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/freetype.h (FT_Get_Color_Glyph_Paint):
Additional function argument root_transform to control whether
root transform should be returned.
(FT_OpaquePaint): Additional tracking field to denote whether
root transform is to be returned.
* include/freetype/internal/sfnt.h
(TT_Get_Color_Glyph_Paint_Func): Propagate additional argument.
* src/base/ftobjs.c (FT_Get_Color_Glyph_Paint): Ditto.
* src/sfnt/ttcolr.c (tt_face_get_colr_glyph_paint): Return root
transform reflecting the size and tranform configured on
FT_Face.
(read_paint): Initialize and track status of insert_root_transform
flag.
* src/sfnt/ttcolr.c (tt_face_get_paint_layers): New function to get
the layers of a `PaintColrLayers` table in the font, using an
`FT_LayerIterator` from an `FT_PaintColrLayers` object retrieved via
`tt_face_get_paint`.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (tt_face_get_colorline_stops): New function to
return the current `FT_ColorStop` object from `FT_ColorStopIterator`.
Also increment the iterator.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (tt_face_get_paint): New function to resolve an
`FT_OpaquePaint` paint reference into an `FT_COLR_Paint` object of a
certain format, which contains the detailed information stored in a
paint of the respective format.
(read_paint): New function to provide the format specific parsing
and to populate the data members of each specific `FT_COLR_Paint`
subtype.
(read_color_line): New function to parse retrieved color line
information into an `FT_ColorLine` object, which has information
about the color line extend mode as well as an
`FT_ColorStopIterator` object.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/ttcolr.c (BaseGlyphV1Record): New structure.
(tt_face_load_colr): Handle version 1 table header.
(find_base_glyph_v1_record): New auxiliary function.
(tt_face_get_colr_glyph_paint): New function to find the root
`FT_OpaquePaint` object for a given glyph ID.
* src/sfnt/ttcolr.h: Updated.
This solution doesn't store any data in an `FT_GlyphSlot' object.
* include/freetype/freetype.h (FT_LayerIterator): New structure.
(FT_Get_Color_Glyph_Layer): New function.
* include/freetype/internal/sfnt.h (TT_Get_Colr_Layer_Func): New
function type.
(SFNT_Interface, FT_DEFINE_SFNT_INTERFACE): Add it.
* src/base/ftobjs.c (FT_Get_Color_Glyph_Layer): Implement it.
* src/sfnt/ttcolr.c (tt_face_get_colr_layer): New function.
* src/sfnt/ttcolr.h: Updated.
* src/sfnt/sfdriver.c (sfnt_interface): Updated.
* src/sfnt/sfdriver.c: Include `ttcpal.h'.
* src/sfnt/sfnt.c: Include `ttcpal.c'.
* src/sfnt/ttcolr.c, src/sfnt/ttcolr.h: Move CPAL stuff to ...
* src/sfnt/ttcpal.c, src/sfnt/ttcpal.c: ... these new files.
* src/sfnt/Jamfile (_sources), src/sfnt/rules.mk (SFNT_DRV_SRC):
Updated.
* include/freetype/internal/fttrace.h: Add support for `colr' and
`cpal'.
Sort entries.
* src/sfnt/ttcolr.c (tt_face_palette_set): New function.
(tt_face_load_colr): Allocate `face->palette' and call
`tt_face_palette_set'.
Adjust return error code in case of error.
* src/sfnt/ttcolr.h: Updated.
* include/freetype/internal/sfnt.h (TT_Set_Palette_Func): New
function type.
(SFNT_Interface, FT_DEFINE_SFNT_INTERFACE): Add it.
* src/sfnt/sfdriver.c (sfnt_interface), src/sfnt/sfobjs.c
(sfnt_done_face): Updated.
This monster commit was created by applying Nikhil's scripts
`docconverter.py' and `markify.py' to all C header and source files,
followed up by minor manual clean-up.
No change in functionality, of course.
I used commit f7419907bc6044b9b7057f9789866426c804ba82 from
https://github.com/nikramakrishnan/freetype-docs.git.
* include/freetype/config/ftheader.h (FT_COLOR_H): New macro.
* include/freetype/internal/ftobjs.h (FT_Colr_Internal): Change
type of `load_flags' to `FT_Int32'.
* include/freetype/internal/sfnt.h (TT_Load_Colr_Layer_Func): Change
type of `idx' to `FT_UInt'.
(TT_Blend_Colr_Func): Change type of `color_index' to `FT_UInt'.
* src/base/ftobjs.c (FT_Render_Glyph_Internal): Change type of
`load_flags' to `FT_Int32'.
* src/sfnt/ttcolr.c (find_base_glyph_record,
tt_face_load_colr_layers): Change type of `glyph_id' to `FT_UInt'.
(tt_face_find_color, tt_face_colr_blend_layer): Change type of
`color_index' to `FT_UInt'.
Fix signedness and type issues.
* src/sfnt/ttcolr.h: Updated.
* include/freetype/internal/ftobjs.h (FT_Glyph_LayerRec): Move this
structure to...
* include/freetype/freetype.h (FT_Glyph_LayerRec): ... this
header file.
(FT_Glyph_Layer): New typedef.
Update code to use it where appropriate.
* src/base/ftobjs.c (FT_Get_GlyphLayers): New function.
This commit enables OpenType's COLR/CPAL table handling; a typical
application are color emojis that can be scaled to any size.
If the color palette does not exist or is invalid, the rendering
step rasterizes the outline instead. The current implementation
assumes that the foreground is black.
Enable this by defining option TT_CONFIG_OPTION_COLOR_LAYERS.
There are still some issues with metrics; additionally, an API to
fetch color layers is missing.
* devel/ftoption.h, include/freetype/config/ftoption.h
(TT_CONFIG_OPTION_COLOR_LAYERS): New macro.
* include/freetype/internal/ftobjs.h (FT_Glyph_LayerRec,
FT_Colr_InternalRec): New structures.
(FT_Slot_InternalRec): Add `color_layers' field.
* include/freetype/internal/sfnt.h (TT_Load_Colr_Layer_Func,
TT_Blend_Colr_Func): New function types.
(SFNT_Interface): Add `load_colr', `free_colr', `load_colr_layer',
and `colr_blend' fields.
* include/freetype/internal/tttypes.h (TT_FaceRec): Add
`colr_and_cpal' field.
* include/freetype/internal/tttags. (TTAG_COLR, TTAG_CPAL): New
macros.
* src/sfnt/ttcolr.c, src/sfnt/ttcolr.h: New files.
* src/base/ftobjs.c (ft_glyphslot_done, FT_Render_Glyph_Internal):
Handle glyph color layers.
* src/sfnt/Jamfile (_sources), src/sfnt/rules.mk (SFNT_DRV_SRC): Add
`ttcolr.c'.
* src/sfnt/sfdriver.c: Include `ttcolr.h'.
(PUT_COLOR_LAYERS): New macro.
Update call to `FT_DEFINE_SFNT_INTERFACE'.
* src/sfnt/sfnt.c: Include `ttcolr.c'.
* src/sfnt/sfobjs.c (sfnt_load_face): Load `COLR' and `CPAL' tables.
(sfnt_done_face): Updated.
* src/truetype/ttgload.c (TT_Load_Glyph): Handle color layers.
Dominik Röttsches