ - /* face :: */ - /* A handle to the source face object. */ - /* */ - /* charcode :: */ - /* The character codepoint in Unicode. */ - /* */ - /* <Return> */ - /* A pointer to an array of variation selector code points that are */ - /* active for the given character, or NULL if the corresponding list */ - /* is empty. */ - /* */ - /* <Note> */ - /* The last item in the array is~0; the array is owned by the */ - /* @FT_Face object but can be overwritten or released on the next */ - /* call to a FreeType function. */ - /* */ - /* <Since> */ - /* 2.3.6 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_GetVariantsOfChar + * + * @description: + * Return a zero-terminated list of Unicode variation selectors found for + * the specified character code. + * + * @input: + * face :: + * A handle to the source face object. + * + * charcode :: + * The character codepoint in Unicode. + * + * @return: + * A pointer to an array of variation selector code points that are + * active for the given character, or `NULL` if the corresponding list is + * empty. + * + * @note: + * The last item in the array is~0; the array is owned by the @FT_Face + * object but can be overwritten or released on the next call to a + * FreeType function. + * + * @since: + * 2.3.6 + */ FT_EXPORT( FT_UInt32* ) FT_Face_GetVariantsOfChar( FT_Face face, FT_ULong charcode ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_GetCharsOfVariant */ - /* */ - /* <Description> */ - /* Return a zero-terminated list of Unicode character codes found for */ - /* the specified variation selector. */ - /* */ - /* <Input> */ - /* face :: */ - /* A handle to the source face object. */ - /* */ - /* variantSelector :: */ - /* The variation selector code point in Unicode. */ - /* */ - /* <Return> */ - /* A list of all the code points that are specified by this selector */ - /* (both default and non-default codes are returned) or NULL if there */ - /* is no valid cmap or the variation selector is invalid. */ - /* */ - /* <Note> */ - /* The last item in the array is~0; the array is owned by the */ - /* @FT_Face object but can be overwritten or released on the next */ - /* call to a FreeType function. */ - /* */ - /* <Since> */ - /* 2.3.6 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_GetCharsOfVariant + * + * @description: + * Return a zero-terminated list of Unicode character codes found for the + * specified variation selector. + * + * @input: + * face :: + * A handle to the source face object. + * + * variantSelector :: + * The variation selector code point in Unicode. + * + * @return: + * A list of all the code points that are specified by this selector + * (both default and non-default codes are returned) or `NULL` if there + * is no valid cmap or the variation selector is invalid. + * + * @note: + * The last item in the array is~0; the array is owned by the @FT_Face + * object but can be overwritten or released on the next call to a + * FreeType function. + * + * @since: + * 2.3.6 + */ FT_EXPORT( FT_UInt32* ) FT_Face_GetCharsOfVariant( FT_Face face, FT_ULong variantSelector ); - /*************************************************************************/ - /* */ - /* <Section> */ - /* computations */ - /* */ - /* <Title> */ - /* Computations */ - /* */ - /* <Abstract> */ - /* Crunching fixed numbers and vectors. */ - /* */ - /* <Description> */ - /* This section contains various functions used to perform */ - /* computations on 16.16 fixed-float numbers or 2d vectors. */ - /* */ - /* <Order> */ - /* FT_MulDiv */ - /* FT_MulFix */ - /* FT_DivFix */ - /* FT_RoundFix */ - /* FT_CeilFix */ - /* FT_FloorFix */ - /* FT_Vector_Transform */ - /* FT_Matrix_Multiply */ - /* FT_Matrix_Invert */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * computations + * + * @title: + * Computations + * + * @abstract: + * Crunching fixed numbers and vectors. + * + * @description: + * This section contains various functions used to perform computations + * on 16.16 fixed-float numbers or 2d vectors. + * + * **Attention**: Most arithmetic functions take `FT_Long` as arguments. + * For historical reasons, FreeType was designed under the assumption + * that `FT_Long` is a 32-bit integer; results can thus be undefined if + * the arguments don't fit into 32 bits. + * + * @order: + * FT_MulDiv + * FT_MulFix + * FT_DivFix + * FT_RoundFix + * FT_CeilFix + * FT_FloorFix + * FT_Vector_Transform + * FT_Matrix_Multiply + * FT_Matrix_Invert + * + */ - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_MulDiv */ - /* */ - /* <Description> */ - /* Compute `(a*b)/c' with maximum accuracy, using a 64-bit */ - /* intermediate integer whenever necessary. */ - /* */ - /* This function isn't necessarily as fast as some processor specific */ - /* operations, but is at least completely portable. */ - /* */ - /* <Input> */ - /* a :: The first multiplier. */ - /* */ - /* b :: The second multiplier. */ - /* */ - /* c :: The divisor. */ - /* */ - /* <Return> */ - /* The result of `(a*b)/c'. This function never traps when trying to */ - /* divide by zero; it simply returns `MaxInt' or `MinInt' depending */ - /* on the signs of `a' and `b'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_MulDiv + * + * @description: + * Compute `(a*b)/c` with maximum accuracy, using a 64-bit intermediate + * integer whenever necessary. + * + * This function isn't necessarily as fast as some processor-specific + * operations, but is at least completely portable. + * + * @input: + * a :: + * The first multiplier. + * + * b :: + * The second multiplier. + * + * c :: + * The divisor. + * + * @return: + * The result of `(a*b)/c`. This function never traps when trying to + * divide by zero; it simply returns 'MaxInt' or 'MinInt' depending on + * the signs of `a` and `b`. + */ FT_EXPORT( FT_Long ) FT_MulDiv( FT_Long a, FT_Long b, FT_Long c ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_MulFix */ - /* */ - /* <Description> */ - /* Compute `(a*b)/0x10000' with maximum accuracy. Its main use is to */ - /* multiply a given value by a 16.16 fixed-point factor. */ - /* */ - /* <Input> */ - /* a :: The first multiplier. */ - /* */ - /* b :: The second multiplier. Use a 16.16 factor here whenever */ - /* possible (see note below). */ - /* */ - /* <Return> */ - /* The result of `(a*b)/0x10000'. */ - /* */ - /* <Note> */ - /* This function has been optimized for the case where the absolute */ - /* value of `a' is less than 2048, and `b' is a 16.16 scaling factor. */ - /* As this happens mainly when scaling from notional units to */ - /* fractional pixels in FreeType, it resulted in noticeable speed */ - /* improvements between versions 2.x and 1.x. */ - /* */ - /* As a conclusion, always try to place a 16.16 factor as the */ - /* _second_ argument of this function; this can make a great */ - /* difference. */ - /* */ + /************************************************************************** + * + * @function: + * FT_MulFix + * + * @description: + * Compute `(a*b)/0x10000` with maximum accuracy. Its main use is to + * multiply a given value by a 16.16 fixed-point factor. + * + * @input: + * a :: + * The first multiplier. + * + * b :: + * The second multiplier. Use a 16.16 factor here whenever possible + * (see note below). + * + * @return: + * The result of `(a*b)/0x10000`. + * + * @note: + * This function has been optimized for the case where the absolute value + * of `a` is less than 2048, and `b` is a 16.16 scaling factor. As this + * happens mainly when scaling from notional units to fractional pixels + * in FreeType, it resulted in noticeable speed improvements between + * versions 2.x and 1.x. + * + * As a conclusion, always try to place a 16.16 factor as the _second_ + * argument of this function; this can make a great difference. + */ FT_EXPORT( FT_Long ) FT_MulFix( FT_Long a, FT_Long b ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_DivFix */ - /* */ - /* <Description> */ - /* Compute `(a*0x10000)/b' with maximum accuracy. Its main use is to */ - /* divide a given value by a 16.16 fixed-point factor. */ - /* */ - /* <Input> */ - /* a :: The numerator. */ - /* */ - /* b :: The denominator. Use a 16.16 factor here. */ - /* */ - /* <Return> */ - /* The result of `(a*0x10000)/b'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_DivFix + * + * @description: + * Compute `(a*0x10000)/b` with maximum accuracy. Its main use is to + * divide a given value by a 16.16 fixed-point factor. + * + * @input: + * a :: + * The numerator. + * + * b :: + * The denominator. Use a 16.16 factor here. + * + * @return: + * The result of `(a*0x10000)/b`. + */ FT_EXPORT( FT_Long ) FT_DivFix( FT_Long a, FT_Long b ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_RoundFix */ - /* */ - /* <Description> */ - /* Round a 16.16 fixed number. */ - /* */ - /* <Input> */ - /* a :: The number to be rounded. */ - /* */ - /* <Return> */ - /* `a' rounded to the nearest 16.16 fixed integer, halfway cases away */ - /* from zero. */ - /* */ - /* <Note> */ - /* The function uses wrap-around arithmetic. */ - /* */ + /************************************************************************** + * + * @function: + * FT_RoundFix + * + * @description: + * Round a 16.16 fixed number. + * + * @input: + * a :: + * The number to be rounded. + * + * @return: + * `a` rounded to the nearest 16.16 fixed integer, halfway cases away + * from zero. + * + * @note: + * The function uses wrap-around arithmetic. + */ FT_EXPORT( FT_Fixed ) FT_RoundFix( FT_Fixed a ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_CeilFix */ - /* */ - /* <Description> */ - /* Compute the smallest following integer of a 16.16 fixed number. */ - /* */ - /* <Input> */ - /* a :: The number for which the ceiling function is to be computed. */ - /* */ - /* <Return> */ - /* `a' rounded towards plus infinity. */ - /* */ - /* <Note> */ - /* The function uses wrap-around arithmetic. */ - /* */ + /************************************************************************** + * + * @function: + * FT_CeilFix + * + * @description: + * Compute the smallest following integer of a 16.16 fixed number. + * + * @input: + * a :: + * The number for which the ceiling function is to be computed. + * + * @return: + * `a` rounded towards plus infinity. + * + * @note: + * The function uses wrap-around arithmetic. + */ FT_EXPORT( FT_Fixed ) FT_CeilFix( FT_Fixed a ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_FloorFix */ - /* */ - /* <Description> */ - /* Compute the largest previous integer of a 16.16 fixed number. */ - /* */ - /* <Input> */ - /* a :: The number for which the floor function is to be computed. */ - /* */ - /* <Return> */ - /* `a' rounded towards minus infinity. */ - /* */ + /************************************************************************** + * + * @function: + * FT_FloorFix + * + * @description: + * Compute the largest previous integer of a 16.16 fixed number. + * + * @input: + * a :: + * The number for which the floor function is to be computed. + * + * @return: + * `a` rounded towards minus infinity. + */ FT_EXPORT( FT_Fixed ) FT_FloorFix( FT_Fixed a ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Vector_Transform */ - /* */ - /* <Description> */ - /* Transform a single vector through a 2x2 matrix. */ - /* */ - /* <InOut> */ - /* vector :: The target vector to transform. */ - /* */ - /* <Input> */ - /* matrix :: A pointer to the source 2x2 matrix. */ - /* */ - /* <Note> */ - /* The result is undefined if either `vector' or `matrix' is invalid. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Vector_Transform + * + * @description: + * Transform a single vector through a 2x2 matrix. + * + * @inout: + * vector :: + * The target vector to transform. + * + * @input: + * matrix :: + * A pointer to the source 2x2 matrix. + * + * @note: + * The result is undefined if either `vector` or `matrix` is invalid. + */ FT_EXPORT( void ) - FT_Vector_Transform( FT_Vector* vec, + FT_Vector_Transform( FT_Vector* vector, const FT_Matrix* matrix ); - /*************************************************************************/ - /* */ - /* <Section> */ - /* version */ - /* */ - /* <Title> */ - /* FreeType Version */ - /* */ - /* <Abstract> */ - /* Functions and macros related to FreeType versions. */ - /* */ - /* <Description> */ - /* Note that those functions and macros are of limited use because */ - /* even a new release of FreeType with only documentation changes */ - /* increases the version number. */ - /* */ - /* <Order> */ - /* FT_Library_Version */ - /* */ - /* FREETYPE_MAJOR */ - /* FREETYPE_MINOR */ - /* FREETYPE_PATCH */ - /* */ - /* FT_Face_CheckTrueTypePatents */ - /* FT_Face_SetUnpatentedHinting */ - /* */ - /* FREETYPE_XXX */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * @section: + * version + * + * @title: + * FreeType Version + * + * @abstract: + * Functions and macros related to FreeType versions. + * + * @description: + * Note that those functions and macros are of limited use because even a + * new release of FreeType with only documentation changes increases the + * version number. + * + * @order: + * FT_Library_Version + * + * FREETYPE_MAJOR + * FREETYPE_MINOR + * FREETYPE_PATCH + * + * FT_Face_CheckTrueTypePatents + * FT_Face_SetUnpatentedHinting + * + */ - /************************************************************************* + /************************************************************************** * * @enum: * FREETYPE_XXX * * @description: - * These three macros identify the FreeType source code version. - * Use @FT_Library_Version to