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diff --git a/Build/source/libs/freetype2/freetype-2.6/src/autofit/aflatin.c b/Build/source/libs/freetype2/freetype-2.6/src/autofit/aflatin.c
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+++ b/Build/source/libs/freetype2/freetype-2.6/src/autofit/aflatin.c
@@ -0,0 +1,2916 @@
+/***************************************************************************/
+/* */
+/* aflatin.c */
+/* */
+/* Auto-fitter hinting routines for latin writing system (body). */
+/* */
+/* Copyright 2003-2015 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. */
+/* */
+/***************************************************************************/
+
+
+#include <ft2build.h>
+#include FT_ADVANCES_H
+#include FT_INTERNAL_DEBUG_H
+
+#include "afglobal.h"
+#include "afpic.h"
+#include "aflatin.h"
+#include "aferrors.h"
+
+
+#ifdef AF_CONFIG_OPTION_USE_WARPER
+#include "afwarp.h"
+#endif
+
+
+ /*************************************************************************/
+ /* */
+ /* 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_aflatin
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** L A T I N G L O B A L M E T R I C S *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ /* Find segments and links, compute all stem widths, and initialize */
+ /* standard width and height for the glyph with given charcode. */
+
+ FT_LOCAL_DEF( void )
+ af_latin_metrics_init_widths( AF_LatinMetrics metrics,
+ FT_Face face )
+ {
+ /* scan the array of segments in each direction */
+ AF_GlyphHintsRec hints[1];
+
+
+ FT_TRACE5(( "\n"
+ "latin standard widths computation (style `%s')\n"
+ "=====================================================\n"
+ "\n",
+ af_style_names[metrics->root.style_class->style] ));
+
+ af_glyph_hints_init( hints, face->memory );
+
+ metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
+ metrics->axis[AF_DIMENSION_VERT].width_count = 0;
+
+ {
+ FT_Error error;
+ FT_ULong glyph_index;
+ FT_Long y_offset;
+ int dim;
+ AF_LatinMetricsRec dummy[1];
+ AF_Scaler scaler = &dummy->root.scaler;
+
+#ifdef FT_CONFIG_OPTION_PIC
+ AF_FaceGlobals globals = metrics->root.globals;
+#endif
+
+ AF_StyleClass style_class = metrics->root.style_class;
+ AF_ScriptClass script_class = AF_SCRIPT_CLASSES_GET
+ [style_class->script];
+
+ FT_UInt32 standard_char;
+
+
+ /*
+ * We check more than a single standard character to catch features
+ * like `c2sc' (small caps from caps) that don't contain lowercase
+ * letters by definition, or other features that mainly operate on
+ * numerals.
+ */
+
+ standard_char = script_class->standard_char1;
+ af_get_char_index( &metrics->root,
+ standard_char,
+ &glyph_index,
+ &y_offset );
+ if ( !glyph_index )
+ {
+ if ( script_class->standard_char2 )
+ {
+ standard_char = script_class->standard_char2;
+ af_get_char_index( &metrics->root,
+ standard_char,
+ &glyph_index,
+ &y_offset );
+ if ( !glyph_index )
+ {
+ if ( script_class->standard_char3 )
+ {
+ standard_char = script_class->standard_char3;
+ af_get_char_index( &metrics->root,
+ standard_char,
+ &glyph_index,
+ &y_offset );
+ if ( !glyph_index )
+ goto Exit;
+ }
+ else
+ goto Exit;
+ }
+ }
+ else
+ goto Exit;
+ }
+
+ FT_TRACE5(( "standard character: U+%04lX (glyph index %d)\n",
+ standard_char, glyph_index ));
+
+ error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
+ if ( error || face->glyph->outline.n_points <= 0 )
+ goto Exit;
+
+ FT_ZERO( dummy );
+
+ dummy->units_per_em = metrics->units_per_em;
+
+ scaler->x_scale = 0x10000L;
+ scaler->y_scale = 0x10000L;
+ scaler->x_delta = 0;
+ scaler->y_delta = 0;
+
+ scaler->face = face;
+ scaler->render_mode = FT_RENDER_MODE_NORMAL;
+ scaler->flags = 0;
+
+ af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy );
+
+ error = af_glyph_hints_reload( hints, &face->glyph->outline );
+ if ( error )
+ goto Exit;
+
+ for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
+ {
+ AF_LatinAxis axis = &metrics->axis[dim];
+ AF_AxisHints axhints = &hints->axis[dim];
+ AF_Segment seg, limit, link;
+ FT_UInt num_widths = 0;
+
+
+ error = af_latin_hints_compute_segments( hints,
+ (AF_Dimension)dim );
+ if ( error )
+ goto Exit;
+
+ /*
+ * We assume that the glyphs selected for the stem width
+ * computation are `featureless' enough so that the linking
+ * algorithm works fine without adjustments of its scoring
+ * function.
+ */
+ af_latin_hints_link_segments( hints,
+ 0,
+ NULL,
+ (AF_Dimension)dim );
+
+ seg = axhints->segments;
+ limit = seg + axhints->num_segments;
+
+ for ( ; seg < limit; seg++ )
+ {
+ link = seg->link;
+
+ /* we only consider stem segments there! */
+ if ( link && link->link == seg && link > seg )
+ {
+ FT_Pos dist;
+
+
+ dist = seg->pos - link->pos;
+ if ( dist < 0 )
+ dist = -dist;
+
+ if ( num_widths < AF_LATIN_MAX_WIDTHS )
+ axis->widths[num_widths++].org = dist;
+ }
+ }
+
+ /* this also replaces multiple almost identical stem widths */
+ /* with a single one (the value 100 is heuristic) */
+ af_sort_and_quantize_widths( &num_widths, axis->widths,
+ dummy->units_per_em / 100 );
+ axis->width_count = num_widths;
+ }
+
+ Exit:
+ for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
+ {
+ AF_LatinAxis axis = &metrics->axis[dim];
+ FT_Pos stdw;
+
+
+ stdw = ( axis->width_count > 0 ) ? axis->widths[0].org
+ : AF_LATIN_CONSTANT( metrics, 50 );
+
+ /* let's try 20% of the smallest width */
+ axis->edge_distance_threshold = stdw / 5;
+ axis->standard_width = stdw;
+ axis->extra_light = 0;
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ {
+ FT_UInt i;
+
+
+ FT_TRACE5(( "%s widths:\n",
+ dim == AF_DIMENSION_VERT ? "horizontal"
+ : "vertical" ));
+
+ FT_TRACE5(( " %d (standard)", axis->standard_width ));
+ for ( i = 1; i < axis->width_count; i++ )
+ FT_TRACE5(( " %d", axis->widths[i].org ));
+
+ FT_TRACE5(( "\n" ));
+ }
+#endif
+ }
+ }
+
+ FT_TRACE5(( "\n" ));
+
+ af_glyph_hints_done( hints );
+ }
+
+
+ /* Find all blue zones. Flat segments give the reference points, */
+ /* round segments the overshoot positions. */
+
+ static void
+ af_latin_metrics_init_blues( AF_LatinMetrics metrics,
+ FT_Face face )
+ {
+ FT_Pos flats [AF_BLUE_STRING_MAX_LEN];
+ FT_Pos rounds[AF_BLUE_STRING_MAX_LEN];
+
+ FT_UInt num_flats;
+ FT_UInt num_rounds;
+
+ AF_LatinBlue blue;
+ FT_Error error;
+ AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT];
+ FT_Outline outline;
+
+ AF_StyleClass sc = metrics->root.style_class;
+
+ AF_Blue_Stringset bss = sc->blue_stringset;
+ const AF_Blue_StringRec* bs = &af_blue_stringsets[bss];
+
+
+ /* we walk over the blue character strings as specified in the */
+ /* style's entry in the `af_blue_stringset' array */
+
+ FT_TRACE5(( "latin blue zones computation\n"
+ "============================\n"
+ "\n" ));
+
+ for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ )
+ {
+ const char* p = &af_blue_strings[bs->string];
+ FT_Pos* blue_ref;
+ FT_Pos* blue_shoot;
+
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ {
+ FT_Bool have_flag = 0;
+
+
+ FT_TRACE5(( "blue zone %d", axis->blue_count ));
+
+ if ( bs->properties )
+ {
+ FT_TRACE5(( " (" ));
+
+ if ( AF_LATIN_IS_TOP_BLUE( bs ) )
+ {
+ FT_TRACE5(( "top" ));
+ have_flag = 1;
+ }
+
+ if ( AF_LATIN_IS_NEUTRAL_BLUE( bs ) )
+ {
+ if ( have_flag )
+ FT_TRACE5(( ", " ));
+ FT_TRACE5(( "neutral" ));
+ have_flag = 1;
+ }
+
+ if ( AF_LATIN_IS_X_HEIGHT_BLUE( bs ) )
+ {
+ if ( have_flag )
+ FT_TRACE5(( ", " ));
+ FT_TRACE5(( "small top" ));
+ have_flag = 1;
+ }
+
+ if ( AF_LATIN_IS_LONG_BLUE( bs ) )
+ {
+ if ( have_flag )
+ FT_TRACE5(( ", " ));
+ FT_TRACE5(( "long" ));
+ }
+
+ FT_TRACE5(( ")" ));
+ }
+
+ FT_TRACE5(( ":\n" ));
+ }
+#endif /* FT_DEBUG_LEVEL_TRACE */
+
+ num_flats = 0;
+ num_rounds = 0;
+
+ while ( *p )
+ {
+ FT_ULong ch;
+ FT_ULong glyph_index;
+ FT_Long y_offset;
+ FT_Pos best_y; /* same as points.y */
+ FT_Int best_point, best_contour_first, best_contour_last;
+ FT_Vector* points;
+ FT_Bool round = 0;
+
+
+ GET_UTF8_CHAR( ch, p );
+
+ /* load the character in the face -- skip unknown or empty ones */
+ af_get_char_index( &metrics->root, ch, &glyph_index, &y_offset );
+ if ( glyph_index == 0 )
+ {
+ FT_TRACE5(( " U+%04lX unavailable\n", ch ));
+ continue;
+ }
+
+ error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
+ outline = face->glyph->outline;
+ /* reject glyphs that don't produce any rendering */
+ if ( error || outline.n_points <= 2 )
+ {
+ FT_TRACE5(( " U+%04lX contains no (usable) outlines\n", ch ));
+ continue;
+ }
+
+ /* now compute min or max point indices and coordinates */
+ points = outline.points;
+ best_point = -1;
+ best_y = 0; /* make compiler happy */
+ best_contour_first = 0; /* ditto */
+ best_contour_last = 0; /* ditto */
+
+ {
+ FT_Int nn;
+ FT_Int first = 0;
+ FT_Int last = -1;
+
+
+ for ( nn = 0; nn < outline.n_contours; first = last + 1, nn++ )
+ {
+ FT_Int old_best_point = best_point;
+ FT_Int pp;
+
+
+ last = outline.contours[nn];
+
+ /* Avoid single-point contours since they are never rasterized. */
+ /* In some fonts, they correspond to mark attachment points */
+ /* that are way outside of the glyph's real outline. */
+ if ( last <= first )
+ continue;
+
+ if ( AF_LATIN_IS_TOP_BLUE( bs ) )
+ {
+ for ( pp = first; pp <= last; pp++ )
