1 /***************************************************************************/
5 /* FreeType CharMap cache (body) */
7 /* Copyright 2000-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, */
9 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
11 /* This file is part of the FreeType project, and may only be used, */
12 /* modified, and distributed under the terms of the FreeType project */
13 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */
14 /* this file you indicate that you have read the license and */
15 /* understand and accept it fully. */
17 /***************************************************************************/
21 #include FT_FREETYPE_H
24 #include FT_INTERNAL_MEMORY_H
25 #include FT_INTERNAL_OBJECTS_H
26 #include FT_INTERNAL_DEBUG_H
32 #define FT_COMPONENT trace_cache
35 #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
37 typedef enum FTC_OldCMapType_
39 FTC_OLD_CMAP_BY_INDEX = 0,
40 FTC_OLD_CMAP_BY_ENCODING = 1,
41 FTC_OLD_CMAP_BY_ID = 2
46 typedef struct FTC_OldCMapIdRec_
51 } FTC_OldCMapIdRec, *FTC_OldCMapId;
54 typedef struct FTC_OldCMapDescRec_
67 } FTC_OldCMapDescRec, *FTC_OldCMapDesc;
69 #endif /* FT_CONFIG_OLD_INTERNALS */
72 /*************************************************************************/
74 /* Each FTC_CMapNode contains a simple array to map a range of character */
75 /* codes to equivalent glyph indices. */
77 /* For now, the implementation is very basic: Each node maps a range of */
78 /* 128 consecutive character codes to their corresponding glyph indices. */
80 /* We could do more complex things, but I don't think it is really very */
83 /*************************************************************************/
86 /* number of glyph indices / character code per node */
87 #define FTC_CMAP_INDICES_MAX 128
89 /* compute a query/node hash */
90 #define FTC_CMAP_HASH( faceid, index, charcode ) \
91 ( _FTC_FACE_ID_HASH( faceid ) + 211 * (index) + \
92 ( (charcode) / FTC_CMAP_INDICES_MAX ) )
94 /* the charmap query */
95 typedef struct FTC_CMapQueryRec_
101 } FTC_CMapQueryRec, *FTC_CMapQuery;
103 #define FTC_CMAP_QUERY( x ) ((FTC_CMapQuery)(x))
104 #define FTC_CMAP_QUERY_HASH( x ) \
105 FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->char_code )
107 /* the cmap cache node */
108 typedef struct FTC_CMapNodeRec_
113 FT_UInt32 first; /* first character in node */
114 FT_UInt16 indices[FTC_CMAP_INDICES_MAX]; /* array of glyph indices */
116 } FTC_CMapNodeRec, *FTC_CMapNode;
118 #define FTC_CMAP_NODE( x ) ( (FTC_CMapNode)( x ) )
119 #define FTC_CMAP_NODE_HASH( x ) \
120 FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->first )
122 /* if (indices[n] == FTC_CMAP_UNKNOWN), we assume that the corresponding */
123 /* glyph indices haven't been queried through FT_Get_Glyph_Index() yet */
124 #define FTC_CMAP_UNKNOWN ( (FT_UInt16)-1 )
127 /*************************************************************************/
128 /*************************************************************************/
130 /***** CHARMAP NODES *****/
132 /*************************************************************************/
133 /*************************************************************************/
136 FT_CALLBACK_DEF( void )
137 ftc_cmap_node_free( FTC_Node ftcnode,
140 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
141 FT_Memory memory = cache->memory;
148 /* initialize a new cmap node */
149 FT_CALLBACK_DEF( FT_Error )
150 ftc_cmap_node_new( FTC_Node *ftcanode,
154 FTC_CMapNode *anode = (FTC_CMapNode*)ftcanode;
155 FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
157 FT_Memory memory = cache->memory;
158 FTC_CMapNode node = NULL;
162 if ( !FT_NEW( node ) )
164 node->face_id = query->face_id;
165 node->cmap_index = query->cmap_index;
166 node->first = (query->char_code / FTC_CMAP_INDICES_MAX) *
167 FTC_CMAP_INDICES_MAX;
169 for ( nn = 0; nn < FTC_CMAP_INDICES_MAX; nn++ )
170 node->indices[nn] = FTC_CMAP_UNKNOWN;
178 /* compute the weight of a given cmap node */
179 FT_CALLBACK_DEF( FT_Offset )
180 ftc_cmap_node_weight( FTC_Node cnode,
186 return sizeof ( *cnode );
190 /* compare a cmap node to a given query */
191 FT_CALLBACK_DEF( FT_Bool )
192 ftc_cmap_node_compare( FTC_Node ftcnode,
195 FT_Bool* list_changed )
197 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
198 FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
203 *list_changed = FALSE;
204 if ( node->face_id == query->face_id &&
205 node->cmap_index == query->cmap_index )
207 FT_UInt32 offset = (FT_UInt32)( query->char_code - node->first );
210 return FT_BOOL( offset < FTC_CMAP_INDICES_MAX );
217 FT_CALLBACK_DEF( FT_Bool )
218 ftc_cmap_node_remove_faceid( FTC_Node ftcnode,
219 FT_Pointer ftcface_id,
221 FT_Bool* list_changed )
223 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
224 FTC_FaceID face_id = (FTC_FaceID)ftcface_id;
229 *list_changed = FALSE;
230 return FT_BOOL( node->face_id == face_id );
234 /*************************************************************************/
235 /*************************************************************************/
237 /***** GLYPH IMAGE CACHE *****/
239 /*************************************************************************/
240 /*************************************************************************/
243 FT_CALLBACK_TABLE_DEF
244 const FTC_CacheClassRec ftc_cmap_cache_class =
247 ftc_cmap_node_weight,
248 ftc_cmap_node_compare,
249 ftc_cmap_node_remove_faceid,
252 sizeof ( FTC_CacheRec ),
258 /* documentation is in ftcache.h */
260 FT_EXPORT_DEF( FT_Error )
261 FTC_CMapCache_New( FTC_Manager manager,
262 FTC_CMapCache *acache )
264 return FTC_Manager_RegisterCache( manager,
265 &ftc_cmap_cache_class,
266 FTC_CACHE_P( acache ) );
270 #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
273 * Unfortunately, it is not possible to support binary backwards
274 * compatibility in the cmap cache. The FTC_CMapCache_Lookup signature
275 * changes were too deep, and there is no clever hackish way to detect
276 * what kind of structure we are being passed.
