diff options
Diffstat (limited to 'Build/source/libs/freetype2/freetype-2.4.9/src/smooth/ftgrays.c')
-rw-r--r-- | Build/source/libs/freetype2/freetype-2.4.9/src/smooth/ftgrays.c | 2066 |
1 files changed, 2066 insertions, 0 deletions
diff --git a/Build/source/libs/freetype2/freetype-2.4.9/src/smooth/ftgrays.c b/Build/source/libs/freetype2/freetype-2.4.9/src/smooth/ftgrays.c new file mode 100644 index 00000000000..4c0eea596d5 --- /dev/null +++ b/Build/source/libs/freetype2/freetype-2.4.9/src/smooth/ftgrays.c @@ -0,0 +1,2066 @@ +/***************************************************************************/ +/* */ +/* ftgrays.c */ +/* */ +/* A new `perfect' anti-aliasing renderer (body). */ +/* */ +/* Copyright 2000-2003, 2005-2012 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. */ +/* */ +/***************************************************************************/ + + /*************************************************************************/ + /* */ + /* This file can be compiled without the rest of the FreeType engine, by */ + /* defining the _STANDALONE_ macro when compiling it. You also need to */ + /* put the files `ftgrays.h' and `ftimage.h' into the current */ + /* compilation directory. Typically, you could do something like */ + /* */ + /* - copy `src/smooth/ftgrays.c' (this file) to your current directory */ + /* */ + /* - copy `include/freetype/ftimage.h' and `src/smooth/ftgrays.h' to the */ + /* same directory */ + /* */ + /* - compile `ftgrays' with the _STANDALONE_ macro defined, as in */ + /* */ + /* cc -c -D_STANDALONE_ ftgrays.c */ + /* */ + /* The renderer can be initialized with a call to */ + /* `ft_gray_raster.raster_new'; an anti-aliased bitmap can be generated */ + /* with a call to `ft_gray_raster.raster_render'. */ + /* */ + /* See the comments and documentation in the file `ftimage.h' for more */ + /* details on how the raster works. */ + /* */ + /*************************************************************************/ + + /*************************************************************************/ + /* */ + /* This is a new anti-aliasing scan-converter for FreeType 2. The */ + /* algorithm used here is _very_ different from the one in the standard */ + /* `ftraster' module. Actually, `ftgrays' computes the _exact_ */ + /* coverage of the outline on each pixel cell. */ + /* */ + /* It is based on ideas that I initially found in Raph Levien's */ + /* excellent LibArt graphics library (see http://www.levien.com/libart */ + /* for more information, though the web pages do not tell anything */ + /* about the renderer; you'll have to dive into the source code to */ + /* understand how it works). */ + /* */ + /* Note, however, that this is a _very_ different implementation */ + /* compared to Raph's. Coverage information is stored in a very */ + /* different way, and I don't use sorted vector paths. Also, it doesn't */ + /* use floating point values. */ + /* */ + /* This renderer has the following advantages: */ + /* */ + /* - It doesn't need an intermediate bitmap. Instead, one can supply a */ + /* callback function that will be called by the renderer to draw gray */ + /* spans on any target surface. You can thus do direct composition on */ + /* any kind of bitmap, provided that you give the renderer the right */ + /* callback. */ + /* */ + /* - A perfect anti-aliaser, i.e., it computes the _exact_ coverage on */ + /* each pixel cell. */ + /* */ + /* - It performs a single pass on the outline (the `standard' FT2 */ + /* renderer makes two passes). */ + /* */ + /* - It can easily be modified to render to _any_ number of gray levels */ + /* cheaply. */ + /* */ + /* - For small (< 20) pixel sizes, it is faster than the standard */ + /* renderer. */ + /* */ + /*************************************************************************/ + + + /*************************************************************************/ + /* */ + /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ + /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ + /* messages during execution. */ + /* */ +#undef FT_COMPONENT +#define FT_COMPONENT trace_smooth + + +#ifdef _STANDALONE_ + + + /* define this to dump debugging information */ +/* #define FT_DEBUG_LEVEL_TRACE */ + + +#ifdef FT_DEBUG_LEVEL_TRACE +#include <stdio.h> +#include <stdarg.h> +#endif + +#include <stddef.h> +#include <string.h> +#include <setjmp.h> +#include <limits.h> +#define FT_UINT_MAX UINT_MAX +#define FT_INT_MAX INT_MAX + +#define ft_memset memset + +#define ft_setjmp setjmp +#define ft_longjmp longjmp +#define ft_jmp_buf jmp_buf + +typedef ptrdiff_t FT_PtrDist; + + +#define ErrRaster_Invalid_Mode -2 +#define ErrRaster_Invalid_Outline -1 +#define ErrRaster_Invalid_Argument -3 +#define ErrRaster_Memory_Overflow -4 + +#define FT_BEGIN_HEADER +#define FT_END_HEADER + +#include "ftimage.h" +#include "ftgrays.h" + + + /* This macro is used to indicate that a function parameter is unused. */ + /* Its purpose is simply to reduce compiler warnings. Note also that */ + /* simply defining it as `(void)x' doesn't avoid warnings with certain */ + /* ANSI compilers (e.g. LCC). */ +#define FT_UNUSED( x ) (x) = (x) + + + /* we only use level 5 & 7 tracing messages; cf. ftdebug.h */ + +#ifdef FT_DEBUG_LEVEL_TRACE + + void + FT_Message( const char* fmt, + ... ) + { + va_list ap; + + + va_start( ap, fmt ); + vfprintf( stderr, fmt, ap ); + va_end( ap ); + } + + /* we don't handle tracing levels in stand-alone mode; */ +#ifndef FT_TRACE5 +#define FT_TRACE5( varformat ) FT_Message varformat +#endif +#ifndef FT_TRACE7 +#define FT_TRACE7( varformat ) FT_Message varformat +#endif +#ifndef FT_ERROR +#define FT_ERROR( varformat ) FT_Message varformat +#endif + +#else /* !FT_DEBUG_LEVEL_TRACE */ + +#define FT_TRACE5( x ) do { } while ( 0 ) /* nothing */ +#define FT_TRACE7( x ) do { } while ( 0 ) /* nothing */ +#define FT_ERROR( x ) do { } while ( 0 ) /* nothing */ + +#endif /* !FT_DEBUG_LEVEL_TRACE */ + + +#define FT_DEFINE_OUTLINE_FUNCS( class_, \ + move_to_, line_to_, \ + conic_to_, cubic_to_, \ + shift_, delta_ ) \ + static const FT_Outline_Funcs class_ = \ + { \ + move_to_, \ + line_to_, \ + conic_to_, \ + cubic_to_, \ + shift_, \ + delta_ \ + }; + +#define FT_DEFINE_RASTER_FUNCS( class_, glyph_format_, \ + raster_new_, raster_reset_, \ + raster_set_mode_, raster_render_, \ + raster_done_ ) \ + const FT_Raster_Funcs class_ = \ + { \ + glyph_format_, \ + raster_new_, \ + raster_reset_, \ + raster_set_mode_, \ + raster_render_, \ + raster_done_ \ + }; + +#else /* !