ref: f93a897afedf4a634c74d3d2871519e675ee0d83
parent: 06c1a25e63b70a1a9e0f6edc18af1e9361a1c52a
author: Moazin Khatti <[email protected]>
date: Sat Dec 25 14:20:44 EST 2021
Add code to load OT-SVG glyph documents. * include/freetype/config/ftheader.h (FT_OTSVG_H): New macro. * include/freetype/freetype.h (FT_FACE_FLAG_SVG, FT_HAS_SVG): New macros. (FT_LOAD_SVG_ONLY): New internal macro. * include/freetype/ftimage.h (FT_Glyph_Format): New enumeration value `FT_GLYPH_FORMAT_SVG`. * include/freetype/internal/ftobjs.h (FT_GLYPH_OWN_GZIP_SVG): New macro. * include/freetype/internal/fttrace.h: Add `ttsvg` for `ttsvg.c`. * include/freetype/internal/sfnt.h(load_svg, free_svg, load_svg_doc): New functions. * include/freetype/internal/tttypes.h (TT_FaceRec): Add `svg` for the SVG table. * include/freetype/otsvg.h (FT_SVG_DocumentRec): New structure to hold the SVG document and other necessary information of an OT-SVG glyph in a glyph slot. * include/freetype/tttags.h (TTAG_SVG): New macro. * src/base/ftobjs.c: Include `otsvg.h`. (ft_glyphslot_init): Allocate `FT_SVG_DocumentRec` in `slot->other` if the SVG table exists. (ft_glyphslot_clear): Free it upon clean-up if it is a GZIP compressed glyph. (ft_glyphslot_done): Free the document data if it is a GZIP compressed glyph. (FT_Load_Glyph): Don't auto-hint SVG documents. * src/cache/ftcbasic.c (ftc_basic_family_load_glyph): Add support for FT_GLYPH_FORMAT_SVG. * src/sfnt/rules.mk (SFNT_DRV_SRC): Add `ttsvg.c`. * src/sfnt/sfdriver.c: Include `ttsvg.h`. (sfnt_interface): Add `tt_face_load_svg`, `tt_face_free_svg` and `tt_face_load_svg_doc`. * src/sfnt/sfnt.c: Include `ttsvg.c`. * src/sfnt/sfobjs.c (sfnt_load_face, sfnt_done_face): Add code to load and free data of the the SVG table. * src/sfnt/ttsvg.c: New file, implementing `tt_face_load_svg`, `tt_face_free_svg` and `tt_face_load_svg_doc`. * src/sfnt/ttsvg.h: Declarations of the SVG functions in `ttsvg.c`.
--- a/include/freetype/config/ftheader.h
+++ b/include/freetype/config/ftheader.h
@@ -777,6 +777,18 @@
#define FT_COLOR_H <freetype/ftcolor.h>
+ /**************************************************************************
+ *
+ * @macro:
+ * FT_OTSVG_H
+ *
+ * @description:
+ * A macro used in `#include` statements to name the file containing the
+ * FreeType~2 API which handles the OpenType 'SVG~' glyphs.
+ */
+#define FT_OTSVG_H <freetype/otsvg.h>
+
+
/* */
/* These header files don't need to be included by the user. */
--- a/include/freetype/freetype.h
+++ b/include/freetype/freetype.h
@@ -153,6 +153,7 @@
* FT_FACE_FLAG_GLYPH_NAMES
* FT_FACE_FLAG_EXTERNAL_STREAM
* FT_FACE_FLAG_HINTER
+ * FT_FACE_FLAG_SVG
*
* FT_HAS_HORIZONTAL
* FT_HAS_VERTICAL
@@ -161,6 +162,7 @@
* FT_HAS_GLYPH_NAMES
* FT_HAS_COLOR
* FT_HAS_MULTIPLE_MASTERS
+ * FT_HAS_SVG
*
* FT_IS_SFNT
* FT_IS_SCALABLE
@@ -1230,6 +1232,9 @@
* altered with @FT_Set_MM_Design_Coordinates,
* @FT_Set_Var_Design_Coordinates, or @FT_Set_Var_Blend_Coordinates.
* This flag is unset by a call to @FT_Set_Named_Instance.
+ *
+ * FT_FACE_FLAG_SVG ::
+ * [Since 2.12] The face has an 'SVG~' OpenType table.
