Edit
kc3-lang/freetype/src/sfnt/ttcpal.c
Werner Lemberg
- src/sfnt/ttcpal.c
-
/**************************************************************************** * * ttcpal.c * * TrueType and OpenType color palette support (body). * * Copyright (C) 2018-2020 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * Originally 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. * */ /************************************************************************** * * `CPAL' table specification: * * https://www.microsoft.com/typography/otspec/cpal.htm * */ #include <freetype/internal/ftdebug.h> #include <freetype/internal/ftstream.h> #include <freetype/tttags.h> #include <freetype/ftcolor.h> #ifdef TT_CONFIG_OPTION_COLOR_LAYERS #include "ttcpal.h" /* NOTE: These are the table sizes calculated through the specs. */ #define CPAL_V0_HEADER_BASE_SIZE 12 #define COLOR_SIZE 4 /* all data from `CPAL' not covered in FT_Palette_Data */ typedef struct Cpal_ { FT_UShort version; /* Table version number (0 or 1 supported). */ 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. */ /* The memory which backs up the `CPAL' table. */ void* table; FT_ULong table_size; } Cpal; /************************************************************************** * * 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 ttcpal FT_LOCAL_DEF( FT_Error ) tt_face_load_cpal( TT_Face face, FT_Stream stream ) { FT_Error error; FT_Memory memory = face->root.memory; FT_Byte* table = NULL; FT_Byte* p = NULL; Cpal* cpal = NULL; FT_ULong colors_offset; FT_ULong table_size; error = face->goto_table( face, TTAG_CPAL, stream, &table_size ); if ( error ) goto NoCpal; if ( table_size < CPAL_V0_HEADER_BASE_SIZE ) goto InvalidTable; if ( FT_FRAME_EXTRACT( table_size, table ) ) goto NoCpal; p = table; if ( FT_NEW( cpal ) ) goto NoCpal; cpal->version = FT_NEXT_USHORT( p ); if ( cpal->version > 1 ) goto InvalidTable; face->palette_data.num_palette_entries = FT_NEXT_USHORT( p ); face->palette_data.num_palettes = FT_NEXT_USHORT( p ); cpal->num_colors = FT_NEXT_USHORT( p ); colors_offset = FT_NEXT_ULONG( p ); if ( CPAL_V0_HEADER_BASE_SIZE + face->palette_data.num_palettes * 2U > table_size ) goto InvalidTable; if ( colors_offset >= table_size ) goto InvalidTable; if ( cpal->num_colors * COLOR_SIZE > table_size - colors_offset ) goto InvalidTable; if ( face->palette_data.num_palette_entries > cpal->num_colors ) goto InvalidTable; cpal->color_indices = p; cpal->colors = (FT_Byte*)( table + colors_offset ); if ( cpal->version == 1 ) { FT_ULong type_offset, label_offset, entry_label_offset; FT_UShort* array = NULL; FT_UShort* limit; FT_UShort* q; if ( CPAL_V0_HEADER_BASE_SIZE + face->palette_data.num_palettes * 2U + 3U * 4 > table_size ) goto InvalidTable; p += face->palette_data.num_palettes * 2; type_offset = FT_NEXT_ULONG( p ); label_offset = FT_NEXT_ULONG( p ); entry_label_offset = FT_NEXT_ULONG( p ); if ( type_offset ) { if ( type_offset >= table_size ) goto InvalidTable; if ( face->palette_data.num_palettes * 2 > table_size - type_offset ) goto InvalidTable; if ( FT_QNEW_ARRAY( array, face->palette_data.num_palettes ) ) goto NoCpal; p = table + type_offset; q = array; limit = q + face->palette_data.num_palettes; while ( q < limit ) *q++ = FT_NEXT_USHORT( p ); face->palette_data.palette_flags = array; } if ( label_offset ) { if ( label_offset >= table_size ) goto InvalidTable; if ( face->palette_data.num_palettes * 2 > table_size - label_offset ) goto InvalidTable; if ( FT_QNEW_ARRAY( array, face->palette_data.num_palettes ) ) goto NoCpal; p = table + label_offset; q = array; limit = q + face->palette_data.num_palettes; while ( q < limit ) *q++ = FT_NEXT_USHORT( p ); face->palette_data.palette_name_ids = array; } if ( entry_label_offset ) { if ( entry_label_offset >= table_size ) goto InvalidTable; if ( face->palette_data.num_palette_entries * 2 > table_size - entry_label_offset ) goto InvalidTable; if ( FT_QNEW_ARRAY( array, face->palette_data.num_palette_entries ) ) goto NoCpal; p = table + entry_label_offset; q = array; limit = q + face->palette_data.num_palette_entries; while ( q < limit ) *q++ = FT_NEXT_USHORT( p ); face->palette_data.palette_entry_name_ids = array; } } cpal->table = table; cpal->table_size = table_size; face->cpal = cpal; /* set up default palette */ if ( FT_NEW_ARRAY( face->palette, face->palette_data.num_palette_entries ) ) goto NoCpal; if ( tt_face_palette_set( face, 0 ) ) goto InvalidTable; return FT_Err_Ok; InvalidTable: error = FT_THROW( Invalid_Table ); NoCpal: FT_FRAME_RELEASE( table ); FT_FREE( cpal ); face->cpal = NULL; /* arrays in `face->palette_data' and `face->palette' */ /* are freed in `sfnt_done_face' */ return error; } FT_LOCAL_DEF( void ) tt_face_free_cpal( TT_Face face ) { FT_Stream stream = face->root.stream; FT_Memory memory = face->root.memory; Cpal* cpal = (Cpal*)face->cpal; if ( cpal ) { FT_FRAME_RELEASE( cpal->table ); FT_FREE( cpal ); } } FT_LOCAL_DEF( FT_Error ) tt_face_palette_set( TT_Face face, FT_UInt palette_index ) { Cpal* cpal = (Cpal*)face->cpal; FT_Byte* offset; FT_Byte* p; FT_Color* q; FT_Color* limit; FT_UShort color_index; if ( !cpal || palette_index >= face->palette_data.num_palettes ) return FT_THROW( Invalid_Argument ); offset = cpal->color_indices + 2 * palette_index; color_index = FT_PEEK_USHORT( offset ); if ( color_index + face->palette_data.num_palette_entries > cpal->num_colors ) return FT_THROW( Invalid_Table ); p = cpal->colors + COLOR_SIZE * color_index; q = face->palette; limit = q + face->palette_data.num_palette_entries; while ( q < limit ) { q->blue = FT_NEXT_BYTE( p ); q->green = FT_NEXT_BYTE( p ); q->red = FT_NEXT_BYTE( p ); q->alpha = FT_NEXT_BYTE( p ); q++; } return FT_Err_Ok; } #else /* !TT_CONFIG_OPTION_COLOR_LAYERS */ /* ANSI C doesn't like empty source files */ typedef int _tt_cpal_dummy; #endif /* !TT_CONFIG_OPTION_COLOR_LAYERS */ /* EOF */