ref: f04d81751ac68b23c89da2edd31c43fd9fc5c75c
parent: 84eebf48021ab76c1c628bb7451b712f701e4518
author: Shao Yu Zhang <shaozhang@fb.com>
date: Sat May 12 23:25:09 EDT 2018
[sfnt] Preliminary support of coloured layer outlines. 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.