*/
#define FT_FACE_FLAG_SCALABLE ( 1L << 0 )
#define FT_FACE_FLAG_FIXED_SIZES ( 1L << 1 )
@@ -1247,6 +1252,7 @@
#define FT_FACE_FLAG_TRICKY ( 1L << 13 )
#define FT_FACE_FLAG_COLOR ( 1L << 14 )
#define FT_FACE_FLAG_VARIATION ( 1L << 15 )
+#define FT_FACE_FLAG_SVG ( 1L << 16 )
/**************************************************************************
@@ -1489,6 +1495,22 @@
/**************************************************************************
*
+ * @macro:
+ * FT_HAS_SVG
+ *
+ * @description:
+ * A macro that returns true whenever a face object contains an 'SVG~'
+ * OpenType table.
+ *
+ * @since:
+ * 2.12
+ */
+#define FT_HAS_SVG( face ) \
+ ( !!( (face)->face_flags & FT_FACE_FLAG_SVG ) )
+
+
+ /**************************************************************************
+ *
* @enum:
* FT_STYLE_FLAG_XXX
*
@@ -3075,15 +3097,15 @@
*
*/
#define FT_LOAD_DEFAULT 0x0
-#define FT_LOAD_NO_SCALE ( 1L << 0 )
-#define FT_LOAD_NO_HINTING ( 1L << 1 )
-#define FT_LOAD_RENDER ( 1L << 2 )
-#define FT_LOAD_NO_BITMAP ( 1L << 3 )
-#define FT_LOAD_VERTICAL_LAYOUT ( 1L << 4 )
-#define FT_LOAD_FORCE_AUTOHINT ( 1L << 5 )
-#define FT_LOAD_CROP_BITMAP ( 1L << 6 )
-#define FT_LOAD_PEDANTIC ( 1L << 7 )
-#define FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ( 1L << 9 )
+#define FT_LOAD_NO_SCALE ( 1L << 0 )
+#define FT_LOAD_NO_HINTING ( 1L << 1 )
+#define FT_LOAD_RENDER ( 1L << 2 )
+#define FT_LOAD_NO_BITMAP ( 1L << 3 )
+#define FT_LOAD_VERTICAL_LAYOUT ( 1L << 4 )
+#define FT_LOAD_FORCE_AUTOHINT ( 1L << 5 )
+#define FT_LOAD_CROP_BITMAP ( 1L << 6 )
+#define FT_LOAD_PEDANTIC ( 1L << 7 )
+#define FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ( 1L << 9 )
#define FT_LOAD_NO_RECURSE ( 1L << 10 )
#define FT_LOAD_IGNORE_TRANSFORM ( 1L << 11 )
#define FT_LOAD_MONOCHROME ( 1L << 12 )
@@ -3097,8 +3119,9 @@
/* */
/* used internally only by certain font drivers */
-#define FT_LOAD_ADVANCE_ONLY ( 1L << 8 )
+#define FT_LOAD_ADVANCE_ONLY ( 1L << 8 )
#define FT_LOAD_SBITS_ONLY ( 1L << 14 )
+#define FT_LOAD_SVG_ONLY ( 1L << 23 )
/**************************************************************************
--- a/include/freetype/ftglyph.h
+++ b/include/freetype/ftglyph.h
@@ -181,7 +181,7 @@
*
* @description:
* A handle to an object used to model an outline glyph image. This is a
- * sub-class of @FT_Glyph, and a pointer to @FT_OutlineGlyphRec.
+ * 'sub-class' of @FT_Glyph, and a pointer to @FT_OutlineGlyphRec.
*/
typedef struct FT_OutlineGlyphRec_* FT_OutlineGlyph;
--- a/include/freetype/ftimage.h
+++ b/include/freetype/ftimage.h
@@ -741,6 +741,10 @@
* contours. Some Type~1 fonts, like those in the Hershey family,
* contain glyphs in this format. These are described as @FT_Outline,
* but FreeType isn't currently capable of rendering them correctly.
+ *
+ * FT_GLYPH_FORMAT_SVG ::
+ * [Since 2.12] The glyph is represented by an SVG document in the
+ * 'SVG~' table.
*/
typedef enum FT_Glyph_Format_
{
@@ -749,7 +753,8 @@
FT_IMAGE_TAG( FT_GLYPH_FORMAT_COMPOSITE, 'c', 'o', 'm', 'p' ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_BITMAP, 'b', 'i', 't', 's' ),
FT_IMAGE_TAG( FT_GLYPH_FORMAT_OUTLINE, 'o', 'u', 't', 'l' ),
- FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER, 'p', 'l', 'o', 't' )
+ FT_IMAGE_TAG( FT_GLYPH_FORMAT_PLOTTER, 'p', 'l', 'o', 't' ),
+ FT_IMAGE_TAG( FT_GLYPH_FORMAT_SVG, 'S', 'V', 'G', ' ' )
} FT_Glyph_Format;
--- a/include/freetype/internal/ftobjs.h
+++ b/include/freetype/internal/ftobjs.h
@@ -418,7 +418,8 @@
* initializing the glyph slot.