_STANDALONE_ */ + + +#include <ft2build.h> +#include "ftgrays.h" +#include FT_INTERNAL_OBJECTS_H +#include FT_INTERNAL_DEBUG_H +#include FT_OUTLINE_H + +#include "ftsmerrs.h" + +#include "ftspic.h" + +#define ErrRaster_Invalid_Mode Smooth_Err_Cannot_Render_Glyph +#define ErrRaster_Invalid_Outline Smooth_Err_Invalid_Outline +#define ErrRaster_Memory_Overflow Smooth_Err_Out_Of_Memory +#define ErrRaster_Invalid_Argument Smooth_Err_Invalid_Argument + +#endif /* !_STANDALONE_ */ + +#ifndef FT_MEM_SET +#define FT_MEM_SET( d, s, c ) ft_memset( d, s, c ) +#endif + +#ifndef FT_MEM_ZERO +#define FT_MEM_ZERO( dest, count ) FT_MEM_SET( dest, 0, count ) +#endif + + /* as usual, for the speed hungry :-) */ + +#undef RAS_ARG +#undef RAS_ARG_ +#undef RAS_VAR +#undef RAS_VAR_ + +#ifndef FT_STATIC_RASTER + +#define RAS_ARG gray_PWorker worker +#define RAS_ARG_ gray_PWorker worker, + +#define RAS_VAR worker +#define RAS_VAR_ worker, + +#else /* FT_STATIC_RASTER */ + +#define RAS_ARG /* empty */ +#define RAS_ARG_ /* empty */ +#define RAS_VAR /* empty */ +#define RAS_VAR_ /* empty */ + +#endif /* FT_STATIC_RASTER */ + + + /* must be at least 6 bits! */ +#define PIXEL_BITS 8 + +#undef FLOOR +#undef CEILING +#undef TRUNC +#undef SCALED + +#define ONE_PIXEL ( 1L << PIXEL_BITS ) +#define PIXEL_MASK ( -1L << PIXEL_BITS ) +#define TRUNC( x ) ( (TCoord)( (x) >> PIXEL_BITS ) ) +#define SUBPIXELS( x ) ( (TPos)(x) << PIXEL_BITS ) +#define FLOOR( x ) ( (x) & -ONE_PIXEL ) +#define CEILING( x ) ( ( (x) + ONE_PIXEL - 1 ) & -ONE_PIXEL ) +#define ROUND( x ) ( ( (x) + ONE_PIXEL / 2 ) & -ONE_PIXEL ) + +#if PIXEL_BITS >= 6 +#define UPSCALE( x ) ( (x) << ( PIXEL_BITS - 6 ) ) +#define DOWNSCALE( x ) ( (x) >> ( PIXEL_BITS - 6 ) ) +#else +#define UPSCALE( x ) ( (x) >> ( 6 - PIXEL_BITS ) ) +#define DOWNSCALE( x ) ( (x) << ( 6 - PIXEL_BITS ) ) +#endif + + + /*************************************************************************/ + /* */ + /* TYPE DEFINITIONS */ + /* */ + + /* don't change the following types to FT_Int or FT_Pos, since we might */ + /* need to define them to "float" or "double" when experimenting with */ + /* new algorithms */ + + typedef long TCoord; /* integer scanline/pixel coordinate */ + typedef long TPos; /* sub-pixel coordinate */ + + /* determine the type used to store cell areas. This normally takes at */ + /* least PIXEL_BITS*2 + 1 bits. On 16-bit systems, we need to use */ + /* `long' instead of `int', otherwise bad things happen */ + +#if PIXEL_BITS <= 7 + + typedef int TArea; + +#else /* PIXEL_BITS >= 8 */ + + /* approximately determine the size of integers using an ANSI-C header */ +#if FT_UINT_MAX == 0xFFFFU + typedef long TArea; +#else + typedef int TArea; +#endif + +#endif /* PIXEL_BITS >= 8 */ + + + /* maximal number of gray spans in a call to the span callback */ +#define FT_MAX_GRAY_SPANS 32 + + + typedef struct TCell_* PCell; + + typedef struct TCell_ + { + TPos x; /* same with gray_TWorker.ex */ + TCoord cover; /* same with gray_TWorker.cover */ + TArea area; + PCell next; + + } TCell; + + + typedef struct gray_TWorker_ + { + TCoord ex, ey; + TPos min_ex, max_ex; + TPos min_ey, max_ey; + TPos count_ex, count_ey; + + TArea area; + TCoord cover; + int invalid; + + PCell cells; + FT_PtrDist max_cells; + FT_PtrDist num_cells; + + TCoord cx, cy; + TPos x, y; + + TPos last_ey; + + FT_Vector bez_stack[32 * 3 + 1]; + int lev_stack[32]; + + FT_Outline outline; + FT_Bitmap target; + FT_BBox clip_box; + + FT_Span gray_spans[FT_MAX_GRAY_SPANS]; + int num_gray_spans; + + FT_Raster_Span_Func render_span; + void* render_span_data; + int span_y; + + int band_size; + int band_shoot; + + ft_jmp_buf jump_buffer; + + void* buffer; + long buffer_size; + + PCell* ycells; + TPos ycount; + + } gray_TWorker, *gray_PWorker; + + +#ifndef FT_STATIC_RASTER +#define ras (*worker) +#else + static gray_TWorker ras; +#endif + + + typedef struct gray_TRaster_ + { + void* buffer; + long buffer_size; + int band_size; + void* memory; + gray_PWorker worker; + + } gray_TRaster, *gray_PRaster; + + + + /*************************************************************************/ + /* */ + /* Initialize the cells table. */ + /* */ + static void + gray_init_cells( RAS_ARG_ void* buffer, + long byte_size ) + { + ras.buffer = buffer; + ras.buffer_size = byte_size; + + ras.ycells = (PCell*) buffer; + ras.cells = NULL; + ras.max_cells = 0; + ras.num_cells = 0; + ras.area = 0; + ras.cover = 0; + ras.invalid = 1; + } + + + /*************************************************************************/ + /* */ + /* Compute the outline bounding box. */ + /* */ + static void + gray_compute_cbox( RAS_ARG ) + { + FT_Outline* outline = &ras.outline; + FT_Vector* vec = outline->points; + FT_Vector* limit = vec + outline->n_points; + + + if ( outline->n_points <= 0 ) + { + ras.min_ex = ras.max_ex = 0; + ras.min_ey = ras.max_ey = 0; + return; + } + + ras.min_ex = ras.max_ex = vec->x; + ras.min_ey = ras.max_ey = vec->y; + + vec++; + + for ( ; vec < limit; vec++ ) + { + TPos x = vec->x; + TPos y = vec->y; + + + if ( x < ras.min_ex ) ras.min_ex = x; + if ( x > ras.max_ex ) ras.max_ex = x; + if ( y < ras.min_ey ) ras.min_ey = y; + if ( y > ras.max_ey ) ras.max_ey = y; + } + + /* truncate the bounding box to integer pixels */ + ras.min_ex = ras.min_ex >> 6; + ras.min_ey = ras.min_ey >> 6; + ras.max_ex = ( ras.max_ex + 63 ) >> 6; + ras.max_ey = ( ras.max_ey + 63 ) >> 6; + } + + + /*************************************************************************/ + /* */ + /* Record the current cell in the table. */ + /* */ + static PCell + gray_find_cell( RAS_ARG ) + { + PCell *pcell, cell; + TPos x = ras.ex; + + + if ( x > ras.count_ex ) + x = ras.count_ex; + + pcell = &ras.ycells[ras.ey]; + for (;;) + { + cell = *pcell; + if ( cell == NULL || cell->x > x ) + break; + + if ( cell->x == x ) + goto Exit; + + pcell = &cell->next; + } + + if ( ras.num_cells >= ras.max_cells ) + ft_longjmp( ras.jump_buffer, 1 ); + + cell = ras.cells + ras.num_cells++; + cell->x = x; + cell->area = 0; + cell->cover = 0; + + cell->next = *pcell; + *pcell = cell; + + Exit: + return cell; + } + + + static void + gray_record_cell( RAS_ARG ) + { + if ( !ras.invalid && ( ras.area | ras.cover ) ) + { + PCell cell = gray_find_cell( RAS_VAR ); + + + cell->area += ras.area; + cell->cover += ras.cover; + } + } + + + /*************************************************************************/ + /* */ + /* Set the current cell to a new position. */ + /* */ + static void + gray_set_cell( RAS_ARG_ TCoord ex, + TCoord ey ) + { + /* Move the cell pointer to a new position. We set the `invalid' */ + /* flag to indicate that the cell isn't part of those we're interested */ + /* in during the render phase. This means that: */ + /* */ + /* . the new vertical position must be within min_ey..max_ey-1. */ + /* . the new horizontal position must be strictly less than max_ex */ + /* */ + /* Note that if a cell is to the left of the clipping region, it is */ + /* actually set to the (min_ex-1) horizontal position. */ + + /* All cells that are on the left of the clipping region go to the */ + /* min_ex - 1 horizontal position. */ + ey -= ras.min_ey; + + if ( ex > ras.max_ex ) + ex = ras.max_ex; + + ex -= ras.min_ex; + if ( ex < 0 ) + ex = -1; + + /* are we moving to a different cell ? */ + if ( ex != ras.ex || ey != ras.ey ) + { + /* record the current one if it is valid */ + if ( !ras.invalid ) + gray_record_cell( RAS_VAR ); + + ras.area = 0; + ras.cover = 0; + } + + ras.ex = ex; + ras.ey = ey; + ras.invalid = ( (unsigned)ey >= (unsigned)ras.count_ey || + ex >= ras.count_ex ); + } + + + /*************************************************************************/ + /* */ + /* Start a new contour at a given cell. */ + /* */ + static void + gray_start_cell( RAS_ARG_ TCoord ex, + TCoord ey ) + { + if ( ex > ras.max_ex ) + ex = (TCoord)( ras.max_ex ); + + if ( ex < ras.min_ex ) + ex = (TCoord)( ras.min_ex - 1 ); + + ras.area = 0; + ras.cover = 0; + ras.ex = ex - ras.min_ex; + ras.ey = ey - ras.min_ey; + ras.last_ey = SUBPIXELS( ey ); + ras.invalid = 0; + + gray_set_cell( RAS_VAR_ ex, ey ); + } + + + /*************************************************************************/ + /* */ + /* Render a scanline as one or more cells. */ + /* */ + static void + gray_render_scanline( RAS_ARG_ TCoord ey, + TPos x1, + TCoord y1, + TPos x2, + TCoord y2 ) + { + TCoord ex1, ex2, fx1, fx2, delta, mod, lift, rem; + long p, first, dx; + int incr; + + + dx = x2 - x1; + + ex1 = TRUNC( x1 ); + ex2 = TRUNC( x2 ); + fx1 = (TCoord)( x1 - SUBPIXELS( ex1 ) ); + fx2 = (TCoord)( x2 - SUBPIXELS( ex2 ) ); + + /* trivial case. Happens often */ + if ( y1 == y2 ) + { + gray_set_cell( RAS_VAR_ ex2, ey ); + return; + } + + /* everything is located in a single cell. That is easy! */ + /* */ + if ( ex1 == ex2 ) + { + delta = y2 - y1; + ras.area += (TArea)(( fx1 + fx2 ) * delta); + ras.cover += delta; + return; + } + + /* ok, we'll have to render a run of adjacent cells on the same */ + /* scanline... */ + /* */ + p = ( ONE_PIXEL - fx1 ) * ( y2 - y1 ); + first = ONE_PIXEL; + incr = 1; + + if ( dx < 0 ) + { + p = fx1 * ( y2 - y1 ); + first = 0; + incr = -1; + dx = -dx; + } + + delta = (TCoord)( p / dx ); + mod = (TCoord)( p % dx ); + if ( mod < 0 ) + { + delta--; + mod += (TCoord)dx; + } + + ras.area += (TArea)(( fx1 + first ) * delta); + ras.cover += delta; + + ex1 += incr; + gray_set_cell( RAS_VAR_ ex1, ey ); + y1 += delta; + + if ( ex1 != ex2 ) + { + p = ONE_PIXEL * ( y2 - y1 + delta ); + lift = (TCoord)( p / dx ); + rem = (TCoord)( p % dx ); + if ( rem < 0 ) + { + lift--; + rem += (TCoord)dx; + } + + mod -= (int)dx; + + while ( ex1 != ex2 ) + { + delta = lift; + mod += rem; + if ( mod >= 0 ) + { + mod -= (TCoord)dx; + delta++; + } + + ras.area += (TArea)(ONE_PIXEL * delta); + ras.cover += delta; + y1 += delta; + ex1 += incr; + gray_set_cell( RAS_VAR_ ex1, ey ); + } + } + + delta = y2 - y1; + ras.area += (TArea)(( fx2 + ONE_PIXEL - first ) * delta); + ras.cover += delta; + } + + + /*************************************************************************/ + /* */ + /* Render a given line as a series of scanlines. */ + /* */ + static void + gray_render_line( RAS_ARG_ TPos to_x, + TPos to_y ) + { + TCoord ey1, ey2, fy1, fy2, mod; + TPos dx, dy, x, x2; + long p, first; + int delta, rem, lift, incr; + + + ey1 = TRUNC( ras.last_ey ); + ey2 = TRUNC( to_y ); /* if (ey2 >= ras.max_ey) ey2 = ras.max_ey-1; */ + fy1 = (TCoord)( ras.y - ras.last_ey ); + fy2 = (TCoord)( to_y - SUBPIXELS( ey2 ) ); + + dx = to_x - ras.x; + dy = to_y - ras.y; + + /* XXX: we should do something about the trivial case where dx == 0, */ + /* as it happens very often! */ + + /* perform vertical clipping */ + { + TCoord min, max; + + + min = ey1; + max = ey2; + if ( ey1 > ey2 ) + { + min = ey2; + max = ey1; + } + if ( min >= ras.max_ey || max < ras.min_ey ) + goto End; + } + + /* everything is on a single scanline */ + if ( ey1 == ey2 ) + { + gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, to_x, fy2 ); + goto End; + } + + /* vertical line - avoid calling gray_render_scanline */ + incr = 1; + + if ( dx == 0 ) + { + TCoord ex = TRUNC( ras.x ); + TCoord two_fx = (TCoord)( ( ras.x - SUBPIXELS( ex ) ) << 1 ); + TArea area; + + + first = ONE_PIXEL; + if ( dy < 0 ) + { + first = 0; + incr = -1; + } + + delta = (int)( first - fy1 ); + ras.area += (TArea)two_fx * delta; + ras.cover += delta; + ey1 += incr; + + gray_set_cell( RAS_VAR_ ex, ey1 ); + + delta = (int)( first + first - ONE_PIXEL ); + area = (TArea)two_fx * delta; + while ( ey1 != ey2 ) + { + ras.area += area; + ras.cover += delta; + ey1 += incr; + + gray_set_cell( RAS_VAR_ ex, ey1 ); + } + + delta = (int)( fy2 - ONE_PIXEL + first ); + ras.area += (TArea)two_fx * delta; + ras.cover += delta; + + goto End; + } + + /* ok, we have to render several scanlines */ + p = ( ONE_PIXEL - fy1 ) * dx; + first = ONE_PIXEL; + incr = 1; + + if ( dy < 0 ) + { + p = fy1 * dx; + first = 0; + incr = -1; + dy = -dy; + } + + delta = (int)( p / dy ); + mod = (int)( p % dy ); + if ( mod < 0 ) + { + delta--; + mod += (TCoord)dy; + } + + x = ras.x + delta; + gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, x, (TCoord)first ); + + ey1 += incr; + gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 ); + + if ( ey1 != ey2 ) + { + p = ONE_PIXEL * dx; + lift = (int)( p / dy ); + rem = (int)( p % dy ); + if ( rem < 0 ) + { + lift--; + rem += (int)dy; + } + mod -= (int)dy; + + while ( ey1 != ey2 ) + { + delta = lift; + mod += rem; + if ( mod >= 0 ) + { + mod -= (int)dy; + delta++; + } + + x2 = x + delta; + gray_render_scanline( RAS_VAR_ ey1, x, + (TCoord)( ONE_PIXEL - first ), x2, + (TCoord)first ); + x = x2; + + ey1 += incr; + gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 ); + } + } + + gray_render_scanline( RAS_VAR_ ey1, x, + (TCoord)( ONE_PIXEL - first ), to_x, + fy2 ); + + End: + ras.x = to_x; + ras.y = to_y; + ras.last_ey = SUBPIXELS( ey2 ); + } + + + static void + gray_split_conic( FT_Vector* base ) + { + TPos a, b; + + + base[4].x = base[2].x; + b = base[1].x; + a = base[3].x = ( base[2].x + b ) / 2; + b = base[1].x = ( base[0].x + b ) / 2; + base[2].x = ( a + b ) / 2; + + base[4].y = base[2].y; + b = base[1].y; + a = base[3].y = ( base[2].y + b ) / 2; + b = base[1].y = ( base[0].y + b ) / 2; + base[2].y = ( a + b ) / 2; + } + + + static void + gray_render_conic( RAS_ARG_ const FT_Vector* control, + const FT_Vector* to ) + { + TPos dx, dy; + TPos min, max, y; + int top, level; + int* levels; + FT_Vector* arc; + + + levels = ras.lev_stack; + + arc = ras.bez_stack; + arc[0].x = UPSCALE( to->x ); + arc[0].y = UPSCALE( to->y ); + arc[1].x = UPSCALE( control->x ); + arc[1].y = UPSCALE( control->y ); + arc[2].x = ras.x; + arc[2].y = ras.y; + top = 0; + + dx = FT_ABS( arc[2].x + arc[0].x - 2 * arc[1].x ); + dy = FT_ABS( arc[2].y + arc[0].y - 2 * arc[1].y ); + if ( dx < dy ) + dx = dy; + + if ( dx < ONE_PIXEL / 4 ) + goto Draw; + + /* short-cut the arc that crosses the current band */ + min = max = arc[0].y; + + y = arc[1].y; + if ( y < min ) min = y; + if ( y > max ) max = y; + + y = arc[2].y; + if ( y < min ) min = y; + if ( y > max ) max = y; + + if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey ) + goto Draw; + + level = 0; + do + { + dx >>= 2; + level++; + } while ( dx > ONE_PIXEL / 4 ); + + levels[0] = level; + + do + { + level = levels[top]; + if ( level > 0 ) + { + gray_split_conic( arc ); + arc += 2; + top++; + levels[top] = levels[top - 1] = level - 1; + continue; + } + + Draw: + gray_render_line( RAS_VAR_ arc[0].x, arc[0].y ); + top--; + arc -= 2; + + } while ( top >= 0 ); + } + + + static void + gray_split_cubic( FT_Vector* base ) + { + TPos a, b, c, d; + + + base[6].x = base[3].x; + c = base[1].x; + d = base[2].x; + base[1].x = a = ( base[0].x + c ) / 2; + base[5].x = b = ( base[3].x + d ) / 2; + c = ( c + d ) / 2; + base[2].x = a = ( a + c ) / 2; + base[4].x = b = ( b + c ) / 2; + base[3].x = ( a + b ) / 2; + + base[6].y = base[3].y; + c = base[1].y; + d = base[2].y; + base[1].y = a = ( base[0].y + c ) / 2; + base[5].y = b = ( base[3].y + d ) / 2; + c = ( c + d ) / 2; + base[2].y = a = ( a + c ) / 2; + base[4].y = b = ( b + c ) / 2; + base[3].y = ( a + b ) / 2; + } + + + static void + gray_render_cubic( RAS_ARG_ const FT_Vector* control1, + const FT_Vector* control2, + const FT_Vector* to ) + { + FT_Vector* arc; + TPos min, max, y; + + + arc = ras.bez_stack; + arc[0].x = UPSCALE( to->x ); + arc[0].y = UPSCALE( to->y ); + arc[1].x = UPSCALE( control2->x ); + arc[1].y = UPSCALE( control2->y ); + arc[2].x = UPSCALE( control1->x ); + arc[2].y = UPSCALE( control1->y ); + arc[3].x = ras.x; + arc[3].y = ras.y; + + /* Short-cut the arc that crosses the current band. */ + min = max = arc[0].y; + + y = arc[1].y; + if ( y < min ) + min = y; + if ( y > max ) + max = y; + + y = arc[2].y; + if ( y < min ) + min = y; + if ( y > max ) + max = y; + + y = arc[3].y; + if ( y < min ) + min = y; + if ( y > max ) + max = y; + + if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey ) + goto Draw; + + for (;;) + { + /* Decide whether to split or draw. See `Rapid Termination */ + /* Evaluation for Recursive Subdivision of Bezier Curves' by Thomas */ + /* F. Hain, at */ + /* http://www.cis.southalabama.edu/~hain/general/Publications/Bezier/Camera-ready%20CISST02%202.pdf */ + + { + TPos dx, dy, dx_, dy_; + TPos dx1, dy1, dx2, dy2; + TPos L, s, s_limit; + + + /* dx and dy are x and y components of the P0-P3 chord vector. */ + dx = arc[3].x - arc[0].x; + dy = arc[3].y - arc[0].y; + + /* L is an (under)estimate of the Euclidean distance P0-P3. */ + /* */ + /* If dx >= dy, then r = sqrt(dx^2 + dy^2) can be overestimated */ + /* with least maximum error by */ + /* */ + /* r_upperbound = dx + (sqrt(2) - 1) * dy , */ + /* */ + /* where sqrt(2) - 1 can be (over)estimated by 107/256, giving an */ + /* error of no more than 8.4%. */ + /* */ + /* Similarly, some elementary calculus shows that r can be */ + /* underestimated with least maximum error by */ + /* */ + /* r_lowerbound = sqrt(2 + sqrt(2)) / 2 * dx */ + /* + sqrt(2 - sqrt(2)) / 2 * dy . */ + /* */ + /* 236/256 and 97/256 are (under)estimates of the two algebraic */ + /* numbers, giving an error of no more than 8.1%. */ + + dx_ = FT_ABS( dx ); + dy_ = FT_ABS( dy ); + + /* This is the same as */ + /* */ + /* L = ( 236 * FT_MAX( dx_, dy_ ) */ + /* + 97 * FT_MIN( dx_, dy_ ) ) >> 8; */ + L = ( dx_ > dy_ ? 236 * dx_ + 97 * dy_ + : 97 * dx_ + 236 * dy_ ) >> 8; + + /* Avoid possible arithmetic overflow below by splitting. */ + if ( L > 32767 ) + goto Split; + + /* Max deviation may be as much as (s/L) * 3/4 (if Hain's v = 1). */ + s_limit = L * (TPos)( ONE_PIXEL / 6 ); + + /* s is L * the perpendicular distance from P1 to the line P0-P3. */ + dx1 = arc[1].x - arc[0].x; + dy1 = arc[1].y - arc[0].y; + s = FT_ABS( dy * dx1 - dx * dy1 ); + + if ( s > s_limit ) + goto Split; + + /* s is L * the perpendicular distance from P2 to the line P0-P3. */ + dx2 = arc[2].x - arc[0].x; + dy2 = arc[2].y - arc[0].y; + s = FT_ABS( dy * dx2 - dx * dy2 ); + + if ( s > s_limit ) + goto Split; + + /* If P1 or P2 is outside P0-P3, split the curve. */ + if ( dy * dy1 + dx * dx1 < 0 || + dy * dy2 + dx * dx2 < 0 || + dy * (arc[3].y - arc[1].y) + dx * (arc[3].x - arc[1].x) < 0 || + dy * (arc[3].y - arc[2].y) + dx * (arc[3].x - arc[2].x) < 0 ) + goto Split; + + /* No reason to split. */ + goto Draw; + } + + Split: + gray_split_cubic( arc ); + arc += 3; + continue; + + Draw: + gray_render_line( RAS_VAR_ arc[0].x, arc[0].y ); + + if ( arc == ras.bez_stack ) + return; + + arc -= 3; + } + } + + + static int + gray_move_to( const FT_Vector* to, + gray_PWorker worker ) + { + TPos x, y; + + + /* record current cell, if any */ + gray_record_cell( RAS_VAR ); + + /* start to a new position */ + x = UPSCALE( to->x ); + y = UPSCALE( to->y ); + + gray_start_cell( RAS_VAR_ TRUNC( x ), TRUNC( y ) ); + + worker->x = x; + worker->y = y; + return 0; + } + + + static int + gray_line_to( const FT_Vector* to, + gray_PWorker worker ) + { + gray_render_line( RAS_VAR_ UPSCALE( to->x ), UPSCALE( to->y ) ); + return 0; + } + + + static int + gray_conic_to( const FT_Vector* control, + const FT_Vector* to, + gray_PWorker worker ) + { + gray_render_conic( RAS_VAR_ control, to ); + return 0; + } + + + static int + gray_cubic_to( const FT_Vector* control1, + const FT_Vector* control2, + const FT_Vector* to, + gray_PWorker worker ) + { + gray_render_cubic( RAS_VAR_ control1, control2, to ); + return 0; + } + + + static void + gray_render_span( int y, + int count, + const FT_Span* spans, + gray_PWorker worker ) + { + unsigned char* p; + FT_Bitmap* map = &worker->target; + + + /* first of all, compute the scanline offset */ + p = (unsigned char*)map->buffer - y * map->pitch; + if ( map->pitch >= 0 ) + p += (unsigned)( ( map->rows - 1 ) * map->pitch ); + + for ( ; count > 0; count--, spans++ ) + { + unsigned char coverage = spans->coverage; + + + if ( coverage ) + { + /* For small-spans it is faster to do it by ourselves than + * calling `memset'. This is mainly due to the cost of the + * function call. + */ + if ( spans->len >= 8 ) + FT_MEM_SET( p + spans->x, (unsigned char)coverage, spans->len ); + else + { + unsigned char* q = p + spans->x; + + + switch ( spans->len ) + { + case 7: *q++ = (unsigned char)coverage; + case 6: *q++ = (unsigned char)coverage; + case 5: *q++ = (unsigned char)coverage; + case 4: *q++ = (unsigned char)coverage; + case 3: *q++ = (unsigned char)coverage; + case 2: *q++ = (unsigned char)coverage; + case 1: *q = (unsigned char)coverage; + default: + ; + } + } + } + } + } + + + static void + gray_hline( RAS_ARG_ TCoord x, + TCoord y, + TPos area, + TCoord acount ) + { + FT_Span* span; + int count; + int coverage; + + + /* compute the coverage line's coverage, depending on the */ + /* outline fill rule */ + /* */ + /* the coverage percentage is area/(PIXEL_BITS*PIXEL_BITS*2) */ + /* */ + coverage = (int)( area >> ( PIXEL_BITS * 2 + 1 - 8 ) ); + /* use range 0..256 */ + if ( coverage < 0 ) + coverage = -coverage; + + if ( ras.outline.flags & FT_OUTLINE_EVEN_ODD_FILL ) + { + coverage &= 511; + + if ( coverage > 256 ) + coverage = 512 - coverage; + else if ( coverage == 256 ) + coverage = 255; + } + else + { + /* normal non-zero winding rule */ + if ( coverage >= 256 ) + coverage = 255; + } + + y += (TCoord)ras.min_ey; + x += (TCoord)ras.min_ex; + + /* FT_Span.x is a 16-bit short, so limit our coordinates appropriately */ + if ( x >= 32767 ) + x = 32767; + + /* FT_Span.y is an integer, so limit our coordinates appropriately */ + if ( y >= FT_INT_MAX ) + y = FT_INT_MAX; + + if ( coverage ) + { + /* see whether we can add this span to the current list */ + count = ras.num_gray_spans; + span = ras.gray_spans + count - 1; + if ( count > 0 && + ras.span_y == y && + (int)span->x + span->len == (int)x && + span->coverage == coverage ) + { + span->len = (unsigned short)( span->len + acount ); + return; + } + + if ( ras.span_y != y || count >= FT_MAX_GRAY_SPANS ) + { + if ( ras.render_span && count > 0 ) + ras.render_span( ras.span_y, count, ras.gray_spans, + ras.render_span_data ); + +#ifdef FT_DEBUG_LEVEL_TRACE + + if ( count > 0 ) + { + int n; + + + FT_TRACE7(( "y = %3d ", ras.span_y )); + span = ras.gray_spans; + for ( n = 0; n < count; n++, span++ ) + FT_TRACE7(( "[%d..