[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.
This commit is contained in:
Shao Yu Zhang 2018-05-13 03:25:09 +02:00 committed by Werner Lemberg
parent 84eebf4802
commit f04d81751a
17 changed files with 912 additions and 4 deletions

View File

@ -1,3 +1,57 @@
2018-05-13 Shao Yu Zhang <shaozhang@fb.com>
Werner Lemberg <wl@gnu.org>
[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.
2018-05-12 Arkady Shapkin <arkady.shapkin@gmail.com>
Use MS VC++'s _BitScanReverse to calculate MSB (patch #9636).

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@ -485,6 +485,15 @@ FT_BEGIN_HEADER
#define TT_CONFIG_OPTION_EMBEDDED_BITMAPS
/*************************************************************************/
/* */
/* Define TT_CONFIG_OPTION_COLOR_LAYERS if you want to support coloured */
/* outlines (from the COLR/CPAL tables) in all formats using the SFNT */
/* module (namely TrueType & OpenType). */
/* */
#define TT_CONFIG_OPTION_COLOR_LAYERS
/*************************************************************************/
/* */
/* Define TT_CONFIG_OPTION_POSTSCRIPT_NAMES if you want to be able to */

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@ -504,6 +504,15 @@ FT_BEGIN_HEADER
#define TT_CONFIG_OPTION_EMBEDDED_BITMAPS
/*************************************************************************/
/* */
/* Define TT_CONFIG_OPTION_COLOR_LAYERS if you want to support coloured */
/* outlines (from the COLR/CPAL tables) in all formats using the SFNT */
/* module (namely TrueType & OpenType). */
/* */
#define TT_CONFIG_OPTION_COLOR_LAYERS
/*************************************************************************/
/* */
/* Define TT_CONFIG_OPTION_POSTSCRIPT_NAMES if you want to be able to */

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@ -384,6 +384,23 @@ FT_BEGIN_HEADER
} FT_Face_InternalRec;
typedef struct FT_Glyph_LayerRec_
{
FT_UShort glyph_index;
FT_UShort color_index;
} FT_Glyph_LayerRec;
typedef struct FT_Colr_InternalRec_
{
FT_Glyph_LayerRec* layers;
FT_UShort num_layers;
FT_Int load_flags;
} FT_Colr_InternalRec, *FT_Colr_Internal;
/*************************************************************************/
/* */
/* <Struct> */
@ -417,6 +434,8 @@ FT_BEGIN_HEADER
/* */
/* glyph_hints :: Format-specific glyph hints management. */
/* */
/* color_layers :: Data from (SFNT) COLR/CPAL tables. */
/* */
#define FT_GLYPH_OWN_BITMAP 0x1U
@ -429,6 +448,8 @@ FT_BEGIN_HEADER
FT_Vector glyph_delta;
void* glyph_hints;
FT_Colr_Internal color_layers;
} FT_GlyphSlot_InternalRec;

