1 /***************************************************************************/
5 /* FreeType CharMap cache (body) */
7 /* Copyright 2000-2014 by */
8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
10 /* This file is part of the FreeType project, and may only be used, */
11 /* modified, and distributed under the terms of the FreeType project */
12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13 /* this file you indicate that you have read the license and */
14 /* understand and accept it fully. */
16 /***************************************************************************/
20 #include FT_FREETYPE_H
23 #include FT_INTERNAL_MEMORY_H
24 #include FT_INTERNAL_OBJECTS_H
25 #include FT_INTERNAL_DEBUG_H
31 #define FT_COMPONENT trace_cache
34 /*************************************************************************/
36 /* Each FTC_CMapNode contains a simple array to map a range of character */
37 /* codes to equivalent glyph indices. */
39 /* For now, the implementation is very basic: Each node maps a range of */
40 /* 128 consecutive character codes to their corresponding glyph indices. */
42 /* We could do more complex things, but I don't think it is really very */
45 /*************************************************************************/
48 /* number of glyph indices / character code per node */
49 #define FTC_CMAP_INDICES_MAX 128
51 /* compute a query/node hash */
52 #define FTC_CMAP_HASH( faceid, index, charcode ) \
53 ( _FTC_FACE_ID_HASH( faceid ) + 211 * (index) + \
54 ( (charcode) / FTC_CMAP_INDICES_MAX ) )
56 /* the charmap query */
57 typedef struct FTC_CMapQueryRec_
63 } FTC_CMapQueryRec, *FTC_CMapQuery;
65 #define FTC_CMAP_QUERY( x ) ((FTC_CMapQuery)(x))
66 #define FTC_CMAP_QUERY_HASH( x ) \
67 FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->char_code )
69 /* the cmap cache node */
70 typedef struct FTC_CMapNodeRec_
75 FT_UInt32 first; /* first character in node */
76 FT_UInt16 indices[FTC_CMAP_INDICES_MAX]; /* array of glyph indices */
78 } FTC_CMapNodeRec, *FTC_CMapNode;
80 #define FTC_CMAP_NODE( x ) ( (FTC_CMapNode)( x ) )
81 #define FTC_CMAP_NODE_HASH( x ) \
82 FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->first )
84 /* if (indices[n] == FTC_CMAP_UNKNOWN), we assume that the corresponding */
85 /* glyph indices haven't been queried through FT_Get_Glyph_Index() yet */
86 #define FTC_CMAP_UNKNOWN (FT_UInt16)~0
89 /*************************************************************************/
90 /*************************************************************************/
92 /***** CHARMAP NODES *****/
94 /*************************************************************************/
95 /*************************************************************************/
98 FT_CALLBACK_DEF( void )
99 ftc_cmap_node_free( FTC_Node ftcnode,
102 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
103 FT_Memory memory = cache->memory;
110 /* initialize a new cmap node */
111 FT_CALLBACK_DEF( FT_Error )
112 ftc_cmap_node_new( FTC_Node *ftcanode,
116 FTC_CMapNode *anode = (FTC_CMapNode*)ftcanode;
117 FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
119 FT_Memory memory = cache->memory;
120 FTC_CMapNode node = NULL;
124 if ( !FT_NEW( node ) )
126 node->face_id = query->face_id;
127 node->cmap_index = query->cmap_index;
128 node->first = (query->char_code / FTC_CMAP_INDICES_MAX) *
129 FTC_CMAP_INDICES_MAX;
131 for ( nn = 0; nn < FTC_CMAP_INDICES_MAX; nn++ )
132 node->indices[nn] = FTC_CMAP_UNKNOWN;
140 /* compute the weight of a given cmap node */