+ if ( best_point < 0 || points[pp].y > best_y )
+ {
+ best_point = pp;
+ best_y = points[pp].y;
+ }
+ }
+ else
+ {
+ for ( pp = first; pp <= last; pp++ )
+ if ( best_point < 0 || points[pp].y < best_y )
+ {
+ best_point = pp;
+ best_y = points[pp].y;
+ }
+ }
+
+ if ( best_point != old_best_point )
+ {
+ best_contour_first = first;
+ best_contour_last = last;
+ }
+ }
+ }
+
+ /* now check whether the point belongs to a straight or round */
+ /* segment; we first need to find in which contour the extremum */
+ /* lies, then inspect its previous and next points */
+ if ( best_point >= 0 )
+ {
+ FT_Pos best_x = points[best_point].x;
+ FT_Int prev, next;
+ FT_Int best_segment_first, best_segment_last;
+ FT_Int best_on_point_first, best_on_point_last;
+ FT_Pos dist;
+
+
+ best_segment_first = best_point;
+ best_segment_last = best_point;
+
+ if ( FT_CURVE_TAG( outline.tags[best_point] ) == FT_CURVE_TAG_ON )
+ {
+ best_on_point_first = best_point;
+ best_on_point_last = best_point;
+ }
+ else
+ {
+ best_on_point_first = -1;
+ best_on_point_last = -1;
+ }
+
+ /* look for the previous and next points on the contour */
+ /* that are not on the same Y coordinate, then threshold */
+ /* the `closeness'... */
+ prev = best_point;
+ next = prev;
+
+ do
+ {
+ if ( prev > best_contour_first )
+ prev--;
+ else
+ prev = best_contour_last;
+
+ dist = FT_ABS( points[prev].y - best_y );
+ /* accept a small distance or a small angle (both values are */
+ /* heuristic; value 20 corresponds to approx. 2.9 degrees) */
+ if ( dist > 5 )
+ if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist )
+ break;
+
+ best_segment_first = prev;
+
+ if ( FT_CURVE_TAG( outline.tags[prev] ) == FT_CURVE_TAG_ON )
+ {
+ best_on_point_first = prev;
+ if ( best_on_point_last < 0 )
+ best_on_point_last = prev;
+ }
+
+ } while ( prev != best_point );
+
+ do
+ {
+ if ( next < best_contour_last )
+ next++;
+ else
+ next = best_contour_first;
+
+ dist = FT_ABS( points[next].y - best_y );
+ if ( dist > 5 )
+ if ( FT_ABS( points[next].x - best_x ) <= 20 * dist )
+ break;
+
+ best_segment_last = next;
+
+ if ( FT_CURVE_TAG( outline.tags[next] ) == FT_CURVE_TAG_ON )
+ {
+ best_on_point_last = next;
+ if ( best_on_point_first < 0 )
+ best_on_point_first = next;
+ }
+
+ } while ( next != best_point );
+
+ if ( AF_LATIN_IS_LONG_BLUE( bs ) )
+ {
+ /* If this flag is set, we have an additional constraint to */
+ /* get the blue zone distance: Find a segment of the topmost */
+ /* (or bottommost) contour that is longer than a heuristic */
+ /* threshold. This ensures that small bumps in the outline */
+ /* are ignored (for example, the `vertical serifs' found in */
+ /* many Hebrew glyph designs). */
+
+ /* If this segment is long enough, we are done. Otherwise, */
+ /* search the segment next to the extremum that is long */
+ /* enough, has the same direction, and a not too large */
+ /* vertical distance from the extremum. Note that the */
+ /* algorithm doesn't check whether the found segment is */
+ /* actually the one (vertically) nearest to the extremum. */
+
+ /* heuristic threshold value */
+ FT_Pos length_threshold = metrics->units_per_em / 25;
+
+
+ dist = FT_ABS( points[best_segment_last].x -
+ points[best_segment_first].x );
+
+ if ( dist < length_threshold &&
+ best_segment_last - best_segment_first + 2 <=
+ best_contour_last - best_contour_first )
+ {
+ /* heuristic threshold value */
+ FT_Pos height_threshold = metrics->units_per_em / 4;
+
+ FT_Int first;
+ FT_Int last;
+ FT_Bool hit;
+
+ /* we intentionally declare these two variables */
+ /* outside of the loop since various compilers emit */
+ /* incorrect warning messages otherwise, talking about */
+ /* `possibly uninitialized variables' */
+ FT_Int p_first = 0; /* make compiler happy */
+ FT_Int p_last = 0;
+
+ FT_Bool left2right;
+
+
+ /* compute direction */
+ prev = best_point;
+
+ do
+ {
+ if ( prev > best_contour_first )
+ prev--;
+ else
+ prev = best_contour_last;
+
+ if ( points[prev].x != best_x )
+ break;
+
+ } while ( prev != best_point );
+
+ /* skip glyph for the degenerate case */
+ if ( prev == best_point )
+ continue;
+
+ left2right = FT_BOOL( points[prev].x < points[best_point].x );
+
+ first = best_segment_last;
+ last = first;
+ hit = 0;
+
+ do
+ {
+ FT_Bool l2r;
+ FT_Pos d;
+
+
+ if ( !hit )
+ {
+ /* no hit; adjust first point */
+ first = last;
+
+ /* also adjust first and last on point */
+ if ( FT_CURVE_TAG( outline.tags[first] ) ==
+ FT_CURVE_TAG_ON )
+ {
+ p_first = first;
+ p_last = first;
+ }
+ else
+ {
+ p_first = -1;
+ p_last = -1;
+ }
+
+ hit = 1;
+ }
+
+ if ( last < best_contour_last )
+ last++;
+ else
+ last = best_contour_first;
+
+ if ( FT_ABS( best_y - points[first].y ) > height_threshold )
+ {
+ /* vertical distance too large */
+ hit = 0;
+ continue;
+ }
+
+ /* same test as above */
+ dist = FT_ABS( points[last].y - points[first].y );
+ if ( dist > 5 )
+ if ( FT_ABS( points[last].x - points[first].x ) <=
+ 20 * dist )
+ {
+ hit = 0;
+ continue;
+ }
+
+ if ( FT_CURVE_TAG( outline.tags[last] ) == FT_CURVE_TAG_ON )
+ {
+ p_last = last;
+ if ( p_first < 0 )
+ p_first = last;
+ }
+
+ l2r = FT_BOOL( points[first].x < points[last].x );
+ d = FT_ABS( points[last].x - points[first].x );
+
+ if ( l2r == left2right &&
+ d >= length_threshold )
+ {
+ /* all constraints are met; update segment after finding */
+ /* its end */
+ do
+ {
+ if ( last < best_contour_last )
+ last++;
+ else
+ last = best_contour_first;
+
+ d = FT_ABS( points[last].y - points[first].y );
+ if ( d > 5 )
+ if ( FT_ABS( points[next].x - points[first].x ) <=
+ 20 * dist )
+ {
+ if ( last > best_contour_first )
+ last--;
+ else
+ last = best_contour_last;
+ break;
+ }
+
+ p_last = last;
+
+ if ( FT_CURVE_TAG( outline.tags[last] ) ==
+ FT_CURVE_TAG_ON )
+ {
+ p_last = last;
+ if ( p_first < 0 )
+ p_first = last;
+ }
+
+ } while ( last != best_segment_first );
+
+ best_y = points[first].y;
+
+ best_segment_first = first;
+ best_segment_last = last;
+
+ best_on_point_first = p_first;
+ best_on_point_last = p_last;
+
+ break;
+ }
+
+ } while ( last != best_segment_first );
+ }
+ }
+
+ /* for computing blue zones, we add the y offset as returned */
+ /* by the currently used OpenType feature -- for example, */
+ /* superscript glyphs might be identical to subscript glyphs */
+ /* with a vertical shift */
+ best_y += y_offset;
+
+ FT_TRACE5(( " U+%04lX: best_y = %5ld", ch, best_y ));
+
+ /* now set the `round' flag depending on the segment's kind: */
+ /* */
+ /* - if the horizontal distance between the first and last */
+ /* `on' point is larger than upem/8 (value 8 is heuristic) */
+ /* we have a flat segment */
+ /* - if either the first or the last point of the segment is */
+ /* an `off' point, the segment is round, otherwise it is */
+ /* flat */
+ if ( best_on_point_first >= 0 &&
+ best_on_point_last >= 0 &&
+ (FT_UInt)( FT_ABS( points[best_on_point_last].x -
+ points[best_on_point_first].x ) ) >
+ metrics->units_per_em / 8 )
+ round = 0;
+ else
+ round = FT_BOOL(
+ FT_CURVE_TAG( outline.tags[best_segment_first] ) !=
+ FT_CURVE_TAG_ON ||
+ FT_CURVE_TAG( outline.tags[best_segment_last] ) !=
+ FT_CURVE_TAG_ON );
+
+ if ( round && AF_LATIN_IS_NEUTRAL_BLUE( bs ) )
+ {
+ /* only use flat segments for a neutral blue zone */
+ FT_TRACE5(( " (round, skipped)\n" ));
+ continue;
+ }
+
+ FT_TRACE5(( " (%s)\n", round ? "round" : "flat" ));
+ }
+
+ if ( round )
+ rounds[num_rounds++] = best_y;
+ else
+ flats[num_flats++] = best_y;
+ }
+
+ if ( num_flats == 0 && num_rounds == 0 )
+ {
+ /*
+ * we couldn't find a single glyph to compute this blue zone,
+ * we will simply ignore it then
+ */
+ FT_TRACE5(( " empty\n" ));
+ continue;
+ }
+
+ /* we have computed the contents of the `rounds' and `flats' tables, */
+ /* now determine the reference and overshoot position of the blue -- */
+ /* we simply take the median value after a simple sort */
+ af_sort_pos( num_rounds, rounds );
+ af_sort_pos( num_flats, flats );
+
+ blue = &axis->blues[axis->blue_count];
+ blue_ref = &blue->ref.org;
+ blue_shoot = &blue->shoot.org;
+
+ axis->blue_count++;
+
+ if ( num_flats == 0 )
+ {
+ *blue_ref =
+ *blue_shoot = rounds[num_rounds / 2];
+ }
+ else if ( num_rounds == 0 )
+ {
+ *blue_ref =
+ *blue_shoot = flats[num_flats / 2];
+ }
+ else
+ {
+ *blue_ref = flats [num_flats / 2];
+ *blue_shoot = rounds[num_rounds / 2];
+ }
+
+ /* there are sometimes problems: if the overshoot position of top */
+ /* zones is under its reference position, or the opposite for bottom */
+ /* zones. We must thus check everything there and correct the errors */
+ if ( *blue_shoot != *blue_ref )
+ {
+ FT_Pos ref = *blue_ref;
+ FT_Pos shoot = *blue_shoot;
+ FT_Bool over_ref = FT_BOOL( shoot > ref );
+
+
+ if ( AF_LATIN_IS_TOP_BLUE( bs ) ^ over_ref )
+ {
+ *blue_ref =
+ *blue_shoot = ( shoot + ref ) / 2;
+
+ FT_TRACE5(( " [overshoot smaller than reference,"
+ " taking mean value]\n" ));
+ }
+ }
+
+ blue->flags = 0;
+ if ( AF_LATIN_IS_TOP_BLUE( bs ) )
+ blue->flags |= AF_LATIN_BLUE_TOP;
+ if ( AF_LATIN_IS_NEUTRAL_BLUE( bs ) )
+ blue->flags |= AF_LATIN_BLUE_NEUTRAL;
+
+ /*
+ * The following flag is used later to adjust the y and x scales
+ * in order to optimize the pixel grid alignment of the top of small
+ * letters.
