ref: cdad4db4240044512a33cf480f28b093ae3a85c9
parent: 9e422b67c8f1a2e06cb934c2867e0536729793f4
author: Dominik Röttsches <drott@chromium.org>
date: Wed Dec 16 11:52:24 EST 2020
[sfnt] Add API to get actual paint from `FT_OpaquePaint` (#59703). * 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.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,23 @@
2020-12-16 Dominik Röttsches <drott@chromium.org>
+ [sfnt] Add API to get actual paint from `FT_OpaquePaint` (#59703).
+
+ * 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.
+
+2020-12-16 Dominik Röttsches <drott@chromium.org>
+
[sfnt] Add API to retrieve 'COLR' v1 root paint (#59703).
* src/sfnt/ttcolr.c (BaseGlyphV1Record): New structure.
--- a/src/sfnt/ttcolr.c
+++ b/src/sfnt/ttcolr.c
@@ -320,6 +320,301 @@
static FT_Bool
+ read_color_line( FT_Byte* paint_base,
+ FT_ULong colorline_offset,
+ FT_ColorLine *colorline )
+ {+ FT_Byte* p = (FT_Byte *)( paint_base + colorline_offset );
+ FT_PaintExtend paint_extend;
+ /* TODO: Check pointer limits. */
+
+
+ paint_extend = FT_NEXT_BYTE( p );
+ if ( paint_extend > FT_COLR_PAINT_EXTEND_REFLECT )
+ return 0;
+
+ colorline->extend = paint_extend;
+
+ colorline->color_stop_iterator.num_color_stops = FT_NEXT_USHORT( p );
+ colorline->color_stop_iterator.p = p;
+ colorline->color_stop_iterator.current_color_stop = 0;
+
+ return 1;
+ }
+
+
+ static FT_Bool
+ read_paint( Colr* colr,
+ FT_Byte* p,
+ FT_COLR_Paint* apaint )
+ {+ FT_Byte* paint_base = p;
+
+
+ apaint->format = FT_NEXT_BYTE( p );
+
+ if ( apaint->format >= FT_COLR_PAINT_FORMAT_MAX )
+ return 0;
+
+ if ( apaint->format == FT_COLR_PAINTFORMAT_COLR_LAYERS )
+ {+ /* Initialize layer iterator/ */
+ FT_Byte num_layers;
+ FT_UInt32 first_layer_index;
+
+
+ num_layers = FT_NEXT_BYTE( p );
+ if ( num_layers > colr->num_layers_v1 )
+ return 0;
+
+ first_layer_index = FT_NEXT_ULONG( p );
+ if ( first_layer_index + num_layers > colr->num_layers_v1 )
+ return 0;
+
+ apaint->u.colr_layers.layer_iterator.num_layers = num_layers;
+ apaint->u.colr_layers.layer_iterator.layer = 0;
+ /* TODO: Check whether pointer is outside colr? */
+ apaint->u.colr_layers.layer_iterator.p =
+ colr->layers_v1 +
+ LAYER_V1_LIST_NUM_LAYERS_SIZE +
+ LAYER_V1_LIST_PAINT_OFFSET_SIZE * first_layer_index;
+
+ return 1;
+ }
+
+ if ( apaint->format == FT_COLR_PAINTFORMAT_GLYPH )
+ {+ FT_UInt32 paint_offset;
+ FT_Byte* paint_p;
+
+
+ paint_offset = FT_NEXT_UOFF3( p );
+ if ( !paint_offset )
+ return 0;
+
+ paint_p = (FT_Byte*)( paint_base + paint_offset );
+ if ( paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.glyph.paint.p = paint_p;
+ apaint->u.glyph.glyphID = FT_NEXT_USHORT( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_SOLID )
+ {+ apaint->u.solid.color.palette_index = FT_NEXT_USHORT ( p );
+ apaint->u.solid.color.alpha = FT_NEXT_USHORT ( p );
+ /* skip VarIdx */
+ FT_NEXT_ULONG ( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_LINEAR_GRADIENT )
+ {+ FT_ULong color_line_offset = FT_NEXT_OFF3( p );
+
+
+ if ( !read_color_line( paint_base,
+ color_line_offset,
+ &apaint->u.linear_gradient.colorline ) )
+ return 0;
+
+ /* skip VarIdx entries */
+ apaint->u.linear_gradient.p0.x = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.linear_gradient.p0.y = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.linear_gradient.p1.x = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.linear_gradient.p1.y = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.linear_gradient.p2.x = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.linear_gradient.p2.y = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_RADIAL_GRADIENT )
+ {+ FT_ULong color_line_offset = color_line_offset = FT_NEXT_OFF3( p );
+
+
+ if ( !read_color_line( paint_base,
+ color_line_offset,
+ &apaint->u.linear_gradient.colorline ) )
+ return 0;
+
+ /* skip VarIdx entries */
+ apaint->u.radial_gradient.c0.x = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.radial_gradient.c0.y = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+
+ apaint->u.radial_gradient.r0 = FT_NEXT_USHORT ( p );
+ FT_NEXT_ULONG ( p );
+
+ apaint->u.radial_gradient.c1.x = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+ apaint->u.radial_gradient.c1.y = FT_NEXT_SHORT ( p );
+ FT_NEXT_ULONG ( p );
+
+ apaint->u.radial_gradient.r1 = FT_NEXT_USHORT ( p );
+ FT_NEXT_ULONG ( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_TRANSFORMED )
