diff options
Diffstat (limited to 'src/3rdparty/freetype/src/autofit/afloader.c')
| -rw-r--r-- | src/3rdparty/freetype/src/autofit/afloader.c | 585 |
1 files changed, 449 insertions, 136 deletions
diff --git a/src/3rdparty/freetype/src/autofit/afloader.c b/src/3rdparty/freetype/src/autofit/afloader.c index 722ffd31ec..a55550b338 100644 --- a/src/3rdparty/freetype/src/autofit/afloader.c +++ b/src/3rdparty/freetype/src/autofit/afloader.c @@ -4,7 +4,7 @@ /* */ /* Auto-fitter glyph loading routines (body). */ /* */ -/* Copyright 2003-2015 by */ +/* Copyright 2003-2018 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ @@ -23,6 +23,8 @@ #include "afmodule.h" #include "afpic.h" +#include FT_INTERNAL_CALC_H + /* Initialize glyph loader. */ @@ -49,7 +51,7 @@ loader->face = face; loader->globals = (AF_FaceGlobals)face->autohint.data; - if ( loader->globals == NULL ) + if ( !loader->globals ) { error = af_face_globals_new( face, &loader->globals, module ); if ( !error ) @@ -76,41 +78,324 @@ } - /* Do the main work of `af_loader_load_glyph'. Note that we never */ - /* have to deal with composite glyphs as those get loaded into */ - /* FT_GLYPH_FORMAT_OUTLINE by the recursed `FT_Load_Glyph' function. */ - /* In the rare cases where FT_LOAD_NO_RECURSE is set, it implies */ - /* FT_LOAD_NO_SCALE and as such the auto-hinter is never called. */ +#define af_intToFixed( i ) \ + ( (FT_Fixed)( (FT_UInt32)(i) << 16 ) ) +#define af_fixedToInt( x ) \ + ( (FT_Short)( ( (FT_UInt32)(x) + 0x8000U ) >> 16 ) ) +#define af_floatToFixed( f ) \ + ( (FT_Fixed)( (f) * 65536.0 + 0.5 ) ) + static FT_Error - af_loader_load_g( AF_Loader loader, - AF_Scaler scaler, - FT_UInt glyph_index, - FT_Int32 load_flags ) + af_loader_embolden_glyph_in_slot( AF_Loader loader, + FT_Face face, + AF_StyleMetrics style_metrics ) { - FT_Error error; - FT_Face face = loader->face; - AF_StyleMetrics metrics = loader->metrics; - AF_GlyphHints hints = loader->hints; - FT_GlyphSlot slot = face->glyph; - FT_Slot_Internal internal = slot->internal; - FT_GlyphLoader gloader = internal->loader; - FT_Int32 flags; - - - flags = load_flags | FT_LOAD_LINEAR_DESIGN; - error = FT_Load_Glyph( face, glyph_index, flags ); + FT_Error error = FT_Err_Ok; + + FT_GlyphSlot slot = face->glyph; + AF_FaceGlobals globals = loader->globals; + AF_WritingSystemClass writing_system_class; + + FT_Size_Metrics* size_metrics = &face->size->internal->autohint_metrics; + + FT_Pos stdVW = 0; + FT_Pos stdHW = 0; + + FT_Bool size_changed = size_metrics->x_ppem != + globals->stem_darkening_for_ppem; + + FT_Fixed em_size = af_intToFixed( face->units_per_EM ); + FT_Fixed em_ratio = FT_DivFix( af_intToFixed( 1000 ), em_size ); + + FT_Matrix scale_down_matrix = { 0x10000L, 0, 0, 0x10000L }; + + + /* Skip stem darkening for broken fonts. */ + if ( !face->units_per_EM ) + { + error = FT_ERR( Corrupted_Font_Header ); + goto Exit; + } + + /* + * We depend on the writing system (script analyzers) to supply + * standard widths for the script of the glyph we are looking at. If + * it can't deliver, stem darkening is disabled. + */ + writing_system_class = + AF_WRITING_SYSTEM_CLASSES_GET[style_metrics->style_class->writing_system]; + + if ( writing_system_class->style_metrics_getstdw ) + writing_system_class->style_metrics_getstdw( style_metrics, + &stdHW, + &stdVW ); + else + { + error = FT_ERR( Unimplemented_Feature ); + goto Exit; + } + + if ( size_changed || + ( stdVW > 0 && stdVW != globals->standard_vertical_width ) ) + { + FT_Fixed darken_by_font_units_x, darken_x; + + + darken_by_font_units_x = + af_intToFixed( af_loader_compute_darkening( loader, + face, + stdVW ) ); + darken_x = FT_DivFix( FT_MulFix( darken_by_font_units_x, + size_metrics->x_scale ), + em_ratio ); + + globals->standard_vertical_width = stdVW; + globals->stem_darkening_for_ppem = size_metrics->x_ppem; + globals->darken_x = af_fixedToInt( darken_x ); + } + + if ( size_changed || + ( stdHW > 0 && stdHW != globals->standard_horizontal_width ) ) + { + FT_Fixed darken_by_font_units_y, darken_y; + + + darken_by_font_units_y = + af_intToFixed( af_loader_compute_darkening( loader, + face, + stdHW ) ); + darken_y = FT_DivFix( FT_MulFix( darken_by_font_units_y, + size_metrics->y_scale ), + em_ratio ); + + globals->standard_horizontal_width = stdHW; + globals->stem_darkening_for_ppem = size_metrics->x_ppem; + globals->darken_y = af_fixedToInt( darken_y ); + + /* + * Scale outlines down on the Y-axis to keep them inside their blue + * zones. The stronger the emboldening, the stronger the downscaling + * (plus heuristical padding to prevent outlines still falling out + * their zones due to rounding). + * + * Reason: `FT_Outline_Embolden' works by shifting the rightmost + * points of stems farther to the right, and topmost points farther + * up. This positions points on the Y-axis outside their + * pre-computed blue zones and leads to distortion when applying the + * hints in the code further below. Code outside this emboldening + * block doesn't know we are presenting it with modified outlines the + * analyzer didn't see! + * + * An unfortunate side effect of downscaling is that the emboldening + * effect is slightly decreased. The loss becomes more pronounced + * versus the CFF driver at smaller sizes, e.g., at 9ppem and below. + */ + globals->scale_down_factor = + FT_DivFix( em_size - ( darken_by_font_units_y + af_intToFixed( 8 ) ), + em_size ); + } + + FT_Outline_EmboldenXY( &slot->outline, + globals->darken_x, + globals->darken_y ); + + scale_down_matrix.yy = globals->scale_down_factor; + FT_Outline_Transform( &slot->outline, &scale_down_matrix ); + + Exit: + return error; + } + + + /* Load the glyph at index into the current slot of a face and hint it. */ + + FT_LOCAL_DEF( FT_Error ) + af_loader_load_glyph( AF_Loader loader, + AF_Module module, + FT_Face face, + FT_UInt glyph_index, + FT_Int32 load_flags ) + { + FT_Error error; + + FT_Size size = face->size; + FT_Size_Internal size_internal = size->internal; + FT_GlyphSlot slot = face->glyph; + FT_Slot_Internal slot_internal = slot->internal; + FT_GlyphLoader gloader = slot_internal->loader; + + AF_GlyphHints hints = loader->hints; + AF_ScalerRec scaler; + AF_StyleMetrics style_metrics; + FT_UInt style_options = AF_STYLE_NONE_DFLT; + AF_StyleClass style_class; + AF_WritingSystemClass writing_system_class; + +#ifdef FT_CONFIG_OPTION_PIC + AF_FaceGlobals globals = loader->globals; +#endif + + + if ( !size ) + return FT_THROW( Invalid_Size_Handle ); + + FT_ZERO( &scaler ); + + if ( !size_internal->autohint_metrics.x_scale || + size_internal->autohint_mode != FT_LOAD_TARGET_MODE( load_flags ) ) + { + /* switching between hinting modes usually means different scaling */ + /* values; this later on enforces recomputation of everything */ + /* related to the current size */ + + size_internal->autohint_mode = FT_LOAD_TARGET_MODE( load_flags ); + size_internal->autohint_metrics = size->metrics; + +#ifdef AF_CONFIG_OPTION_TT_SIZE_METRICS + { + FT_Size_Metrics* size_metrics = &size_internal->autohint_metrics; + + + /* set metrics to integer values and adjust scaling accordingly; */ + /* this is the same setup as with TrueType fonts, cf. function */ + /* `tt_size_reset' in file `ttobjs.c' */ + size_metrics->ascender = FT_PIX_ROUND( + FT_MulFix( face->ascender, + size_metrics->y_scale ) ); + size_metrics->descender = FT_PIX_ROUND( + FT_MulFix( face->descender, + size_metrics->y_scale ) ); + size_metrics->height = FT_PIX_ROUND( + FT_MulFix( face->height, + size_metrics->y_scale ) ); + + size_metrics->x_scale = FT_DivFix( size_metrics->x_ppem << 6, + face->units_per_EM ); + size_metrics->y_scale = FT_DivFix( size_metrics->y_ppem << 6, + face->units_per_EM ); + size_metrics->max_advance = FT_PIX_ROUND( + FT_MulFix( face->max_advance_width, + size_metrics->x_scale ) ); + } +#endif /* AF_CONFIG_OPTION_TT_SIZE_METRICS */ + } + + /* + * TODO: This code currently doesn't support fractional advance widths, + * i.e., placing hinted glyphs at anything other than integer + * x-positions. This is only relevant for the warper code, which + * scales and shifts glyphs to optimize blackness of stems (hinting on + * the x-axis by nature places things on pixel integers, hinting on the + * y-axis only, i.e., LIGHT mode, doesn't touch the x-axis). The delta + * values of the scaler would need to be adjusted. + */ + scaler.face = face; + scaler.x_scale = size_internal->autohint_metrics.x_scale; + scaler.x_delta = 0; + scaler.y_scale = size_internal->autohint_metrics.y_scale; + scaler.y_delta = 0; + + scaler.render_mode = FT_LOAD_TARGET_MODE( load_flags ); + scaler.flags = 0; + + /* note that the fallback style can't be changed anymore */ + /* after the first call of `af_loader_load_glyph' */ + error = af_loader_reset( loader, module, face ); + if ( error ) + goto Exit; + +#ifdef FT_OPTION_AUTOFIT2 + /* XXX: undocumented hook to activate the latin2 writing system. */ + if ( load_flags & ( 1UL << 20 ) ) + style_options = AF_STYLE_LTN2_DFLT; +#endif + + /* + * Glyphs (really code points) are assigned to scripts. Script + * analysis is done lazily: For each glyph that passes through here, + * the corresponding script analyzer is called, but returns immediately + * if it has been run already. + */ + error = af_face_globals_get_metrics( loader->globals, glyph_index, + style_options, &style_metrics ); + if ( error ) + goto Exit; + + style_class = style_metrics->style_class; + writing_system_class = + AF_WRITING_SYSTEM_CLASSES_GET[style_class->writing_system]; + + loader->metrics = style_metrics; + + if ( writing_system_class->style_metrics_scale ) + writing_system_class->style_metrics_scale( style_metrics, &scaler ); + else + style_metrics->scaler = scaler; + + if ( writing_system_class->style_hints_init ) + { + error = writing_system_class->style_hints_init( hints, + style_metrics ); + if ( error ) + goto Exit; + } + + /* + * Do the main work of `af_loader_load_glyph'. Note that we never have + * to deal with composite glyphs as those get loaded into + * FT_GLYPH_FORMAT_OUTLINE by the recursed `FT_Load_Glyph' function. + * In the rare cases where FT_LOAD_NO_RECURSE is set, it implies + * FT_LOAD_NO_SCALE and as such the auto-hinter is never called. + */ + load_flags |= FT_LOAD_NO_SCALE | + FT_LOAD_IGNORE_TRANSFORM | + FT_LOAD_LINEAR_DESIGN; + load_flags &= ~FT_LOAD_RENDER; + + error = FT_Load_Glyph( face, glyph_index, load_flags ); if ( error ) goto Exit; - loader->transformed = internal->glyph_transformed; + /* + * Apply stem darkening (emboldening) here before hints are applied to + * the outline. Glyphs are scaled down proportionally to the + * emboldening so that curve points don't fall outside their + * precomputed blue zones. + * + * Any emboldening done by the font driver (e.g., the CFF driver) + * doesn't reach here because the autohinter loads the unprocessed + * glyphs in font units for analysis (functions `af_*_metrics_init_*') + * and then above to prepare it for the rasterizers by itself, + * independently of the font driver. So emboldening must be done here, + * within the autohinter. + * + * All glyphs to be autohinted pass through here one by one. The + * standard widths can therefore change from one glyph to the next, + * depending on what script a glyph is assigned to (each script has its + * own set of standard widths and other metrics). The darkening amount + * must therefore be recomputed for each size and + * `standard_{vertical,horizontal}_width' change. + * + * Ignore errors and carry on without emboldening. + * + */ + + /* stem darkening only works well in `light' mode */ + if ( scaler.render_mode == FT_RENDER_MODE_LIGHT && + ( !face->internal->no_stem_darkening || + ( face->internal->no_stem_darkening < 0 && + !module->no_stem_darkening ) ) ) + af_loader_embolden_glyph_in_slot( loader, face, style_metrics ); + + loader->transformed = slot_internal->glyph_transformed; if ( loader->transformed ) { FT_Matrix inverse; - loader->trans_matrix = internal->glyph_matrix; - loader->trans_delta = internal->glyph_delta; + loader->trans_matrix = slot_internal->glyph_matrix; + loader->trans_delta = slot_internal->glyph_delta; inverse = loader->trans_matrix; if ( !FT_Matrix_Invert( &inverse ) ) @@ -126,8 +411,8 @@ loader->trans_delta.x, loader->trans_delta.y ); - /* compute original horizontal phantom points (and ignore */ - /* vertical ones) */ + /* compute original horizontal phantom points */ + /* (and ignore vertical ones) */ loader->pp1.x = hints->x_delta; loader->pp1.y = hints->y_delta; loader->pp2.x = FT_MulFix( slot->metrics.horiAdvance, @@ -138,30 +423,21 @@ if ( slot->outline.n_points == 0 ) goto Hint_Metrics; - /* now load the slot image into the auto-outline and run the */ - /* automatic hinting process */ - { -#ifdef FT_CONFIG_OPTION_PIC - AF_FaceGlobals globals = loader->globals; -#endif - AF_StyleClass style_class = metrics->style_class; - AF_WritingSystemClass writing_system_class = - AF_WRITING_SYSTEM_CLASSES_GET[style_class->writing_system]; - - - if ( writing_system_class->style_hints_apply ) - writing_system_class->style_hints_apply( glyph_index, - hints, - &gloader->base.outline, - metrics ); - } + /* now load the slot image into the auto-outline */ + /* and run the automatic hinting process */ + if ( writing_system_class->style_hints_apply ) + writing_system_class->style_hints_apply( glyph_index, + hints, + &gloader->base.outline, + style_metrics ); /* we now need to adjust the metrics according to the change in */ /* width/positioning that occurred during the hinting process */ - if ( scaler->render_mode != FT_RENDER_MODE_LIGHT ) + if ( scaler.render_mode != FT_RENDER_MODE_LIGHT ) { - FT_Pos old_rsb, old_lsb, new_lsb; - FT_Pos pp1x_uh, pp2x_uh; + FT_Pos old_rsb, old_lsb, new_lsb; + FT_Pos pp1x_uh, pp2x_uh; + AF_AxisHints axis = &hints->axis[AF_DIMENSION_HORZ]; AF_Edge edge1 = axis->edges; /* leftmost edge */ AF_Edge edge2 = edge1 + @@ -171,12 +447,12 @@ if ( axis->num_edges > 1 && AF_HINTS_DO_ADVANCE( hints ) ) { old_rsb = loader->pp2.x - edge2->opos; - old_lsb = edge1->opos; + /* loader->pp1.x is always zero at this point of time */ + old_lsb = edge1->opos /* - loader->pp1.x */; new_lsb = edge1->pos; /* remember unhinted values to later account */ /* for rounding errors */ - pp1x_uh = new_lsb - old_lsb; pp2x_uh = edge2->pos + old_rsb; @@ -207,21 +483,23 @@ FT_Pos pp2x = loader->pp2.x; - loader->pp1.x = FT_PIX_ROUND( pp1x ); - loader->pp2.x = FT_PIX_ROUND( pp2x ); + loader->pp1.x = FT_PIX_ROUND( pp1x + hints->xmin_delta ); + loader->pp2.x = FT_PIX_ROUND( pp2x + hints->xmax_delta ); slot->lsb_delta = loader->pp1.x - pp1x; slot->rsb_delta = loader->pp2.x - pp2x; } } + /* `light' mode uses integer advance widths */ + /* but sets `lsb_delta' and `rsb_delta' */ else { FT_Pos pp1x = loader->pp1.x; FT_Pos pp2x = loader->pp2.x; - loader->pp1.x = FT_PIX_ROUND( pp1x + hints->xmin_delta ); - loader->pp2.x = FT_PIX_ROUND( pp2x + hints->xmax_delta ); + loader->pp1.x = FT_PIX_ROUND( pp1x ); + loader->pp2.x = FT_PIX_ROUND( pp2x ); slot->lsb_delta = loader->pp1.x - pp1x; slot->rsb_delta = loader->pp2.x - pp2x; @@ -242,8 +520,8 @@ vvector.x = slot->metrics.vertBearingX - slot->metrics.horiBearingX; vvector.y = slot->metrics.vertBearingY - slot->metrics.horiBearingY; - vvector.x = FT_MulFix( vvector.x, metrics->scaler.x_scale ); - vvector.y = FT_MulFix( vvector.y, metrics->scaler.y_scale ); + vvector.x = FT_MulFix( vvector.x, style_metrics->scaler.x_scale ); + vvector.y = FT_MulFix( vvector.y, style_metrics->scaler.y_scale ); /* transform the hinted outline if needed */ if ( loader->transformed ) @@ -251,12 +529,12 @@ FT_Outline_Transform( &gloader->base.outline, &loader->trans_matrix ); FT_Vector_Transform( &vvector, &loader->trans_matrix ); } -#if 1 + /* we must translate our final outline by -pp1.x and compute */ /* the new metrics */ if ( loader->pp1.x ) FT_Outline_Translate( &gloader->base.outline, -loader->pp1.x, 0 ); -#endif + FT_Outline_Get_CBox( &gloader->base.outline, &bbox ); bbox.xMin = FT_PIX_FLOOR( bbox.xMin ); @@ -275,20 +553,14 @@ /* for mono-width fonts (like Andale, Courier, etc.) we need */ /* to keep the original rounded advance width; ditto for */ /* digits if all have the same advance width */ -#if 0 - if ( !FT_IS_FIXED_WIDTH( slot->face ) ) - slot->metrics.horiAdvance = loader->pp2.x - loader->pp1.x; - else - slot->metrics.horiAdvance = FT_MulFix( slot->metrics.horiAdvance, - x_scale ); -#else - if ( scaler->render_mode != FT_RENDER_MODE_LIGHT && + if ( scaler.render_mode != FT_RENDER_MODE_LIGHT && ( FT_IS_FIXED_WIDTH( slot->face ) || ( af_face_globals_is_digit( loader->globals, glyph_index ) && - metrics->digits_have_same_width ) ) ) + style_metrics->digits_have_same_width ) ) ) { - slot->metrics.horiAdvance = FT_MulFix( slot->metrics.horiAdvance, - metrics->scaler.x_scale ); + slot->metrics.horiAdvance = + FT_MulFix( slot->metrics.horiAdvance, + style_metrics->scaler.x_scale ); /* Set delta values to 0. Otherwise code that uses them is */ /* going to ruin the fixed advance width. */ @@ -301,23 +573,13 @@ if ( slot->metrics.horiAdvance ) slot->metrics.horiAdvance = loader->pp2.x - loader->pp1.x; } -#endif slot->metrics.vertAdvance = FT_MulFix( slot->metrics.vertAdvance, - metrics->scaler.y_scale ); + style_metrics->scaler.y_scale ); slot->metrics.horiAdvance = FT_PIX_ROUND( slot->metrics.horiAdvance ); slot->metrics.vertAdvance = FT_PIX_ROUND( slot->metrics.vertAdvance ); -#if 0 - /* reassign all outline fields except flags to protect them */ - slot->outline.n_contours = internal->loader->base.outline.n_contours; - slot->outline.n_points = internal->loader->base.outline.n_points; - slot->outline.points = internal->loader->base.outline.points; - slot->outline.tags = internal->loader->base.outline.tags; - slot->outline.contours = internal->loader->base.outline.contours; -#endif - slot->format = FT_GLYPH_FORMAT_OUTLINE; } @@ -326,82 +588,133 @@ } - /* Load a glyph. */ - - FT_LOCAL_DEF( FT_Error ) - af_loader_load_glyph( AF_Loader loader, - AF_Module module, - FT_Face face, - FT_UInt gindex, - FT_Int32 load_flags ) + /* + * Compute amount of font units the face should be emboldened by, in + * analogy to the CFF driver's `cf2_computeDarkening' function. See there + * for details of the algorithm. + * + * XXX: Currently a crude adaption of the original algorithm. Do better? + */ + FT_LOCAL_DEF( FT_Int32 ) + af_loader_compute_darkening( AF_Loader loader, + FT_Face face, + FT_Pos standard_width ) { - FT_Error error; - FT_Size size = face->size; - AF_ScalerRec scaler; + AF_Module module = loader->globals->module; + FT_UShort units_per_EM; + FT_Fixed ppem, em_ratio; + FT_Fixed stem_width, stem_width_per_1000, scaled_stem, darken_amount; + FT_Int log_base_2; + FT_Int x1, y1, x2, y2, x3, y3, x4, y4; - if ( !size ) - return FT_THROW( Invalid_Size_Handle ); - FT_ZERO( &scaler ); + ppem = FT_MAX( af_intToFixed( 4 ), + af_intToFixed( face->size->metrics.x_ppem ) ); + units_per_EM = face->units_per_EM; - scaler.face = face; - scaler.x_scale = size->metrics.x_scale; - scaler.x_delta = 0; /* XXX: TODO: add support for sub-pixel hinting */ - scaler.y_scale = size->metrics.y_scale; - scaler.y_delta = 0; /* XXX: TODO: add support for sub-pixel hinting */ + em_ratio = FT_DivFix( af_intToFixed( 1000 ), + af_intToFixed ( units_per_EM ) ); + if ( em_ratio < af_floatToFixed( .01 ) ) + { + /* If something goes wrong, don't embolden. */ + return 0; + } - scaler.render_mode = FT_LOAD_TARGET_MODE( load_flags ); - scaler.flags = 0; /* XXX: fix this */ + x1 = module->darken_params[0]; + y1 = module->darken_params[1]; + x2 = module->darken_params[2]; + y2 = module->darken_params[3]; + x3 = module->darken_params[4]; + y3 = module->darken_params[5]; + x4 = module->darken_params[6]; + y4 = module->darken_params[7]; - error = af_loader_reset( loader, module, face ); - if ( !error ) + if ( standard_width <= 0 ) + { + stem_width = af_intToFixed( 75 ); /* taken from cf2font.c */ + stem_width_per_1000 = stem_width; + } + else { - AF_StyleMetrics metrics; - FT_UInt options = AF_STYLE_NONE_DFLT; + stem_width = af_intToFixed( standard_width ); + stem_width_per_1000 = FT_MulFix( stem_width, em_ratio ); + } + log_base_2 = FT_MSB( (FT_UInt32)stem_width_per_1000 ) + + FT_MSB( (FT_UInt32)ppem ); -#ifdef FT_OPTION_AUTOFIT2 - /* XXX: undocumented hook to activate the latin2 writing system */ - if ( load_flags & ( 1UL << 20 ) ) - options = AF_STYLE_LTN2_DFLT; -#endif + if ( log_base_2 >= 46 ) + { + /* possible overflow */ + scaled_stem = af_intToFixed( x4 ); + } + else + scaled_stem = FT_MulFix( stem_width_per_1000, ppem ); - error = af_face_globals_get_metrics( loader->globals, gindex, - options, &metrics ); - if ( !error ) + /* now apply the darkening parameters */ + if ( scaled_stem < af_intToFixed( x1 ) ) + darken_amount = FT_DivFix( af_intToFixed( y1 ), ppem ); + + else if ( scaled_stem < af_intToFixed( x2 ) ) + { + FT_Int xdelta = x2 - x1; + FT_Int ydelta = y2 - y1; + FT_Int x = stem_width_per_1000 - + FT_DivFix( af_intToFixed( x1 ), ppem ); + + + if ( !xdelta ) + goto Try_x3; + + darken_amount = FT_MulDiv( x, ydelta, xdelta ) + + FT_DivFix( af_intToFixed( y1 ), ppem ); + } + + else if ( scaled_stem < af_intToFixed( x3 ) ) + { + Try_x3: { -#ifdef FT_CONFIG_OPTION_PIC - AF_FaceGlobals globals = loader->globals; -#endif - AF_StyleClass style_class = metrics->style_class; - AF_WritingSystemClass writing_system_class = - AF_WRITING_SYSTEM_CLASSES_GET[style_class->writing_system]; + FT_Int xdelta = x3 - x2; + FT_Int ydelta = y3 - y2; + FT_Int x = stem_width_per_1000 - + FT_DivFix( af_intToFixed( x2 ), ppem ); - loader->metrics = metrics; + if ( !xdelta ) + goto Try_x4; - if ( writing_system_class->style_metrics_scale ) - writing_system_class->style_metrics_scale( metrics, &scaler ); - else - metrics->scaler = scaler; + darken_amount = FT_MulDiv( x, ydelta, xdelta ) + + FT_DivFix( af_intToFixed( y2 ), ppem ); + } + } - load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_IGNORE_TRANSFORM; - load_flags &= ~FT_LOAD_RENDER; + else if ( scaled_stem < af_intToFixed( x4 ) ) + { + Try_x4: + { + FT_Int xdelta = x4 - x3; + FT_Int ydelta = y4 - y3; + FT_Int x = stem_width_per_1000 - + FT_DivFix( af_intToFixed( x3 ), ppem ); - if ( writing_system_class->style_hints_init ) - { - error = writing_system_class->style_hints_init( loader->hints, - metrics ); - if ( error ) - goto Exit; - } - error = af_loader_load_g( loader, &scaler, gindex, load_flags ); + if ( !xdelta ) + goto Use_y4; + + darken_amount = FT_MulDiv( x, ydelta, xdelta ) + + FT_DivFix( af_intToFixed( y3 ), ppem ); } } - Exit: - return error; + + else + { + Use_y4: + darken_amount = FT_DivFix( af_intToFixed( y4 ), ppem ); + } + + /* Convert darken_amount from per 1000 em to true character space. */ + return af_fixedToInt( FT_DivFix( darken_amount, em_ratio ) ); } |