+ */
+ if ( AF_LATIN_IS_X_HEIGHT_BLUE( bs ) )
+ blue->flags |= AF_LATIN_BLUE_ADJUSTMENT;
+
+ FT_TRACE5(( " -> reference = %ld\n"
+ " overshoot = %ld\n",
+ *blue_ref, *blue_shoot ));
+ }
+
+ FT_TRACE5(( "\n" ));
+
+ return;
+ }
+
+
+ /* Check whether all ASCII digits have the same advance width. */
+
+ FT_LOCAL_DEF( void )
+ af_latin_metrics_check_digits( AF_LatinMetrics metrics,
+ FT_Face face )
+ {
+ FT_UInt i;
+ FT_Bool started = 0, same_width = 1;
+ FT_Fixed advance, old_advance = 0;
+
+
+ /* digit `0' is 0x30 in all supported charmaps */
+ for ( i = 0x30; i <= 0x39; i++ )
+ {
+ FT_ULong glyph_index;
+ FT_Long y_offset;
+
+
+ af_get_char_index( &metrics->root, i, &glyph_index, &y_offset );
+ if ( glyph_index == 0 )
+ continue;
+
+ if ( FT_Get_Advance( face, glyph_index,
+ FT_LOAD_NO_SCALE |
+ FT_LOAD_NO_HINTING |
+ FT_LOAD_IGNORE_TRANSFORM,
+ &advance ) )
+ continue;
+
+ if ( started )
+ {
+ if ( advance != old_advance )
+ {
+ same_width = 0;
+ break;
+ }
+ }
+ else
+ {
+ old_advance = advance;
+ started = 1;
+ }
+ }
+
+ metrics->root.digits_have_same_width = same_width;
+ }
+
+
+ /* Initialize global metrics. */
+
+ FT_LOCAL_DEF( FT_Error )
+ af_latin_metrics_init( AF_LatinMetrics metrics,
+ FT_Face face )
+ {
+ FT_CharMap oldmap = face->charmap;
+
+
+ metrics->units_per_em = face->units_per_EM;
+
+ if ( !FT_Select_Charmap( face, FT_ENCODING_UNICODE ) )
+ {
+ af_latin_metrics_init_widths( metrics, face );
+ af_latin_metrics_init_blues( metrics, face );
+ af_latin_metrics_check_digits( metrics, face );
+ }
+
+ FT_Set_Charmap( face, oldmap );
+ return FT_Err_Ok;
+ }
+
+
+ /* Adjust scaling value, then scale and shift widths */
+ /* and blue zones (if applicable) for given dimension. */
+
+ static void
+ af_latin_metrics_scale_dim( AF_LatinMetrics metrics,
+ AF_Scaler scaler,
+ AF_Dimension dim )
+ {
+ FT_Fixed scale;
+ FT_Pos delta;
+ AF_LatinAxis axis;
+ FT_UInt nn;
+
+
+ if ( dim == AF_DIMENSION_HORZ )
+ {
+ scale = scaler->x_scale;
+ delta = scaler->x_delta;
+ }
+ else
+ {
+ scale = scaler->y_scale;
+ delta = scaler->y_delta;
+ }
+
+ axis = &metrics->axis[dim];
+
+ if ( axis->org_scale == scale && axis->org_delta == delta )
+ return;
+
+ axis->org_scale = scale;
+ axis->org_delta = delta;
+
+ /*
+ * correct X and Y scale to optimize the alignment of the top of small
+ * letters to the pixel grid
+ */
+ {
+ AF_LatinAxis Axis = &metrics->axis[AF_DIMENSION_VERT];
+ AF_LatinBlue blue = NULL;
+
+
+ for ( nn = 0; nn < Axis->blue_count; nn++ )
+ {
+ if ( Axis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT )
+ {
+ blue = &Axis->blues[nn];
+ break;
+ }
+ }
+
+ if ( blue )
+ {
+ FT_Pos scaled;
+ FT_Pos threshold;
+ FT_Pos fitted;
+ FT_UInt limit;
+ FT_UInt ppem;
+
+
+ scaled = FT_MulFix( blue->shoot.org, scaler->y_scale );
+ ppem = metrics->root.scaler.face->size->metrics.x_ppem;
+ limit = metrics->root.globals->increase_x_height;
+ threshold = 40;
+
+ /* if the `increase-x-height' property is active, */
+ /* we round up much more often */
+ if ( limit &&
+ ppem <= limit &&
+ ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN )
+ threshold = 52;
+
+ fitted = ( scaled + threshold ) & ~63;
+
+ if ( scaled != fitted )
+ {
+#if 0
+ if ( dim == AF_DIMENSION_HORZ )
+ {
+ if ( fitted < scaled )
+ scale -= scale / 50; /* scale *= 0.98 */
+ }
+ else
+#endif
+ if ( dim == AF_DIMENSION_VERT )
+ {
+ scale = FT_MulDiv( scale, fitted, scaled );
+
+ FT_TRACE5((
+ "af_latin_metrics_scale_dim:"
+ " x height alignment (style `%s'):\n"
+ " "
+ " vertical scaling changed from %.4f to %.4f (by %d%%)\n"
+ "\n",
+ af_style_names[metrics->root.style_class->style],
+ axis->org_scale / 65536.0,
+ scale / 65536.0,
+ ( fitted - scaled ) * 100 / scaled ));
+ }
+ }
+ }
+ }
+
+ axis->scale = scale;
+ axis->delta = delta;
+
+ if ( dim == AF_DIMENSION_HORZ )
+ {
+ metrics->root.scaler.x_scale = scale;
+ metrics->root.scaler.x_delta = delta;
+ }
+ else
+ {
+ metrics->root.scaler.y_scale = scale;
+ metrics->root.scaler.y_delta = delta;
+ }
+
+ FT_TRACE5(( "%s widths (style `%s')\n",
+ dim == AF_DIMENSION_HORZ ? "horizontal" : "vertical",
+ af_style_names[metrics->root.style_class->style] ));
+
+ /* scale the widths */
+ for ( nn = 0; nn < axis->width_count; nn++ )
+ {
+ AF_Width width = axis->widths + nn;
+
+
+ width->cur = FT_MulFix( width->org, scale );
+ width->fit = width->cur;
+
+ FT_TRACE5(( " %d scaled to %.2f\n",
+ width->org,
+ width->cur / 64.0 ));
+ }
+
+ FT_TRACE5(( "\n" ));
+
+ /* an extra-light axis corresponds to a standard width that is */
+ /* smaller than 5/8 pixels */
+ axis->extra_light =
+ (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( axis->extra_light )
+ FT_TRACE5(( "`%s' style is extra light (at current resolution)\n"
+ "\n",
+ af_style_names[metrics->root.style_class->style] ));
+#endif
+
+ if ( dim == AF_DIMENSION_VERT )
+ {
+ FT_TRACE5(( "blue zones (style `%s')\n",
+ af_style_names[metrics->root.style_class->style] ));
+
+ /* scale the blue zones */
+ for ( nn = 0; nn < axis->blue_count; nn++ )
+ {
+ AF_LatinBlue blue = &axis->blues[nn];
+ FT_Pos dist;
+
+
+ blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta;
+ blue->ref.fit = blue->ref.cur;
+ blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
+ blue->shoot.fit = blue->shoot.cur;
+ blue->flags &= ~AF_LATIN_BLUE_ACTIVE;
+
+ /* a blue zone is only active if it is less than 3/4 pixels tall */
+ dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
+ if ( dist <= 48 && dist >= -48 )
+ {
+#if 0
+ FT_Pos delta1;
+#endif
+ FT_Pos delta2;
+
+
+ /* use discrete values for blue zone widths */
+
+#if 0
+
+ /* generic, original code */
+ delta1 = blue->shoot.org - blue->ref.org;
+ delta2 = delta1;
+ if ( delta1 < 0 )
+ delta2 = -delta2;
+
+ delta2 = FT_MulFix( delta2, scale );
+
+ if ( delta2 < 32 )
+ delta2 = 0;
+ else if ( delta2 < 64 )
+ delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
+ else
+ delta2 = FT_PIX_ROUND( delta2 );
+
+ if ( delta1 < 0 )
+ delta2 = -delta2;
+
+ blue->ref.fit = FT_PIX_ROUND( blue->ref.cur );
+ blue->shoot.fit = blue->ref.fit + delta2;
+
+#else
+
+ /* simplified version due to abs(dist) <= 48 */
+ delta2 = dist;
+ if ( dist < 0 )
+ delta2 = -delta2;
+
+ if ( delta2 < 32 )
+ delta2 = 0;
+ else if ( delta2 < 48 )
+ delta2 = 32;
+ else
+ delta2 = 64;
+
+ if ( dist < 0 )
+ delta2 = -delta2;
+
+ blue->ref.fit = FT_PIX_ROUND( blue->ref.cur );
+ blue->shoot.fit = blue->ref.fit - delta2;
+
+#endif
+
+ blue->flags |= AF_LATIN_BLUE_ACTIVE;
+
+ FT_TRACE5(( " reference %d: %d scaled to %.2f%s\n"
+ " overshoot %d: %d scaled to %.2f%s\n",
+ nn,
+ blue->ref.org,
+ blue->ref.fit / 64.0,
+ blue->flags & AF_LATIN_BLUE_ACTIVE ? ""
+ : " (inactive)",
+ nn,
+ blue->shoot.org,
+ blue->shoot.fit / 64.0,
+ blue->flags & AF_LATIN_BLUE_ACTIVE ? ""
+ : " (inactive)" ));
+ }
+ }
+ }
+ }
+
+
+ /* Scale global values in both directions. */
+
+ FT_LOCAL_DEF( void )
+ af_latin_metrics_scale( AF_LatinMetrics metrics,
+ AF_Scaler scaler )
+ {
+ metrics->root.scaler.render_mode = scaler->render_mode;
+ metrics->root.scaler.face = scaler->face;
+ metrics->root.scaler.flags = scaler->flags;
+