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@ -428,6 +428,68 @@ FT_BEGIN_HEADER
FT_UShort* aadvance );
/*************************************************************************/
/* */
/* <FuncType> */
/* TT_Load_Colr_Layer_Func */
/* */
/* <Description> */
/* Load the color layer data given a glyph index. */
/* */
/* <Input> */
/* face :: The target face object. */
/* */
/* idx :: The glyph index. */
/* */
/* <Output> */
/* layers :: The layer info with color index and glyph index. */
/* Deallocate with `FT_FREE'. */
/* */
/* num_layers :: Number of layers. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. Returns an error if no */
/* color layer information exists for `idx'. */
/* */
typedef FT_Error
(*TT_Load_Colr_Layer_Func)( TT_Face face,
FT_Int idx,
FT_Glyph_LayerRec* *layers,
FT_UShort* num_layers );
/*************************************************************************/
/* */
/* <FuncType> */
/* TT_Blend_Colr_Func */
/* */
/* <Description> */
/* Blend the bitmap in `new_glyph' into `base_glyph' using the color */
/* specified by `color_index'. */
/* */
/* XXX: Handle foregound color */
/* */
/* <Input> */
/* face :: The target face object. */
/* */
/* color_index :: Color index from the COLR table. */
/* */
/* base_glyph :: Slot for bitmap to be merged into. The underlying */
/* bitmap may get reallocated. */
/* */
/* new_glyph :: Slot to be incooperated into `base_glyph'. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. Returns an error if */
/* color_index is invalid or reallocation fails. */
/* */
typedef FT_Error
(*TT_Blend_Colr_Func)( TT_Face face,
FT_Int color_index,
FT_GlyphSlot base_glyph,
FT_GlyphSlot new_glyph );
/*************************************************************************/
/* */
/* <FuncType> */
@ -616,6 +678,11 @@ FT_BEGIN_HEADER
TT_Set_SBit_Strike_Func set_sbit_strike;
TT_Load_Strike_Metrics_Func load_strike_metrics;
TT_Load_Table_Func load_colr;
TT_Free_Table_Func free_colr;
TT_Load_Colr_Layer_Func load_colr_layer;
TT_Blend_Colr_Func colr_blend;
TT_Get_Metrics_Func get_metrics;
TT_Get_Name_Func get_name;
@ -658,6 +725,10 @@ FT_BEGIN_HEADER
free_eblc_, \
set_sbit_strike_, \
load_strike_metrics_, \
load_colr_, \
free_colr_, \
load_colr_layer_, \
colr_blend_, \
get_metrics_, \
get_name_, \
get_name_id_ ) \
@ -691,6 +762,10 @@ FT_BEGIN_HEADER
free_eblc_, \
set_sbit_strike_, \
load_strike_metrics_, \
load_colr_, \
free_colr_, \
load_colr_layer_, \
colr_blend_, \
get_metrics_, \
get_name_, \
get_name_id_ \

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@ -1352,6 +1352,10 @@ FT_BEGIN_HEADER
/* exposed by the API and the indices used in */
/* the font's sbit table. */
/* */
/* colr_and_cpal :: A pointer to data related to `COLR' and */
/* `CPAL' tables. NULL if tables are not */
/* available. */
/* */
/* kern_table :: A pointer to the `kern' table. */
/* */
/* kern_table_size :: The size of the `kern' table. */
@ -1535,6 +1539,7 @@ FT_BEGIN_HEADER
FT_UInt sbit_num_strikes;
FT_UInt* sbit_strike_map;
void* colr_and_cpal;
FT_Byte* kern_table;
FT_ULong kern_table_size;
FT_UInt num_kern_tables;

View File

@ -46,6 +46,8 @@ FT_BEGIN_HEADER
#define TTAG_CFF2 FT_MAKE_TAG( 'C', 'F', 'F', '2' )
#define TTAG_CID FT_MAKE_TAG( 'C', 'I', 'D', ' ' )
#define TTAG_cmap FT_MAKE_TAG( 'c', 'm', 'a', 'p' )
#define TTAG_COLR FT_MAKE_TAG( 'C', 'O', 'L', 'R' )
#define TTAG_CPAL FT_MAKE_TAG( 'C', 'P', 'A', 'L' )
#define TTAG_cvar FT_MAKE_TAG( 'c', 'v', 'a', 'r' )
#define TTAG_cvt FT_MAKE_TAG( 'c', 'v', 't', ' ' )
#define TTAG_DSIG FT_MAKE_TAG( 'D', 'S', 'I', 'G' )

