libraries/freetype-2.0.5/include/freetype/cache/ftcglyph.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ftcglyph.h                                                             */
   4 /*                                                                         */
   5 /*    FreeType abstract glyph cache (specification).                       */
   6 /*                                                                         */
   7 /*  Copyright 2000-2001 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   /* Important: The functions defined in this file are only used to        */
  22   /*            implement an abstract glyph cache class.  You need to      */
  23   /*            provide additional logic to implement a complete cache.    */
  24   /*            For example, see `ftcimage.h' and `ftcimage.c' which       */
  25   /*            implement a FT_Glyph cache based on this code.             */
  26   /*                                                                       */
  27   /*  NOTE: For now, each glyph set is implemented as a static hash table. */
  28   /*        It would be interesting to experiment with dynamic hashes to   */
  29   /*        see whether this improves performance or not (I don't know why */
  30   /*        but something tells me it won't).                              */
  31   /*                                                                       */
  32   /*        In all cases, this change should not affect any derived glyph  */
  33   /*        cache class.                                                   */
  34   /*                                                                       */
  35   /*************************************************************************/
  36
  37
  38   /*************************************************************************/
  39   /*************************************************************************/
  40   /*************************************************************************/
  41   /*************************************************************************/
  42   /*************************************************************************/
  43   /*********                                                       *********/
  44   /*********             WARNING, THIS IS BETA CODE.               *********/
  45   /*********                                                       *********/
  46   /*************************************************************************/
  47   /*************************************************************************/
  48   /*************************************************************************/
  49   /*************************************************************************/
  50   /*************************************************************************/
  51
  52
  53 #ifndef __FTCGLYPH_H__
  54 #define __FTCGLYPH_H__
  55
  56
  57 #include <ft2build.h>
  58 #include FT_CACHE_H
  59 #include FT_CACHE_MANAGER_H
  60
  61 #include <stddef.h>
  62
  63
  64 FT_BEGIN_HEADER
  65
  66
  67   /* maximum number of glyph sets per glyph cache; must be < 256 */
  68 #define FTC_MAX_GLYPH_SETS          16
  69 #define FTC_GSET_HASH_SIZE_DEFAULT  64
  70
  71
  72   typedef struct FTC_GlyphSetRec_*     FTC_GlyphSet;
  73   typedef struct FTC_GlyphNodeRec_*    FTC_GlyphNode;
  74   typedef struct FTC_Glyph_CacheRec_*  FTC_Glyph_Cache;
  75
  76   typedef struct  FTC_GlyphNodeRec_
  77   {
  78     FTC_CacheNodeRec  root;
  79     FTC_GlyphNode     gset_next;   /* next in glyph set's bucket list */
  80     FT_UShort         glyph_index;
  81     FT_UShort         gset_index;
  82
  83   } FTC_GlyphNodeRec;
  84
  85
  86 #define FTC_GLYPHNODE( x )             ( (FTC_GlyphNode)( x ) )
  87 #define FTC_GLYPHNODE_TO_LRUNODE( n )  ( (FT_ListNode)( n ) )
  88 #define FTC_LRUNODE_TO_GLYPHNODE( n )  ( (FTC_GlyphNode)( n ) )
  89
  90
  91   /*************************************************************************/
  92   /*                                                                       */
