* 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.
* include/freetype/freetype.h (FT_Get_Color_Glyph_Paint): New method
for retrieving the root paint object for a color glyph by specifying
a glyph ID.
(FT_Get_Paint_Layers): New method for retrieving the layers of a
`PaintColorGlyph`.
(FT_Get_ColorLine_Stops): New method for retrieving the stops of a
color.
(FT_Get_Paint): New method for resolving an `FT_OpaquePaint` into an
`FT_COLR_Paint` object.
* include/freetype/freetype.h (FT_PaintFormat, FT_ColorStopIterator,
FT_ColorIndex, FT_ColorStop, FT_PaintExtend, FT_ColorLine,
FT_Affine23, FT_CompositeMode, FT_OpaquePaint, FT_PaintColrLayers,
FT_PaintSolid, FT_PaintLinearGradient, FT_PaintRadialGradient,
FT_PaintGlyph, FT_PaintColrGlyph, FT_PaintTransformed,
FT_PaintTranslate, FT_PaintRotate, FT_PaintSkew, FT_PaintComposite,
FT_COLR_Paint): Adding structs and enum to represent paint format,
color stop information, gradient extend information, structs to
reference paint offsets, and to define transforms and compositions.
Adding a union type to represent the union of the structs,
distinguished by `FT_PaintFormat`.
* include/freetype/config/ftmodule.h: Add both the 'sfd' and 'bsfd'
renderers to the list of modules.
* CMakeLists.txt (BASE_SRCS): Add 'sdf' single-object module.
* src/sdf/module.mk, src/sfd/rules.mk: New files.
* src/sdf/ftsdf.h (ft_sdf_raster): New forward declaration.
* include/freetype/ftmoderr.h (FT_MODERRDEF): Add error definition
for the 'sdf' module.
* include/freetype/internal/fttrace.h (FT_TRACE_DEF): Add trace
definition for the `sdf' module.
* modules.cfg (RASTER_MODULES): Add the `sdf' module to the list of
rasterizers.
* src/sdf/ftsdf.c (sdf_generate_bounding_box): New function, which
is an optimized version of `sdf_generate`.
(sdf_generate_subdivision): New function.
* src/sdf/ftsdf.c (sdf_generate): New function, currently disabled.
This is a proof-of-concept implementation: It doesn't use any
optimization, it simply checks all grid points against all contours.
* src/sdf/ftsdf.c (get_min_distance_line, get_min_distance_conic,
get_min_distance_cubic): New functions. Note that
`get_min_distance_conic` comes with two implementations (using an
analytical and an iterative method, to be controlled with the
`USE_NEWTON_FOR_CONIC` macro).
* src/sdf/ftsdf.c (FT_DEBUG_INNER, FT_ASSIGNP_INNER)
[FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New macros.
(SDF_MemoryUser) [FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New
struct for memory usage tracing.
(sdf_alloc, sdf_free) [FT_DEBUG_LEVEL_TRACE && FT_DEBUG_MEMORY]: New
functions for memory usage tracing.
(SDF_ALLOC, SDF_FREE): New macros for memory management.
(SDF_MEMORY_TRACKER_DECLARE, SDF_MEMORY_TRACKER_SETUP,
SDF_MEMORY_TRACKER_DONE): New macros to set up memory usage tracing.
(USE_NEWTON_FOR_CONIC, MAX_NEWTON_DIVISIONS, MAX_NEWTON_STEPS,
CORNER_CHECK_EPSILON, CG_DIMEN): New configuration macros for
controlling the process of finding the shortest distance.
(MUL_26D6, VEC_26D6_DOT): New auxiliary macros.
(SDF_TRaster, SDF_Edge, SDF_Contour, SDF_Shape, SDF_Signed_Distance,
SDF_Params): New structs for setting up SDF data.
(SDF_Edge_Type, SDF_Contour_Orientation): New enums for SDF data.
(zero_vector, null_edge, null_contour, null_shape, max_sdf): Useful
constants.
(sdf_edge_new, sdf_edge_done, sdf_contour_new, sdf_contour_done,
sdf_shape_new, sdf_shape_done): New constructors and destructors.
Dominik Röttsches