Edit
kc3-lang/freetype/src/cache/ftccmap.c
Alexei Podtelezhnikov
- src/cache/ftccmap.c
-
/**************************************************************************** * * ftccmap.c * * FreeType CharMap cache (body) * * Copyright (C) 2000-2024 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * 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. * */ #include <freetype/freetype.h> #include <freetype/ftcache.h> #include "ftcmanag.h" #include <freetype/internal/ftmemory.h> #include <freetype/internal/ftobjs.h> #include <freetype/internal/ftdebug.h> #include "ftccback.h" #include "ftcerror.h" #undef FT_COMPONENT #define FT_COMPONENT cache /************************************************************************** * * Each FTC_CMapNode contains a simple array to map a range of character * codes to equivalent glyph indices. * * For now, the implementation is very basic: Each node maps a range of * 128 consecutive character codes to their corresponding glyph indices. * * We could do more complex things, but I don't think it is really very * useful. * */ /* number of glyph indices / character code per node */ #define FTC_CMAP_INDICES_MAX 128 /* compute a query/node hash */ #define FTC_CMAP_HASH( faceid, index, charcode ) \ ( FTC_FACE_ID_HASH( faceid ) + 211 * (index) + \ ( (charcode) / FTC_CMAP_INDICES_MAX ) ) /* the charmap query */ typedef struct FTC_CMapQueryRec_ { FTC_FaceID face_id; FT_UInt cmap_index; FT_UInt32 char_code; } FTC_CMapQueryRec, *FTC_CMapQuery; #define FTC_CMAP_QUERY( x ) ((FTC_CMapQuery)(x)) /* the cmap cache node */ typedef struct FTC_CMapNodeRec_ { FTC_NodeRec node; FTC_FaceID face_id; FT_UInt cmap_index; FT_UInt32 first; /* first character in node */ FT_UInt16 indices[FTC_CMAP_INDICES_MAX]; /* array of glyph indices */ } FTC_CMapNodeRec, *FTC_CMapNode; #define FTC_CMAP_NODE( x ) ( (FTC_CMapNode)( x ) ) /* if (indices[n] == FTC_CMAP_UNKNOWN), we assume that the corresponding */ /* glyph indices haven't been queried through FT_Get_Glyph_Index() yet */ #define FTC_CMAP_UNKNOWN (FT_UInt16)~0 /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** CHARMAP NODES *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ FT_CALLBACK_DEF( void ) ftc_cmap_node_free( FTC_Node ftcnode, FTC_Cache cache ) { FTC_CMapNode node = (FTC_CMapNode)ftcnode; FT_Memory memory = cache->memory; FT_FREE( node ); } /* initialize a new cmap node */ FT_CALLBACK_DEF( FT_Error ) ftc_cmap_node_new( FTC_Node *ftcanode, FT_Pointer ftcquery, FTC_Cache cache ) { FTC_CMapNode *anode = (FTC_CMapNode*)ftcanode; FTC_CMapQuery query = (FTC_CMapQuery)ftcquery; FT_Error error; FT_Memory memory = cache->memory; FTC_CMapNode node = NULL; FT_UInt nn; if ( !FT_QNEW( node ) ) { node->face_id = query->face_id; node->cmap_index = query->cmap_index; node->first = (query->char_code / FTC_CMAP_INDICES_MAX) * FTC_CMAP_INDICES_MAX; for ( nn = 0; nn < FTC_CMAP_INDICES_MAX; nn++ ) node->indices[nn] = FTC_CMAP_UNKNOWN; } *anode = node; return error; } /* compute the weight of a given cmap node */ FT_CALLBACK_DEF( FT_Offset ) ftc_cmap_node_weight( FTC_Node cnode, FTC_Cache cache ) { FT_UNUSED( cnode ); FT_UNUSED( cache ); return sizeof ( *cnode ); } /* compare a cmap node to a given query */ FT_CALLBACK_DEF( FT_Bool ) ftc_cmap_node_compare( FTC_Node ftcnode, FT_Pointer ftcquery, FTC_Cache cache, FT_Bool* list_changed ) { FTC_CMapNode node = (FTC_CMapNode)ftcnode; FTC_CMapQuery query = (FTC_CMapQuery)ftcquery; FT_UNUSED( cache ); if ( list_changed ) *list_changed = FALSE; if ( node->face_id == query->face_id && node->cmap_index == query->cmap_index ) { FT_UInt32 offset = (FT_UInt32)( query->char_code - node->first ); return FT_BOOL( offset < FTC_CMAP_INDICES_MAX ); } return 0; } FT_CALLBACK_DEF( FT_Bool ) ftc_cmap_node_remove_faceid( FTC_Node ftcnode, FT_Pointer ftcface_id, FTC_Cache cache, FT_Bool* list_changed ) { FTC_CMapNode node = (FTC_CMapNode)ftcnode; FTC_FaceID face_id = (FTC_FaceID)ftcface_id; FT_UNUSED( cache ); if ( list_changed ) *list_changed = FALSE; return FT_BOOL( node->face_id == face_id ); } /*************************************************************************/ /*************************************************************************/ /***** *****/ /***** GLYPH IMAGE CACHE *****/ /***** *****/ /*************************************************************************/ /*************************************************************************/ static const FTC_CacheClassRec ftc_cmap_cache_class = { ftc_cmap_node_new, /* FTC_Node_NewFunc node_new */ ftc_cmap_node_weight, /* FTC_Node_WeightFunc node_weight */ ftc_cmap_node_compare, /* FTC_Node_CompareFunc node_compare */ ftc_cmap_node_remove_faceid, /* FTC_Node_CompareFunc node_remove_faceid */ ftc_cmap_node_free, /* FTC_Node_FreeFunc node_free */ sizeof ( FTC_CacheRec ), ftc_cache_init, /* FTC_Cache_InitFunc cache_init */ ftc_cache_done, /* FTC_Cache_DoneFunc cache_done */ }; /* documentation is in ftcache.h */ FT_EXPORT_DEF( FT_Error ) FTC_CMapCache_New( FTC_Manager manager, FTC_CMapCache *acache ) { return FTC_Manager_RegisterCache( manager, &ftc_cmap_cache_class, FTC_CACHE_P( acache ) ); } /* documentation is in ftcache.h */ FT_EXPORT_DEF( FT_UInt ) FTC_CMapCache_Lookup( FTC_CMapCache cmap_cache, FTC_FaceID face_id, FT_Int cmap_index, FT_UInt32 char_code ) { FTC_Cache cache = FTC_CACHE( cmap_cache ); FTC_CMapQueryRec query; FTC_Node node; FT_Error error; FT_UInt gindex = 0; FT_Offset hash; FT_Int no_cmap_change = 0; if ( cmap_index < 0 ) { /* Treat a negative cmap index as a special value, meaning that you */ /* don't want to change the FT_Face's character map through this */ /* call. This can be useful if the face requester callback already */ /* sets the face's charmap to the appropriate value. */ no_cmap_change = 1; cmap_index = 0; } if ( !cache ) { FT_TRACE0(( "FTC_CMapCache_Lookup: bad arguments, returning 0\n" )); return 0; } query.face_id = face_id; query.cmap_index = (FT_UInt)cmap_index; query.char_code = char_code; hash = FTC_CMAP_HASH( face_id, (FT_UInt)cmap_index, char_code ); #if 1 FTC_CACHE_LOOKUP_CMP( cache, ftc_cmap_node_compare, hash, &query, node, error ); #else error = FTC_Cache_Lookup( cache, hash, &query, &node ); #endif if ( error ) goto Exit; FT_ASSERT( char_code - FTC_CMAP_NODE( node )->first < FTC_CMAP_INDICES_MAX ); /* something rotten can happen with rogue clients */ if ( char_code - FTC_CMAP_NODE( node )->first >= FTC_CMAP_INDICES_MAX ) return 0; /* XXX: should return appropriate error */ gindex = FTC_CMAP_NODE( node )->indices[char_code - FTC_CMAP_NODE( node )->first]; if ( gindex == FTC_CMAP_UNKNOWN ) { FT_Face face; gindex = 0; error = FTC_Manager_LookupFace( cache->manager, FTC_CMAP_NODE( node )->face_id, &face ); if ( error ) goto Exit; if ( cmap_index < face->num_charmaps ) { FT_CharMap old = face->charmap; FT_CharMap cmap = face->charmaps[cmap_index]; if ( !no_cmap_change ) face->charmap = cmap; gindex = FT_Get_Char_Index( face, char_code ); if ( !no_cmap_change ) face->charmap = old; } FTC_CMAP_NODE( node )->indices[char_code - FTC_CMAP_NODE( node )->first] = (FT_UShort)gindex; } Exit: return gindex; } /* END */