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@ -538,6 +538,16 @@
/* free bitmap buffer if needed */
ft_glyphslot_free_bitmap( slot );
/* free glyph color layers if needed */
if ( slot->internal->color_layers )
{
FT_Colr_InternalRec* color_layers = slot->internal->color_layers;
FT_FREE( color_layers->layers );
FT_FREE( slot->internal->color_layers );
}
/* slot->internal might be NULL in out-of-memory situations */
if ( slot->internal )
{
@ -4497,6 +4507,61 @@
break;
default:
if ( slot->internal->color_layers != NULL )
{
FT_Face face = slot->face;
error = FT_New_GlyphSlot( face, NULL );
if ( !error )
{
TT_Face ttface = (TT_Face)face;
SFNT_Service sfnt = (SFNT_Service)ttface->sfnt;
FT_Glyph_LayerRec* glyph_layers =
slot->internal->color_layers->layers;
FT_Int idx;
for ( idx = 0;
idx < slot->internal->color_layers->num_layers;
idx++ )
{
FT_Int load_flags;
load_flags = slot->internal->color_layers->load_flags
& ~FT_LOAD_COLOR;
load_flags |= FT_LOAD_RENDER;
error = FT_Load_Glyph( face,
glyph_layers[idx].glyph_index,
load_flags );
if ( error )
break;
error = sfnt->colr_blend( ttface,
glyph_layers[idx].color_index,
slot,
face->glyph );
if ( error )
break;
}
if ( !error )
slot->format = FT_GLYPH_FORMAT_BITMAP;
FT_Done_GlyphSlot( face->glyph );
}
if ( !error )
return error;
/* Failed to do the colored layer. Draw outline instead. */
slot->format = FT_GLYPH_FORMAT_OUTLINE;
}
{
FT_ListNode node = NULL;

View File

@ -27,6 +27,7 @@ SubDir FT2_TOP $(FT2_SRC_DIR) sfnt ;
ttmtx
ttpost
ttsbit
ttcolr
;
}
else

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@ -32,6 +32,7 @@ SFNT_DRV_SRC := $(SFNT_DIR)/ttload.c \
$(SFNT_DIR)/ttmtx.c \
$(SFNT_DIR)/ttcmap.c \
$(SFNT_DIR)/ttsbit.c \
$(SFNT_DIR)/ttcolr.c \
$(SFNT_DIR)/ttpost.c \
$(SFNT_DIR)/ttkern.c \
$(SFNT_DIR)/ttbdf.c \

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@ -32,6 +32,10 @@
#include "ttsbit.h"
#endif
#ifdef TT_CONFIG_OPTION_COLOR_LAYERS
#include "ttcolr.h"
#endif
#ifdef TT_CONFIG_OPTION_POSTSCRIPT_NAMES
#include "ttpost.h"
#endif
@ -1185,6 +1189,12 @@
#define PUT_EMBEDDED_BITMAPS( a ) NULL
#endif
#ifdef TT_CONFIG_OPTION_COLOR_LAYERS
#define PUT_COLOR_LAYERS( a ) a
#else
#define PUT_COLOR_LAYERS( a ) NULL
#endif
#ifdef TT_CONFIG_OPTION_POSTSCRIPT_NAMES
#define PUT_PS_NAMES( a ) a
#else
@ -1243,9 +1253,18 @@
/* TT_Free_Table_Func free_eblc */
PUT_EMBEDDED_BITMAPS( tt_face_set_sbit_strike ),
/* TT_Set_SBit_Strike_Func set_sbit_strike */
/* TT_Set_SBit_Strike_Func set_sbit_strike */
PUT_EMBEDDED_BITMAPS( tt_face_load_strike_metrics ),
/* TT_Load_Strike_Metrics_Func load_strike_metrics */
/* TT_Load_Strike_Metrics_Func load_strike_metrics */
PUT_COLOR_LAYERS( tt_face_load_colr ),
/* TT_Load_Table_Func load_colr */
PUT_COLOR_LAYERS( tt_face_free_colr ),
/* TT_Free_Table_Func free_colr */
PUT_COLOR_LAYERS( tt_face_load_colr_layers ),
/* TT_Load_Colr_Layer_Func load_colr_layer */
PUT_COLOR_LAYERS( tt_face_colr_blend_layer ),
/* TT_Blend_Colr_Func colr_blend */
tt_face_get_metrics, /* TT_Get_Metrics_Func get_metrics */