*/
-#define FT_GLYPH_OWN_BITMAP 0x1U
+#define FT_GLYPH_OWN_BITMAP 0x1U
+#define FT_GLYPH_OWN_GZIP_SVG 0x2U
typedef struct FT_Slot_InternalRec_
{
--- a/include/freetype/internal/fttrace.h
+++ b/include/freetype/internal/fttrace.h
@@ -61,6 +61,7 @@
FT_TRACE_DEF( ttcmap ) /* charmap handler (ttcmap.c) */
FT_TRACE_DEF( ttcolr ) /* glyph layer table (ttcolr.c) */
FT_TRACE_DEF( ttcpal ) /* color palette table (ttcpal.c) */
+FT_TRACE_DEF( ttsvg ) /* OpenType SVG table (ttsvg.c) */
FT_TRACE_DEF( ttkern ) /* kerning handler (ttkern.c) */
FT_TRACE_DEF( ttload ) /* basic TrueType tables (ttload.c) */
FT_TRACE_DEF( ttmtx ) /* metrics-related tables (ttmtx.c) */
--- a/include/freetype/internal/sfnt.h
+++ b/include/freetype/internal/sfnt.h
@@ -314,6 +314,33 @@
/**************************************************************************
*
* @functype:
+ * TT_Load_Svg_Doc_Func
+ *
+ * @description:
+ * Scan the SVG document list to find the document containing the glyph
+ * that has the ID 'glyph*XXX*', where *XXX* is the value of
+ * `glyph_index` as a decimal integer.
+ *
+ * @inout:
+ * glyph ::
+ * The glyph slot from which pointers to the SVG document list is to be
+ * grabbed. The results are stored back in the slot.
+ *
+ * @input:
+ * glyph_index ::
+ * The index of the glyph that is to be looked up.
+ *
+ * @return:
+ * FreeType error code. 0 means success.
+ */
+ typedef FT_Error
+ (*TT_Load_Svg_Doc_Func)( FT_GlyphSlot glyph,
+ FT_UInt glyph_index );
+
+
+ /**************************************************************************
+ *
+ * @functype:
* TT_Set_SBit_Strike_Func
*
* @description:
@@ -946,6 +973,11 @@
TT_Get_Name_Func get_name;
TT_Get_Name_ID_Func get_name_id;
+ /* OpenType SVG Support */
+ TT_Load_Table_Func load_svg;
+ TT_Free_Table_Func free_svg;
+ TT_Load_Svg_Doc_Func load_svg_doc;
+
} SFNT_Interface;
@@ -997,7 +1029,10 @@
colr_blend_, \
get_metrics_, \
get_name_, \
- get_name_id_ ) \
+ get_name_id_, \
+ load_svg_, \
+ free_svg_, \
+ load_svg_doc_ ) \
static const SFNT_Interface class_ = \
{ \
goto_table_, \
@@ -1042,7 +1077,10 @@
colr_blend_, \
get_metrics_, \
get_name_, \
- get_name_id_ \
+ get_name_id_, \
+ load_svg_, \
+ free_svg_, \
+ load_svg_doc_ \
};
--- a/include/freetype/internal/tttypes.h
+++ b/include/freetype/internal/tttypes.h
@@ -1644,6 +1644,9 @@
void* cpal;
void* colr;
+ /* since 2.12 */
+ void* svg;
+
} TT_FaceRec;
--- /dev/null
+++ b/include/freetype/otsvg.h
@@ -1,0 +1,114 @@
+/****************************************************************************
+ *
+ * otsvg.h
+ *
+ * Interface for OT-SVG support related things (specification).
+ *
+ * Copyright (C) 2022 by
+ * David Turner, Robert Wilhelm, Werner Lemberg, and Moazin Khatti.
+ *
+ * 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 OTSVG_H_
+#define OTSVG_H_
+
+#include <freetype/freetype.h>
+
+#ifdef FREETYPE_H
+#error "freetype.h of FreeType 1 has been loaded!"
+#error "Please fix the directory search order for header files"
+#error "so that freetype.h of FreeType 2 is found first."
+#endif
+
+
+FT_BEGIN_HEADER
+
+ /**************************************************************************
+ *
+ * @struct:
+ * FT_SVG_DocumentRec_
+ *
+ * @description:
+ * A structure that models one SVG document.
+ *
+ * @fields:
+ * svg_document ::
+ * A pointer to the SVG document.
+ *
+ * svg_document_length ::
+ * The length of `svg_document`.
+ *
+ * metrics ::
+ * A metrics object storing the size information.
