ReactOS 0.4.15-dev-8096-ga0eec98
ftcglyph.h
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1/***************************************************************************/
2/* */
3/* ftcglyph.h */
4/* */
5/* FreeType abstract glyph cache (specification). */
6/* */
7/* Copyright 2000-2018 by */
8/* David Turner, Robert Wilhelm, and Werner Lemberg. */
9/* */
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. */
15/* */
16/***************************************************************************/
17
18
19 /*
20 *
21 * FTC_GCache is an _abstract_ cache object optimized to store glyph
22 * data. It works as follows:
23 *
24 * - It manages FTC_GNode objects. Each one of them can hold one or more
25 * glyph `items'. Item types are not specified in the FTC_GCache but
26 * in classes that extend it.
27 *
28 * - Glyph attributes, like face ID, character size, render mode, etc.,
29 * can be grouped into abstract `glyph families'. This avoids storing
30 * the attributes within the FTC_GCache, since it is likely that many
31 * FTC_GNodes will belong to the same family in typical uses.
32 *
33 * - Each FTC_GNode is thus an FTC_Node with two additional fields:
34 *
35 * * gindex: A glyph index, or the first index in a glyph range.
36 * * family: A pointer to a glyph `family'.
37 *
38 * - Family types are not fully specific in the FTC_Family type, but
39 * by classes that extend it.
40 *
41 * Note that both FTC_ImageCache and FTC_SBitCache extend FTC_GCache.
42 * They share an FTC_Family sub-class called FTC_BasicFamily which is
43 * used to store the following data: face ID, pixel/point sizes, load
44 * flags. For more details see the file `src/cache/ftcbasic.c'.
45 *
46 * Client applications can extend FTC_GNode with their own FTC_GNode
47 * and FTC_Family sub-classes to implement more complex caches (e.g.,
48 * handling automatic synthesis, like obliquing & emboldening, colored
49 * glyphs, etc.).
50 *
51 * See also the FTC_ICache & FTC_SCache classes in `ftcimage.h' and
52 * `ftcsbits.h', which both extend FTC_GCache with additional
53 * optimizations.
54 *
55 * A typical FTC_GCache implementation must provide at least the
56 * following:
57 *
58 * - FTC_GNode sub-class, e.g. MyNode, with relevant methods:
59 * my_node_new (must call FTC_GNode_Init)
60 * my_node_free (must call FTC_GNode_Done)
61 * my_node_compare (must call FTC_GNode_Compare)
62 * my_node_remove_faceid (must call ftc_gnode_unselect in case
63 * of match)
64 *
65 * - FTC_Family sub-class, e.g. MyFamily, with relevant methods:
66 * my_family_compare
67 * my_family_init
68 * my_family_reset (optional)
69 * my_family_done
70 *
71 * - FTC_GQuery sub-class, e.g. MyQuery, to hold cache-specific query
72 * data.
73 *
74 * - Constant structures for a FTC_GNodeClass.
75 *
76 * - MyCacheNew() can be implemented easily as a call to the convenience
77 * function FTC_GCache_New.
78 *
79 * - MyCacheLookup with a call to FTC_GCache_Lookup. This function will
80 * automatically:
81 *
82 * - Search for the corresponding family in the cache, or create
83 * a new one if necessary. Put it in FTC_GQUERY(myquery).family
84 *
85 * - Call FTC_Cache_Lookup.
86 *
87 * If it returns NULL, you should create a new node, then call
88 * ftc_cache_add as usual.
89 */
90
91
92 /*************************************************************************/
93 /* */
94 /* Important: The functions defined in this file are only used to */
95 /* implement an abstract glyph cache class. You need to */
96 /* provide additional logic to implement a complete cache. */
97 /* */
98 /*************************************************************************/
99
100
101 /*************************************************************************/
102 /*************************************************************************/
103 /*************************************************************************/
104 /*************************************************************************/
105 /*************************************************************************/
106 /********* *********/
107 /********* WARNING, THIS IS BETA CODE. *********/
108 /********* *********/
109 /*************************************************************************/
110 /*************************************************************************/
111 /*************************************************************************/
112 /*************************************************************************/
113 /*************************************************************************/
114
115
116#ifndef FTCGLYPH_H_
117#define FTCGLYPH_H_
118
119
120#include <ft2build.h>
121#include "ftcmanag.h"
122
123
125
126
127 /*
128 * We can group glyphs into `families'. Each family correspond to a
129 * given face ID, character size, transform, etc.