278 * On the other hand it seems that no production code is using this
279 * function on Unix distributions.
285 /* documentation is in ftcache.h */
287 FT_EXPORT_DEF( FT_UInt )
288 FTC_CMapCache_Lookup( FTC_CMapCache cmap_cache,
291 FT_UInt32 char_code )
293 FTC_Cache cache = FTC_CACHE( cmap_cache );
294 FTC_CMapQueryRec query;
299 FT_Int no_cmap_change = 0;
302 if ( cmap_index < 0 )
304 /* Treat a negative cmap index as a special value, meaning that you */
305 /* don't want to change the FT_Face's character map through this */
306 /* call. This can be useful if the face requester callback already */
307 /* sets the face's charmap to the appropriate value. */
315 FT_TRACE0(( "FTC_CMapCache_Lookup: bad arguments, returning 0\n" ));
319 #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
322 * If cmap_index is greater than the maximum number of cachable
323 * charmaps, we assume the request is from a legacy rogue client
324 * using old internal header. See include/config/ftoption.h.
326 if ( cmap_index > FT_MAX_CHARMAP_CACHEABLE && !no_cmap_change )
328 FTC_OldCMapDesc desc = (FTC_OldCMapDesc) face_id;
331 char_code = (FT_UInt32)cmap_index;
332 query.face_id = desc->face_id;
335 switch ( desc->type )
337 case FTC_OLD_CMAP_BY_INDEX:
338 query.cmap_index = desc->u.index;
339 query.char_code = (FT_UInt32)cmap_index;
342 case FTC_OLD_CMAP_BY_ENCODING:
347 error = FTC_Manager_LookupFace( cache->manager, desc->face_id,
352 FT_Select_Charmap( face, desc->u.encoding );
354 return FT_Get_Char_Index( face, char_code );
363 #endif /* FT_CONFIG_OPTION_OLD_INTERNALS */
366 query.face_id = face_id;
367 query.cmap_index = (FT_UInt)cmap_index;
368 query.char_code = char_code;
371 hash = FTC_CMAP_HASH( face_id, cmap_index, char_code );
374 FTC_CACHE_LOOKUP_CMP( cache, ftc_cmap_node_compare, hash, &query,
377 error = FTC_Cache_Lookup( cache, hash, &query, &node );
382 FT_ASSERT( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first ) <
383 FTC_CMAP_INDICES_MAX );
385 /* something rotten can happen with rogue clients */
386 if ( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first >=
387 FTC_CMAP_INDICES_MAX ) )
388 return 0; /* XXX: should return appropriate error */
390 gindex = FTC_CMAP_NODE( node )->indices[char_code -
391 FTC_CMAP_NODE( node )->first];
392 if ( gindex == FTC_CMAP_UNKNOWN )
399 error = FTC_Manager_LookupFace( cache->manager,
400 FTC_CMAP_NODE( node )->face_id,
405 #ifdef FT_MAX_CHARMAP_CACHEABLE
406 /* something rotten can happen with rogue clients */
407 if ( cmap_index > FT_MAX_CHARMAP_CACHEABLE )
408 return 0; /* XXX: should return appropriate error */
411 if ( (FT_UInt)cmap_index < (FT_UInt)face->num_charmaps )
413 FT_CharMap old, cmap = NULL;
417 cmap = face->charmaps[cmap_index];
419 if ( old != cmap && !no_cmap_change )
420 FT_Set_Charmap( face, cmap );
422 gindex = FT_Get_Char_Index( face, char_code );
424 if ( old != cmap && !no_cmap_change )
425 FT_Set_Charmap( face, old );
428 FTC_CMAP_NODE( node )->indices[char_code -
429 FTC_CMAP_NODE( node )->first]