+ *
+ * units_per_EM ::
+ * The size of the EM square.
+ *
+ * start_glyph_id ::
+ * The first glyph ID in the glyph range covered by this document.
+ *
+ * end_glyph_id ::
+ * The last glyph ID in the glyph range covered by this document.
+ *
+ * transform ::
+ * A 2x2 transformation matrix to apply to the glyph while rendering
+ * it.
+ *
+ * delta ::
+ * The translation to apply to the glyph while rendering.
+ *
+ * @note:
+ * When the slot is passed down to a renderer, the renderer can only
+ * access the `metrics` and `units_per_EM` fields via `slot->face`.
+ * However, when `FT_Glyph_To_Bitmap` sets up a dummy object, it has no
+ * way to set a `face` object. Thus, metrics information and
+ * `units_per_EM` (which is necessary for OT-SVG) has to be stored
+ * separately.
+ *
+ * @since:
+ * 2.12
+ */
+ typedef struct FT_SVG_DocumentRec_
+ {
+ FT_Byte* svg_document;
+ FT_ULong svg_document_length;
+
+ FT_Size_Metrics metrics;
+ FT_UShort units_per_EM;
+
+ FT_UShort start_glyph_id;
+ FT_UShort end_glyph_id;
+
+ FT_Matrix transform;
+ FT_Vector delta;
+
+ } FT_SVG_DocumentRec;
+
+
+ /**************************************************************************
+ *
+ * @type:
+ * FT_SVG_Document
+ *
+ * @description:
+ * A handle to an @FT_SVG_DocumentRec object.
+ *
+ * @since:
+ * 2.12
+ */
+ typedef struct FT_SVG_DocumentRec_* FT_SVG_Document;
+
+
+FT_END_HEADER
+
+#endif /* OTSVG_H_ */
+
+
+/* END */
--- a/include/freetype/tttags.h
+++ b/include/freetype/tttags.h
@@ -95,6 +95,7 @@
#define TTAG_sbix FT_MAKE_TAG( 's', 'b', 'i', 'x' )
#define TTAG_sfnt FT_MAKE_TAG( 's', 'f', 'n', 't' )
#define TTAG_SING FT_MAKE_TAG( 'S', 'I', 'N', 'G' )
+#define TTAG_SVG FT_MAKE_TAG( 'S', 'V', 'G', ' ' )
#define TTAG_trak FT_MAKE_TAG( 't', 'r', 'a', 'k' )
#define TTAG_true FT_MAKE_TAG( 't', 'r', 'u', 'e' )
#define TTAG_ttc FT_MAKE_TAG( 't', 't', 'c', ' ' )
--- a/src/base/ftobjs.c
+++ b/src/base/ftobjs.c
@@ -19,6 +19,7 @@
#include <freetype/ftlist.h>
#include <freetype/ftoutln.h>
#include <freetype/ftfntfmt.h>
+#include <freetype/otsvg.h>
#include <freetype/internal/ftvalid.h>
#include <freetype/internal/ftobjs.h>
@@ -328,6 +329,19 @@
if ( !error && clazz->init_slot )
error = clazz->init_slot( slot );
+#ifdef FT_CONFIG_OPTION_SVG
+ /* if SVG table exists, allocate the space in `slot->other` */
+ if ( slot->face->face_flags & FT_FACE_FLAG_SVG )
+ {
+ FT_SVG_Document document;
+
+
+ if ( FT_NEW( document ) )
+ goto Exit;
+ slot->other = document;
+ }
+#endif
+
Exit:
return error;
}
@@ -564,9 +578,28 @@
slot->subglyphs = NULL;
slot->control_data = NULL;
slot->control_len = 0;
- slot->other = NULL;
- slot->format = FT_GLYPH_FORMAT_NONE;
+#ifndef FT_CONFIG_OPTION_SVG
+ slot->other = NULL;
+#else
+ if ( !( slot->face->face_flags & FT_FACE_FLAG_SVG ) )
+ slot->other = NULL;
+ else
+ {
+ if ( slot->internal->flags & FT_GLYPH_OWN_GZIP_SVG )
+ {
+ FT_Memory memory = slot->face->memory;
+ FT_SVG_Document doc = (FT_SVG_Document)slot->other;
+
+
+ FT_FREE( doc->svg_document );
+ slot->internal->load_flags &= ~FT_GLYPH_OWN_GZIP_SVG;
+ }
+ }
+#endif
+
+ slot->format = FT_GLYPH_FORMAT_NONE;
+
slot->linearHoriAdvance = 0;
slot->linearVertAdvance = 0;
slot->advance.x = 0;
@@ -583,7 +616,24 @@
FT_Driver_Class clazz = driver->clazz;
FT_Memory memory = driver->root.memory;
+#ifdef FT_CONFIG_OPTION_SVG
+ if ( slot->face->face_flags & FT_FACE_FLAG_SVG )
+ {
+ /* free memory in case SVG was there */