+ af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
+ af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
+ }
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** L A T I N G L Y P H A N A L Y S I S *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ /* Walk over all contours and compute its segments. */
+
+ FT_LOCAL_DEF( FT_Error )
+ af_latin_hints_compute_segments( AF_GlyphHints hints,
+ AF_Dimension dim )
+ {
+ AF_AxisHints axis = &hints->axis[dim];
+ FT_Memory memory = hints->memory;
+ FT_Error error = FT_Err_Ok;
+ AF_Segment segment = NULL;
+ AF_SegmentRec seg0;
+ AF_Point* contour = hints->contours;
+ AF_Point* contour_limit = contour + hints->num_contours;
+ AF_Direction major_dir, segment_dir;
+
+
+ FT_ZERO( &seg0 );
+ seg0.score = 32000;
+ seg0.flags = AF_EDGE_NORMAL;
+
+ major_dir = (AF_Direction)FT_ABS( axis->major_dir );
+ segment_dir = major_dir;
+
+ axis->num_segments = 0;
+
+ /* set up (u,v) in each point */
+ if ( dim == AF_DIMENSION_HORZ )
+ {
+ AF_Point point = hints->points;
+ AF_Point limit = point + hints->num_points;
+
+
+ for ( ; point < limit; point++ )
+ {
+ point->u = point->fx;
+ point->v = point->fy;
+ }
+ }
+ else
+ {
+ AF_Point point = hints->points;
+ AF_Point limit = point + hints->num_points;
+
+
+ for ( ; point < limit; point++ )
+ {
+ point->u = point->fy;
+ point->v = point->fx;
+ }
+ }
+
+ /* do each contour separately */
+ for ( ; contour < contour_limit; contour++ )
+ {
+ AF_Point point = contour[0];
+ AF_Point last = point->prev;
+ int on_edge = 0;
+ FT_Pos min_pos = 32000; /* minimum segment pos != min_coord */
+ FT_Pos max_pos = -32000; /* maximum segment pos != max_coord */
+ FT_Bool passed;
+
+
+ if ( point == last ) /* skip singletons -- just in case */
+ continue;
+
+ if ( FT_ABS( last->out_dir ) == major_dir &&
+ FT_ABS( point->out_dir ) == major_dir )
+ {
+ /* we are already on an edge, try to locate its start */
+ last = point;
+
+ for (;;)
+ {
+ point = point->prev;
+ if ( FT_ABS( point->out_dir ) != major_dir )
+ {
+ point = point->next;
+ break;
+ }
+ if ( point == last )
+ break;
+ }
+ }
+
+ last = point;
+ passed = 0;
+
+ for (;;)
+ {
+ FT_Pos u, v;
+
+
+ if ( on_edge )
+ {
+ u = point->u;
+ if ( u < min_pos )
+ min_pos = u;
+ if ( u > max_pos )
+ max_pos = u;
+
+ if ( point->out_dir != segment_dir || point == last )
+ {
+ /* we are just leaving an edge; record a new segment! */
+ segment->last = point;
+ segment->pos = (FT_Short)( ( min_pos + max_pos ) >> 1 );
+
+ /* a segment is round if either its first or last point */
+ /* is a control point */
+ if ( ( segment->first->flags | point->flags ) &
+ AF_FLAG_CONTROL )
+ segment->flags |= AF_EDGE_ROUND;
+
+ /* compute segment size */
+ min_pos = max_pos = point->v;
+
+ v = segment->first->v;
+ if ( v < min_pos )
+ min_pos = v;
+ if ( v > max_pos )
+ max_pos = v;
+
+ segment->min_coord = (FT_Short)min_pos;
+ segment->max_coord = (FT_Short)max_pos;
+ segment->height = (FT_Short)( segment->max_coord -
+ segment->min_coord );
+
+ on_edge = 0;
+ segment = NULL;
+ /* fall through */
+ }
+ }
+
+ /* now exit if we are at the start/end point */
+ if ( point == last )
+ {
+ if ( passed )
+ break;
+ passed = 1;
+ }
+
+ if ( !on_edge && FT_ABS( point->out_dir ) == major_dir )
+ {
+ /* this is the start of a new segment! */
+ segment_dir = (AF_Direction)point->out_dir;
+
+ error = af_axis_hints_new_segment( axis, memory, &segment );
+ if ( error )
+ goto Exit;
+
+ /* clear all segment fields */
+ segment[0] = seg0;
+
+ segment->dir = (FT_Char)segment_dir;
+ min_pos = max_pos = point->u;
+ segment->first = point;
+ segment->last = point;
+
+ on_edge = 1;
+ }
+
+ point = point->next;
+ }
+
+ } /* contours */
+
+
+ /* now slightly increase the height of segments if this makes */
+ /* sense -- this is used to better detect and ignore serifs */
+ {
+ AF_Segment segments = axis->segments;
+ AF_Segment segments_end = segments + axis->num_segments;
+
+
+ for ( segment = segments; segment < segments_end; segment++ )
+ {
+ AF_Point first = segment->first;
+ AF_Point last = segment->last;
+ FT_Pos first_v = first->v;
+ FT_Pos last_v = last->v;
+
+
+ if ( first_v < last_v )
+ {
+ AF_Point p;
+
+
+ p = first->prev;
+ if ( p->v < first_v )
+ segment->height = (FT_Short)( segment->height +
+ ( ( first_v - p->v ) >> 1 ) );
+
+ p = last->next;
+ if ( p->v > last_v )
+ segment->height = (FT_Short)( segment->height +
+ ( ( p->v - last_v ) >> 1 ) );
+ }
+ else
+ {
+ AF_Point p;
+
+
+ p = first->prev;
+ if ( p->v > first_v )
+ segment->height = (FT_Short)( segment->height +
+ ( ( p->v - first_v ) >> 1 ) );
+
+ p = last->next;
+ if ( p->v < last_v )
+ segment->height = (FT_Short)( segment->height +
+ ( ( last_v - p->v ) >> 1 ) );
+ }
+ }
+ }
+
+ Exit:
+ return error;
+ }
+
+
+ /* Link segments to form stems and serifs. If `width_count' and */
+ /* `widths' are non-zero, use them to fine-tune the scoring function. */
+
+ FT_LOCAL_DEF( void )
+ af_latin_hints_link_segments( AF_GlyphHints hints,
+ FT_UInt width_count,
+ AF_WidthRec* widths,
+ AF_Dimension dim )
+ {
+ AF_AxisHints axis = &hints->axis[dim];
+ AF_Segment segments = axis->segments;
+ AF_Segment segment_limit = segments + axis->num_segments;
+ FT_Pos len_threshold, len_score, dist_score, max_width;
+ AF_Segment seg1, seg2;
+
+
+ if ( width_count )
+ max_width = widths[width_count - 1].org;
+ else
+ max_width = 0;
+
+ /* a heuristic value to set up a minimum value for overlapping */
+ len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
+ if ( len_threshold == 0 )
+ len_threshold = 1;
+
+ /* a heuristic value to weight lengths */
+ len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 );
+
+ /* a heuristic value to weight distances (no call to */
+ /* AF_LATIN_CONSTANT needed, since we work on multiples */
+ /* of the stem width) */
+ dist_score = 3000;
+
+ /* now compare each segment to the others */
+ for ( seg1 = segments; seg1 < segment_limit; seg1++ )
+ {
+ if ( seg1->dir != axis->major_dir )
+ continue;
+
+ /* search for stems having opposite directions, */
+ /* with seg1 to the `left' of seg2 */
+ for ( seg2 = segments; seg2 < segment_limit; seg2++ )
+ {
+ FT_Pos pos1 = seg1->pos;
+ FT_Pos pos2 = seg2->pos;
+
+
+ if ( seg1->dir + seg2->dir == 0 && pos2 > pos1 )
+ {
+ /* compute distance between the two segments */
+ FT_Pos min = seg1->min_coord;
+ FT_Pos max = seg1->max_coord;
+ FT_Pos len;
+
+
+ if ( min < seg2->min_coord )
+ min = seg2->min_coord;
+
+ if ( max > seg2->max_coord )
+ max = seg2->max_coord;
+
+ /* compute maximum coordinate difference of the two segments */
+ /* (this is, how much they overlap) */
+ len = max - min;
+ if ( len >= len_threshold )
+ {
+ /*
+ * The score is the sum of two demerits indicating the
+ * `badness' of a fit, measured along the segments' main axis
+ * and orthogonal to it, respectively.
+ *
+ * o The less overlapping along the main axis, the worse it
+ * is, causing a larger demerit.
+ *
+ * o The nearer the orthogonal distance to a stem width, the
+ * better it is, causing a smaller demerit. For simplicity,
+ * however, we only increase the demerit for values that
+ * exceed the largest stem width.