141 FT_CALLBACK_DEF( FT_Offset )
142 ftc_cmap_node_weight( FTC_Node cnode,
148 return sizeof ( *cnode );
152 /* compare a cmap node to a given query */
153 FT_CALLBACK_DEF( FT_Bool )
154 ftc_cmap_node_compare( FTC_Node ftcnode,
157 FT_Bool* list_changed )
159 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
160 FTC_CMapQuery query = (FTC_CMapQuery)ftcquery;
165 *list_changed = FALSE;
166 if ( node->face_id == query->face_id &&
167 node->cmap_index == query->cmap_index )
169 FT_UInt32 offset = (FT_UInt32)( query->char_code - node->first );
172 return FT_BOOL( offset < FTC_CMAP_INDICES_MAX );
179 FT_CALLBACK_DEF( FT_Bool )
180 ftc_cmap_node_remove_faceid( FTC_Node ftcnode,
181 FT_Pointer ftcface_id,
183 FT_Bool* list_changed )
185 FTC_CMapNode node = (FTC_CMapNode)ftcnode;
186 FTC_FaceID face_id = (FTC_FaceID)ftcface_id;
191 *list_changed = FALSE;
192 return FT_BOOL( node->face_id == face_id );
196 /*************************************************************************/
197 /*************************************************************************/
199 /***** GLYPH IMAGE CACHE *****/
201 /*************************************************************************/
202 /*************************************************************************/
206 const FTC_CacheClassRec ftc_cmap_cache_class =
209 ftc_cmap_node_weight,
210 ftc_cmap_node_compare,
211 ftc_cmap_node_remove_faceid,
214 sizeof ( FTC_CacheRec ),
220 /* documentation is in ftcache.h */
222 FT_EXPORT_DEF( FT_Error )
223 FTC_CMapCache_New( FTC_Manager manager,
224 FTC_CMapCache *acache )
226 return FTC_Manager_RegisterCache( manager,
227 &ftc_cmap_cache_class,
228 FTC_CACHE_P( acache ) );
232 /* documentation is in ftcache.h */
234 FT_EXPORT_DEF( FT_UInt )
235 FTC_CMapCache_Lookup( FTC_CMapCache cmap_cache,
238 FT_UInt32 char_code )
240 FTC_Cache cache = FTC_CACHE( cmap_cache );
241 FTC_CMapQueryRec query;
246 FT_Int no_cmap_change = 0;
249 if ( cmap_index < 0 )
251 /* Treat a negative cmap index as a special value, meaning that you */
252 /* don't want to change the FT_Face's character map through this */
253 /* call. This can be useful if the face requester callback already */
254 /* sets the face's charmap to the appropriate value. */
262 FT_TRACE0(( "FTC_CMapCache_Lookup: bad arguments, returning 0\n" ));
269 query.face_id = face_id;
270 query.cmap_index = (FT_UInt)cmap_index;
271 query.char_code = char_code;
273 hash = FTC_CMAP_HASH( face_id, cmap_index, char_code );
276 FTC_CACHE_LOOKUP_CMP( cache, ftc_cmap_node_compare, hash, &query,
279 error = FTC_Cache_Lookup( cache, hash, &query, &node );
284 FT_ASSERT( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first ) <
285 FTC_CMAP_INDICES_MAX );
287 /* something rotten can happen with rogue clients */
288 if ( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first >=
289 FTC_CMAP_INDICES_MAX ) )
290 return 0; /* XXX: should return appropriate error */
292 gindex = FTC_CMAP_NODE( node )->indices[char_code -
293 FTC_CMAP_NODE( node )->first];
294 if ( gindex == FTC_CMAP_UNKNOWN )
301 error = FTC_Manager_LookupFace( cache->manager,
302 FTC_CMAP_NODE( node )->face_id,
307 if ( (FT_UInt)cmap_index < (FT_UInt)face->num_charmaps )
309 FT_CharMap old, cmap = NULL;
313 cmap = face->charmaps[cmap_index];
315 if ( old != cmap && !no_cmap_change )
316 FT_Set_Charmap( face, cmap );
318 gindex = FT_Get_Char_Index( face, char_code );
320 if ( old != cmap && !no_cmap_change )
321 FT_Set_Charmap( face, old );
324 FTC_CMAP_NODE( node )->indices[char_code -
325 FTC_CMAP_NODE( node )->first]