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@ -24,6 +24,8 @@
#include "sfobjs.c"
#include "ttbdf.c"
#include "ttcmap.c"
#include "ttcolr.c"
#include "ttkern.c"
#include "ttload.c"
#include "ttmtx.c"

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@ -1341,6 +1341,12 @@
if ( sfnt->load_eblc )
LOAD_( eblc );
if ( sfnt->load_colr )
{
/* Ignore error. Missing optional colr/cpal is okay. */
LOAD_( colr );
}
/* consider the pclt, kerning, and gasp tables as optional */
LOAD_( pclt );
LOAD_( gasp );
@ -1394,7 +1400,8 @@
/* Compute face flags. */
/* */
if ( face->sbit_table_type == TT_SBIT_TABLE_TYPE_CBLC ||
face->sbit_table_type == TT_SBIT_TABLE_TYPE_SBIX )
face->sbit_table_type == TT_SBIT_TABLE_TYPE_SBIX ||
face->colr_and_cpal )
flags |= FT_FACE_FLAG_COLOR; /* color glyphs */
if ( has_outline == TRUE )
@ -1737,6 +1744,10 @@
/* destroy the embedded bitmaps table if it is loaded */
if ( sfnt->free_eblc )
sfnt->free_eblc( face );
/* destroy color table data if it is loaded */
if ( sfnt->free_colr )
sfnt->free_colr( face );
}
#ifdef TT_CONFIG_OPTION_BDF

