freetype/src/cache/ftccmap.c
David Turner f546bacdcf * src/sfnt/Jamfile: removing "ttcmap" from the list of sources
* src/cache/*, include/freetype/cache/*: fixing a bug after heavy
        testing. The current sources are now "release candidates" for the
        final version of the cache sub-system

        * Jamfile: updating "refdoc" target, and adding "autohint" to the
        list of modules to build. Both the autohinter and autofitter will be
        built by default. But which one will be used is determined by
        the content of "ftmodule.h"

        * src/autofit/*: much updates, but the code is still buggy as hell.
        Aargh..
2004-02-01 16:59:06 +00:00

287 lines
9.1 KiB
C

/***************************************************************************/
/* */
/* ftccmap.c */
/* */
/* FreeType CharMap cache (body) */
/* */
/* Copyright 2000-2001, 2002, 2003 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. */
/* */
/***************************************************************************/
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_CACHE_H
#include FT_CACHE_INTERNAL_MANAGER_H
#include FT_INTERNAL_MEMORY_H
#include FT_INTERNAL_DEBUG_H
#include FT_TRUETYPE_IDS_H
#include "ftcerror.h"
#undef FT_COMPONENT
#define FT_COMPONENT trace_cache
/*************************************************************************/
/* */
/* Each FTC_CMapNode contains a simple array to map a range of character */
/* codes to equivalent glyph indices. */
/* */
/* For now, the implementation is very basic: Each node maps a range of */
/* 128 consecutive character codes to their corresponding glyph indices. */
/* */
/* We could do more complex things, but I don't think it is really very */
/* useful. */
/* */
/*************************************************************************/
/* number of glyph indices / character code per node */
#define FTC_CMAP_INDICES_MAX 128
/* compute a query/node hash */
#define FTC_CMAP_HASH( faceid, index, charcode ) \
( FTC_FACE_ID_HASH( faceid ) + 211 * ( index ) + \
( (char_code) / FTC_CMAP_INDICES_MAX ) )
/* the charmap query */
typedef struct FTC_CMapQueryRec_
{
FTC_FaceID face_id;
FT_UInt cmap_index;
FT_UInt32 char_code;
} FTC_CMapQueryRec, *FTC_CMapQuery;
#define FTC_CMAP_QUERY( x ) ((FTC_CMapQuery)(x))
#define FTC_CMAP_QUERY_HASH( x ) \
FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->char_code )
/* the cmap cache node */
typedef struct FTC_CMapNodeRec_
{
FTC_NodeRec node;
FTC_FaceID face_id;
FT_UInt cmap_index;
FT_UInt32 first; /* first character in node */
FT_UInt16 indices[FTC_CMAP_INDICES_MAX]; /* array of glyph indices */
} FTC_CMapNodeRec, *FTC_CMapNode;
#define FTC_CMAP_NODE( x ) ( (FTC_CMapNode)( x ) )
#define FTC_CMAP_NODE_HASH( x ) \
FTC_CMAP_HASH( (x)->face_id, (x)->cmap_index, (x)->first )
/* if (indices[n] == FTC_CMAP_UNKNOWN), we assume that the corresponding */
/* glyph indices haven't been queried through FT_Get_Glyph_Index() yet */
#define FTC_CMAP_UNKNOWN ( (FT_UInt16)-1 )
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** CHARMAP NODES *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/* no need for specific finalizer; we use `ftc_node_done' directly */
FT_CALLBACK_DEF( void )
ftc_cmap_node_free( FTC_CMapNode node,
FTC_Cache cache )
{
FT_Memory memory = cache->memory;
FT_FREE( node );