130 *
131 * Families are implemented as MRU list nodes. They are
132 * reference-counted.
133 */
134
135 typedef struct FTC_FamilyRec_
136 {
138 FT_UInt num_nodes; /* current number of nodes in this family */
141
143
144#define FTC_FAMILY(x) ( (FTC_Family)(x) )
145#define FTC_FAMILY_P(x) ( (FTC_Family*)(x) )
146
147
148 typedef struct FTC_GNodeRec_
149 {
153
155
156#define FTC_GNODE( x ) ( (FTC_GNode)(x) )
157#define FTC_GNODE_P( x ) ( (FTC_GNode*)(x) )
158
159
160 typedef struct FTC_GQueryRec_
161 {
164
166
167#define FTC_GQUERY( x ) ( (FTC_GQuery)(x) )
168
169
170 /*************************************************************************/
171 /* */
172 /* These functions are exported so that they can be called from */
173 /* user-provided cache classes; otherwise, they are really part of the */
174 /* cache sub-system internals. */
175 /* */
176
177 /* must be called by derived FTC_Node_InitFunc routines */
178 FT_LOCAL( void )
180 FT_UInt gindex, /* glyph index for node */
181 FTC_Family family );
182
183#ifdef FTC_INLINE
184
185 /* returns TRUE iff the query's glyph index correspond to the node; */
186 /* this assumes that the `family' and `hash' fields of the query are */
187 /* already correctly set */
190 FTC_GQuery gquery,
192 FT_Bool* list_changed );
193
194#endif
195
196 /* call this function to clear a node's family -- this is necessary */
197 /* to implement the `node_remove_faceid' cache method correctly */
198 FT_LOCAL( void )
201
202 /* must be called by derived FTC_Node_DoneFunc routines */
203 FT_LOCAL( void )
206
207
208 FT_LOCAL( void )
211
212 typedef struct FTC_GCacheRec_
213 {
216
218
219#define FTC_GCACHE( x ) ((FTC_GCache)(x))
220
221
222#if 0
223 /* can be used as @FTC_Cache_InitFunc */
225 FTC_GCache_Init( FTC_GCache cache );
226#endif
227
228
229#if 0
230 /* can be used as @FTC_Cache_DoneFunc */
231 FT_LOCAL( void )
232 FTC_GCache_Done( FTC_GCache cache );
233#endif
234
235
236 /* the glyph cache class adds fields for the family implementation */
237 typedef struct FTC_GCacheClassRec_
238 {
241
243
245
246#define FTC_GCACHE_CLASS( x ) ((FTC_GCacheClass)(x))
247
248#define FTC_CACHE_GCACHE_CLASS( x ) \
249 FTC_GCACHE_CLASS( FTC_CACHE(x)->org_class )
250#define FTC_CACHE_FAMILY_CLASS( x ) \
251 ( (FTC_MruListClass)FTC_CACHE_GCACHE_CLASS( x )->family_class )
252
253
254 /* convenience function; use it instead of FTC_Manager_Register_Cache */
257 FTC_GCacheClass clazz,
258 FTC_GCache *acache );
259
260#ifndef FTC_INLINE
262 FTC_GCache_Lookup( FTC_GCache cache,
264 FT_UInt gindex,
266 FTC_Node *anode );
267#endif
268
269
270 /* */
271
272
273#define FTC_FAMILY_FREE( family, cache ) \
274 FTC_MruList_Remove( &FTC_GCACHE((cache))->families, \
275 (FTC_MruNode)(family) )
276
277
278#ifdef FTC_INLINE
279
280#define FTC_GCACHE_LOOKUP_CMP( cache, famcmp, nodecmp, hash, \
281 gindex, query, node, error ) \
282 FT_BEGIN_STMNT \
283 FTC_GCache _gcache = FTC_GCACHE( cache ); \
284 FTC_GQuery _gquery = (FTC_GQuery)( query ); \
285 FTC_MruNode_CompareFunc _fcompare = (FTC_MruNode_CompareFunc)(famcmp); \