%d]:%02x ", + span->x, span->x + span->len - 1, span->coverage )); + FT_TRACE7(( "\n" )); + } + +#endif /* FT_DEBUG_LEVEL_TRACE */ + + ras.num_gray_spans = 0; + ras.span_y = (int)y; + + count = 0; + span = ras.gray_spans; + } + else + span++; + + /* add a gray span to the current list */ + span->x = (short)x; + span->len = (unsigned short)acount; + span->coverage = (unsigned char)coverage; + + ras.num_gray_spans++; + } + } + + +#ifdef FT_DEBUG_LEVEL_TRACE + + /* to be called while in the debugger -- */ + /* this function causes a compiler warning since it is unused otherwise */ + static void + gray_dump_cells( RAS_ARG ) + { + int yindex; + + + for ( yindex = 0; yindex < ras.ycount; yindex++ ) + { + PCell cell; + + + printf( "%3d:", yindex ); + + for ( cell = ras.ycells[yindex]; cell != NULL; cell = cell->next ) + printf( " (%3ld, c:%4ld, a:%6d)", cell->x, cell->cover, cell->area ); + printf( "\n" ); + } + } + +#endif /* FT_DEBUG_LEVEL_TRACE */ + + + static void + gray_sweep( RAS_ARG_ const FT_Bitmap* target ) + { + int yindex; + + FT_UNUSED( target ); + + + if ( ras.num_cells == 0 ) + return; + + ras.num_gray_spans = 0; + + FT_TRACE7(( "gray_sweep: start\n" )); + + for ( yindex = 0; yindex < ras.ycount; yindex++ ) + { + PCell cell = ras.ycells[yindex]; + TCoord cover = 0; + TCoord x = 0; + + + for ( ; cell != NULL; cell = cell->next ) + { + TPos area; + + + if ( cell->x > x && cover != 0 ) + gray_hline( RAS_VAR_ x, yindex, cover * ( ONE_PIXEL * 2 ), + cell->x - x ); + + cover += cell->cover; + area = cover * ( ONE_PIXEL * 2 ) - cell->area; + + if ( area != 0 && cell->x >= 0 ) + gray_hline( RAS_VAR_ cell->x, yindex, area, 1 ); + + x = cell->x + 1; + } + + if ( cover != 0 ) + gray_hline( RAS_VAR_ x, yindex, cover * ( ONE_PIXEL * 2 ), + ras.count_ex - x ); + } + + if ( ras.render_span && ras.num_gray_spans > 0 ) + ras.render_span( ras.span_y, ras.num_gray_spans, + ras.gray_spans, ras.render_span_data ); + + FT_TRACE7(( "gray_sweep: end\n" )); + } + + +#ifdef _STANDALONE_ + + /*************************************************************************/ + /* */ + /* The following function should only compile in stand-alone mode, */ + /* i.e., when building this component without the rest of FreeType. */ + /* */ + /*************************************************************************/ + + /*************************************************************************/ + /* */ + /* <Function> */ + /* FT_Outline_Decompose */ + /* */ + /* <Description> */ + /* Walk over an outline's structure to decompose it into individual */ + /* segments and Bézier arcs. This function is also able to emit */ + /* `move to' and `close to' operations to indicate the start and end */ + /* of new contours in the outline. */ + /* */ + /* <Input> */ + /* outline :: A pointer to the source target. */ + /* */ + /* func_interface :: A table of `emitters', i.e., function pointers */ + /* called during decomposition to indicate path */ + /* operations. */ + /* */ + /* <InOut> */ + /* user :: A typeless pointer which is passed to each */ + /* emitter during the decomposition. It can be */ + /* used to store the state during the */ + /* decomposition. */ + /* */ + /* <Return> */ + /* Error code. 0 means success. */ + /* */ + static int + FT_Outline_Decompose( const FT_Outline* outline, + const FT_Outline_Funcs* func_interface, + void* user ) + { +#undef SCALED +#define SCALED( x ) ( ( (x) << shift ) - delta ) + + FT_Vector v_last; + FT_Vector v_control; + FT_Vector v_start; + + FT_Vector* point; + FT_Vector* limit; + char* tags; + + int error; + + int n; /* index of contour in outline */ + int first; /* index of first point in contour */ + char tag; /* current point's state */ + + int shift; + TPos delta; + + + if ( !outline || !func_interface ) + return ErrRaster_Invalid_Argument; + + shift = func_interface->shift; + delta = func_interface->delta; + first = 0; + + for ( n = 0; n < outline->n_contours; n++ ) + { + int last; /* index of last point in contour */ + + + FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n )); + + last = outline->contours[n]; + if ( last < 0 ) + goto Invalid_Outline; + limit = outline->points + last; + + v_start = outline->points[first]; + v_start.x = SCALED( v_start.x ); + v_start.y = SCALED( v_start.y ); + + v_last = outline->points[last]; + v_last.x = SCALED( v_last.x ); + v_last.y = SCALED( v_last.y ); + + v_control = v_start; + + point = outline->points + first; + tags = outline->tags + first; + tag = FT_CURVE_TAG( tags[0] ); + + /* A contour cannot start with a cubic control point! */ + if ( tag == FT_CURVE_TAG_CUBIC ) + goto Invalid_Outline; + + /* check first point to determine origin */ + if ( tag == FT_CURVE_TAG_CONIC ) + { + /* first point is conic control. Yes, this happens. */ + if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON ) + { + /* start at last point if it is on the curve */ + v_start = v_last; + limit--; + } + else + { + /* if both first and last points are conic, */ + /* start at their middle and record its position */ + /* for closure */ + v_start.x = ( v_start.x + v_last.x ) / 2; + v_start.y = ( v_start.y + v_last.y ) / 2; + + v_last = v_start; + } + point--; + tags--; + } + + FT_TRACE5(( " move to (%.2f, %.2f)\n", + v_start.x / 64.0, v_start.y / 64.0 )); + error = func_interface->move_to( &v_start, user ); + if ( error ) + goto Exit; + + while ( point < limit ) + { + point++; + tags++; + + tag = FT_CURVE_TAG( tags[0] ); + switch ( tag ) + { + case FT_CURVE_TAG_ON: /* emit a single line_to */ + { + FT_Vector vec; + + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + FT_TRACE5(( " line to (%.2f, %.2f)\n", + vec.x / 64.0, vec.y / 64.0 )); + error = func_interface->line_to( &vec, user ); + if ( error ) + goto Exit; + continue; + } + + case FT_CURVE_TAG_CONIC: /* consume conic arcs */ + v_control.x = SCALED( point->x ); + v_control.y = SCALED( point->y ); + + Do_Conic: + if ( point < limit ) + { + FT_Vector vec; + FT_Vector v_middle; + + + point++; + tags++; + tag = FT_CURVE_TAG( tags[0] ); + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + if ( tag == FT_CURVE_TAG_ON ) + { + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + vec.x / 64.0, vec.y / 64.0, + v_control.x / 64.0, v_control.y / 64.0 )); + error = func_interface->conic_to( &v_control, &vec, user ); + if ( error ) + goto Exit; + continue; + } + + if ( tag != FT_CURVE_TAG_CONIC ) + goto Invalid_Outline; + + v_middle.x = ( v_control.x + vec.x ) / 2; + v_middle.y = ( v_control.y + vec.y ) / 2; + + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + v_middle.x / 64.0, v_middle.y / 64.0, + v_control.x / 64.0, v_control.y / 64.0 )); + error = func_interface->conic_to( &v_control, &v_middle, user ); + if ( error ) + goto Exit; + + v_control = vec; + goto Do_Conic; + } + + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + v_start.x / 64.0, v_start.y / 64.0, + v_control.x / 64.0, v_control.y / 64.0 )); + error = func_interface->conic_to( &v_control, &v_start, user ); + goto Close; + + default: /* FT_CURVE_TAG_CUBIC */ + { + FT_Vector vec1, vec2; + + + if ( point + 1 > limit || + FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC ) + goto Invalid_Outline; + + point += 2; + tags += 2; + + vec1.x = SCALED( point[-2].x ); + vec1.y = SCALED( point[-2].y ); + + vec2.x = SCALED( point[-1].x ); + vec2.y = SCALED( point[-1].y ); + + if ( point <= limit ) + { + FT_Vector vec; + + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + FT_TRACE5(( " cubic to (%.2f, %.2f)" + " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", + vec.x / 64.0, vec.y / 64.0, + vec1.x / 64.0, vec1.y / 64.0, + vec2.x / 64.0, vec2.y / 64.0 )); + error = func_interface->cubic_to( &vec1, &vec2, &vec, user ); + if ( error ) + goto Exit; + continue; + } + + FT_TRACE5(( " cubic to (%.2f, %.2f)" + " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", + v_start.x / 64.0, v_start.y / 64.0, + vec1.x / 64.0, vec1.y / 64.0, + vec2.x / 64.0, vec2.y / 64.0 )); + error = func_interface->cubic_to( &vec1, &vec2, &v_start, user ); + goto Close; + } + } + } + + /* close the contour with a line segment */ + FT_TRACE5(( " line to (%.2f, %.2f)\n", + v_start.x / 64.0, v_start.y / 64.0 )); + error = func_interface->line_to( &v_start, user ); + + Close: + if ( error ) + goto Exit; + + first = last + 1; + } + + FT_TRACE5(( "FT_Outline_Decompose: Done\n", n )); + return 0; + + Exit: + FT_TRACE5(( "FT_Outline_Decompose: Error %d\n", error )); + return error; + + Invalid_Outline: + return ErrRaster_Invalid_Outline; + } + +#endif /* _STANDALONE_ */ + + + typedef struct gray_TBand_ + { + TPos min, max; + + } gray_TBand; + + FT_DEFINE_OUTLINE_FUNCS(func_interface, + (FT_Outline_MoveTo_Func) gray_move_to, + (FT_Outline_LineTo_Func) gray_line_to, + (FT_Outline_ConicTo_Func)gray_conic_to, + (FT_Outline_CubicTo_Func)gray_cubic_to, + 0, + 0 + ) + + static int + gray_convert_glyph_inner( RAS_ARG ) + { + + volatile int error = 0; + +#ifdef FT_CONFIG_OPTION_PIC + FT_Outline_Funcs func_interface; + Init_Class_func_interface(&func_interface); +#endif + + if ( ft_setjmp( ras.jump_buffer ) == 0 ) + { + error = FT_Outline_Decompose( &ras.outline, &func_interface, &ras ); + gray_record_cell( RAS_VAR ); + } + else + error = ErrRaster_Memory_Overflow; + + return error; + } + + + static int + gray_convert_glyph( RAS_ARG ) + { + gray_TBand bands[40]; + gray_TBand* volatile band; + int volatile n, num_bands; + TPos volatile min, max, max_y; + FT_BBox* clip; + + + /* Set up state in the raster object */ + gray_compute_cbox( RAS_VAR ); + + /* clip to target bitmap, exit if nothing to do */ + clip = &ras.clip_box; + + if ( ras.max_ex <= clip->xMin || ras.min_ex >= clip->xMax || + ras.max_ey <= clip->yMin || ras.min_ey >= clip->yMax ) + return 0; + + if ( ras.min_ex < clip->xMin ) ras.min_ex = clip->xMin; + if ( ras.min_ey < clip->yMin ) ras.min_ey = clip->yMin; + + if ( ras.max_ex > clip->xMax ) ras.max_ex = clip->xMax; + if ( ras.max_ey > clip->yMax ) ras.max_ey = clip->yMax; + + ras.count_ex = ras.max_ex - ras.min_ex; + ras.count_ey = ras.max_ey - ras.min_ey; + + /* set up vertical bands */ + num_bands = (int)( ( ras.max_ey - ras.min_ey ) / ras.band_size ); + if ( num_bands == 0 ) + num_bands = 1; + if ( num_bands >= 39 ) + num_bands = 39; + + ras.band_shoot = 0; + + min = ras.min_ey; + max_y = ras.max_ey; + + for ( n = 0; n < num_bands; n++, min = max ) + { + max = min + ras.band_size; + if ( n == num_bands - 1 || max > max_y ) + max = max_y; + + bands[0].min = min; + bands[0].max = max; + band = bands; + + while ( band >= bands ) + { + TPos bottom, top, middle; + int error; + + { + PCell cells_max; + int yindex; + long cell_start, cell_end, cell_mod; + + + ras.ycells = (PCell*)ras.buffer; + ras.ycount = band->max - band->min; + + cell_start = sizeof ( PCell ) * ras.ycount; + cell_mod = cell_start % sizeof ( TCell ); + if ( cell_mod > 0 ) + cell_start += sizeof ( TCell ) - cell_mod; + + cell_end = ras.buffer_size; + cell_end -= cell_end % sizeof ( TCell ); + + cells_max = (PCell)( (char*)ras.buffer + cell_end ); + ras.cells = (PCell)( (char*)ras.buffer + cell_start ); + if ( ras.cells >= cells_max ) + goto ReduceBands; + + ras.max_cells = cells_max - ras.cells; + if ( ras.max_cells < 2 ) + goto ReduceBands; + + for ( yindex = 0; yindex < ras.ycount; yindex++ ) + ras.ycells[yindex] = NULL; + } + + ras.num_cells = 0; + ras.invalid = 1; + ras.min_ey = band->min; + ras.max_ey = band->max; + ras.count_ey = band->max - band->min; + + error = gray_convert_glyph_inner( RAS_VAR ); + + if ( !error ) + { + gray_sweep( RAS_VAR_ &ras.target ); + band--; + continue; + } + else if ( error != ErrRaster_Memory_Overflow ) + return 1; + + ReduceBands: + /* render pool overflow; we will reduce the render band by half */ + bottom = band->min; + top = band->max; + middle = bottom + ( ( top - bottom ) >> 1 ); + + /* This is too complex for a single scanline; there must */ + /* be some problems. */ + if ( middle == bottom ) + { +#ifdef FT_DEBUG_LEVEL_TRACE + FT_TRACE7(( "gray_convert_glyph: rotten glyph\n" )); +#endif + return 1; + } + + if ( bottom-top >= ras.band_size ) + ras.band_shoot++; + + band[1].min = bottom; + band[1].max = middle; + band[0].min = middle; + band[0].max = top; + band++; + } + } + + if ( ras.band_shoot > 8 && ras.band_size > 16 ) + ras.band_size = ras.band_size / 2; + + return 0; + } + + + static int + gray_raster_render( gray_PRaster raster, + const FT_Raster_Params* params ) + { + const FT_Outline* outline = (const FT_Outline*)params->source; + const FT_Bitmap* target_map = params->target; + gray_PWorker worker; + + + if ( !raster || !raster->buffer || !raster->buffer_size ) + return ErrRaster_Invalid_Argument; + + if ( !outline ) + return ErrRaster_Invalid_Outline; + + /* return immediately if the outline is empty */ + if ( outline->n_points == 0 || outline->n_contours <= 0 ) + return 0; + + if ( !outline->contours || !outline->points ) + return ErrRaster_Invalid_Outline; + + if ( outline->n_points != + outline->contours[outline->n_contours - 1] + 1 ) + return ErrRaster_Invalid_Outline; + + worker = raster->worker; + + /* if direct mode is not set, we must have a target bitmap */ + if ( !( params->flags & FT_RASTER_FLAG_DIRECT ) ) + { + if ( !target_map ) + return ErrRaster_Invalid_Argument; + + /* nothing to do */ + if ( !target_map->width || !target_map->rows ) + return 0; + + if ( !target_map->buffer ) + return ErrRaster_Invalid_Argument; + } + + /* this version does not support monochrome rendering */ + if ( !( params->flags & FT_RASTER_FLAG_AA ) ) + return ErrRaster_Invalid_Mode; + + /* compute clipping box */ + if ( !( params->flags & FT_RASTER_FLAG_DIRECT ) ) + { + /* compute clip box from target pixmap */ + ras.clip_box.xMin = 0; + ras.clip_box.yMin = 0; + ras.clip_box.xMax = target_map->width; + ras.clip_box.yMax = target_map->rows; + } + else if ( params->flags & FT_RASTER_FLAG_CLIP ) + ras.clip_box = params->clip_box; + else + { + ras.clip_box.xMin = -32768L; + ras.clip_box.yMin = -32768L; + ras.clip_box.xMax = 32767L; + ras.clip_box.yMax = 32767L; + } + + gray_init_cells( RAS_VAR_ raster->buffer, raster->buffer_size ); + + ras.outline = *outline; + ras.num_cells = 0; + ras.invalid = 1; + ras.band_size = raster->band_size; + ras.num_gray_spans = 0; + + if ( params->flags & FT_RASTER_FLAG_DIRECT ) + { + ras.render_span = (FT_Raster_Span_Func)params->gray_spans; + ras.render_span_data = params->user; + } + else + { + ras.target = *target_map; + ras.render_span = (FT_Raster_Span_Func)gray_render_span; + ras.render_span_data = &ras; + } + + return gray_convert_glyph( RAS_VAR ); + } + + + /**** RASTER OBJECT CREATION: In stand-alone mode, we simply use *****/ + /**** a static object. *****/ + +#ifdef _STANDALONE_ + + static int + gray_raster_new( void* memory, + FT_Raster* araster ) + { + static gray_TRaster the_raster; + + FT_UNUSED( memory ); + + + *araster = (FT_Raster)&the_raster; + FT_MEM_ZERO( &the_raster, sizeof ( the_raster ) ); + + return 0; + } + + + static void + gray_raster_done( FT_Raster raster ) + { + /* nothing */ + FT_UNUSED( raster ); + } + +#else /* !_STANDALONE_ */ + + static int + gray_raster_new( FT_Memory memory, + FT_Raster* araster ) + { + FT_Error error; + gray_PRaster raster = NULL; + + + *araster = 0; + if ( !FT_ALLOC( raster, sizeof ( gray_TRaster ) ) ) + { + raster->memory = memory; + *araster = (FT_Raster)raster; + } + + return error; + } + + + static void + gray_raster_done( FT_Raster raster ) + { + FT_Memory memory = (FT_Memory)((gray_PRaster)raster)->memory; + + + FT_FREE( raster ); + } + +#endif /* !_STANDALONE_ */ + + + static void + gray_raster_reset( FT_Raster raster, + char* pool_base, + long pool_size ) + { + gray_PRaster rast = (gray_PRaster)raster; + + + if ( raster ) + { + if ( pool_base && pool_size >= (long)sizeof ( gray_TWorker ) + 2048 ) + { + gray_PWorker worker = (gray_PWorker)pool_base; + + + rast->worker = worker; + rast->buffer = pool_base + + ( ( sizeof ( gray_TWorker ) + + sizeof ( TCell ) - 1 ) & + ~( sizeof ( TCell ) - 1 ) ); + rast->buffer_size = (long)( ( pool_base + pool_size ) - + (char*)rast->buffer ) & + ~( sizeof ( TCell ) - 1 ); + rast->band_size = (int)( rast->buffer_size / + ( sizeof ( TCell ) * 8 ) ); + } + else + { + rast->buffer = NULL; + rast->buffer_size = 0; + rast->worker = NULL; + } + } + } + + + FT_DEFINE_RASTER_FUNCS(ft_grays_raster, + FT_GLYPH_FORMAT_OUTLINE, + + (FT_Raster_New_Func) gray_raster_new, + (FT_Raster_Reset_Func) gray_raster_reset, + (FT_Raster_Set_Mode_Func)0, + (FT_Raster_Render_Func) gray_raster_render, + (FT_Raster_Done_Func) gray_raster_done + ) + + +/* END */ + + +/* Local Variables: */ +/* coding: utf-8 */ +/* End: */ |