typedef struct FTC_ManagerRec_*  FTC_Manager;

This object is used to cache one or more FT_Face objects, along with corresponding FT_Size objects.

  typedef struct FTC_FaceIDRec_*  FTC_FaceID;

An opaque pointer type that is used to identity face objects. The contents of such objects is application-dependent.

  typedef FT_Error
  (*FTC_Face_Requester)( FTC_FaceID  face_id,
                         FT_Library  library,
                         FT_Pointer  request_data,
                         FT_Face*    aface );

A callback function provided by client applications. It is used to translate a given FTC_FaceID into a new valid FT_Face object.

FreeType error code. 0 means success.

The face requester should not perform funny things on the returned face object, like creating a new FT_Size for it, or setting a transformation through FT_Set_Transform!

  typedef struct  FTC_FontRec_
  {
    FTC_FaceID  face_id;
    FT_UShort   pix_width;
    FT_UShort   pix_height;

  } FTC_FontRec;

A simple structure used to describe a given `font' to the cache manager. Note that a `font' is the combination of a given face with a given character size.

  typedef FTC_FontRec*  FTC_Font;

A simple handle to an FTC_FontRec structure.

  typedef struct FTC_NodeRec_*  FTC_Node;

An opaque handle to a cache node object. Each cache node is reference-counted. A node with a count of 0 might be flushed out of a full cache whenever a lookup request is performed.

If you lookup nodes, you have the ability to "acquire" them, i.e., to increment their reference count. This will prevent the node from being flushed out of the cache until you explicitly "release" it (see FTC_Node_Unref).

See also FTC_SBitCache_Lookup and FTC_ImageCache_Lookup.

  FT_EXPORT( FT_Error )
  FTC_Manager_New( FT_Library          library,
                   FT_UInt             max_faces,
                   FT_UInt             max_sizes,
                   FT_ULong            max_bytes,
                   FTC_Face_Requester  requester,
                   FT_Pointer          req_data,
                   FTC_Manager        *amanager );

Creates a new cache manager.

FreeType error code. 0 means success.

  FT_EXPORT( void )
  FTC_Manager_Reset( FTC_Manager  manager );

Empties a given cache manager. This simply gets rid of all the currently cached FT_Face and FT_Size objects within the manager.

  FT_EXPORT( void )
  FTC_Manager_Done( FTC_Manager  manager );

Destroys a given manager after emptying it.

  FT_EXPORT( FT_Error )
  FTC_Manager_LookupFace( FTC_Manager  manager,
                          FTC_FaceID   face_id,
                          FT_Face     *aface );

Retrieves the FT_Face object that corresponds to a given face ID through a cache manager.

FreeType error code. 0 means success.

The returned FT_Face object is always owned by the manager. You should never try to discard it yourself.

The FT_Face object doesn't necessarily have a current size object (i.e., face->size can be 0). If you need a specific `font size', use FTC_Manager_LookupSize instead.

Never change the face's transformation matrix (i.e., never call the FT_Set_Transform function) on a returned face! If you need to transform glyphs, do it yourself after glyph loading.

  typedef struct  FTC_ScalerRec_
  {
    FTC_FaceID  face_id;
    FT_UInt     width;
    FT_UInt     height;
    FT_Int      pixel;
    FT_UInt     x_res;
    FT_UInt     y_res;

  } FTC_ScalerRec, *FTC_Scaler;

A structure used to describe a given character size in either pixels or points to the cache manager. See FTC_Manager_LookupSize.

This type is mainly used to retrieve FT_Size objects through the cache manager.

  FT_EXPORT( FT_Error )
  FTC_Manager_LookupSize( FTC_Manager  manager,
                          FTC_Scaler   scaler,
                          FT_Size     *asize );

Retrieve the FT_Size object that corresponds to a given ?FTC_Scaler? through a cache manager.

FreeType error code. 0 means success.

The returned FT_Size object is always owned by the manager. You should never try to discard it by yourself.