546
src/sfnt/ttcolr.c Normal file
View File

@ -0,0 +1,546 @@
/***************************************************************************/
/* */
/* ttcolr.c */
/* */
/* TrueType and OpenType color outline support. */
/* */
/* Copyright 2018 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* Written by Shao Yu Zhang <shaozhang@fb.com>. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
/*************************************************************************/
/* */
/* `COLR' and `CPAL' table specification: */
/* */
/* https://www.microsoft.com/typography/otspec/colr.htm */
/* https://www.microsoft.com/typography/otspec/cpal.htm */
/* */
/*************************************************************************/
#include <ft2build.h>
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H
#include FT_TRUETYPE_TAGS_H
#ifdef TT_CONFIG_OPTION_COLOR_LAYERS
#include "ttcolr.h"
/* NOTE: These are the table sizes calculated through the specs. */
#define BASE_GLYPH_SIZE 6
#define LAYER_SIZE 4
#define COLR_HEADER_SIZE 14
#define CPAL_V0_HEADER_BASE_SIZE 12
#define COLOR_SIZE 4
typedef struct BaseGlyphRecord_
{
FT_UShort gid;
FT_UShort first_layer_index;
FT_UShort num_layers;
} BaseGlyphRecord;
typedef struct Colr_
{
FT_UShort version;
FT_UShort num_base_glyphs;
FT_UShort num_layers;
FT_Byte* base_glyphs;
FT_Byte* layers;
} Colr;
typedef struct Cpal_
{
FT_UShort version; /* Table version number (0 or 1 supported). */
FT_UShort num_palettes_entries; /* # of entries in each palette. */
FT_UShort num_palettes; /* # of palettes in the table. */
FT_UShort num_colors; /* Total number of color records, */
/* combined for all palettes. */
FT_Byte* colors; /* RGBA array of colors */
FT_Byte* color_indices; /* Index of each palette's first color record */
/* in the combined color record array. */
/* version 1 fields */
FT_ULong* palette_types;
FT_UShort* palette_labels;
FT_UShort* palette_entry_labels;
} Cpal;
typedef struct ColrCpal_
{
/* Accessors into the colr/cpal tables. */
Colr colr;
Cpal cpal;
/* The memory which backs up colr/cpal tables. */
void* colr_table;
void* cpal_table;
} ColrCpal;
/*************************************************************************/
/* */
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
/* messages during execution. */
/* */
#undef FT_COMPONENT
#define FT_COMPONENT trace_ttcolrcpal
FT_LOCAL_DEF( FT_Error )
tt_face_load_colr( TT_Face face,
FT_Stream stream )
{
FT_Error error;
FT_Memory memory = face->root.memory;
FT_Byte* colr_table = NULL;
FT_Byte* cpal_table = NULL;
FT_Byte* p = NULL;
Colr colr;
Cpal cpal;
ColrCpal* cc = NULL;
FT_ULong base_glyph_begin, base_glyph_end, layer_begin, layer_end;
FT_ULong colors_begin, colors_end;
FT_ULong table_size;
face->colr_and_cpal = NULL;
error = face->goto_table( face, TTAG_COLR, stream, &table_size );
if ( error )
goto NoColor;
if ( table_size < sizeof ( COLR_HEADER_SIZE ) )
goto InvalidTable;
if ( FT_FRAME_EXTRACT( table_size, colr_table ) )
goto NoColor;
p = colr_table;
FT_ZERO( &colr );
colr.version = FT_NEXT_USHORT( p );
colr.num_base_glyphs = FT_NEXT_USHORT( p );
base_glyph_begin = FT_NEXT_ULONG( p );
layer_begin = FT_NEXT_ULONG( p );
colr.num_layers = FT_NEXT_USHORT( p );
colr.base_glyphs = (FT_Byte*)( colr_table + base_glyph_begin );
colr.layers = (FT_Byte*)( colr_table + layer_begin );
if ( colr.version != 0 )
goto InvalidTable;
/* Ensure variable length tables lies within the COLR table. */
/* We wrap around FT_ULong at most once since count is FT_UShort. */
base_glyph_end = base_glyph_begin +
colr.num_base_glyphs * BASE_GLYPH_SIZE;
layer_end = layer_begin +
colr.num_layers * LAYER_SIZE;
if ( base_glyph_end < base_glyph_begin || base_glyph_end > table_size ||
layer_end < layer_begin || layer_end > table_size )
goto InvalidTable;
/* Ensure pointers don't wrap. */
if ( colr.base_glyphs < colr_table || colr.layers < colr_table )
