diff options
Diffstat (limited to '0008-sfnt-Add-API-for-retrieving-a-COLR-v1-ClipBox-table.patch')
| -rw-r--r-- | 0008-sfnt-Add-API-for-retrieving-a-COLR-v1-ClipBox-table.patch | 474 |
1 files changed, 474 insertions, 0 deletions
diff --git a/0008-sfnt-Add-API-for-retrieving-a-COLR-v1-ClipBox-table.patch b/0008-sfnt-Add-API-for-retrieving-a-COLR-v1-ClipBox-table.patch new file mode 100644 index 000000000000..be0ad6973a09 --- /dev/null +++ b/0008-sfnt-Add-API-for-retrieving-a-COLR-v1-ClipBox-table.patch @@ -0,0 +1,474 @@ +From 47cf8ebf4a78ed42da455a98d77a92ce6a180d78 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Dominik=20R=C3=B6ttsches?= <drott@chromium.org> +Date: Wed, 28 Jul 2021 17:36:57 +0300 +Subject: [PATCH] [sfnt] Add API for retrieving a 'COLR' v1 'ClipBox' table. + +The optional 'COLR' v1 glyph-specific clip box helps upstream graphics +libraries allocate a sufficiently large bitmap for a glyph without having to +traverse the glyph graph for that. See + + https://github.com/googlefonts/colr-gradients-spec/issues/251 + +for background on the introduction of this specification change. + +* include/freetype/ftcolor.h (FT_ClipBox): New structure. +(FT_Get_Color_Glyph_ClipBox): New function declaration. + +* include/freetype/internal/sfnt.h (TT_Get_Color_Glyph_ClipBox_Func): +New function type. +(SFNT_Interface, FT_DEFINE_SFNT_INTERFACE): Use it. + +* src/base/ftobjs.c (FT_Get_Color_Glyph_ClipBox): New function to link API +with SFNT implementation. + +* src/sfnt/sfdriver.c (sfnt_interface): Updated. +* src/sfnt/ttcolr.c (Colr): New field `clip_list`. +(tt_face_load_colr): Parse global clip list offset. +(tt_face_get_color_glyph_clipbox): New function to find the clip box for a +glyph id from the clip list array. +* src/sfnt/ttcolr.h: Updated. +--- + include/freetype/ftcolor.h | 86 +++++++++++++++++++++ + include/freetype/internal/sfnt.h | 63 +++++++++++++--- + src/base/ftobjs.c | 29 +++++++ + src/sfnt/sfdriver.c | 10 ++- + src/sfnt/ttcolr.c | 125 ++++++++++++++++++++++++++++++- + src/sfnt/ttcolr.h | 5 ++ + 6 files changed, 302 insertions(+), 16 deletions(-) + +diff --git a/include/freetype/ftcolor.h b/include/freetype/ftcolor.h +index a4bd62a26..b98289917 100644 +--- a/include/freetype/ftcolor.h ++++ b/include/freetype/ftcolor.h +@@ -1383,6 +1383,49 @@ FT_BEGIN_HEADER + } FT_Color_Root_Transform; + + ++ /************************************************************************** ++ * ++ * @struct: ++ * FT_ClipBox ++ * ++ * @description: ++ * A structure representing a 'COLR' v1 'ClipBox' table. 