You can access the parent FT_Face object simply as `size->face' if you need it. Note that this object is also owned by the manager.

  FT_EXPORT( void )
  FTC_Node_Unref( FTC_Node     node,
                  FTC_Manager  manager );


  /* remove all nodes belonging to a given face_id */
  FT_EXPORT( void )
  FTC_Manager_RemoveFaceID( FTC_Manager  manager,
                            FTC_FaceID   face_id );

Decrement a cache node's internal reference count. When the count reaches 0, it is not destroyed but becomes eligible for subsequent cache flushes.

  typedef struct FTC_CMapCacheRec_*  FTC_CMapCache;

An opaque handle used to manager a charmap cache. This cache is to hold character codes -> glyph indices mappings.

  FT_EXPORT( FT_Error )
  FTC_CMapCache_New( FTC_Manager     manager,
                     FTC_CMapCache  *acache );

Creates a new charmap cache.

FreeType error code. 0 means success.

Like all other caches, this one will be destroyed with the cache manager.

  FT_EXPORT( FT_UInt )
  FTC_CMapCache_Lookup( FTC_CMapCache  cache,
                        FTC_CMapDesc   cmap_desc,
                        FT_UInt32      char_code );

Translates a character code into a glyph index, using the charmap cache.

Glyph index. 0 means "no glyph".

This function doesn't return FTC_Node handles, since there is no real use for them with typical uses of charmaps.

  typedef struct FTC_ImageCacheRec_*  FTC_ImageCache;

A handle to an glyph image cache object. They are designed to hold many distinct glyph images while not exceeding a certain memory threshold.

  FT_EXPORT( FT_Error )
  FTC_ImageCache_New( FTC_Manager      manager,
                      FTC_ImageCache  *acache );

Creates a new glyph image cache.

FreeType error code. 0 means success.

  FT_EXPORT( FT_Error )
  FTC_ImageCache_Lookup( FTC_ImageCache  cache,
                         FTC_ImageType   type,
                         FT_UInt         gindex,
                         FT_Glyph       *aglyph,
                         FTC_Node       *anode );

Retrieves a given glyph image from a glyph image cache.

FreeType error code. 0 means success.

The returned glyph is owned and managed by the glyph image cache. Never try to transform or discard it manually! You can however create a copy with FT_Glyph_Copy and modify the new one.

If `anode' is not NULL, it receives the address of the cache node containing the glyph image, after increasing its reference count. This ensures that the node (as well as the FT_Glyph) will always be kept in the cache until you call FTC_Node_Unref to `release' it.

If `anode' is NULL, the cache node is left unchanged, which means that the FT_Glyph could be flushed out of the cache on the next call to one of the caching sub-system APIs. Don't assume that it is persistent!

  typedef struct FTC_SBitRec_*  FTC_SBit;

A handle to a small bitmap descriptor. See the FTC_SBitRec structure for details.

  typedef struct  FTC_SBitRec_
  {
    FT_Byte   width;
    FT_Byte   height;
    FT_Char   left;
    FT_Char   top;

    FT_Byte   format;
    FT_Byte   max_grays;
    FT_Short  pitch;
    FT_Char   xadvance;
    FT_Char   yadvance;

    FT_Byte*  buffer;

  } FTC_SBitRec;

A very compact structure used to describe a small glyph bitmap.

  typedef struct FTC_SBitCacheRec_*  FTC_SBitCache;

A handle to a small bitmap cache. These are special cache objects used to store small glyph bitmaps (and anti-aliased pixmaps) in a much more efficient way than the traditional glyph image cache implemented by FTC_ImageCache.

  FT_EXPORT( FT_Error )
  FTC_SBitCache_New( FTC_Manager     manager,
                     FTC_SBitCache  *acache );

Creates a new cache to store small glyph bitmaps.

FreeType error code. 0 means success.

