diff options
Diffstat (limited to 'src/3rdparty/freetype/src/sfnt/ttsvg.c')
| -rw-r--r-- | src/3rdparty/freetype/src/sfnt/ttsvg.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/src/3rdparty/freetype/src/sfnt/ttsvg.c b/src/3rdparty/freetype/src/sfnt/ttsvg.c new file mode 100644 index 0000000000..4461d483b0 --- /dev/null +++ b/src/3rdparty/freetype/src/sfnt/ttsvg.c @@ -0,0 +1,413 @@ +/**************************************************************************** + * + * ttsvg.c + * + * OpenType SVG Color (specification). + * + * Copyright (C) 2022-2023 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" + + + /* NOTE: These table sizes are given by the specification. */ +#define SVG_TABLE_HEADER_SIZE (10U) +#define SVG_DOCUMENT_RECORD_SIZE (12U) +#define SVG_DOCUMENT_LIST_MINIMUM_SIZE (2U + SVG_DOCUMENT_RECORD_SIZE) +#define SVG_MINIMUM_SIZE (SVG_TABLE_HEADER_SIZE + \ + SVG_DOCUMENT_LIST_MINIMUM_SIZE) + + + 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 ( table_size < SVG_MINIMUM_SIZE ) + goto InvalidTable; + + 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 < SVG_TABLE_HEADER_SIZE || + offsetToSVGDocumentList > table_size - + SVG_DOCUMENT_LIST_MINIMUM_SIZE ) + 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 )); + + if ( offsetToSVGDocumentList + 2U + + svg->num_entries * SVG_DOCUMENT_RECORD_SIZE > table_size ) + goto InvalidTable; + + 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* document_records, + 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 = { 0, 0, 0, 0 }; /* pacify compiler */ + 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( document_records + start_index * 12 ); + end_doc = extract_svg_doc( document_records + 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( document_records + i * 12 ); + comp_res = compare_svg_doc( mid_doc, glyph_index ); + + if ( comp_res == 1 ) + { + start_index = i + 1; + start_doc = extract_svg_doc( document_records + start_index * 4 ); + } + else if ( comp_res == -1 ) + { + end_index = i - 1; + end_doc = extract_svg_doc( document_records + 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_Error error = FT_Err_Ok; + TT_Face face = (TT_Face)glyph->face; + FT_Memory memory = face->root.memory; + Svg* svg = (Svg*)face->svg; + + FT_Byte* doc_list; + FT_ULong doc_limit; + + FT_Byte* doc; + FT_ULong doc_offset; + FT_ULong doc_length; + FT_UShort doc_start_glyph_id; + FT_UShort doc_end_glyph_id; + + FT_SVG_Document svg_document = (FT_SVG_Document)glyph->other; + + + FT_ASSERT( !( svg == NULL ) ); + + doc_list = svg->svg_doc_list; + + error = find_doc( doc_list + 2, svg->num_entries, glyph_index, + &doc_offset, &doc_length, + &doc_start_glyph_id, &doc_end_glyph_id ); + if ( error != FT_Err_Ok ) + goto Exit; + + doc_limit = svg->table_size - + (FT_ULong)( doc_list - (FT_Byte*)svg->table ); + if ( doc_offset > doc_limit || + doc_length > doc_limit - doc_offset ) + { + error = FT_THROW( Invalid_Table ); + goto Exit; + } + + doc = doc_list + doc_offset; + + if ( doc_length > 6 && + doc[0] == 0x1F && + doc[1] == 0x8B && + doc[2] == 0x08 ) + { +#ifdef FT_CONFIG_OPTION_USE_ZLIB + + FT_ULong uncomp_size; + FT_Byte* uncomp_buffer = NULL; + + + /* + * 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[doc_length - 1] << 24 | + (FT_ULong)doc[doc_length - 2] << 16 | + (FT_ULong)doc[doc_length - 3] << 8 | + (FT_ULong)doc[doc_length - 4]; + + if ( FT_QALLOC( uncomp_buffer, uncomp_size ) ) + goto Exit; + + error = FT_Gzip_Uncompress( memory, + uncomp_buffer, + &uncomp_size, + doc, + doc_length ); + if ( error ) + { + FT_FREE( uncomp_buffer ); + error = FT_THROW( Invalid_Table ); + goto Exit; + } + + glyph->internal->flags |= FT_GLYPH_OWN_GZIP_SVG; + + doc = uncomp_buffer; + doc_length = uncomp_size; + +#else /* !FT_CONFIG_OPTION_USE_ZLIB */ + + error = FT_THROW( Unimplemented_Feature ); + goto Exit; + +#endif /* !FT_CONFIG_OPTION_USE_ZLIB */ + } + + svg_document->svg_document = doc; + 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 = doc_start_glyph_id; + svg_document->end_glyph_id = doc_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", doc_start_glyph_id )); + FT_TRACE5(( "end_glyph_id: %d\n", doc_end_glyph_id )); + FT_TRACE5(( "svg_document:\n" )); + FT_TRACE5(( " %.*s\n", (FT_UInt)doc_length, doc )); + + 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 */ |