+ */
+
+ FT_Pos dist = pos2 - pos1;
+
+ FT_Pos dist_demerit, score;
+
+
+ if ( max_width )
+ {
+ /* distance demerits are based on multiples of `max_width'; */
+ /* we scale by 1024 for getting more precision */
+ FT_Pos delta = ( dist << 10 ) / max_width - ( 1 << 10 );
+
+
+ if ( delta > 10000 )
+ dist_demerit = 32000;
+ else if ( delta > 0 )
+ dist_demerit = delta * delta / dist_score;
+ else
+ dist_demerit = 0;
+ }
+ else
+ dist_demerit = dist; /* default if no widths available */
+
+ score = dist_demerit + len_score / len;
+
+ /* and we search for the smallest score */
+ if ( score < seg1->score )
+ {
+ seg1->score = score;
+ seg1->link = seg2;
+ }
+
+ if ( score < seg2->score )
+ {
+ seg2->score = score;
+ seg2->link = seg1;
+ }
+ }
+ }
+ }
+ }
+
+ /* now compute the `serif' segments, cf. explanations in `afhints.h' */
+ for ( seg1 = segments; seg1 < segment_limit; seg1++ )
+ {
+ seg2 = seg1->link;
+
+ if ( seg2 )
+ {
+ if ( seg2->link != seg1 )
+ {
+ seg1->link = 0;
+ seg1->serif = seg2->link;
+ }
+ }
+ }
+ }
+
+
+ /* Link segments to edges, using feature analysis for selection. */
+
+ FT_LOCAL_DEF( FT_Error )
+ af_latin_hints_compute_edges( AF_GlyphHints hints,
+ AF_Dimension dim )
+ {
+ AF_AxisHints axis = &hints->axis[dim];
+ FT_Error error = FT_Err_Ok;
+ FT_Memory memory = hints->memory;
+ AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim];
+
+ AF_Segment segments = axis->segments;
+ AF_Segment segment_limit = segments + axis->num_segments;
+ AF_Segment seg;
+
+#if 0
+ AF_Direction up_dir;
+#endif
+ FT_Fixed scale;
+ FT_Pos edge_distance_threshold;
+ FT_Pos segment_length_threshold;
+
+
+ axis->num_edges = 0;
+
+ scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
+ : hints->y_scale;
+
+#if 0
+ up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP
+ : AF_DIR_RIGHT;
+#endif
+
+ /*
+ * We ignore all segments that are less than 1 pixel in length
+ * to avoid many problems with serif fonts. We compute the
+ * corresponding threshold in font units.
+ */
+ if ( dim == AF_DIMENSION_HORZ )
+ segment_length_threshold = FT_DivFix( 64, hints->y_scale );
+ else
+ segment_length_threshold = 0;
+
+ /*********************************************************************/
+ /* */
+ /* We begin by generating a sorted table of edges for the current */
+ /* direction. To do so, we simply scan each segment and try to find */
+ /* an edge in our table that corresponds to its position. */
+ /* */
+ /* If no edge is found, we create and insert a new edge in the */
+ /* sorted table. Otherwise, we simply add the segment to the edge's */
+ /* list which gets processed in the second step to compute the */
+ /* edge's properties. */
+ /* */
+ /* Note that the table of edges is sorted along the segment/edge */
+ /* position. */
+ /* */
+ /*********************************************************************/
+
+ /* assure that edge distance threshold is at most 0.25px */
+ edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
+ scale );
+ if ( edge_distance_threshold > 64 / 4 )
+ edge_distance_threshold = 64 / 4;
+
+ edge_distance_threshold = FT_DivFix( edge_distance_threshold,
+ scale );
+
+ for ( seg = segments; seg < segment_limit; seg++ )
+ {
+ AF_Edge found = NULL;
+ FT_Int ee;
+
+
+ if ( seg->height < segment_length_threshold )
+ continue;
+
+ /* A special case for serif edges: If they are smaller than */
+ /* 1.5 pixels we ignore them. */
+ if ( seg->serif &&
+ 2 * seg->height < 3 * segment_length_threshold )
+ continue;
+
+ /* look for an edge corresponding to the segment */
+ for ( ee = 0; ee < axis->num_edges; ee++ )
+ {
+ AF_Edge edge = axis->edges + ee;
+ FT_Pos dist;
+
+
+ dist = seg->pos - edge->fpos;
+ if ( dist < 0 )
+ dist = -dist;
+
+ if ( dist < edge_distance_threshold && edge->dir == seg->dir )
+ {
+ found = edge;
+ break;
+ }
+ }
+
+ if ( !found )
+ {
+ AF_Edge edge;
+
+
+ /* insert a new edge in the list and */
+ /* sort according to the position */
+ error = af_axis_hints_new_edge( axis, seg->pos,
+ (AF_Direction)seg->dir,
+ memory, &edge );
+ if ( error )
+ goto Exit;
+
+ /* add the segment to the new edge's list */
+ FT_ZERO( edge );
+
+ edge->first = seg;
+ edge->last = seg;
+ edge->dir = seg->dir;
+ edge->fpos = seg->pos;
+ edge->opos = FT_MulFix( seg->pos, scale );
+ edge->pos = edge->opos;
+ seg->edge_next = seg;
+ }
+ else
+ {
+ /* if an edge was found, simply add the segment to the edge's */
+ /* list */
+ seg->edge_next = found->first;
+ found->last->edge_next = seg;
+ found->last = seg;
+ }
+ }
+
+
+ /******************************************************************/
+ /* */
+ /* Good, we now compute each edge's properties according to the */
+ /* segments found on its position. Basically, these are */
+ /* */
+ /* - the edge's main direction */
+ /* - stem edge, serif edge or both (which defaults to stem then) */
+ /* - rounded edge, straight or both (which defaults to straight) */
+ /* - link for edge */
+ /* */
+ /******************************************************************/
+
+ /* first of all, set the `edge' field in each segment -- this is */
+ /* required in order to compute edge links */
+
+ /*
+ * Note that removing this loop and setting the `edge' field of each
+ * segment directly in the code above slows down execution speed for
+ * some reasons on platforms like the Sun.
+ */
+ {
+ AF_Edge edges = axis->edges;
+ AF_Edge edge_limit = edges + axis->num_edges;
+ AF_Edge edge;
+
+
+ for ( edge = edges; edge < edge_limit; edge++ )
+ {
+ seg = edge->first;
+ if ( seg )
+ do
+ {
+ seg->edge = edge;
+ seg = seg->edge_next;
+
+ } while ( seg != edge->first );
+ }
+
+ /* now compute each edge properties */
+ for ( edge = edges; edge < edge_limit; edge++ )
+ {
+ FT_Int is_round = 0; /* does it contain round segments? */
+ FT_Int is_straight = 0; /* does it contain straight segments? */
+#if 0
+ FT_Pos ups = 0; /* number of upwards segments */
+ FT_Pos downs = 0; /* number of downwards segments */
+#endif
+
+
+ seg = edge->first;
+
+ do
+ {
+ FT_Bool is_serif;
+
+
+ /* check for roundness of segment */
+ if ( seg->flags & AF_EDGE_ROUND )
+ is_round++;
+ else
+ is_straight++;
+
+#if 0
+ /* check for segment direction */
+ if ( seg->dir == up_dir )
+ ups += seg->max_coord - seg->min_coord;
+ else
+ downs += seg->max_coord - seg->min_coord;
+#endif
+
+ /* check for links -- if seg->serif is set, then seg->link must */
+ /* be ignored */
+ is_serif = (FT_Bool)( seg->serif &&
+ seg->serif->edge &&
+ seg->serif->edge != edge );
+
+ if ( ( seg->link && seg->link->edge != NULL ) || is_serif )
+ {
+ AF_Edge edge2;
+ AF_Segment seg2;
+
+
+ edge2 = edge->link;
+ seg2 = seg->link;
+
+ if ( is_serif )
+ {
+ seg2 = seg->serif;
+ edge2 = edge->serif;
+ }
+
+ if ( edge2 )
+ {
+ FT_Pos edge_delta;
+ FT_Pos seg_delta;
+
+
+ edge_delta = edge->fpos - edge2->fpos;
+ if ( edge_delta < 0 )
+ edge_delta = -edge_delta;
+
+ seg_delta = seg->pos - seg2->pos;
+ if ( seg_delta < 0 )
+ seg_delta = -seg_delta;
+
+ if ( seg_delta < edge_delta )
+ edge2 = seg2->edge;
+ }
+ else
+ edge2 = seg2->edge;
+
+ if ( is_serif )
+ {
+ edge->serif = edge2;
+ edge2->flags |= AF_EDGE_SERIF;
+ }
+ else
+ edge->link = edge2;
+ }
+
+ seg = seg->edge_next;
+
+ } while ( seg != edge->first );
+
+ /* set the round/straight flags */
+ edge->flags = AF_EDGE_NORMAL;
+
+ if ( is_round > 0 && is_round >= is_straight )
+ edge->flags |= AF_EDGE_ROUND;
+
+#if 0
+ /* set the edge's main direction */
+ edge->dir = AF_DIR_NONE;
+
+ if ( ups > downs )
+ edge->dir = (FT_Char)up_dir;
+
+ else if ( ups < downs )
+ edge->dir = (FT_Char)-up_dir;
+
+ else if ( ups == downs )
+ edge->dir = 0; /* both up and down! */
+#endif
+
+ /* get rid of serifs if link is set */
+ /* XXX: This gets rid of many unpleasant artefacts! */
+ /* Example: the `c' in cour.pfa at size 13 */
+
+ if ( edge->serif && edge->link )
+ edge->serif = NULL;
+ }
+ }
+
+ Exit:
+ return error;
+ }
+
+
+ /* Detect segments and edges for given dimension. */
+
+ FT_LOCAL_DEF( FT_Error )
+ af_latin_hints_detect_features( AF_GlyphHints hints,
+ FT_UInt width_count,
+ AF_WidthRec* widths,
+ AF_Dimension dim )
+ {
+ FT_Error error;
+
+
+ error = af_latin_hints_compute_segments( hints, dim );
+ if ( !error )
+ {
+ af_latin_hints_link_segments( hints, width_count, widths, dim );
+
+ error = af_latin_hints_compute_edges( hints, dim );
+ }
+
+ return error;
+ }
+
+
+ /* Compute all edges which lie within blue zones. */
+
+ static void