goto InvalidTable;
error = face->goto_table( face, TTAG_CPAL, stream, &table_size );
if ( error )
goto NoColor;
if ( table_size < CPAL_V0_HEADER_BASE_SIZE )
goto InvalidTable;
if ( FT_FRAME_EXTRACT( table_size, cpal_table ) )
goto NoColor;
p = cpal_table;
FT_ZERO( &cpal );
cpal.version = FT_NEXT_USHORT( p );
cpal.num_palettes_entries = FT_NEXT_USHORT( p );
cpal.num_palettes = FT_NEXT_USHORT( p );
cpal.num_colors = FT_NEXT_USHORT( p );
colors_begin = FT_NEXT_ULONG( p );
cpal.color_indices = p;
cpal.colors = (FT_Byte*)cpal_table + colors_begin;
if ( cpal.version != 0 && cpal.version != 1 )
goto InvalidTable;
colors_end = colors_begin + cpal.num_colors * COLOR_SIZE;
/* Ensure variable length tables lies within the COLR table. */
/* We wrap around FT_ULong at most once since count is FT_UShort. */
if ( colors_end < colors_begin || colors_end > table_size )
goto InvalidTable;
if ( cpal.colors < cpal_table )
goto InvalidTable;
if ( FT_NEW( cc ) )
goto NoColor;
cc->colr = colr;
cc->cpal = cpal;
cc->colr_table = colr_table;
cc->cpal_table = cpal_table;
face->colr_and_cpal = cc;
return FT_Err_Ok;
InvalidTable:
error = FT_THROW( Invalid_File_Format );
NoColor:
if ( colr_table )
FT_FRAME_RELEASE( colr_table );
if ( cpal_table )
FT_FRAME_RELEASE( cpal_table );
return error;
}
FT_LOCAL_DEF( void )
tt_face_free_colr( TT_Face face )
{
FT_Stream stream = face->root.stream;
FT_Memory memory = face->root.memory;
ColrCpal* colr_and_cpal = (ColrCpal*)face->colr_and_cpal;
if ( colr_and_cpal )
{
FT_FRAME_RELEASE( colr_and_cpal->colr_table );
FT_FRAME_RELEASE( colr_and_cpal->cpal_table );
FT_FREE( face->colr_and_cpal );
}
}
static FT_Bool
find_base_glyph_record( FT_Byte* base_glyph_begin,
FT_Int num_base_glyph,
FT_UShort glyph_id,
BaseGlyphRecord* record )
{
FT_Int min = 0;
FT_Int max = num_base_glyph - 1;
while ( min <= max )
{
FT_Int mid = min + ( max - min ) / 2;
FT_Byte* p = base_glyph_begin + mid * BASE_GLYPH_SIZE;
FT_UShort gid = FT_NEXT_USHORT( p );
if ( gid < glyph_id )
min = mid + 1;
else if (gid > glyph_id )
max = mid - 1;
else
{
record->gid = gid;
record->first_layer_index = FT_NEXT_USHORT( p );
record->num_layers = FT_NEXT_USHORT( p );
return 1;
}
}
return 0;
}
FT_LOCAL_DEF( FT_Error )
tt_face_load_colr_layers( TT_Face face,
FT_Int glyph_id,
FT_Glyph_LayerRec* *ret_layers,
FT_UShort* ret_num_layers )
{
FT_Error error;
FT_Memory memory = face->root.memory;
ColrCpal* colr_and_cpal = (ColrCpal *)face->colr_and_cpal;
Colr* colr = &colr_and_cpal->colr;
Cpal* cpal = &colr_and_cpal->cpal;
BaseGlyphRecord glyph_record;
FT_Glyph_LayerRec* layers;
int layer_idx;
FT_Byte* layer_record_ptr;
if ( !ret_layers || !ret_num_layers )
return FT_THROW( Invalid_Argument );
if ( !find_base_glyph_record( colr->base_glyphs,
colr->num_base_glyphs,
glyph_id,
&glyph_record ) )
return FT_THROW ( Invalid_Table );
/* Load all colors for the glyphs; this would be stored in the slot. */
layer_record_ptr = colr->layers +
glyph_record.first_layer_index * LAYER_SIZE;
if ( FT_NEW_ARRAY( layers, glyph_record.num_layers ) )
goto Error;
for ( layer_idx = 0; layer_idx < glyph_record.num_layers; layer_idx++ )
{
FT_UShort gid = FT_NEXT_USHORT( layer_record_ptr );
FT_UShort palette_index = FT_NEXT_USHORT( layer_record_ptr );
if ( palette_index != 0xFFFF &&
palette_index >= cpal->num_palettes_entries )
{
error = FT_THROW( Invalid_File_Format );
goto Error;
}
layers[layer_idx].color_index = palette_index;
layers[layer_idx].glyph_index = gid;
}
*ret_layers = layers;
*ret_num_layers = glyph_record.num_layers;
return FT_Err_Ok;
Error:
if ( layers )
FT_FREE( layers );
return error;
}
static FT_Bool
tt_face_find_color( TT_Face face,
FT_UShort color_index,
FT_Byte* blue,
FT_Byte* green,
FT_Byte* red,
FT_Byte* alpha )
{
ColrCpal* colr_and_cpal = (ColrCpal *)face->colr_and_cpal;
Cpal* cpal = &colr_and_cpal->cpal;
FT_Int palette_index = 0;
FT_Byte* p;
FT_Int color_offset;