  93   /* Glyph set methods.                                                    */
  94   /*                                                                       */
  95
  96   typedef FT_Error
  97   (*FTC_GlyphSet_InitFunc)( FTC_GlyphSet    gset,
  98                             FT_Pointer      type );
  99
 100   typedef void
 101   (*FTC_GlyphSet_DoneFunc)( FTC_GlyphSet    gset );
 102
 103   typedef FT_Bool
 104   (*FTC_GlyphSet_CompareFunc)( FTC_GlyphSet    gset,
 105                                FT_Pointer      type );
 106
 107
 108   typedef FT_Error
 109   (*FTC_GlyphSet_NewNodeFunc)( FTC_GlyphSet    gset,
 110                                FT_UInt         gindex,
 111                                FTC_GlyphNode*  anode );
 112
 113   typedef void
 114   (*FTC_GlyphSet_DestroyNodeFunc)( FTC_GlyphNode   node,
 115                                    FTC_GlyphSet    gset );
 116
 117   typedef FT_ULong
 118   (*FTC_GlyphSet_SizeNodeFunc)( FTC_GlyphNode   node,
 119                                 FTC_GlyphSet    gset );
 120
 121
 122   typedef struct  FTC_GlyphSet_Class_
 123   {
 124     FT_UInt                       gset_byte_size;
 125
 126     FTC_GlyphSet_InitFunc         init;
 127     FTC_GlyphSet_DoneFunc         done;
 128     FTC_GlyphSet_CompareFunc      compare;
 129
 130     FTC_GlyphSet_NewNodeFunc      new_node;
 131     FTC_GlyphSet_SizeNodeFunc     size_node;
 132     FTC_GlyphSet_DestroyNodeFunc  destroy_node;
 133
 134   } FTC_GlyphSet_Class;
 135
 136
 137   typedef struct  FTC_GlyphSetRec_
 138   {
 139     FTC_Glyph_Cache      cache;
 140     FTC_Manager          manager;
 141     FT_Memory            memory;
 142     FTC_GlyphSet_Class*  clazz;
 143     FT_UInt              hash_size;
 144     FTC_GlyphNode*       buckets;
 145     FT_UInt              gset_index;  /* index in parent cache    */
 146
 147   } FTC_GlyphSetRec;
 148
 149
 150   /* the abstract glyph cache class */
 151   typedef struct  FTC_Glyph_Cache_Class_
 152   {
 153     FTC_Cache_Class      root;
 154     FTC_GlyphSet_Class*  gset_class;
 155
 156   } FTC_Glyph_Cache_Class;
 157
 158
 159   /* the abstract glyph cache object */
 160   typedef struct  FTC_Glyph_CacheRec_
 161   {
 162     FTC_CacheRec              root;
 163     FT_Lru                    gsets_lru;    /* static sets lru list */
 164     FTC_GlyphSet              last_gset;    /* small cache :-)      */
 165     FTC_GlyphSet_CompareFunc  compare;      /* useful shortcut      */
 166
 167   } FTC_Glyph_CacheRec;
 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   FT_EXPORT( void )
 178   FTC_GlyphNode_Init( FTC_GlyphNode  node,
 179                       FTC_GlyphSet   gset,
 180                       FT_UInt        gindex );
 181
 182 #define FTC_GlyphNode_Ref( n ) \
 183           FTC_CACHENODE_TO_DATA_P( &(n)->root )->ref_count++
 184
 185 #define FTC_GlyphNode_Unref( n ) \
 186           FTC_CACHENODE_TO_DATA_P( &(n)->root )->ref_count--
 187
 188
 189   FT_EXPORT( void )
 190   FTC_GlyphNode_Destroy( FTC_GlyphNode    node,
 191                          FTC_Glyph_Cache  cache );
 192
 193   FT_EXPORT( FT_Error )
 194   FTC_Glyph_Cache_Init(  FTC_Glyph_Cache  cache );
 195
 196   FT_EXPORT( void )
 197   FTC_Glyph_Cache_Done(  FTC_Glyph_Cache  cache );
 198
 199
 200   FT_EXPORT( FT_Error )
 201   FTC_GlyphSet_New( FTC_Glyph_Cache  cache,
 202                     FT_Pointer       type,
 203                     FTC_GlyphSet    *aset );
 204
 205   FT_EXPORT( FT_Error )
 206   FTC_GlyphSet_Lookup_Node( FTC_GlyphSet    gset,
 207                             FT_UInt         glyph_index,
 208                             FTC_GlyphNode  *anode );
 209
 210   FT_EXPORT( FT_Error )
 211   FTC_Glyph_Cache_Lookup( FTC_Glyph_Cache  cache,
 212                           FT_Pointer       type,
 213                           FT_UInt          gindex,
 214                           FTC_GlyphNode   *anode );
 215
 216
 217 FT_END_HEADER
 218
 219 #endif /* __FTCGLYPH_H__ */
 220
 221
 222 /* END */