+ if ( slot->internal->flags & FT_GLYPH_OWN_GZIP_SVG )
+ {
+ FT_SVG_Document doc = (FT_SVG_Document)slot->other;
+
+ FT_FREE( doc->svg_document );
+
+ slot->internal->flags &= ~FT_GLYPH_OWN_GZIP_SVG;
+ }
+
+ FT_FREE( slot->other );
+ }
+#endif
+
if ( clazz->done_slot )
clazz->done_slot( slot );
@@ -952,11 +1002,21 @@
FT_AutoHinter_Interface hinting;
- /* try to load embedded bitmaps first if available */
- /* */
- /* XXX: This is really a temporary hack that should disappear */
- /* promptly with FreeType 2.1! */
- /* */
+ /* XXX: The use of the `FT_LOAD_XXX_ONLY` flags is not very */
+ /* elegant. */
+
+ /* try to load SVG documents if available */
+ if ( FT_HAS_SVG( face ) )
+ {
+ error = driver->clazz->load_glyph( slot, face->size,
+ glyph_index,
+ load_flags | FT_LOAD_SVG_ONLY );
+
+ if ( !error && slot->format == FT_GLYPH_FORMAT_SVG )
+ goto Load_Ok;
+ }
+
+ /* try to load embedded bitmaps if available */
if ( FT_HAS_FIXED_SIZES( face ) &&
( load_flags & FT_LOAD_NO_BITMAP ) == 0 )
{
--- a/src/cache/ftcbasic.c
+++ b/src/cache/ftcbasic.c
@@ -183,7 +183,8 @@
if ( !error )
{
if ( face->glyph->format == FT_GLYPH_FORMAT_BITMAP ||
- face->glyph->format == FT_GLYPH_FORMAT_OUTLINE )
+ face->glyph->format == FT_GLYPH_FORMAT_OUTLINE ||
+ face->glyph->format == FT_GLYPH_FORMAT_SVG )
{
/* ok, copy it */
FT_Glyph glyph;
--- a/src/sfnt/rules.mk
+++ b/src/sfnt/rules.mk
@@ -36,6 +36,7 @@
$(SFNT_DIR)/ttbdf.c \
$(SFNT_DIR)/ttcmap.c \
$(SFNT_DIR)/ttcolr.c \
+ $(SFNT_DIR)/ttsvg.c \
$(SFNT_DIR)/ttcpal.c \
$(SFNT_DIR)/ttkern.c \
$(SFNT_DIR)/ttload.c \
--- a/src/sfnt/sfdriver.c
+++ b/src/sfnt/sfdriver.c
@@ -36,6 +36,10 @@
#include "ttcpal.h"
#endif
+#ifdef FT_CONFIG_OPTION_SVG
+#include "ttsvg.h"
+#endif
+
#ifdef TT_CONFIG_OPTION_POSTSCRIPT_NAMES
#include "ttpost.h"
#endif
@@ -1214,6 +1218,12 @@
#define PUT_COLOR_LAYERS( a ) NULL
#endif
+#ifdef FT_CONFIG_OPTION_SVG
+#define PUT_SVG_SUPPORT( a ) a
+#else
+#define PUT_SVG_SUPPORT( a ) NULL
+#endif
+
#define PUT_COLOR_LAYERS_V1( a ) PUT_COLOR_LAYERS( a )
#ifdef TT_CONFIG_OPTION_POSTSCRIPT_NAMES
@@ -1308,7 +1318,14 @@
tt_face_get_metrics, /* TT_Get_Metrics_Func get_metrics */
tt_face_get_name, /* TT_Get_Name_Func get_name */
- sfnt_get_name_id /* TT_Get_Name_ID_Func get_name_id */
+ sfnt_get_name_id, /* TT_Get_Name_ID_Func get_name_id */
+
+ PUT_SVG_SUPPORT( tt_face_load_svg ),
+ /* TT_Load_Table_Func load_svg */
+ PUT_SVG_SUPPORT( tt_face_free_svg ),
+ /* TT_Free_Table_Func free_svg */
+ PUT_SVG_SUPPORT( tt_face_load_svg_doc )
+ /* TT_Load_Svg_Doc_Func load_svg_doc */
)
--- a/src/sfnt/sfnt.c
+++ b/src/sfnt/sfnt.c
@@ -27,6 +27,7 @@
#include "ttcmap.c"
#include "ttcolr.c"
#include "ttcpal.c"
+#include "ttsvg.c"
#include "ttkern.c"
#include "ttload.c"
--- a/src/sfnt/sfobjs.c
+++ b/src/sfnt/sfobjs.c
@@ -996,6 +996,10 @@
LOAD_( colr );
}
+ /* OpenType-SVG glyph support */
+ if ( sfnt->load_svg )
+ LOAD_( svg );
+
/* consider the pclt, kerning, and gasp tables as optional */
LOAD_( pclt );
LOAD_( gasp );
@@ -1416,6 +1420,12 @@
sfnt->free_cpal( face );
sfnt->free_colr( face );
}
+
+#ifdef FT_CONFIG_OPTION_SVG
+ /* free SVG data */
+ if ( sfnt->free_svg )
+ sfnt->free_svg( face );
+#endif
}
#ifdef TT_CONFIG_OPTION_BDF
--- /dev/null
+++ b/src/sfnt/ttsvg.c
@@ -1,0 +1,386 @@
+/****************************************************************************
+ *
+ * ttsvg.c
+ *
+ * OpenType SVG Color (specification).