+ {+ FT_UInt32 paint_offset;
+ FT_Byte* paint_p;
+
+
+ paint_offset = FT_NEXT_UOFF3( p );
+ if ( !paint_offset )
+ return 0;
+
+ paint_p = (FT_Byte*)( paint_base + paint_offset );
+ if ( paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.transformed.paint.p = paint_p;
+
+ /* skip VarIdx entries */
+ apaint->u.transformed.affine.xx = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.transformed.affine.yx = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.transformed.affine.xy = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.transformed.affine.yy = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.transformed.affine.dx = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.transformed.affine.dy = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_TRANSLATE )
+ {+ FT_UInt32 paint_offset;
+ FT_Byte* paint_p;
+
+
+ paint_offset = FT_NEXT_UOFF3( p );
+ if ( !paint_offset )
+ return 0;
+
+ paint_p = (FT_Byte*)( paint_base + paint_offset );
+ if ( paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.translate.paint.p = paint_p;
+
+ /* skip VarIdx entries */
+ apaint->u.translate.dx = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.translate.dy = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_ROTATE )
+ {+ FT_UInt32 paint_offset;
+ FT_Byte* paint_p;
+
+
+ paint_offset = FT_NEXT_UOFF3( p );
+ if ( !paint_offset )
+ return 0;
+
+ paint_p = (FT_Byte*)( paint_base + paint_offset );
+ if ( paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.rotate.paint.p = paint_p;
+
+ /* skip VarIdx entries */
+ apaint->u.rotate.angle = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+
+ apaint->u.rotate.center_x = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.rotate.center_y = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_SKEW )
+ {+ FT_UInt32 paint_offset;
+ FT_Byte* paint_p;
+
+
+ paint_offset = FT_NEXT_UOFF3( p );
+ if ( !paint_offset )
+ return 0;
+
+ paint_p = (FT_Byte*)( paint_base + paint_offset );
+ if ( paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.skew.paint.p = paint_p;
+
+ /* skip VarIdx entries */
+ apaint->u.skew.x_skew_angle = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.skew.y_skew_angle = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+
+ apaint->u.skew.center_x = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ apaint->u.skew.center_y = FT_NEXT_LONG( p );
+ FT_NEXT_ULONG( p );
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_COMPOSITE )
+ {+ FT_UInt32 source_paint_offset;
+ FT_Byte* source_paint_p;
+
+ FT_UInt32 backdrop_paint_offset;
+ FT_Byte* backdrop_paint_p;
+
+ FT_UInt composite_mode;
+
+
+ source_paint_offset = FT_NEXT_UOFF3( p );
+ if ( !source_paint_offset )
+ return 0;
+
+ source_paint_p = (FT_Byte*)( paint_base + source_paint_offset );
+ if ( source_paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.composite.source_paint.p = source_paint_p;
+
+ composite_mode = FT_NEXT_BYTE( p );
+ if ( composite_mode >= FT_COLR_COMPOSITE_MAX )
+ return 0;
+
+ apaint->u.composite.composite_mode = composite_mode;
+
+ backdrop_paint_offset = FT_NEXT_UOFF3( p );
+ if ( !backdrop_paint_offset )
+ return 0;
+
+ backdrop_paint_p = (FT_Byte*)( paint_base + backdrop_paint_offset );
+ if ( backdrop_paint_p > ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ apaint->u.composite.backdrop_paint.p = backdrop_paint_p;
+ }
+
+ else if ( apaint->format == FT_COLR_PAINTFORMAT_COLR_GLYPH )
+ apaint->u.colr_glyph.glyphID = FT_NEXT_USHORT( p );
+
+ return 1;
+ }
+
+
+ static FT_Bool
find_base_glyph_v1_record ( FT_Byte * base_glyph_begin,
FT_Int num_base_glyph,
FT_UInt glyph_id,
@@ -395,6 +690,26 @@
opaque_paint->p = p;
return 1;
+ }
+
+
+ FT_LOCAL_DEF( FT_Bool )
+ tt_face_get_paint( TT_Face face,
+ FT_OpaquePaint opaque_paint,
+ FT_COLR_Paint* paint )
+ {+ Colr* colr = (Colr*)face->colr;
+
+ FT_Byte* p;
+
+
+ if ( opaque_paint.p < (FT_Byte*)colr->table ||
+ opaque_paint.p >= ( (FT_Byte*)colr->table + colr->table_size ) )
+ return 0;
+
+ p = opaque_paint.p;
+
+ return read_paint( colr, p, paint );
}
--- a/src/sfnt/ttcolr.h
+++ b/src/sfnt/ttcolr.h
@@ -47,6 +47,11 @@
FT_UInt base_glyph,
FT_OpaquePaint* paint );
+ FT_LOCAL( FT_Bool )
+ tt_face_get_paint( TT_Face face,
+ FT_OpaquePaint opaque_paint,
+ FT_COLR_Paint* paint );
+
FT_LOCAL( FT_Error )
tt_face_colr_blend_layer( TT_Face face,
FT_UInt color_index,