| /***************************************************************************/ |
| /* */ |
| /* ftcglyph.h */ |
| /* */ |
| /* FreeType abstract glyph cache (specification). */ |
| /* */ |
| /* Copyright 2000-2001 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. */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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. */ |
| /* For example, see `ftcimage.h' and `ftcimage.c' which */ |
| /* implement a FT_Glyph cache based on this code. */ |
| /* */ |
| /* NOTE: For now, each glyph set is implemented as a static hash table. */ |
| /* It would be interesting to experiment with dynamic hashes to */ |
| /* see whether this improves performance or not (I don't know why */ |
| /* but something tells me it won't). */ |
| /* */ |
| /* In all cases, this change should not affect any derived glyph */ |
| /* cache class. */ |
| /* */ |
| /*************************************************************************/ |
| |
| |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /********* *********/ |
| /********* WARNING, THIS IS BETA CODE. *********/ |
| /********* *********/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| /*************************************************************************/ |
| |
| |
| #ifndef __FTCGLYPH_H__ |
| #define __FTCGLYPH_H__ |
| |
| |
| #include <ft2build.h> |
| #include FT_CACHE_H |
| #include FT_CACHE_MANAGER_H |
| |
| #include <stddef.h> |
| |
| |
| FT_BEGIN_HEADER |
| |
| |
| /* each glyph set is characterized by a "glyph set type" which must be */ |
| /* defined by sub-classes */ |
| typedef struct FTC_GlyphFamilyRec_* FTC_GlyphFamily; |
| |
| /* handle to a glyph cache node */ |
| typedef struct FTC_GlyphNodeRec_* FTC_GlyphNode; |
| |
| |
| /* size should be 24 + chunk size on 32-bit machines; */ |
| /* note that the node's hash is ((gfam->hash << 16) | glyph_index) -- */ |
| /* this _must_ be set properly by the glyph node initializer */ |
| /* */ |
| typedef struct FTC_GlyphNodeRec_ |
| { |
| FTC_NodeRec node; |
| FT_UShort item_count; |
| FT_UShort item_start; |
| |
| } FTC_GlyphNodeRec; |
| |
| |
| #define FTC_GLYPH_NODE( x ) ( (FTC_GlyphNode)(x) ) |
| #define FTC_GLYPH_NODE_P( x ) ( (FTC_GlyphNode*)(x) ) |
| |
| |
| typedef struct FTC_GlyphQueryRec_ |
| { |
| FTC_QueryRec query; |
| FT_UInt gindex; |
| |
| } FTC_GlyphQueryRec, *FTC_GlyphQuery; |
| |
| |
| #define FTC_GLYPH_QUERY( x ) ( (FTC_GlyphQuery)(x) ) |
| |
| |
| /* a glyph set is used to categorize glyphs of a given type */ |
| typedef struct FTC_GlyphFamilyRec_ |
| { |
| FTC_FamilyRec family; |
| FT_UInt32 hash; |
| FT_UInt item_total; /* total number of glyphs in family */ |
| FT_UInt item_count; /* number of glyph items per node */ |
| |
| } FTC_GlyphFamilyRec; |
| |
| |
| #define FTC_GLYPH_FAMILY( x ) ( (FTC_GlyphFamily)(x) ) |
| #define FTC_GLYPH_FAMILY_P( x ) ( (FTC_GlyphFamily*)(x) ) |
| |
| #define FTC_GLYPH_FAMILY_MEMORY( x ) FTC_FAMILY(x)->cache->memory |
| |
| |
| /* each glyph node contains a 'chunk' of glyph items; */ |
| /* translate a glyph index into a chunk index */ |
| #define FTC_GLYPH_FAMILY_CHUNK( gfam, gindex ) \ |
| ( ( gindex ) / FTC_GLYPH_FAMILY( gfam )->item_count ) |
| |
| /* find a glyph index's chunk, and return its start index */ |
| #define FTC_GLYPH_FAMILY_START( gfam, gindex ) \ |
| ( FTC_GLYPH_FAMILY_CHUNK( gfam, gindex ) * \ |
| FTC_GLYPH_FAMILY( gfam )->item_count ) |
| |
| /* compute a glyph request's hash value */ |
| #define FTC_GLYPH_FAMILY_HASH( gfam, gindex ) \ |
| ( (FT_UFast)( \ |
| ( FTC_GLYPH_FAMILY( gfam )->hash << 16 ) | \ |
| ( FTC_GLYPH_FAMILY_CHUNK( gfam, gindex ) & 0xFFFF ) ) ) |
| |
| /* must be called in an FTC_Family_CompareFunc to update the query */ |
| /* whenever a glyph set is matched in the lookup, or when it */ |
| /* is created */ |
| #define FTC_GLYPH_FAMILY_FOUND( gfam, gquery ) \ |
| do \ |
| { \ |
| FTC_QUERY( gquery )->family = FTC_FAMILY( gfam ); \ |
| FTC_QUERY( gquery )->hash = \ |
| FTC_GLYPH_FAMILY_HASH( gfam, \ |
| FTC_GLYPH_QUERY( gquery )->gindex ); \ |
| } while ( 0 ) |
| |
| /* retrieve glyph index of glyph node */ |
| #define FTC_GLYPH_NODE_GINDEX( x ) \ |
| ( (FT_UInt)( FTC_GLYPH_NODE( x )->node.hash & 0xFFFF ) ) |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* 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_glyph_node_init( FTC_GlyphNode node, |
| FT_UInt gindex, /* glyph index for node */ |
| FTC_GlyphFamily gfam ); |
| |
| /* 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_glyph_node_compare( FTC_GlyphNode gnode, |
| FTC_GlyphQuery gquery ); |
| |
| /* must be called by derived FTC_Node_DoneFunc routines */ |
| FT_EXPORT( void ) |
| ftc_glyph_node_done( FTC_GlyphNode node, |
| FTC_Cache cache ); |
| |
| |
| /* must be called by derived FTC_Family_InitFunc; */ |
| /* calls "ftc_family_init" */ |
| FT_EXPORT( FT_Error ) |
| ftc_glyph_family_init( FTC_GlyphFamily gfam, |
| FT_UInt32 hash, |
| FT_UInt item_count, |
| FT_UInt item_total, |
| FTC_GlyphQuery gquery, |
| FTC_Cache cache ); |
| |
| FT_EXPORT( void ) |
| ftc_glyph_family_done( FTC_GlyphFamily gfam ); |
| |
| |
| /* */ |
| |
| FT_END_HEADER |
| |
| |
| #endif /* __FTCGLYPH_H__ */ |
| |
| |
| /* END */ |