if ( color_index >= cpal->num_palettes_entries )
return 0;
p = cpal->color_indices + palette_index * sizeof ( FT_UShort );
color_offset = FT_NEXT_USHORT( p );
p = cpal->colors + color_offset + COLOR_SIZE * color_index;
*red = FT_NEXT_BYTE( p );
*green = FT_NEXT_BYTE( p );
*blue = FT_NEXT_BYTE( p );
*alpha = FT_NEXT_BYTE( p );
return 1;
}
FT_LOCAL_DEF( FT_Error )
tt_face_colr_blend_layer( TT_Face face,
FT_Int color_index,
FT_GlyphSlot dstSlot,
FT_GlyphSlot srcSlot )
{
FT_Error error;
FT_UInt x, y;
FT_Byte b, g, r, alpha;
FT_Long size;
FT_Byte* src;
FT_Byte* dst;
if ( !dstSlot->bitmap.buffer )
{
/* Initialize destination of color bitmap */
/* with the size of first component. */
dstSlot->bitmap_left = srcSlot->bitmap_left;
dstSlot->bitmap_top = srcSlot->bitmap_top;
dstSlot->bitmap.width = srcSlot->bitmap.width;
dstSlot->bitmap.rows = srcSlot->bitmap.rows;
dstSlot->bitmap.pixel_mode = FT_PIXEL_MODE_BGRA;
dstSlot->bitmap.pitch = dstSlot->bitmap.width * 4;
dstSlot->bitmap.num_grays = 256;
size = dstSlot->bitmap.rows * dstSlot->bitmap.pitch;
error = ft_glyphslot_alloc_bitmap( dstSlot, size );
if ( error )
return error;
FT_MEM_ZERO( dstSlot->bitmap.buffer, size );
}
else
{
/* Resize destination if needed such that new component fits. */
FT_Int x_min, x_max, y_min, y_max;
x_min = FT_MIN( dstSlot->bitmap_left, srcSlot->bitmap_left );
x_max = FT_MAX( dstSlot->bitmap_left + (FT_Int)dstSlot->bitmap.width,
srcSlot->bitmap_left + (FT_Int)srcSlot->bitmap.width );
y_min = FT_MIN( dstSlot->bitmap_top - (FT_Int)dstSlot->bitmap.rows,
srcSlot->bitmap_top - (FT_Int)srcSlot->bitmap.rows );
y_max = FT_MAX( dstSlot->bitmap_top, srcSlot->bitmap_top );
if ( x_min != dstSlot->bitmap_left ||
x_max != dstSlot->bitmap_left + (FT_Int)dstSlot->bitmap.width ||
y_min != dstSlot->bitmap_top - (FT_Int)dstSlot->bitmap.rows ||
y_max != dstSlot->bitmap_top )
{
FT_Memory memory = face->root.memory;
FT_UInt width = x_max - x_min;
FT_UInt rows = y_max - y_min;
FT_UInt pitch = width * 4;
FT_Byte* buf;
FT_Byte* p;
FT_Byte* q;
size = rows * pitch;
if ( FT_ALLOC( buf, size ) )
return error;
p = dstSlot->bitmap.buffer;
q = buf +
pitch * ( y_max - dstSlot->bitmap_top ) +
4 * ( dstSlot->bitmap_left - x_min );
for ( y = 0; y < dstSlot->bitmap.rows; y++ )
{
FT_MEM_COPY( q, p, dstSlot->bitmap.width * 4 );
p += dstSlot->bitmap.pitch;
q += pitch;
}
ft_glyphslot_set_bitmap( dstSlot, buf );
dstSlot->bitmap_top = y_max;
dstSlot->bitmap_left = x_min;
dstSlot->bitmap.width = width;
dstSlot->bitmap.rows = rows;
dstSlot->bitmap.pitch = pitch;
dstSlot->internal->flags |= FT_GLYPH_OWN_BITMAP;
dstSlot->format = FT_GLYPH_FORMAT_BITMAP;
}
}
/* Default assignments to pacify compiler. */
r = g = b = 0;
alpha = 255;
if ( color_index != 0xFFFF )
tt_face_find_color( face, color_index, &b, &g, &r, &alpha );
else
{
/* TODO. foreground color from argument? */
/* Add public FT_Render_Glyph_Color() with color value? */
}
/* XXX Convert if srcSlot.bitmap is not grey? */
src = srcSlot->bitmap.buffer;
dst = dstSlot->bitmap.buffer +
dstSlot->bitmap.pitch * ( dstSlot->bitmap_top - srcSlot->bitmap_top ) +
4 * ( srcSlot->bitmap_left - dstSlot->bitmap_left );
for ( y = 0; y < srcSlot->bitmap.rows; y++ )
{
for ( x = 0; x < srcSlot->bitmap.width; x++ )
{
int aa = src[x];
int fa = alpha * aa / 255;
int fb = b * fa / 255;
int fg = g * fa / 255;
int fr = r * fa / 255;
int ba2 = 255 - fa;
int bb = dst[4 * x + 0];
int bg = dst[4 * x + 1];
int br = dst[4 * x + 2];
int ba = dst[4 * x + 3];
dst[4 * x + 0] = bb * ba2 / 255 + fb;
dst[4 * x + 1] = bg * ba2 / 255 + fg;
dst[4 * x + 2] = br * ba2 / 255 + fr;
dst[4 * x + 3] = ba * ba2 / 255 + fa;
}
src += srcSlot->bitmap.pitch;
dst += dstSlot->bitmap.pitch;
}
return FT_Err_Ok;
}
#else /* !TT_CONFIG_OPTION_COLOR_LAYERS */
/* ANSI C doesn't like empty source files */
typedef int _tt_colr_dummy;
#endif /* !TT_CONFIG_OPTION_COLOR_LAYERS */
/* EOF */