+ *
+ * Copyright (C) 2022 by
+ * David Turner, Robert Wilhelm, Werner Lemberg, and Moazin Khatti.
+ *
+ * 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.
+ *
+ */
+
+
+ /**************************************************************************
+ *
+ * 'SVG' table specification:
+ *
+ * https://docs.microsoft.com/en-us/typography/opentype/spec/svg
+ *
+ */
+
+#include <ft2build.h>
+#include <freetype/internal/ftstream.h>
+#include <freetype/internal/ftobjs.h>
+#include <freetype/internal/ftdebug.h>
+#include <freetype/tttags.h>
+#include <freetype/ftgzip.h>
+#include <freetype/otsvg.h>
+
+
+#ifdef FT_CONFIG_OPTION_SVG
+
+#include "ttsvg.h"
+
+
+ typedef struct Svg_
+ {
+ FT_UShort version; /* table version (starting at 0) */
+ FT_UShort num_entries; /* number of SVG document records */
+
+ FT_Byte* svg_doc_list; /* pointer to the start of SVG Document List */
+
+ void* table; /* memory that backs up SVG */
+ FT_ULong table_size;
+
+ } Svg;
+
+
+ /**************************************************************************
+ *
+ * The macro FT_COMPONENT is used in trace mode. It is an implicit
+ * parameter of the FT_TRACE() and FT_ERROR() macros, usued to print/log
+ * messages during execution.
+ */
+#undef FT_COMPONENT
+#define FT_COMPONENT ttsvg
+
+
+ FT_LOCAL_DEF( FT_Error )
+ tt_face_load_svg( TT_Face face,
+ FT_Stream stream )
+ {
+ FT_Error error;
+ FT_Memory memory = face->root.memory;
+
+ FT_ULong table_size;
+ FT_Byte* table = NULL;
+ FT_Byte* p = NULL;
+ Svg* svg = NULL;
+ FT_ULong offsetToSVGDocumentList;
+
+
+ error = face->goto_table( face, TTAG_SVG, stream, &table_size );
+ if ( error )
+ goto NoSVG;
+
+ if ( FT_FRAME_EXTRACT( table_size, table ) )
+ goto NoSVG;
+
+ /* Allocate memory for the SVG object */
+ if ( FT_NEW( svg ) )
+ goto NoSVG;
+
+ p = table;
+ svg->version = FT_NEXT_USHORT( p );
+ offsetToSVGDocumentList = FT_NEXT_ULONG( p );
+
+ if ( offsetToSVGDocumentList == 0 )
+ goto InvalidTable;
+
+ svg->svg_doc_list = (FT_Byte*)( table + offsetToSVGDocumentList );
+
+ p = svg->svg_doc_list;
+ svg->num_entries = FT_NEXT_USHORT( p );
+
+ FT_TRACE3(( "version: %d\n", svg->version ));
+ FT_TRACE3(( "number of entries: %d\n", svg->num_entries ));
+
+ svg->table = table;
+ svg->table_size = table_size;
+
+ face->svg = svg;
+ face->root.face_flags |= FT_FACE_FLAG_SVG;
+
+ return FT_Err_Ok;
+
+ InvalidTable:
+ error = FT_THROW( Invalid_Table );
+
+ NoSVG:
+ FT_FRAME_RELEASE( table );
+ FT_FREE( svg );
+ face->svg = NULL;
+
+ return error;
+ }
+
+
+ FT_LOCAL_DEF( void )
+ tt_face_free_svg( TT_Face face )
+ {
+ FT_Memory memory = face->root.memory;
+ FT_Stream stream = face->root.stream;
+
+ Svg* svg = (Svg*)face->svg;
+
+
+ if ( svg )
+ {
+ FT_FRAME_RELEASE( svg->table );
+ FT_FREE( svg );
+ }
+ }
+
+
+ typedef struct Svg_doc_
+ {
+ FT_UShort start_glyph_id;
+ FT_UShort end_glyph_id;
+
+ FT_ULong offset;
+ FT_ULong length;
+
+ } Svg_doc;
+
+
+ static Svg_doc
+ extract_svg_doc( FT_Byte* stream )
+ {
+ Svg_doc doc;
+
+
+ doc.start_glyph_id = FT_NEXT_USHORT( stream );
+ doc.end_glyph_id = FT_NEXT_USHORT( stream );
+
+ doc.offset = FT_NEXT_ULONG( stream );
+ doc.length = FT_NEXT_ULONG( stream );
+
+ return doc;
+ }
+
+
+ static FT_Int
+ compare_svg_doc( Svg_doc doc,
+ FT_UInt glyph_index )
+ {
