/***************************************************************************/ | |
/* */ | |
/* ftccmap.c */ | |
/* */ | |
/* FreeType CharMap cache (body) */ | |
/* */ | |
/* Copyright 2000-2015 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 "ftcmanag.h" | |
#include FT_INTERNAL_MEMORY_H | |
#include FT_INTERNAL_OBJECTS_H | |
#include FT_INTERNAL_DEBUG_H | |
#include "ftccback.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) + \ | |
( (charcode) / 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)) | |
/* 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 ) ) | |
/* 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)~0 | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** CHARMAP NODES *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
FT_CALLBACK_DEF( void ) | |
ftc_cmap_node_free( FTC_Node ftcnode, | |
FTC_Cache cache ) | |
{ | |
FTC_CMapNode node = (FTC_CMapNode)ftcnode; | |
FT_Memory memory = cache->memory; | |
FT_FREE( node ); | |
} | |
/* initialize a new cmap node */ | |
FT_CALLBACK_DEF( FT_Error ) | |
ftc_cmap_node_new( FTC_Node *ftcanode, | |
FT_Pointer ftcquery, | |
FTC_Cache cache ) | |
{ | |
FTC_CMapNode *anode = (FTC_CMapNode*)ftcanode; | |
FTC_CMapQuery query = (FTC_CMapQuery)ftcquery; | |
FT_Error error; | |
FT_Memory memory = cache->memory; | |
FTC_CMapNode node = NULL; | |
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_Offset ) | |
ftc_cmap_node_weight( FTC_Node cnode, | |
FTC_Cache cache ) | |
{ | |
FT_UNUSED( cnode ); | |
FT_UNUSED( cache ); | |
return sizeof ( *cnode ); | |
} | |
/* compare a cmap node to a given query */ | |
FT_CALLBACK_DEF( FT_Bool ) | |
ftc_cmap_node_compare( FTC_Node ftcnode, | |
FT_Pointer ftcquery, | |
FTC_Cache cache, | |
FT_Bool* list_changed ) | |
{ | |
FTC_CMapNode node = (FTC_CMapNode)ftcnode; | |
FTC_CMapQuery query = (FTC_CMapQuery)ftcquery; | |
FT_UNUSED( cache ); | |
if ( list_changed ) | |
*list_changed = FALSE; | |
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_Node ftcnode, | |
FT_Pointer ftcface_id, | |
FTC_Cache cache, | |
FT_Bool* list_changed ) | |
{ | |
FTC_CMapNode node = (FTC_CMapNode)ftcnode; | |
FTC_FaceID face_id = (FTC_FaceID)ftcface_id; | |
FT_UNUSED( cache ); | |
if ( list_changed ) | |
*list_changed = FALSE; | |
return FT_BOOL( node->face_id == face_id ); | |
} | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/***** *****/ | |
/***** GLYPH IMAGE CACHE *****/ | |
/***** *****/ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
static | |
const FTC_CacheClassRec ftc_cmap_cache_class = | |
{ | |
ftc_cmap_node_new, | |
ftc_cmap_node_weight, | |
ftc_cmap_node_compare, | |
ftc_cmap_node_remove_faceid, | |
ftc_cmap_node_free, | |
sizeof ( FTC_CacheRec ), | |
ftc_cache_init, | |
ftc_cache_done, | |
}; | |
/* documentation is in ftcache.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 ftcache.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_Node node; | |
FT_Error error; | |
FT_UInt gindex = 0; | |
FT_Offset hash; | |
FT_Int no_cmap_change = 0; | |
if ( cmap_index < 0 ) | |
{ | |
/* Treat a negative cmap index as a special value, meaning that you */ | |
/* don't want to change the FT_Face's character map through this */ | |
/* call. This can be useful if the face requester callback already */ | |
/* sets the face's charmap to the appropriate value. */ | |
no_cmap_change = 1; | |
cmap_index = 0; | |
} | |
if ( !cache ) | |
{ | |
FT_TRACE0(( "FTC_CMapCache_Lookup: bad arguments, returning 0\n" )); | |
return 0; | |
} | |
if ( !face_id ) | |
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, (FT_UInt)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, &node ); | |
#endif | |
if ( error ) | |
goto Exit; | |
FT_ASSERT( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first ) < | |
FTC_CMAP_INDICES_MAX ); | |
/* something rotten can happen with rogue clients */ | |
if ( (FT_UInt)( char_code - FTC_CMAP_NODE( node )->first >= | |
FTC_CMAP_INDICES_MAX ) ) | |
return 0; /* XXX: should return appropriate error */ | |
gindex = FTC_CMAP_NODE( node )->indices[char_code - | |
FTC_CMAP_NODE( node )->first]; | |
if ( gindex == FTC_CMAP_UNKNOWN ) | |
{ | |
FT_Face face; | |
gindex = 0; | |
error = FTC_Manager_LookupFace( cache->manager, | |
FTC_CMAP_NODE( 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 && !no_cmap_change ) | |
FT_Set_Charmap( face, cmap ); | |
gindex = FT_Get_Char_Index( face, char_code ); | |
if ( old != cmap && !no_cmap_change ) | |
FT_Set_Charmap( face, old ); | |
} | |
FTC_CMAP_NODE( node )->indices[char_code - | |
FTC_CMAP_NODE( node )->first] | |
= (FT_UShort)gindex; | |
} | |
Exit: | |
return gindex; | |
} | |
/* END */ |