  FT_EXPORT( FT_Error )
  FTC_SBitCache_Lookup( FTC_SBitCache    cache,
                        FTC_ImageType    type,
                        FT_UInt          gindex,
                        FTC_SBit        *sbit,
                        FTC_Node        *anode );

Looks up a given small glyph bitmap in a given sbit cache and `lock' it to prevent its flushing from the cache until needed.

FreeType error code. 0 means success.

The small bitmap descriptor and its bit buffer are owned by the cache and should never be freed by the application. They might as well disappear from memory on the next cache lookup, so don't treat them as persistent data.

The descriptor's `buffer' field is set to 0 to indicate a missing glyph bitmap.

If `anode' is not NULL, it receives the address of the cache node containing the bitmap, after increasing its reference count. This ensures that the node (as well as the image) will always be kept in the cache until you call FTC_Node_Unref to `release' it.

If `anode' is NULL, the cache node is left unchanged, which means that the bitmap could be flushed out of the cache on the next call to one of the caching sub-system APIs. Don't assume that it is persistent!

  typedef struct FTC_CMapCacheRec_*  FTC_CMapCache;

An opaque handle used to manager a charmap cache. This cache is to hold character codes -> glyph indices mappings.

  typedef struct FTC_CMapDescRec_*  FTC_CMapDesc;

A handle to an FTC_CMapDescRec structure used to describe a given charmap in a charmap cache.

Each FTC_CMapDesc describes which charmap (of which FTC_FaceID) we want to use in FTC_CMapCache_Lookup.

  typedef enum  FTC_CMapType_
  {
    FTC_CMAP_BY_INDEX    = 0,
    FTC_CMAP_BY_ENCODING = 1,
    FTC_CMAP_BY_ID       = 2

  } FTC_CMapType;

The list of valid FTC_CMapDesc types. They indicate how we want to address a charmap within an FTC_FaceID.

  typedef struct  FTC_CMapIdRec_
  {
    FT_UInt  platform;
    FT_UInt  encoding;

  } FTC_CMapIdRec;

A short structure to identify a charmap by a (platform,encoding) pair of values.

  typedef struct  FTC_CMapDescRec_
  {
    FTC_FaceID    face_id;
    FTC_CMapType  type;

    union
    {
      FT_UInt        index;
      FT_Encoding    encoding;
      FTC_CMapIdRec  id;

    } u;

  } FTC_CMapDescRec;

A structure to describe a given charmap to FTC_CMapCache.

  FT_EXPORT( FT_Error )
  FTC_CMapCache_New( FTC_Manager     manager,
                     FTC_CMapCache  *acache );

Creates a new charmap cache.

FreeType error code. 0 means success.

Like all other caches, this one will be destroyed with the cache manager.

  FT_EXPORT( FT_UInt )
  FTC_CMapCache_Lookup( FTC_CMapCache  cache,
                        FTC_CMapDesc   cmap_desc,
                        FT_UInt32      char_code );

Translates a character code into a glyph index, using the charmap cache.

Glyph index. 0 means "no glyph".

This function doesn't return FTC_Node handles, since there is no real use for them with typical uses of charmaps.

  FT_EXPORT( void )
  FTC_Manager_Compress( FTC_Manager  manager );


  /* try to flush `count' old nodes from the cache; return the number
   * of really flushed nodes
   */
  FT_EXPORT( FT_UInt )
  FTC_Manager_FlushN( FTC_Manager  manager,
                      FT_UInt      count );


  /* this must be used internally for the moment */
  FT_EXPORT( FT_Error )
  FTC_Manager_RegisterCache( FTC_Manager      manager,
                             FTC_CacheClass   clazz,
                             FTC_Cache       *acache );

This function is used to check the state of the cache manager if its `num_bytes' field is greater than its `max_bytes' field. It will flush as many old cache nodes as possible (ignoring cache nodes with a non-zero reference count).

Client applications should not call this function directly. It is normally invoked by specific cache implementations.

The reason this function is exported is to allow client-specific cache classes.