+ if ( glyph_index < doc.start_glyph_id )
+ return -1;
+ else if ( glyph_index > doc.end_glyph_id )
+ return 1;
+ else
+ return 0;
+ }
+
+
+ static FT_Error
+ find_doc( FT_Byte* stream,
+ FT_UShort num_entries,
+ FT_UInt glyph_index,
+ FT_ULong *doc_offset,
+ FT_ULong *doc_length,
+ FT_UShort *start_glyph,
+ FT_UShort *end_glyph )
+ {
+ FT_Error error;
+
+ Svg_doc start_doc;
+ Svg_doc mid_doc;
+ Svg_doc end_doc;
+
+ FT_Bool found = FALSE;
+ FT_UInt i = 0;
+
+ FT_UInt start_index = 0;
+ FT_UInt end_index = num_entries - 1;
+ FT_Int comp_res;
+
+
+ /* search algorithm */
+ if ( num_entries == 0 )
+ {
+ error = FT_THROW( Invalid_Table );
+ return error;
+ }
+
+ start_doc = extract_svg_doc( stream + start_index * 12 );
+ end_doc = extract_svg_doc( stream + end_index * 12 );
+
+ if ( ( compare_svg_doc( start_doc, glyph_index ) == -1 ) ||
+ ( compare_svg_doc( end_doc, glyph_index ) == 1 ) )
+ {
+ error = FT_THROW( Invalid_Glyph_Index );
+ return error;
+ }
+
+ while ( start_index <= end_index )
+ {
+ i = ( start_index + end_index ) / 2;
+ mid_doc = extract_svg_doc( stream + i * 12 );
+ comp_res = compare_svg_doc( mid_doc, glyph_index );
+
+ if ( comp_res == 1 )
+ {
+ start_index = i + 1;
+ start_doc = extract_svg_doc( stream + start_index * 4 );
+ }
+ else if ( comp_res == -1 )
+ {
+ end_index = i - 1;
+ end_doc = extract_svg_doc( stream + end_index * 4 );
+ }
+ else
+ {
+ found = TRUE;
+ break;
+ }
+ }
+ /* search algorithm end */
+
+ if ( found != TRUE )
+ {
+ FT_TRACE5(( "SVG glyph not found\n" ));
+ error = FT_THROW( Invalid_Glyph_Index );
+ }
+ else
+ {
+ *doc_offset = mid_doc.offset;
+ *doc_length = mid_doc.length;
+
+ *start_glyph = mid_doc.start_glyph_id;
+ *end_glyph = mid_doc.end_glyph_id;
+
+ error = FT_Err_Ok;
+ }
+
+ return error;
+ }
+
+
+ FT_LOCAL_DEF( FT_Error )
+ tt_face_load_svg_doc( FT_GlyphSlot glyph,
+ FT_UInt glyph_index )
+ {
+ FT_Byte* doc_list; /* pointer to the SVG doc list */
+ FT_UShort num_entries; /* total number of entries in doc list */
+ FT_ULong doc_offset;
+ FT_ULong doc_length;
+
+ FT_UShort start_glyph_id;
+ FT_UShort end_glyph_id;
+
+ FT_Error error = FT_Err_Ok;
+ TT_Face face = (TT_Face)glyph->face;
+ FT_Memory memory = face->root.memory;
+ Svg* svg = (Svg*)face->svg;
+
+ FT_SVG_Document svg_document = (FT_SVG_Document)glyph->other;
+
+
+ FT_ASSERT( !( svg == NULL ) );
+
+ doc_list = svg->svg_doc_list;
+ num_entries = FT_NEXT_USHORT( doc_list );
+
+ error = find_doc( doc_list, num_entries, glyph_index,
+ &doc_offset, &doc_length,
+ &start_glyph_id, &end_glyph_id );
+ if ( error != FT_Err_Ok )
+ goto Exit;
+
+ doc_list = svg->svg_doc_list; /* reset, so we can use it again */
+ doc_list = (FT_Byte*)( doc_list + doc_offset );
+
+ if ( ( doc_list[0] == 0x1F ) && ( doc_list[1] == 0x8B )
+ && ( doc_list[2] == 0x08 ) )
+ {
+#ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
+
+ FT_ULong uncomp_size;
+ FT_Byte* uncomp_buffer;
+
+
+ /*
+ * Get the size of the original document. This helps in allotting the
+ * buffer to accommodate the uncompressed version. The last 4 bytes
+ * of the compressed document are equal to the original size modulo
+ * 2^32. Since the size of SVG documents is less than 2^32 bytes we
+ * can use this accurately. The four bytes are stored in
+ * little-endian format.