+ af_latin_hints_compute_blue_edges( AF_GlyphHints hints,
+ AF_LatinMetrics metrics )
+ {
+ AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT];
+ AF_Edge edge = axis->edges;
+ AF_Edge edge_limit = edge + axis->num_edges;
+ AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT];
+ FT_Fixed scale = latin->scale;
+
+
+ /* compute which blue zones are active, i.e. have their scaled */
+ /* size < 3/4 pixels */
+
+ /* for each horizontal edge search the blue zone which is closest */
+ for ( ; edge < edge_limit; edge++ )
+ {
+ FT_UInt bb;
+ AF_Width best_blue = NULL;
+ FT_Bool best_blue_is_neutral = 0;
+ FT_Pos best_dist; /* initial threshold */
+
+
+ /* compute the initial threshold as a fraction of the EM size */
+ /* (the value 40 is heuristic) */
+ best_dist = FT_MulFix( metrics->units_per_em / 40, scale );
+
+ /* assure a minimum distance of 0.5px */
+ if ( best_dist > 64 / 2 )
+ best_dist = 64 / 2;
+
+ for ( bb = 0; bb < latin->blue_count; bb++ )
+ {
+ AF_LatinBlue blue = latin->blues + bb;
+ FT_Bool is_top_blue, is_neutral_blue, is_major_dir;
+
+
+ /* skip inactive blue zones (i.e., those that are too large) */
+ if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) )
+ continue;
+
+ /* if it is a top zone, check for right edges (against the major */
+ /* direction); if it is a bottom zone, check for left edges (in */
+ /* the major direction) -- this assumes the TrueType convention */
+ /* for the orientation of contours */
+ is_top_blue =
+ (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 );
+ is_neutral_blue =
+ (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_NEUTRAL ) != 0);
+ is_major_dir =
+ FT_BOOL( edge->dir == axis->major_dir );
+
+ /* neutral blue zones are handled for both directions */
+ if ( is_top_blue ^ is_major_dir || is_neutral_blue )
+ {
+ FT_Pos dist;
+
+
+ /* first of all, compare it to the reference position */
+ dist = edge->fpos - blue->ref.org;
+ if ( dist < 0 )
+ dist = -dist;
+
+ dist = FT_MulFix( dist, scale );
+ if ( dist < best_dist )
+ {
+ best_dist = dist;
+ best_blue = &blue->ref;
+ best_blue_is_neutral = is_neutral_blue;
+ }
+
+ /* now compare it to the overshoot position and check whether */
+ /* the edge is rounded, and whether the edge is over the */
+ /* reference position of a top zone, or under the reference */
+ /* position of a bottom zone (provided we don't have a */
+ /* neutral blue zone) */
+ if ( edge->flags & AF_EDGE_ROUND &&
+ dist != 0 &&
+ !is_neutral_blue )
+ {
+ FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org );
+
+
+ if ( is_top_blue ^ is_under_ref )
+ {
+ dist = edge->fpos - blue->shoot.org;
+ if ( dist < 0 )
+ dist = -dist;
+
+ dist = FT_MulFix( dist, scale );
+ if ( dist < best_dist )
+ {
+ best_dist = dist;
+ best_blue = &blue->shoot;
+ best_blue_is_neutral = is_neutral_blue;
+ }
+ }
+ }
+ }
+ }
+
+ if ( best_blue )
+ {
+ edge->blue_edge = best_blue;
+ if ( best_blue_is_neutral )
+ edge->flags |= AF_EDGE_NEUTRAL;
+ }
+ }
+ }
+
+
+ /* Initalize hinting engine. */
+
+ static FT_Error
+ af_latin_hints_init( AF_GlyphHints hints,
+ AF_LatinMetrics metrics )
+ {
+ FT_Render_Mode mode;
+ FT_UInt32 scaler_flags, other_flags;
+ FT_Face face = metrics->root.scaler.face;
+
+
+ af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics );
+
+ /*
+ * correct x_scale and y_scale if needed, since they may have
+ * been modified by `af_latin_metrics_scale_dim' above
+ */
+ hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale;
+ hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta;
+ hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale;
+ hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta;
+
+ /* compute flags depending on render mode, etc. */
+ mode = metrics->root.scaler.render_mode;
+
+#if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */
+ if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V )
+ metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL;
+#endif
+
+ scaler_flags = hints->scaler_flags;
+ other_flags = 0;
+
+ /*
+ * We snap the width of vertical stems for the monochrome and
+ * horizontal LCD rendering targets only.
+ */
+ if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD )
+ other_flags |= AF_LATIN_HINTS_HORZ_SNAP;
+
+ /*
+ * We snap the width of horizontal stems for the monochrome and
+ * vertical LCD rendering targets only.
+ */
+ if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V )
+ other_flags |= AF_LATIN_HINTS_VERT_SNAP;
+
+ /*
+ * We adjust stems to full pixels only if we don't use the `light' mode.
+ */
+ if ( mode != FT_RENDER_MODE_LIGHT )
+ other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
+
+ if ( mode == FT_RENDER_MODE_MONO )
+ other_flags |= AF_LATIN_HINTS_MONO;
+
+ /*
+ * In `light' hinting mode we disable horizontal hinting completely.
+ * We also do it if the face is italic.
+ *
+ * However, if warping is enabled (which only works in `light' hinting
+ * mode), advance widths get adjusted, too.
+ */
+ if ( mode == FT_RENDER_MODE_LIGHT ||
+ ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 )
+ scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL;
+
+#ifdef AF_CONFIG_OPTION_USE_WARPER
+ /* get (global) warper flag */
+ if ( !metrics->root.globals->module->warping )
+ scaler_flags |= AF_SCALER_FLAG_NO_WARPER;
+#endif
+
+ hints->scaler_flags = scaler_flags;
+ hints->other_flags = other_flags;
+
+ return FT_Err_Ok;
+ }
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** L A T I N G L Y P H G R I D - F I T T I N G *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+ /* Snap a given width in scaled coordinates to one of the */
+ /* current standard widths. */
+
+ static FT_Pos
+ af_latin_snap_width( AF_Width widths,
+ FT_UInt count,
+ FT_Pos width )
+ {
+ FT_UInt n;
+ FT_Pos best = 64 + 32 + 2;
+ FT_Pos reference = width;
+ FT_Pos scaled;
+
+
+ for ( n = 0; n < count; n++ )
+ {
+ FT_Pos w;
+ FT_Pos dist;
+
+
+ w = widths[n].cur;
+ dist = width - w;
+ if ( dist < 0 )
+ dist = -dist;
+ if ( dist < best )
+ {
+ best = dist;
+ reference = w;
+ }
+ }
+
+ scaled = FT_PIX_ROUND( reference );
+
+ if ( width >= reference )
+ {
+ if ( width < scaled + 48 )
+ width = reference;
+ }
+ else
+ {
+ if ( width > scaled - 48 )
+ width = reference;
+ }
+
+ return width;
+ }
+
+
+ /* Compute the snapped width of a given stem, ignoring very thin ones. */
+ /* There is a lot of voodoo in this function; changing the hard-coded */
+ /* parameters influence the whole hinting process. */
+
+ static FT_Pos
+ af_latin_compute_stem_width( AF_GlyphHints hints,
+ AF_Dimension dim,
+ FT_Pos width,
+ FT_UInt base_flags,
+ FT_UInt stem_flags )
+ {
+ AF_LatinMetrics metrics = (AF_LatinMetrics)hints->metrics;
+ AF_LatinAxis axis = &metrics->axis[dim];
+ FT_Pos dist = width;
+ FT_Int sign = 0;
+ FT_Int vertical = ( dim == AF_DIMENSION_VERT );
+
+
+ if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ||
+ axis->extra_light )
+ return width;
+
+ if ( dist < 0 )
+ {
+ dist = -width;
+ sign = 1;
+ }
+
+ if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ||
+ ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) )
+ {
+ /* smooth hinting process: very lightly quantize the stem width */
+
+ /* leave the widths of serifs alone */
+ if ( ( stem_flags & AF_EDGE_SERIF ) &&
+ vertical &&
+ ( dist < 3 * 64 ) )
+ goto Done_Width;
+
+ else if ( base_flags & AF_EDGE_ROUND )
+ {
+ if ( dist < 80 )
+ dist = 64;
+ }
+ else if ( dist < 56 )
+ dist = 56;
+
+ if ( axis->width_count > 0 )
+ {
+ FT_Pos delta;
+
+
+ /* compare to standard width */
+ delta = dist - axis->widths[0].cur;
+
+ if ( delta < 0 )
+ delta = -delta;
+
+ if ( delta < 40 )
+ {
+ dist = axis->widths[0].cur;
+ if ( dist < 48 )
+ dist = 48;
+
+ goto Done_Width;
+ }
+
+ if ( dist < 3 * 64 )
+ {
+ delta = dist & 63;
+ dist &= -64;
+
+ if ( delta < 10 )
+ dist += delta;
+
+ else if ( delta < 32 )
+ dist += 10;
+
+ else if ( delta < 54 )
+ dist += 54;
+
+ else
+ dist += delta;
+ }
+ else
+ dist = ( dist + 32 ) & ~63;
+ }
+ }
+ else
+ {
+ /* strong hinting process: snap the stem width to integer pixels */
+
+ FT_Pos org_dist = dist;
+
+
+ dist = af_latin_snap_width( axis->widths, axis->width_count, dist );
+
+ if ( vertical )
+ {
+ /* in the case of vertical hinting, always round */
+ /* the stem heights to integer pixels */
+
+ if ( dist >= 64 )
+ dist = ( dist + 16 ) & ~63;
+ else
+ dist = 64;
+ }
+ else
+ {
+ if ( AF_LATIN_HINTS_DO_MONO( hints ) )
+ {
+ /* monochrome horizontal hinting: snap widths to integer pixels */