'COLR' v1 ++ * glyphs may optionally define a clip box for aiding allocation or ++ * defining a maximum drawable region. Use @FT_Get_Color_Glyph_ClipBox ++ * to retrieve it. ++ * ++ * @fields: ++ * bottom_left :: ++ * The bottom left corner of the clip box as an @FT_Vector with ++ * fixed-point coordinates in 26.6 format. ++ * ++ * top_left :: ++ * The top left corner of the clip box as an @FT_Vector with ++ * fixed-point coordinates in 26.6 format. ++ * ++ * top_right :: ++ * The top right corner of the clip box as an @FT_Vector with ++ * fixed-point coordinates in 26.6 format. ++ * ++ * bottom_right :: ++ * The bottom right corner of the clip box as an @FT_Vector with ++ * fixed-point coordinates in 26.6 format. ++ * ++ * @since: ++ * 2.12 -- **currently experimental only!** There might be changes ++ * without retaining backward compatibility of both the API and ABI. ++ * ++ */ ++ typedef struct FT_ClipBox_ ++ { ++ FT_Vector bottom_left; ++ FT_Vector top_left; ++ FT_Vector top_right; ++ FT_Vector bottom_right; ++ ++ } FT_ClipBox; ++ ++ + /************************************************************************** + * + * @function: +@@ -1475,6 +1518,49 @@ FT_BEGIN_HEADER + FT_OpaquePaint* paint ); + + ++ /************************************************************************** ++ * ++ * @function: ++ * FT_Get_Color_Glyph_ClipBox ++ * ++ * @description: ++ * Search for a 'COLR' v1 clip box for the specified `base_glyph` and ++ * fill the `clip_box` parameter with the 'COLR' v1 'ClipBox' information ++ * if one is found. ++ * ++ * @input: ++ * face :: ++ * A handle to the parent face object. ++ * ++ * base_glyph :: ++ * The glyph index for which to retrieve the clip box. ++ * ++ * @output: ++ * clip_box :: ++ * The clip box for the requested `base_glyph` if one is found. The ++ * clip box is computed taking scale and transformations configured on ++ * the @FT_Face into account. @FT_ClipBox contains @FT_Vector values ++ * in 26.6 format. ++ * ++ * @return: ++ * Value~1 if a clip box is found. If no clip box is found or an error ++ * occured, value~0 is returned. ++ * ++ * @note: ++ * To retrieve the clip box in font units, reset scale to units-per-em ++ * and remove transforms configured using @FT_Set_Transform. ++ * ++ * @since: ++ * 2.12 -- **currently experimental only!** There might be changes ++ * without retaining backward compatibility of both the API and ABI. ++ * ++ */ ++ FT_EXPORT( FT_Bool ) ++ FT_Get_Color_Glyph_ClipBox( FT_Face face, ++ FT_UInt base_glyph, ++ FT_ClipBox* clip_box ); ++ ++ + /************************************************************************** + * + * @function: +diff --git a/include/freetype/internal/sfnt.h b/include/freetype/internal/sfnt.h +index 438ec897e..e8d77e232 100644 +--- a/include/freetype/internal/sfnt.h ++++ b/include/freetype/internal/sfnt.h +@@ -555,6 +555,44 @@ FT_BEGIN_HEADER + FT_OpaquePaint *paint ); + + ++ /************************************************************************** ++ * ++ * @functype: ++ * TT_Get_Color_Glyph_ClipBox_Func ++ * ++ * @description: ++ * Search for a 'COLR' v1 clip box for the specified `base_glyph` and ++ * fill the `clip_box` parameter with the 'COLR' v1 'ClipBox' information ++ * if one is found. ++ * ++ * @input: ++ * face :: ++ * A handle to the parent face object. ++ * ++ * base_glyph :: ++ * The glyph index for which to retrieve the clip box. ++ * ++ * @output: ++ * clip_box :: ++ * The clip box for the requested base_glyph if one is found. The clip ++ * box is computed taking scale and transformations configured on the ++ * @FT_Face into account. @FT_ClipBox contains @FT_Vector values in ++ * 26.6 format. ++ * ++ * @note: ++ * To retrieve the clip box in font units, reset scale to units-per-em ++ * and remove transforms configured using @FT_Set_Transform. ++ * ++ * @return: ++ * Value~1 if a ClipBox is found. If no clip box is found or an ++ * error occured, value~0 is returned. ++ */ ++ typedef FT_Bool ++ ( *TT_Get_Color_Glyph_ClipBox_Func )( TT_Face face, ++ FT_UInt base_glyph, ++ FT_ClipBox* clip_box ); ++ ++ + /************************************************************************** + * + * @functype: +@@ -890,17 +928,18 @@ FT_BEGIN_HEADER + TT_Set_SBit_Strike_Func set_sbit_strike; + TT_Load_Strike_Metrics_Func load_strike_metrics; + +- TT_Load_Table_Func load_cpal; +- TT_Load_Table_Func load_colr; +- TT_Free_Table_Func free_cpal; +- TT_Free_Table_Func free_colr; +- TT_Set_Palette_Func set_palette; +- TT_Get_Colr_Layer_Func get_colr_layer; +- TT_Get_Color_Glyph_Paint_Func get_colr_glyph_paint; +- TT_Get_Paint_Layers_Func get_paint_layers; +- TT_Get_Colorline_Stops_Func get_colorline_stops; +- TT_Get_Paint_Func get_paint; +- TT_Blend_Colr_Func colr_blend; ++ TT_Load_Table_Func load_cpal; ++ TT_Load_Table_Func load_colr; ++ TT_Free_Table_Func free_cpal; ++ TT_Free_Table_Func free_colr; ++ TT_Set_Palette_Func set_palette; ++ TT_Get_Colr_Layer_Func get_colr_layer; ++ TT_Get_Color_Glyph_Paint_Func get_colr_glyph_paint; ++ TT_Get_Color_Glyph_ClipBox_Func get_color_glyph_clipbox; ++ TT_Get_Paint_Layers_Func get_paint_layers; ++ TT_Get_Colorline_Stops_Func get_colorline_stops; ++ TT_Get_Paint_Func get_paint; ++ TT_Blend_Colr_Func colr_blend; + + TT_Get_Metrics_Func get_metrics; + +@@ -951,6 +990,7 @@ FT_BEGIN_HEADER + set_palette_, \ + get_colr_layer_, \ + get_colr_glyph_paint_, \ ++ get_color_glyph_clipbox, \ + get_paint_layers_, \ + get_colorline_stops_, \ + get_paint_, \ +@@ -995,6 +1035,7 @@ FT_BEGIN_HEADER + set_palette_, \ + get_colr_layer_, \ + get_colr_glyph_paint_, \ ++ get_color_glyph_clipbox, \ + get_paint_layers_, \ + get_colorline_stops_, \ + get_paint_, \ +diff --git a/src/base/ftobjs.c b/src/base/ftobjs.c +index 0ded2440f..5c1a4d034 100644 +--- a/src/base/ftobjs.c ++++ b/src/base/ftobjs.c +@@ -5639,6 +5639,35 @@ + } + + ++ /* documentation is in ftcolor.h */ ++ ++ FT_EXPORT_DEF( FT_Bool ) ++ FT_Get_Color_Glyph_ClipBox( FT_Face face, ++ FT_UInt base_glyph, ++ FT_ClipBox* clip_box ) ++ { ++ TT_Face ttface; ++ SFNT_Service sfnt; ++ ++ ++ if ( !face || !clip_box ) ++ return 0; ++ ++ if ( !FT_IS_SFNT( face ) ) ++ return 0; ++ ++ ttface = (TT_Face)face; ++ sfnt = (SFNT_Service)ttface->sfnt; ++ ++ if ( sfnt->get_color_glyph_clipbox ) ++ return