+ */
+ FT_TRACE4(( "SVG document is GZIP compressed\n" ));
+ uncomp_size = (FT_ULong)doc_list[doc_length - 1] << 24 |
+ (FT_ULong)doc_list[doc_length - 2] << 16 |
+ (FT_ULong)doc_list[doc_length - 3] << 8 |
+ (FT_ULong)doc_list[doc_length - 4];
+
+ if ( FT_QALLOC( uncomp_buffer, uncomp_size ) )
+ goto Exit;
+
+ error = FT_Gzip_Uncompress( memory,
+ uncomp_buffer,
+ &uncomp_size,
+ doc_list,
+ doc_length );
+ if ( error )
+ {
+ FT_FREE( uncomp_buffer );
+ error = FT_THROW( Invalid_Table );
+ goto Exit;
+ }
+
+ glyph->internal->flags |= FT_GLYPH_OWN_GZIP_SVG;
+
+ doc_list = uncomp_buffer;
+ doc_length = uncomp_size;
+
+#else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
+
+ error = FT_THROW( Unimplemented_Feature );
+ goto Exit;
+
+#endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
+ }
+
+ svg_document->svg_document = doc_list;
+ svg_document->svg_document_length = doc_length;
+
+ svg_document->metrics = glyph->face->size->metrics;
+ svg_document->units_per_EM = glyph->face->units_per_EM;
+
+ svg_document->start_glyph_id = start_glyph_id;
+ svg_document->end_glyph_id = end_glyph_id;
+
+ svg_document->transform.xx = 0x10000;
+ svg_document->transform.xy = 0;
+ svg_document->transform.yx = 0;
+ svg_document->transform.yy = 0x10000;
+
+ svg_document->delta.x = 0;
+ svg_document->delta.y = 0;
+
+ FT_TRACE5(( "start_glyph_id: %d\n", start_glyph_id ));
+ FT_TRACE5(( "end_glyph_id: %d\n", end_glyph_id ));
+ FT_TRACE5(( "svg_document:\n" ));
+ FT_TRACE5(( " %.*s\n", (FT_UInt)doc_length, doc_list ));
+
+ glyph->other = svg_document;
+
+ Exit:
+ return error;
+ }
+
+#else /* !FT_CONFIG_OPTION_SVG */
+
+ /* ANSI C doesn't like empty source files */
+ typedef int _tt_svg_dummy;
+
+#endif /* !FT_CONFIG_OPTION_SVG */
+
+
+/* END */
--- /dev/null
+++ b/src/sfnt/ttsvg.h
@@ -1,0 +1,43 @@
+/****************************************************************************
+ *
+ * ttsvg.h
+ *
+ * OpenType SVG Color (specification).
+ *
+ * Copyright (C) 2022 by
+ * David Turner, Robert Wilhelm, Werner Lemberg, and Moazin Khatti.
+ *
+ * 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 TTSVG_H_
+#define TTSVG_H_
+
+#include <freetype/internal/ftstream.h>
+#include <freetype/internal/tttypes.h>
+
+
+FT_BEGIN_HEADER
+
+ FT_LOCAL( FT_Error )
+ tt_face_load_svg( TT_Face face,
+ FT_Stream stream );
+
+ FT_LOCAL( void )
+ tt_face_free_svg( TT_Face face );
+
+ FT_LOCAL( FT_Error )
+ tt_face_load_svg_doc( FT_GlyphSlot glyph,
+ FT_UInt glyph_index );
+
+FT_END_HEADER
+
+#endif /* TTSVG_H_ */
+
+
+/* END */