/***************************************************************************//*                                                                         *//*  ftcglyph.h                                                             *//*                                                                         *//*    FreeType abstract glyph cache (specification).                       *//*                                                                         *//*  Copyright 2000-2001, 2003, 2004 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.                                        *//*                                                                         *//***************************************************************************/  /*   *   *  FTC_GCache is an _abstract_ cache object optimized to store glyph   *  data.  It works as follows:   *   *   - It manages FTC_GNode objects. Each one of them can hold one or more   *     glyph `items'.  Item types are not specified in the FTC_GCache but   *     in classes that extend it.   *   *   - Glyph attributes, like face ID, character size, render mode, etc.,   *     can be grouped into abstract `glyph families'.  This avoids storing   *     the attributes within the FTC_GCache, since it is likely that many   *     FTC_GNodes will belong to the same family in typical uses.   *   *   - Each FTC_GNode is thus an FTC_Node with two additional fields:   *   *       * gindex: A glyph index, or the first index in a glyph range.   *       * family: A pointer to a glyph `family'.   *   *   - Family types are not fully specific in the FTC_Family type, but   *     by classes that extend it.   *   *  Note that both FTC_ImageCache and FTC_SBitCache extend FTC_GCache.   *  They share an FTC_Family sub-class called FTC_BasicFamily which is   *  used to store the following data: face ID, pixel/point sizes, load   *  flags.  For more details see the file `src/cache/ftcbasic.c'.   *   *  Client applications can extend FTC_GNode with their own FTC_GNode   *  and FTC_Family sub-classes to implement more complex caches (e.g.,   *  handling automatic synthesis, like obliquing & emboldening, colored   *  glyphs, etc.).   *   *  See also the FTC_ICache & FTC_SCache classes in `ftcimage.h' and   *  `ftcsbits.h', which both extend FTC_GCache with additional   *  optimizations.   *   *  A typical FTC_GCache implementation must provide at least the   *  following:   *   *  - FTC_GNode sub-class, e.g. MyNode, with relevant methods:   *        my_node_new            (must call FTC_GNode_Init)   *        my_node_free           (must call FTC_GNode_Done)   *        my_node_compare        (must call FTC_GNode_Compare)   *        my_node_remove_faceid  (must call ftc_gnode_unselect in case   *                                of match)   *   *  - FTC_Family sub-class, e.g. MyFamily, with relevant methods:   *        my_family_compare   *        my_family_init   *        my_family_reset (optional)   *        my_family_done   *   *  - FTC_GQuery sub-class, e.g. MyQuery, to hold cache-specific query   *    data.   *   *  - Constant structures for a FTC_GNodeClass.   *   *  - MyCacheNew() can be implemented easily as a call to the convenience   *    function FTC_GCache_New.   *   *  - MyCacheLookup with a call to FTC_GCache_Lookup.  This function will   *    automatically:   *   *    - Search for the corresponding family in the cache, or create   *      a new one if necessary.  Put it in FTC_GQUERY(myquery).family   *   *    - Call FTC_Cache_Lookup.   *   *    If it returns NULL, you should create a new node, then call   *    ftc_cache_add as usual.   */  /*************************************************************************/  /*                                                                       */  /* Important: The functions defined in this file are only used to        */  /*            implement an abstract glyph cache class.  You need to      */  /*            provide additional logic to implement a complete cache.    */  /*                                                                       */  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*********                                                       *********/  /*********             WARNING, THIS IS BETA CODE.               *********/  /*********                                                       *********/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/  /*************************************************************************/#ifndef __FTCGLYPH_H__#define __FTCGLYPH_H__#include <ft2build.h>#include FT_CACHE_INTERNAL_MANAGER_HFT_BEGIN_HEADER /*  *  We can group glyphs into `families'.  Each family correspond to a  *  given face ID, character size, transform, etc.  *  *  Families are implemented as MRU list nodes.  They are  *  reference-counted.  */  typedef struct  FTC_FamilyRec_  {    FTC_MruNodeRec    mrunode;    FT_UInt           num_nodes; /* current number of nodes in this family */    FTC_Cache         cache;    FTC_MruListClass  clazz;  } FTC_FamilyRec, *FTC_Family;#define  FTC_FAMILY(x)    ( (FTC_Family)(x) )#define  FTC_FAMILY_P(x)  ( (FTC_Family*)(x) )  typedef struct  FTC_GNodeRec_  {    FTC_NodeRec      node;    FTC_Family       family;    FT_UInt          gindex;  } FTC_GNodeRec, *FTC_GNode;#define FTC_GNODE( x )    ( (FTC_GNode)(x) )#define FTC_GNODE_P( x )  ( (FTC_GNode*)(x) )  typedef struct  FTC_GQueryRec_  {    FT_UInt      gindex;    FTC_Family   family;  } FTC_GQueryRec, *FTC_GQuery;#define FTC_GQUERY( x )  ( (FTC_GQuery)(x) )  /*************************************************************************/  /*                                                                       */  /* These functions are exported so that they can be called from          */  /* user-provided cache classes; otherwise, they are really part of the   */  /* cache sub-system internals.                                           */  /*                                                                       */  /* must be called by derived FTC_Node_InitFunc routines */  FT_EXPORT( void )  FTC_GNode_Init( FTC_GNode   node,                  FT_UInt     gindex,  /* glyph index for node */                  FTC_Family  family );  /* returns TRUE iff the query's glyph index correspond to the node;  */  /* this assumes that the "family" and "hash" fields of the query are */  /* already correctly set                                             */  FT_EXPORT( FT_Bool )  FTC_GNode_Compare( FTC_GNode   gnode,                     FTC_GQuery  gquery );  /* call this function to clear a node's family -- this is necessary */  /* to implement the `node_remove_faceid' cache method correctly     */  FT_EXPORT( void )  FTC_GNode_UnselectFamily( FTC_GNode  gnode,                            FTC_Cache  cache );  /* must be called by derived FTC_Node_DoneFunc routines */  FT_EXPORT( void )  FTC_GNode_Done( FTC_GNode  node,                  FTC_Cache  cache );  FT_EXPORT( void )  FTC_Family_Init( FTC_Family  family,                   FTC_Cache   cache );  typedef struct FTC_GCacheRec_  {    FTC_CacheRec    cache;    FTC_MruListRec  families;  } FTC_GCacheRec, *FTC_GCache;#define FTC_GCACHE( x )  ((FTC_GCache)(x))  /* can be used as @FTC_Cache_InitFunc */  FT_EXPORT( FT_Error )  FTC_GCache_Init( FTC_GCache  cache );  /* can be used as @FTC_Cache_DoneFunc */  FT_EXPORT( void )  FTC_GCache_Done( FTC_GCache  cache );  /* the glyph cache class adds fields for the family implementation */  typedef struct  FTC_GCacheClassRec_  {    FTC_CacheClassRec  clazz;    FTC_MruListClass   family_class;  } FTC_GCacheClassRec;  typedef const FTC_GCacheClassRec*   FTC_GCacheClass;#define FTC_GCACHE_CLASS( x )  ((FTC_GCacheClass)(x))#define FTC_CACHE__GCACHE_CLASS( x ) \          FTC_GCACHE_CLASS( FTC_CACHE(x)->org_class )#define FTC_CACHE__FAMILY_CLASS( x ) \          ( (FTC_MruListClass)FTC_CACHE__GCACHE_CLASS( x )->family_class )  /* convenience function; use it instead of FTC_Manager_Register_Cache */  FT_EXPORT( FT_Error )  FTC_GCache_New( FTC_Manager       manager,                  FTC_GCacheClass   clazz,                  FTC_GCache       *acache );  FT_EXPORT( FT_Error )  FTC_GCache_Lookup( FTC_GCache   cache,                     FT_UInt32    hash,                     FT_UInt      gindex,                     FTC_GQuery   query,                     FTC_Node    *anode );  /* */#define FTC_FAMILY_FREE( family, cache )                      \          FTC_MruList_Remove( &FTC_GCACHE((cache))->families, \                              (FTC_MruNode)(family) )#ifdef FTC_INLINE#define FTC_GCACHE_LOOKUP_CMP( cache, famcmp, nodecmp, hash,                \                               gindex, query, node, error )                 \  FT_BEGIN_STMNT                                                            \    FTC_GCache               _gcache   = FTC_GCACHE( cache );               \    FTC_GQuery               _gquery   = (FTC_GQuery)( query );             \    FTC_MruNode_CompareFunc  _fcompare = (FTC_MruNode_CompareFunc)(famcmp); \                                                                            \                                                                            \    _gquery->gindex = (gindex);                                             \                                                                            \    FTC_MRULIST_LOOKUP_CMP( &_gcache->families, _gquery, _fcompare,         \                            _gquery->family, error );                       \    if ( !error )                                                           \    {                                                                       \      FTC_Family  _gqfamily = _gquery->family;                              \                                                                            \                                                                            \      _gqfamily->num_nodes++;                                               \                                                                            \      FTC_CACHE_LOOKUP_CMP( cache, nodecmp, hash, query, node, error );     \                                                                            \      if ( --_gqfamily->num_nodes == 0 )                                    \        FTC_FAMILY_FREE( _gqfamily, _gcache );                              \    }                                                                       \  FT_END_STMNT  /* */#else /* !FTC_INLINE */#define FTC_GCACHE_LOOKUP_CMP( cache, famcmp, nodecmp, hash,               \                               gindex, query, node, error )                \   FT_BEGIN_STMNT                                                          \     error = FTC_GCache_Lookup( FTC_GCACHE( cache ), hash, gindex,         \                                FTC_GQUERY( query ), (FTC_Node*)&(node) ); \   FT_END_STMNT#endif /* !FTC_INLINE */FT_END_HEADER#endif /* __FTCGLYPH_H__ *//* END */