/src/freetype/src/cache/ftcmanag.h
https://bitbucket.org/cabalistic/ogredeps/ · C++ Header · 175 lines · 49 code · 36 blank · 90 comment · 14 complexity · d2b821d9df8cce9181f3da50239874a4 MD5 · raw file
- /***************************************************************************/
- /* */
- /* ftcmanag.h */
- /* */
- /* FreeType Cache Manager (specification). */
- /* */
- /* Copyright 2000-2001, 2003, 2004, 2006, 2010 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. */
- /* */
- /***************************************************************************/
- /*************************************************************************/
- /* */
- /* A cache manager is in charge of the following: */
- /* */
- /* - Maintain a mapping between generic FTC_FaceIDs and live FT_Face */
- /* objects. The mapping itself is performed through a user-provided */
- /* callback. However, the manager maintains a small cache of FT_Face */
- /* and FT_Size objects in order to speed up things considerably. */
- /* */
- /* - Manage one or more cache objects. Each cache is in charge of */
- /* holding a varying number of `cache nodes'. Each cache node */
- /* represents a minimal amount of individually accessible cached */
- /* data. For example, a cache node can be an FT_Glyph image */
- /* containing a vector outline, or some glyph metrics, or anything */
- /* else. */
- /* */
- /* Each cache node has a certain size in bytes that is added to the */
- /* total amount of `cache memory' within the manager. */
- /* */
- /* All cache nodes are located in a global LRU list, where the oldest */
- /* node is at the tail of the list. */
- /* */
- /* Each node belongs to a single cache, and includes a reference */
- /* count to avoid destroying it (due to caching). */
- /* */
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /********* *********/
- /********* WARNING, THIS IS BETA CODE. *********/
- /********* *********/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- /*************************************************************************/
- #ifndef __FTCMANAG_H__
- #define __FTCMANAG_H__
- #include <ft2build.h>
- #include FT_CACHE_H
- #include "ftcmru.h"
- #include "ftccache.h"
- FT_BEGIN_HEADER
- /*************************************************************************/
- /* */
- /* <Section> */
- /* cache_subsystem */
- /* */
- /*************************************************************************/
- #define FTC_MAX_FACES_DEFAULT 2
- #define FTC_MAX_SIZES_DEFAULT 4
- #define FTC_MAX_BYTES_DEFAULT 200000L /* ~200kByte by default */
- /* maximum number of caches registered in a single manager */
- #define FTC_MAX_CACHES 16
- typedef struct FTC_ManagerRec_
- {
- FT_Library library;
- FT_Memory memory;
- FTC_Node nodes_list;
- FT_ULong max_weight;
- FT_ULong cur_weight;
- FT_UInt num_nodes;
- FTC_Cache caches[FTC_MAX_CACHES];
- FT_UInt num_caches;
- FTC_MruListRec faces;
- FTC_MruListRec sizes;
- FT_Pointer request_data;
- FTC_Face_Requester request_face;
- } FTC_ManagerRec;
- /*************************************************************************/
- /* */
- /* <Function> */
- /* FTC_Manager_Compress */
- /* */
- /* <Description> */
- /* 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). */
- /* */
- /* <InOut> */
- /* manager :: A handle to the cache manager. */
- /* */
- /* <Note> */
- /* 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. */
- /* */
- FT_LOCAL( void )
- FTC_Manager_Compress( FTC_Manager manager );
- /* try to flush `count' old nodes from the cache; return the number
- * of really flushed nodes
- */
- FT_LOCAL( FT_UInt )
- FTC_Manager_FlushN( FTC_Manager manager,
- FT_UInt count );
- /* this must be used internally for the moment */
- FT_LOCAL( FT_Error )
- FTC_Manager_RegisterCache( FTC_Manager manager,
- FTC_CacheClass clazz,
- FTC_Cache *acache );
- /* */
- #define FTC_SCALER_COMPARE( a, b ) \
- ( (a)->face_id == (b)->face_id && \
- (a)->width == (b)->width && \
- (a)->height == (b)->height && \
- ((a)->pixel != 0) == ((b)->pixel != 0) && \
- ( (a)->pixel || \
- ( (a)->x_res == (b)->x_res && \
- (a)->y_res == (b)->y_res ) ) )
- #define FTC_SCALER_HASH( q ) \
- ( _FTC_FACE_ID_HASH( (q)->face_id ) + \
- (q)->width + (q)->height*7 + \
- ( (q)->pixel ? 0 : ( (q)->x_res*33 ^ (q)->y_res*61 ) ) )
- /* */
- FT_END_HEADER
- #endif /* __FTCMANAG_H__ */
- /* END */