+ /* with a different threshold */
+
+ if ( dist < 64 )
+ dist = 64;
+ else
+ dist = ( dist + 32 ) & ~63;
+ }
+ else
+ {
+ /* for horizontal anti-aliased hinting, we adopt a more subtle */
+ /* approach: we strengthen small stems, round stems whose size */
+ /* is between 1 and 2 pixels to an integer, otherwise nothing */
+
+ if ( dist < 48 )
+ dist = ( dist + 64 ) >> 1;
+
+ else if ( dist < 128 )
+ {
+ /* We only round to an integer width if the corresponding */
+ /* distortion is less than 1/4 pixel. Otherwise this */
+ /* makes everything worse since the diagonals, which are */
+ /* not hinted, appear a lot bolder or thinner than the */
+ /* vertical stems. */
+
+ FT_Pos delta;
+
+
+ dist = ( dist + 22 ) & ~63;
+ delta = dist - org_dist;
+ if ( delta < 0 )
+ delta = -delta;
+
+ if ( delta >= 16 )
+ {
+ dist = org_dist;
+ if ( dist < 48 )
+ dist = ( dist + 64 ) >> 1;
+ }
+ }
+ else
+ /* round otherwise to prevent color fringes in LCD mode */
+ dist = ( dist + 32 ) & ~63;
+ }
+ }
+ }
+
+ Done_Width:
+ if ( sign )
+ dist = -dist;
+
+ return dist;
+ }
+
+
+ /* Align one stem edge relative to the previous stem edge. */
+
+ static void
+ af_latin_align_linked_edge( AF_GlyphHints hints,
+ AF_Dimension dim,
+ AF_Edge base_edge,
+ AF_Edge stem_edge )
+ {
+ FT_Pos dist = stem_edge->opos - base_edge->opos;
+
+ FT_Pos fitted_width = af_latin_compute_stem_width( hints, dim, dist,
+ base_edge->flags,
+ stem_edge->flags );
+
+
+ stem_edge->pos = base_edge->pos + fitted_width;
+
+ FT_TRACE5(( " LINK: edge %d (opos=%.2f) linked to %.2f,"
+ " dist was %.2f, now %.2f\n",
+ stem_edge - hints->axis[dim].edges, stem_edge->opos / 64.0,
+ stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 ));
+ }
+
+
+ /* Shift the coordinates of the `serif' edge by the same amount */
+ /* as the corresponding `base' edge has been moved already. */
+
+ static void
+ af_latin_align_serif_edge( AF_GlyphHints hints,
+ AF_Edge base,
+ AF_Edge serif )
+ {
+ FT_UNUSED( hints );
+
+ serif->pos = base->pos + ( serif->opos - base->opos );
+ }
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /*************************************************************************/
+ /**** ****/
+ /**** E D G E H I N T I N G ****/
+ /**** ****/
+ /*************************************************************************/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ /* The main grid-fitting routine. */
+
+ static void
+ af_latin_hint_edges( AF_GlyphHints hints,
+ AF_Dimension dim )
+ {
+ AF_AxisHints axis = &hints->axis[dim];
+ AF_Edge edges = axis->edges;
+ AF_Edge edge_limit = edges + axis->num_edges;
+ FT_PtrDist n_edges;
+ AF_Edge edge;
+ AF_Edge anchor = NULL;
+ FT_Int has_serifs = 0;
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_UInt num_actions = 0;
+#endif
+
+
+ FT_TRACE5(( "latin %s edge hinting (style `%s')\n",
+ dim == AF_DIMENSION_VERT ? "horizontal" : "vertical",
+ af_style_names[hints->metrics->style_class->style] ));
+
+ /* we begin by aligning all stems relative to the blue zone */
+ /* if needed -- that's only for horizontal edges */
+
+ if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) )
+ {
+ for ( edge = edges; edge < edge_limit; edge++ )
+ {
+ AF_Width blue;
+ AF_Edge edge1, edge2; /* these edges form the stem to check */
+
+
+ if ( edge->flags & AF_EDGE_DONE )
+ continue;
+
+ edge1 = NULL;
+ edge2 = edge->link;
+
+ /*
+ * If a stem contains both a neutral and a non-neutral blue zone,
+ * skip the neutral one. Otherwise, outlines with different
+ * directions might be incorrectly aligned at the same vertical
+ * position.
+ *
+ * If we have two neutral blue zones, skip one of them.
+ *
+ */
+ if ( edge->blue_edge && edge2 && edge2->blue_edge )
+ {
+ FT_Byte neutral = edge->flags & AF_EDGE_NEUTRAL;
+ FT_Byte neutral2 = edge2->flags & AF_EDGE_NEUTRAL;
+
+
+ if ( neutral2 )
+ {
+ edge2->blue_edge = NULL;
+ edge2->flags &= ~AF_EDGE_NEUTRAL;
+ }
+ else if ( neutral )
+ {
+ edge->blue_edge = NULL;
+ edge->flags &= ~AF_EDGE_NEUTRAL;
+ }
+ }
+
+ blue = edge->blue_edge;
+ if ( blue )
+ edge1 = edge;
+
+ /* flip edges if the other edge is aligned to a blue zone */
+ else if ( edge2 && edge2->blue_edge )
+ {
+ blue = edge2->blue_edge;
+ edge1 = edge2;
+ edge2 = edge;
+ }
+
+ if ( !edge1 )
+ continue;
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !anchor )
+ FT_TRACE5(( " BLUE_ANCHOR: edge %d (opos=%.2f) snapped to %.2f,"
+ " was %.2f (anchor=edge %d)\n",
+ edge1 - edges, edge1->opos / 64.0, blue->fit / 64.0,
+ edge1->pos / 64.0, edge - edges ));
+ else
+ FT_TRACE5(( " BLUE: edge %d (opos=%.2f) snapped to %.2f,"
+ " was %.2f\n",
+ edge1 - edges, edge1->opos / 64.0, blue->fit / 64.0,
+ edge1->pos / 64.0 ));
+
+ num_actions++;
+#endif
+
+ edge1->pos = blue->fit;
+ edge1->flags |= AF_EDGE_DONE;
+
+ if ( edge2 && !edge2->blue_edge )
+ {
+ af_latin_align_linked_edge( hints, dim, edge1, edge2 );
+ edge2->flags |= AF_EDGE_DONE;
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ num_actions++;
+#endif
+ }
+
+ if ( !anchor )
+ anchor = edge;
+ }
+ }
+
+ /* now we align all other stem edges, trying to maintain the */
+ /* relative order of stems in the glyph */
+ for ( edge = edges; edge < edge_limit; edge++ )
+ {
+ AF_Edge edge2;
+
+
+ if ( edge->flags & AF_EDGE_DONE )
+ continue;
+
+ /* skip all non-stem edges */
+ edge2 = edge->link;
+ if ( !edge2 )
+ {
+ has_serifs++;
+ continue;
+ }
+
+ /* now align the stem */
+
+ /* this should not happen, but it's better to be safe */
+ if ( edge2->blue_edge )
+ {
+ FT_TRACE5(( " ASSERTION FAILED for edge %d\n", edge2 - edges ));
+
+ af_latin_align_linked_edge( hints, dim, edge2, edge );
+ edge->flags |= AF_EDGE_DONE;
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ num_actions++;
+#endif
+ continue;
+ }
+
+ if ( !anchor )
+ {
+ /* if we reach this if clause, no stem has been aligned yet */
+
+ FT_Pos org_len, org_center, cur_len;
+ FT_Pos cur_pos1, error1, error2, u_off, d_off;
+
+
+ org_len = edge2->opos - edge->opos;
+ cur_len = af_latin_compute_stem_width( hints, dim, org_len,
+ edge->flags,
+ edge2->flags );
+
+ /* some voodoo to specially round edges for small stem widths; */
+ /* the idea is to align the center of a stem, then shifting */
+ /* the stem edges to suitable positions */
+ if ( cur_len <= 64 )
+ {
+ /* width <= 1px */
+ u_off = 32;
+ d_off = 32;
+ }
+ else
+ {
+ /* 1px < width < 1.5px */
+ u_off = 38;
+ d_off = 26;
+ }
+
+ if ( cur_len < 96 )
+ {
+ org_center = edge->opos + ( org_len >> 1 );
+ cur_pos1 = FT_PIX_ROUND( org_center );
+
+ error1 = org_center - ( cur_pos1 - u_off );
+ if ( error1 < 0 )
+ error1 = -error1;
+
+ error2 = org_center - ( cur_pos1 + d_off );
+ if ( error2 < 0 )
+ error2 = -error2;
+
+ if ( error1 < error2 )
+ cur_pos1 -= u_off;
+ else
+ cur_pos1 += d_off;
+
+ edge->pos = cur_pos1 - cur_len / 2;
+ edge2->pos = edge->pos + cur_len;
+ }
+ else
+ edge->pos = FT_PIX_ROUND( edge->opos );
+
+ anchor = edge;
+ edge->flags |= AF_EDGE_DONE;
+
+ FT_TRACE5(( " ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)"
+ " snapped to %.2f and %.2f\n",
+ edge - edges, edge->opos / 64.0,
+ edge2 - edges, edge2->opos / 64.0,
+ edge->pos / 64.0, edge2->pos / 64.0 ));
+
+ af_latin_align_linked_edge( hints, dim, edge, edge2 );
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ num_actions += 2;
+#endif
+ }
+ else
+ {
+ FT_Pos org_pos, org_len, org_center, cur_len;
+ FT_Pos cur_pos1, cur_pos2, delta1, delta2;
+
+
+ org_pos = anchor->pos + ( edge->opos - anchor->opos );
+ org_len = edge2->opos - edge->opos;
+ org_center = org_pos + ( org_len >> 1 );
+
+ cur_len = af_latin_compute_stem_width( hints, dim, org_len,
+ edge->flags,
+ edge2->flags );
+
+ if ( edge2->flags & AF_EDGE_DONE )
+ {
+ FT_TRACE5(( " ADJUST: edge %d (pos=%.2f) moved to %.2f\n",
+ edge - edges, edge->pos / 64.0,
+ ( edge2->pos - cur_len ) / 64.0 ));
+
+ edge->pos = edge2->pos - cur_len;
+ }
+
+ else if ( cur_len < 96 )
+ {
+ FT_Pos u_off, d_off;
+
+
+ cur_pos1 = FT_PIX_ROUND( org_center );
+
+ if ( cur_len <= 64 )
+ {
+ u_off = 32;
+ d_off = 32;
+ }
+ else
+ {
+ u_off = 38;
+ d_off = 26;
+ }
+
+ delta1 = org_center - ( cur_pos1 - u_off );
+ if ( delta1 < 0 )
+ delta1 = -delta1;
+
+ delta2 = org_center - ( cur_pos1 + d_off );
+ if ( delta2 < 0 )
+ delta2 = -delta2;
+
+ if ( delta1 < delta2 )
+ cur_pos1 -= u_off;
+ else
+ cur_pos1 += d_off;
+
+ edge->pos = cur_pos1 - cur_len / 2;
+ edge2->pos = cur_pos1 + cur_len / 2;
+
+ FT_TRACE5(( " STEM: edge %d (opos=%.2f) linked to %d (opos=%.2f)"