access them at runtime. + * These three macros identify the FreeType source code version. Use + * @FT_Library_Version to access them at runtime. * * @values: - * FREETYPE_MAJOR :: The major version number. - * FREETYPE_MINOR :: The minor version number. - * FREETYPE_PATCH :: The patch level. + * FREETYPE_MAJOR :: + * The major version number. + * FREETYPE_MINOR :: + * The minor version number. + * FREETYPE_PATCH :: + * The patch level. * * @note: - * The version number of FreeType if built as a dynamic link library - * with the `libtool' package is _not_ controlled by these three - * macros. + * The version number of FreeType if built as a dynamic link library with + * the 'libtool' package is _not_ controlled by these three macros. * */ #define FREETYPE_MAJOR 2 -#define FREETYPE_MINOR 9 -#define FREETYPE_PATCH 1 +#define FREETYPE_MINOR 10 +#define FREETYPE_PATCH 0 - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Library_Version */ - /* */ - /* <Description> */ - /* Return the version of the FreeType library being used. This is */ - /* useful when dynamically linking to the library, since one cannot */ - /* use the macros @FREETYPE_MAJOR, @FREETYPE_MINOR, and */ - /* @FREETYPE_PATCH. */ - /* */ - /* <Input> */ - /* library :: A source library handle. */ - /* */ - /* <Output> */ - /* amajor :: The major version number. */ - /* */ - /* aminor :: The minor version number. */ - /* */ - /* apatch :: The patch version number. */ - /* */ - /* <Note> */ - /* The reason why this function takes a `library' argument is because */ - /* certain programs implement library initialization in a custom way */ - /* that doesn't use @FT_Init_FreeType. */ - /* */ - /* In such cases, the library version might not be available before */ - /* the library object has been created. */ - /* */ + /************************************************************************** + * + * @function: + * FT_Library_Version + * + * @description: + * Return the version of the FreeType library being used. This is useful + * when dynamically linking to the library, since one cannot use the + * macros @FREETYPE_MAJOR, @FREETYPE_MINOR, and @FREETYPE_PATCH. + * + * @input: + * library :: + * A source library handle. + * + * @output: + * amajor :: + * The major version number. + * + * aminor :: + * The minor version number. + * + * apatch :: + * The patch version number. + * + * @note: + * The reason why this function takes a `library` argument is because + * certain programs implement library initialization in a custom way that + * doesn't use @FT_Init_FreeType. + * + * In such cases, the library version might not be available before the + * library object has been created. + */ FT_EXPORT( void ) FT_Library_Version( FT_Library library, FT_Int *amajor, @@ -4596,52 +4816,55 @@ FT_BEGIN_HEADER FT_Int *apatch ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_CheckTrueTypePatents */ - /* */ - /* <Description> */ - /* Deprecated, does nothing. */ - /* */ - /* <Input> */ - /* face :: A face handle. */ - /* */ - /* <Return> */ - /* Always returns false. */ - /* */ - /* <Note> */ - /* Since May 2010, TrueType hinting is no longer patented. */ - /* */ - /* <Since> */ - /* 2.3.5 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_CheckTrueTypePatents + * + * @description: + * Deprecated, does nothing. + * + * @input: + * face :: + * A face handle. + * + * @return: + * Always returns false. + * + * @note: + * Since May 2010, TrueType hinting is no longer patented. + * + * @since: + * 2.3.5 + */ FT_EXPORT( FT_Bool ) FT_Face_CheckTrueTypePatents( FT_Face face ); - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_Face_SetUnpatentedHinting */ - /* */ - /* <Description> */ - /* Deprecated, does nothing. */ - /* */ - /* <Input> */ - /* face :: A face handle. */ - /* */ - /* value :: New boolean setting. */ - /* */ - /* <Return> */ - /* Always returns false. */ - /* */ - /* <Note> */ - /* Since May 2010, TrueType hinting is no longer patented. */ - /* */ - /* <Since> */ - /* 2.3.5 */ - /* */ + /************************************************************************** + * + * @function: + * FT_Face_SetUnpatentedHinting + * + * @description: + * Deprecated, does nothing. + * + * @input: + * face :: + * A face handle. + * + * value :: + * New boolean setting. + * + * @return: + * Always returns false. + * + * @note: + * Since May 2010, TrueType hinting is no longer patented. + * + * @since: + * 2.3.5 + */ FT_EXPORT( FT_Bool ) FT_Face_SetUnpatentedHinting( FT_Face face, FT_Bool value ); |