sfnt->get_color_glyph_clipbox( ttface, ++ base_glyph, ++ clip_box ); ++ else ++ return 0; ++ } ++ ++ + /* documentation is in freetype.h */ + + FT_EXPORT_DEF( FT_Bool ) +diff --git a/src/sfnt/sfdriver.c b/src/sfnt/sfdriver.c +index 824e709fa..d1d01c99e 100644 +--- a/src/sfnt/sfdriver.c ++++ b/src/sfnt/sfdriver.c +@@ -1292,13 +1292,15 @@ + /* TT_Get_Colr_Layer_Func get_colr_layer */ + + PUT_COLOR_LAYERS_V1( tt_face_get_colr_glyph_paint ), +- /* TT_Get_Colr_Glyph_Paint_Func get_colr_glyph_paint */ ++ /* TT_Get_Color_Glyph_Paint_Func get_colr_glyph_paint */ ++ PUT_COLOR_LAYERS_V1( tt_face_get_color_glyph_clipbox ), ++ /* TT_Get_Color_Glyph_ClipBox_Func get_clipbox */ + PUT_COLOR_LAYERS_V1( tt_face_get_paint_layers ), +- /* TT_Get_Paint_Layers_Func get_paint_layers */ ++ /* TT_Get_Paint_Layers_Func get_paint_layers */ + PUT_COLOR_LAYERS_V1( tt_face_get_colorline_stops ), +- /* TT_Get_Paint get_paint */ ++ /* TT_Get_Paint get_paint */ + PUT_COLOR_LAYERS_V1( tt_face_get_paint ), +- /* TT_Get_Colorline_Stops_Func get_colorline_stops */ ++ /* TT_Get_Colorline_Stops_Func get_colorline_stops */ + + PUT_COLOR_LAYERS( tt_face_colr_blend_layer ), + /* TT_Blend_Colr_Func colr_blend */ +diff --git a/src/sfnt/ttcolr.c b/src/sfnt/ttcolr.c +index b8f4777ed..2f3e8846d 100644 +--- a/src/sfnt/ttcolr.c ++++ b/src/sfnt/ttcolr.c +@@ -94,6 +94,8 @@ + FT_ULong num_layers_v1; + FT_Byte* layers_v1; + ++ FT_Byte* clip_list; ++ + /* + * Paint tables start at the minimum of the end of the LayerList and the + * end of the BaseGlyphList. Record this location in a field here for +@@ -134,7 +136,7 @@ + + FT_ULong base_glyph_offset, layer_offset; + FT_ULong base_glyphs_offset_v1, num_base_glyphs_v1; +- FT_ULong layer_offset_v1, num_layers_v1; ++ FT_ULong layer_offset_v1, num_layers_v1, clip_list_offset; + FT_ULong table_size; + + +@@ -226,6 +228,16 @@ + colr->base_glyphs_v1 + + colr->num_base_glyphs_v1 * BASE_GLYPH_PAINT_RECORD_SIZE; + } ++ ++ clip_list_offset = FT_NEXT_ULONG( p ); ++ ++ if ( clip_list_offset >= table_size ) ++ goto InvalidTable; ++ ++ if ( clip_list_offset ) ++ colr->clip_list = (FT_Byte*)( table + clip_list_offset ); ++ else ++ colr->clip_list = 0; + } + + colr->base_glyphs = (FT_Byte*)( table + base_glyph_offset ); +@@ -796,6 +808,117 @@ + } + + ++ FT_LOCAL_DEF( FT_Bool ) ++ tt_face_get_color_glyph_clipbox( TT_Face face, ++ FT_UInt base_glyph, ++ FT_ClipBox* clip_box ) ++ { ++ Colr* colr; ++ ++ FT_Byte *p, *p1, *clip_base; ++ ++ FT_Byte clip_list_format; ++ FT_ULong num_clip_boxes, i; ++ FT_UShort gid_start, gid_end; ++ FT_UInt32 clip_box_offset; ++ FT_Byte format; ++ ++ const FT_Byte num_corners = 4; ++ FT_Vector corners[4]; ++ FT_Byte j; ++ FT_BBox font_clip_box; ++ ++ ++ colr = (Colr*)face->colr; ++ if ( !colr ) ++ return 0; ++ ++ if ( !colr->clip_list ) ++ return 0; ++ ++ p = colr->clip_list; ++ ++ clip_base = p; ++ clip_list_format = FT_NEXT_BYTE ( p ); ++ ++ /* Format byte used here to be able to upgrade ClipList for >16bit */ ++ /* glyph ids; for now we can expect it to be 0. */ ++ if ( !