286 FTC_MruNode _mrunode; \
287 \
288 \
289 _gquery->gindex = (gindex); \
290 \
291 FTC_MRULIST_LOOKUP_CMP( &_gcache->families, _gquery, _fcompare, \
292 _mrunode, error ); \
293 _gquery->family = FTC_FAMILY( _mrunode ); \
294 if ( !error ) \
295 { \
296 FTC_Family _gqfamily = _gquery->family; \
297 \
298 \
299 _gqfamily->num_nodes++; \
300 \
301 FTC_CACHE_LOOKUP_CMP( cache, nodecmp, hash, query, node, error ); \
302 \
303 if ( --_gqfamily->num_nodes == 0 ) \
304 FTC_FAMILY_FREE( _gqfamily, _gcache ); \
305 } \
306 FT_END_STMNT
307 /* */
308
309#else /* !FTC_INLINE */
310
311#define FTC_GCACHE_LOOKUP_CMP( cache, famcmp, nodecmp, hash, \
312 gindex, query, node, error ) \
313 FT_BEGIN_STMNT \
314 \
315 error = FTC_GCache_Lookup( FTC_GCACHE( cache ), hash, gindex, \
316 FTC_GQUERY( query ), &node ); \
317 \
318 FT_END_STMNT
319
320#endif /* !FTC_INLINE */
321
322
324
325
326#endif /* FTCGLYPH_H_ */
327
328
329/* END */
FTC_GNode_Compare(FTC_GNode gnode, FTC_GQuery gquery, FTC_Cache cache, FT_Bool *list_changed)
Definition: ftcglyph.c:86
struct FTC_GNodeRec_ * FTC_GNode
FT_BEGIN_HEADER struct FTC_FamilyRec_ * FTC_Family
const FTC_GCacheClassRec * FTC_GCacheClass
Definition: ftcglyph.h:244
FTC_GCache_New(FTC_Manager manager, FTC_GCacheClass clazz, FTC_GCache *acache)
Definition: ftcglyph.c:175
struct FTC_GCacheClassRec_ FTC_GCacheClassRec
struct FTC_GNodeRec_ FTC_GNodeRec
struct FTC_GCacheRec_ * FTC_GCache
FTC_Family_Init(FTC_Family family, FTC_Cache cache)
Definition: ftcglyph.c:106
FTC_GNode_Init(FTC_GNode node, FT_UInt gindex, FTC_Family family)
Definition: ftcglyph.c:31
struct FTC_GQueryRec_ FTC_GQueryRec
FTC_GNode_UnselectFamily(FTC_GNode gnode, FTC_Cache cache)
Definition: ftcglyph.c:42
FT_BEGIN_HEADER struct FTC_FamilyRec_ FTC_FamilyRec
struct FTC_GQueryRec_ * FTC_GQuery
struct FTC_GCacheRec_ FTC_GCacheRec
FTC_GNode_Done(FTC_GNode node, FTC_Cache cache)
Definition: ftcglyph.c:55
struct FTC_MruListClassRec_ const * FTC_MruListClass
Definition: ftcmru.h:86
#define FT_LOCAL(x)
Definition: ftconfig.h:387
#define FT_END_HEADER
Definition: ftheader.h:54
#define FT_BEGIN_HEADER
Definition: ftheader.h:36
FT_BEGIN_HEADER typedef unsigned char FT_Bool
Definition: fttypes.h:108
int FT_Error
Definition: fttypes.h:300
unsigned int FT_UInt
Definition: fttypes.h:231
size_t FT_Offset
Definition: fttypes.h:324
FTC_MruListClass clazz
Definition: ftcglyph.h:140
FTC_Cache cache
Definition: ftcglyph.h:139
FT_UInt num_nodes
Definition: ftcglyph.h:138
FTC_MruNodeRec mrunode
Definition: ftcglyph.h:137
FTC_MruListClass family_class
Definition: ftcglyph.h:240
FTC_CacheClassRec clazz
Definition: ftcglyph.h:239
FTC_MruListRec families
Definition: ftcglyph.h:215
FTC_CacheRec cache
Definition: ftcglyph.h:214
FT_UInt gindex
Definition: ftcglyph.h:152
FTC_NodeRec node
Definition: ftcglyph.h:150
FTC_Family family
Definition: ftcglyph.h:151
FTC_Family family
Definition: ftcglyph.h:163
FT_UInt gindex
Definition: ftcglyph.h:162
Definition: cache.c:49
Definition: _hash_fun.h:40
Definition: dlist.c:348