57
src/sfnt/ttcolr.h Normal file
View File

@ -0,0 +1,57 @@
/***************************************************************************/
/* */
/* ttsbit.h */
/* */
/* TrueType and OpenType color outline support (specification). */
/* */
/* Copyright 2018 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* Written by Shao Yu Zhang <shaozhang@fb.com>. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#ifndef __TTCOLR_H__
#define __TTCOLR_H__
#include <ft2build.h>
#include "ttload.h"
FT_BEGIN_HEADER
FT_LOCAL( FT_Error )
tt_face_load_colr( TT_Face face,
FT_Stream stream );
FT_LOCAL( void )
tt_face_free_colr( TT_Face face );
FT_LOCAL( FT_Error )
tt_face_load_colr_layers( TT_Face face,
FT_Int glyph_id,
FT_Glyph_LayerRec* *ret_layers,
FT_UShort* ret_num_layers );
FT_LOCAL( FT_Error )
tt_face_colr_blend_layer( TT_Face face,
FT_Int color_index,
FT_GlyphSlot dstSlot,
FT_GlyphSlot srcSlot );
FT_END_HEADER
#endif /* __TTCOLR_H__ */
/* END */

View File

@ -463,7 +463,7 @@
? &ttsize->metrics
: &size->hinted_metrics;
/* now load the glyph outline if necessary */
/* now fill in the glyph slot with outline/bitmap/layered */
error = TT_Load_Glyph( size, slot, glyph_index, load_flags );
/* force drop-out mode to 2 - irrelevant now */

View File

@ -2892,6 +2892,37 @@
size->metrics->y_ppem < 24 )
glyph->outline.flags |= FT_OUTLINE_HIGH_PRECISION;
/* The outline based algorithm took care of metrics. */
/* Read additional color info if requested. */
if ( ( load_flags & FT_LOAD_COLOR ) &&
( (TT_Face)(glyph->face) )->colr_and_cpal )
{
TT_Face face = (TT_Face)glyph->face;
FT_Memory memory = face->root.memory;
SFNT_Service sfnt = (SFNT_Service)face->sfnt;
FT_Glyph_LayerRec* glyph_layers;
FT_UShort num_glyph_layers;
FT_Colr_Internal color_layers;
error = sfnt->load_colr_layer( face,
glyph_index,
&glyph_layers,
&num_glyph_layers );
if ( error )
return error;
if ( FT_NEW( color_layers ) )
return error;
color_layers->layers = glyph_layers;
color_layers->num_layers = num_glyph_layers;
color_layers->load_flags = load_flags;
glyph->internal->color_layers = color_layers;
}
Exit:
#ifdef FT_DEBUG_LEVEL_TRACE
if ( error )