( clip_list_format == 0 ) ) ++ return 0; ++ ++ num_clip_boxes = FT_NEXT_ULONG( p ); ++ ++ for ( i = 0; i < num_clip_boxes; ++i ) ++ { ++ gid_start = FT_NEXT_USHORT( p ); ++ gid_end = FT_NEXT_USHORT( p ); ++ clip_box_offset = FT_NEXT_UOFF3( p ); ++ ++ if ( base_glyph >= gid_start && base_glyph <= gid_end ) ++ { ++ p1 = (FT_Byte*)( clip_base + clip_box_offset ); ++ ++ if ( p1 >= ( (FT_Byte*)colr->table + colr->table_size ) ) ++ return 0; ++ ++ format = FT_NEXT_BYTE( p1 ); ++ ++ if ( format < 0 || format > 1 ) ++ return 0; ++ ++ /* `face->root.size->metrics.x_scale` and `y_scale` are factors */ ++ /* that scale a font unit value in integers to a 26.6 fixed value */ ++ /* according to the requested size, see for example */ ++ /* `ft_recompute_scaled_metrics`. */ ++ font_clip_box.xMin = FT_MulFix( FT_NEXT_SHORT( p1 ), ++ face->root.size->metrics.x_scale ); ++ font_clip_box.yMin = FT_MulFix( FT_NEXT_SHORT( p1 ), ++ face->root.size->metrics.x_scale ); ++ font_clip_box.xMax = FT_MulFix( FT_NEXT_SHORT( p1 ), ++ face->root.size->metrics.x_scale ); ++ font_clip_box.yMax = FT_MulFix( FT_NEXT_SHORT( p1 ), ++ face->root.size->metrics.x_scale ); ++ ++ /* Make 4 corner points (xMin, yMin), (xMax, yMax) and transform */ ++ /* them. If we we would only transform two corner points and */ ++ /* span a rectangle based on those, the rectangle may become too */ ++ /* small to cover the glyph. */ ++ corners[0].x = font_clip_box.xMin; ++ corners[1].x = font_clip_box.xMin; ++ corners[2].x = font_clip_box.xMax; ++ corners[3].x = font_clip_box.xMax; ++ ++ corners[0].y = font_clip_box.yMin; ++ corners[1].y = font_clip_box.yMax; ++ corners[2].y = font_clip_box.yMax; ++ corners[3].y = font_clip_box.yMin; ++ ++ for ( j = 0; j < num_corners; ++j ) ++ { ++ if ( face->root.internal->transform_flags & 1 ) ++ FT_Vector_Transform( &corners[j], ++ &face->root.internal->transform_matrix ); ++ ++ if ( face->root.internal->transform_flags & 2 ) ++ { ++ corners[j].x += face->root.internal->transform_delta.x; ++ corners[j].y += face->root.internal->transform_delta.y; ++ } ++ } ++ ++ clip_box->bottom_left = corners[0]; ++ clip_box->top_left = corners[1]; ++ clip_box->top_right = corners[2]; ++ clip_box->bottom_right = corners[3]; ++ ++ return 1; ++ } ++ } ++ ++ return 0; ++ } ++ ++ + FT_LOCAL_DEF( FT_Bool ) + tt_face_get_paint_layers( TT_Face face, + FT_LayerIterator* iterator, +diff --git a/src/sfnt/ttcolr.h b/src/sfnt/ttcolr.h +index c91d2b172..b81e4cb95 100644 +--- a/src/sfnt/ttcolr.h ++++ b/src/sfnt/ttcolr.h +@@ -48,6 +48,11 @@ FT_BEGIN_HEADER + FT_Color_Root_Transform root_transform, + FT_OpaquePaint* paint ); + ++ FT_LOCAL( FT_Bool ) ++ tt_face_get_color_glyph_clipbox( TT_Face face, ++ FT_UInt base_glyph, ++ FT_ClipBox* clip_box ); ++ + FT_LOCAL( FT_Bool ) + tt_face_get_paint_layers( TT_Face face, + FT_LayerIterator* iterator, |