📄 ftcache.h
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* @function:
* FTC_CMapCache_New
*
* @description:
* Create a new charmap cache.
*
* @input:
* manager ::
* A handle to the cache manager.
*
* @output:
* acache ::
* A new cache handle. NULL in case of error.
*
* @return:
* FreeType error code. 0 means success.
*
* @note:
* Like all other caches, this one will be destroyed with the cache
* manager.
*
*/
FT_EXPORT( FT_Error )
FTC_CMapCache_New( FTC_Manager manager,
FTC_CMapCache *acache );
/************************************************************************
*
* @function:
* FTC_CMapCache_Lookup
*
* @description:
* Translate a character code into a glyph index, using the charmap
* cache.
*
* @input:
* cache ::
* A charmap cache handle.
*
* face_id ::
* The source face ID.
*
* cmap_index ::
* The index of the charmap in the source face.
*
* char_code ::
* The character code (in the corresponding charmap).
*
* @return:
* Glyph index. 0 means `no glyph'.
*
*/
FT_EXPORT( FT_UInt )
FTC_CMapCache_Lookup( FTC_CMapCache cache,
FTC_FaceID face_id,
FT_Int cmap_index,
FT_UInt32 char_code );
/*************************************************************************/
/* */
/* <Section> */
/* cache_subsystem */
/* */
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** IMAGE CACHE OBJECT *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************
*
* @struct:
* FTC_ImageTypeRec
*
* @description:
* A structure used to model the type of images in a glyph cache.
*
* @fields:
* face_id ::
* The face ID.
*
* width ::
* The width in pixels.
*
* height ::
* The height in pixels.
*
* flags ::
* The load flags, as in @FT_Load_Glyph.
*
*/
typedef struct FTC_ImageTypeRec_
{
FTC_FaceID face_id;
FT_Int width;
FT_Int height;
FT_Int32 flags;
} FTC_ImageTypeRec;
/*************************************************************************
*
* @type:
* FTC_ImageType
*
* @description:
* A handle to an @FTC_ImageTypeRec structure.
*
*/
typedef struct FTC_ImageTypeRec_* FTC_ImageType;
/* */
#define FTC_IMAGE_TYPE_COMPARE( d1, d2 ) \
( (d1)->face_id == (d2)->face_id && \
(d1)->width == (d2)->width && \
(d1)->flags == (d2)->flags )
#define FTC_IMAGE_TYPE_HASH( d ) \
(FT_UFast)( FTC_FACE_ID_HASH( (d)->face_id ) ^ \
( (d)->width << 8 ) ^ (d)->height ^ \
( (d)->flags << 4 ) )
/*************************************************************************/
/* */
/* <Type> */
/* FTC_ImageCache */
/* */
/* <Description> */
/* A handle to an glyph image cache object. They are designed to */
/* hold many distinct glyph images while not exceeding a certain */
/* memory threshold. */
/* */
typedef struct FTC_ImageCacheRec_* FTC_ImageCache;
/*************************************************************************/
/* */
/* <Function> */
/* FTC_ImageCache_New */
/* */
/* <Description> */
/* Creates a new glyph image cache. */
/* */
/* <Input> */
/* manager :: The parent manager for the image cache. */
/* */
/* <Output> */
/* acache :: A handle to the new glyph image cache object. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_EXPORT( FT_Error )
FTC_ImageCache_New( FTC_Manager manager,
FTC_ImageCache *acache );
/*************************************************************************/
/* */
/* <Function> */
/* FTC_ImageCache_Lookup */
/* */
/* <Description> */
/* Retrieves a given glyph image from a glyph image cache. */
/* */
/* <Input> */
/* cache :: A handle to the source glyph image cache. */
/* */
/* type :: A pointer to a glyph image type descriptor. */
/* */
/* gindex :: The glyph index to retrieve. */
/* */
/* <Output> */
/* aglyph :: The corresponding @FT_Glyph object. 0 in case of */
/* failure. */
/* */
/* anode :: Used to return the address of of the corresponding cache */
/* node after incrementing its reference count (see note */
/* below). */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
/* <Note> */
/* 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! */
/* */
FT_EXPORT( FT_Error )
FTC_ImageCache_Lookup( FTC_ImageCache cache,
FTC_ImageType type,
FT_UInt gindex,
FT_Glyph *aglyph,
FTC_Node *anode );
/*************************************************************************/
/* */
/* <Function> */
/* FTC_ImageCache_LookupScaler */
/* */
/* <Description> */
/* A variant of @FTC_ImageCache_Lookup that uses an @FTC_ScalerRec */
/* to specify the face ID and its size. */
/* */
/* <Input> */
/* cache :: A handle to the source glyph image cache. */
/* */
/* scaler :: A pointer to a scaler descriptor. */
/* */
/* load_flags :: The corresponding load flags. */
/* */
/* gindex :: The glyph index to retrieve. */
/* */
/* <Output> */
/* aglyph :: The corresponding @FT_Glyph object. 0 in case of */
/* failure. */
/* */
/* anode :: Used to return the address of of the corresponding */
/* cache node after incrementing its reference count */
/* (see note below). */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
/* <Note> */
/* 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! */
/* */
FT_EXPORT( FT_Error )
FTC_ImageCache_LookupScaler( FTC_ImageCache cache,
FTC_Scaler scaler,
FT_ULong load_flags,
FT_UInt gindex,
FT_Glyph *aglyph,
FTC_Node *anode );
/*************************************************************************/
/* */
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