+ " snapped to %.2f and %.2f\n",
+ edge - edges, edge->opos / 64.0,
+ edge2 - edges, edge2->opos / 64.0,
+ edge->pos / 64.0, edge2->pos / 64.0 ));
+ }
+
+ else
+ {
+ org_pos = anchor->pos + ( edge->opos - anchor->opos );
+ org_len = edge2->opos - edge->opos;
+ org_center = org_pos + ( org_len >> 1 );
+
+ cur_len = af_latin_compute_stem_width( hints, dim, org_len,
+ edge->flags,
+ edge2->flags );
+
+ cur_pos1 = FT_PIX_ROUND( org_pos );
+ delta1 = cur_pos1 + ( cur_len >> 1 ) - org_center;
+ if ( delta1 < 0 )
+ delta1 = -delta1;
+
+ cur_pos2 = FT_PIX_ROUND( org_pos + org_len ) - cur_len;
+ delta2 = cur_pos2 + ( cur_len >> 1 ) - org_center;
+ if ( delta2 < 0 )
+ delta2 = -delta2;
+
+ edge->pos = ( delta1 < delta2 ) ? cur_pos1 : cur_pos2;
+ edge2->pos = edge->pos + cur_len;
+
+ FT_TRACE5(( " STEM: edge %d (opos=%.2f) linked to %d (opos=%.2f)"
+ " snapped to %.2f and %.2f\n",
+ edge - edges, edge->opos / 64.0,
+ edge2 - edges, edge2->opos / 64.0,
+ edge->pos / 64.0, edge2->pos / 64.0 ));
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ num_actions++;
+#endif
+
+ edge->flags |= AF_EDGE_DONE;
+ edge2->flags |= AF_EDGE_DONE;
+
+ if ( edge > edges && edge->pos < edge[-1].pos )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE5(( " BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+ edge - edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
+
+ num_actions++;
+#endif
+
+ edge->pos = edge[-1].pos;
+ }
+ }
+ }
+
+ /* make sure that lowercase m's maintain their symmetry */
+
+ /* In general, lowercase m's have six vertical edges if they are sans */
+ /* serif, or twelve if they are with serifs. This implementation is */
+ /* based on that assumption, and seems to work very well with most */
+ /* faces. However, if for a certain face this assumption is not */
+ /* true, the m is just rendered like before. In addition, any stem */
+ /* correction will only be applied to symmetrical glyphs (even if the */
+ /* glyph is not an m), so the potential for unwanted distortion is */
+ /* relatively low. */
+
+ /* We don't handle horizontal edges since we can't easily assure that */
+ /* the third (lowest) stem aligns with the base line; it might end up */
+ /* one pixel higher or lower. */
+
+ n_edges = edge_limit - edges;
+ if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) )
+ {
+ AF_Edge edge1, edge2, edge3;
+ FT_Pos dist1, dist2, span, delta;
+
+
+ if ( n_edges == 6 )
+ {
+ edge1 = edges;
+ edge2 = edges + 2;
+ edge3 = edges + 4;
+ }
+ else
+ {
+ edge1 = edges + 1;
+ edge2 = edges + 5;
+ edge3 = edges + 9;
+ }
+
+ dist1 = edge2->opos - edge1->opos;
+ dist2 = edge3->opos - edge2->opos;
+
+ span = dist1 - dist2;
+ if ( span < 0 )
+ span = -span;
+
+ if ( span < 8 )
+ {
+ delta = edge3->pos - ( 2 * edge2->pos - edge1->pos );
+ edge3->pos -= delta;
+ if ( edge3->link )
+ edge3->link->pos -= delta;
+
+ /* move the serifs along with the stem */
+ if ( n_edges == 12 )
+ {
+ ( edges + 8 )->pos -= delta;
+ ( edges + 11 )->pos -= delta;
+ }
+
+ edge3->flags |= AF_EDGE_DONE;
+ if ( edge3->link )
+ edge3->link->flags |= AF_EDGE_DONE;
+ }
+ }
+
+ if ( has_serifs || !anchor )
+ {
+ /*
+ * now hint the remaining edges (serifs and single) in order
+ * to complete our processing
+ */
+ for ( edge = edges; edge < edge_limit; edge++ )
+ {
+ FT_Pos delta;
+
+
+ if ( edge->flags & AF_EDGE_DONE )
+ continue;
+
+ delta = 1000;
+
+ if ( edge->serif )
+ {
+ delta = edge->serif->opos - edge->opos;
+ if ( delta < 0 )
+ delta = -delta;
+ }
+
+ if ( delta < 64 + 16 )
+ {
+ af_latin_align_serif_edge( hints, edge->serif, edge );
+ FT_TRACE5(( " SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)"
+ " aligned to %.2f\n",
+ edge - edges, edge->opos / 64.0,
+ edge->serif - edges, edge->serif->opos / 64.0,
+ edge->pos / 64.0 ));
+ }
+ else if ( !anchor )
+ {
+ edge->pos = FT_PIX_ROUND( edge->opos );
+ anchor = edge;
+ FT_TRACE5(( " SERIF_ANCHOR: edge %d (opos=%.2f)"
+ " snapped to %.2f\n",
+ edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
+ }
+ else
+ {
+ AF_Edge before, after;
+
+
+ for ( before = edge - 1; before >= edges; before-- )
+ if ( before->flags & AF_EDGE_DONE )
+ break;
+
+ for ( after = edge + 1; after < edge_limit; after++ )
+ if ( after->flags & AF_EDGE_DONE )
+ break;
+
+ if ( before >= edges && before < edge &&
+ after < edge_limit && after > edge )
+ {
+ if ( after->opos == before->opos )
+ edge->pos = before->pos;
+ else
+ edge->pos = before->pos +
+ FT_MulDiv( edge->opos - before->opos,
+ after->pos - before->pos,
+ after->opos - before->opos );
+
+ FT_TRACE5(( " SERIF_LINK1: edge %d (opos=%.2f) snapped to %.2f"
+ " from %d (opos=%.2f)\n",
+ edge - edges, edge->opos / 64.0,
+ edge->pos / 64.0,
+ before - edges, before->opos / 64.0 ));
+ }
+ else
+ {
+ edge->pos = anchor->pos +
+ ( ( edge->opos - anchor->opos + 16 ) & ~31 );
+ FT_TRACE5(( " SERIF_LINK2: edge %d (opos=%.2f)"
+ " snapped to %.2f\n",
+ edge - edges, edge->opos / 64.0, edge->pos / 64.0 ));
+ }
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ num_actions++;
+#endif
+ edge->flags |= AF_EDGE_DONE;
+
+ if ( edge > edges && edge->pos < edge[-1].pos )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE5(( " BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+ edge - edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
+
+ num_actions++;
+#endif
+ edge->pos = edge[-1].pos;
+ }
+
+ if ( edge + 1 < edge_limit &&
+ edge[1].flags & AF_EDGE_DONE &&
+ edge->pos > edge[1].pos )
+ {
+#ifdef FT_DEBUG_LEVEL_TRACE
+ FT_TRACE5(( " BOUND: edge %d (pos=%.2f) moved to %.2f\n",
+ edge - edges, edge->pos / 64.0, edge[1].pos / 64.0 ));
+
+ num_actions++;
+#endif
+
+ edge->pos = edge[1].pos;
+ }
+ }
+ }
+
+#ifdef FT_DEBUG_LEVEL_TRACE
+ if ( !num_actions )
+ FT_TRACE5(( " (none)\n" ));
+ FT_TRACE5(( "\n" ));
+#endif
+ }
+
+
+ /* Apply the complete hinting algorithm to a latin glyph. */
+
+ static FT_Error
+ af_latin_hints_apply( AF_GlyphHints hints,
+ FT_Outline* outline,
+ AF_LatinMetrics metrics )
+ {
+ FT_Error error;
+ int dim;
+
+ AF_LatinAxis axis;
+
+
+ error = af_glyph_hints_reload( hints, outline );
+ if ( error )
+ goto Exit;
+
+ /* analyze glyph outline */
+#ifdef AF_CONFIG_OPTION_USE_WARPER
+ if ( ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT &&
+ AF_HINTS_DO_WARP( hints ) ) ||
+ AF_HINTS_DO_HORIZONTAL( hints ) )
+#else
+ if ( AF_HINTS_DO_HORIZONTAL( hints ) )
+#endif
+ {
+ axis = &metrics->axis[AF_DIMENSION_HORZ];
+ error = af_latin_hints_detect_features( hints,
+ axis->width_count,
+ axis->widths,
+ AF_DIMENSION_HORZ );
+ if ( error )
+ goto Exit;
+ }
+
+ if ( AF_HINTS_DO_VERTICAL( hints ) )
+ {
+ axis = &metrics->axis[AF_DIMENSION_VERT];
+ error = af_latin_hints_detect_features( hints,
+ axis->width_count,
+ axis->widths,
+ AF_DIMENSION_VERT );
+ if ( error )
+ goto Exit;
+
+ af_latin_hints_compute_blue_edges( hints, metrics );
+ }
+
+ /* grid-fit the outline */
+ for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
+ {
+#ifdef AF_CONFIG_OPTION_USE_WARPER
+ if ( dim == AF_DIMENSION_HORZ &&
+ metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT &&
+ AF_HINTS_DO_WARP( hints ) )
+ {
+ AF_WarperRec warper;
+ FT_Fixed scale;
+ FT_Pos delta;
+
+
+ af_warper_compute( &warper, hints, (AF_Dimension)dim,
+ &scale, &delta );
+ af_glyph_hints_scale_dim( hints, (AF_Dimension)dim,
+ scale, delta );
+ continue;
+ }
+#endif /* AF_CONFIG_OPTION_USE_WARPER */
+
+ if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
+ ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) )
+ {
+ af_latin_hint_edges( hints, (AF_Dimension)dim );
+ af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim );
+ af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
+ af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim );
+ }
+ }
+
+ af_glyph_hints_save( hints, outline );
+
+ Exit:
+ return error;
+ }
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /***** *****/
+ /***** L A T I N S C R I P T C L A S S *****/
+ /***** *****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ AF_DEFINE_WRITING_SYSTEM_CLASS(
+ af_latin_writing_system_class,
+
+ AF_WRITING_SYSTEM_LATIN,
+
+ sizeof ( AF_LatinMetricsRec ),
+
+ (AF_WritingSystem_InitMetricsFunc) af_latin_metrics_init,
+ (AF_WritingSystem_ScaleMetricsFunc)af_latin_metrics_scale,
+ (AF_WritingSystem_DoneMetricsFunc) NULL,
+
+ (AF_WritingSystem_InitHintsFunc) af_latin_hints_init,
+ (AF_WritingSystem_ApplyHintsFunc) af_latin_hints_apply
+ )
+
+
+/* END */