}
/* initialize a new cmap node */
FT_CALLBACK_DEF( FT_Error )
ftc_cmap_node_new( FTC_CMapNode *anode,
FTC_CMapQuery query,
FTC_Cache cache )
{
FT_Error error;
FT_Memory memory = cache->memory;
FTC_CMapNode node;
FT_UInt nn;
if ( !FT_NEW( node ) )
{
node->face_id = query->face_id;
node->cmap_index = query->cmap_index;
node->first = (query->char_code / FTC_CMAP_INDICES_MAX) *
FTC_CMAP_INDICES_MAX;
for ( nn = 0; nn < FTC_CMAP_INDICES_MAX; nn++ )
node->indices[nn] = FTC_CMAP_UNKNOWN;
}
*anode = node;
return error;
}
/* compute the weight of a given cmap node */
FT_CALLBACK_DEF( FT_ULong )
ftc_cmap_node_weight( FTC_CMapNode cnode )
{
FT_UNUSED( cnode );
return sizeof ( *cnode );
}
/* compare a cmap node to a given query */
FT_CALLBACK_DEF( FT_Bool )
ftc_cmap_node_compare( FTC_CMapNode node,
FTC_CMapQuery query )
{
if ( node->face_id == query->face_id &&
node->cmap_index == query->cmap_index )
{
FT_UInt32 offset = (FT_UInt32)( query->char_code - node->first );
return FT_BOOL( offset < FTC_CMAP_INDICES_MAX );
}
return 0;
}
FT_CALLBACK_DEF( FT_Bool )
ftc_cmap_node_remove_faceid( FTC_CMapNode node,
FTC_FaceID face_id )
{
return FT_BOOL( node->face_id == face_id );
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GLYPH IMAGE CACHE *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
FT_CALLBACK_TABLE_DEF
const FTC_CacheClassRec ftc_cmap_cache_class =
{
(FTC_Node_NewFunc) ftc_cmap_node_new,
(FTC_Node_WeightFunc) ftc_cmap_node_weight,
(FTC_Node_CompareFunc)ftc_cmap_node_compare,
(FTC_Node_CompareFunc)ftc_cmap_node_remove_faceid,
(FTC_Node_FreeFunc) ftc_cmap_node_free,
sizeof ( FTC_CacheRec ),
(FTC_Cache_InitFunc) FTC_Cache_Init,
(FTC_Cache_DoneFunc) FTC_Cache_Done,
};
/* documentation is in ftccmap.h */
FT_EXPORT_DEF( FT_Error )
FTC_CMapCache_New( FTC_Manager manager,
FTC_CMapCache *acache )
{
return FTC_Manager_RegisterCache( manager,
&ftc_cmap_cache_class,
FTC_CACHE_P( acache ) );
}
/* documentation is in ftccmap.h */
FT_EXPORT_DEF( FT_UInt )
FTC_CMapCache_Lookup( FTC_CMapCache cmap_cache,
FTC_FaceID face_id,
FT_Int cmap_index,
FT_UInt32 char_code )
{
FTC_Cache cache = FTC_CACHE( cmap_cache );
FTC_CMapQueryRec query;
FTC_CMapNode node;
FT_Error error;
FT_UInt gindex = 0;
FT_UInt32 hash;
if ( !cache )
{
FT_ERROR(( "FTC_CMapCache_Lookup: bad arguments, returning 0!\n" ));
return 0;
}
query.face_id = face_id;
query.cmap_index = (FT_UInt)cmap_index;
query.char_code = char_code;
hash = FTC_CMAP_HASH( face_id, cmap_index, char_code );
#if 1
FTC_CACHE_LOOKUP_CMP( cache, ftc_cmap_node_compare, hash, &query,
node, error );
#else
error = FTC_Cache_Lookup( cache, hash, &query, (FTC_Node*) &node );
#endif
if ( error )
goto Exit;
FT_ASSERT( (FT_UInt)( char_code - node->first ) < FTC_CMAP_INDICES_MAX );
gindex = node->indices[char_code - node->first];
if ( gindex == FTC_CMAP_UNKNOWN )
{
FT_Face face;
gindex = 0;
error = FTC_Manager_LookupFace( cache->manager, node->face_id, &face );
if ( error )
goto Exit;
if ( (FT_UInt)cmap_index < (FT_UInt)face->num_charmaps )
{
FT_CharMap old, cmap = NULL;
old = face->charmap;
cmap = face->charmaps[cmap_index];
if ( old != cmap )
FT_Set_Charmap( face, cmap );
gindex = FT_Get_Char_Index( face, char_code );
if ( old != cmap )
FT_Set_Charmap( face, old );
}
node->indices[char_code - node->first] = gindex;
}
Exit:
return gindex;
}
/* END */