libraries/freetype-2.0.5/cffdrivr.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  cffdrivr.c                                                             */
   4 /*                                                                         */
   5 /*    OpenType font driver implementation (body).                          */
   6 /*                                                                         */
   7 /*  Copyright 1996-2001 by                                                 */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19 #include <ft2build.h>
  20 #include FT_FREETYPE_H
  21 #include FT_INTERNAL_DEBUG_H
  22 #include FT_INTERNAL_STREAM_H
  23 #include FT_INTERNAL_SFNT_H
  24 #include FT_TRUETYPE_IDS_H
  25
  26 #include "cffdrivr.h"
  27 #include "cffgload.h"
  28 #include "cffload.h"
  29
  30 #include "cfferrs.h"
  31
  32
  33   /*************************************************************************/
  34   /*                                                                       */
  35   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  36   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  37   /* messages during execution.                                            */
  38   /*                                                                       */
  39 #undef  FT_COMPONENT
  40 #define FT_COMPONENT  trace_cffdriver
  41
  42
  43   /*************************************************************************/
  44   /*************************************************************************/
  45   /*************************************************************************/
  46   /****                                                                 ****/
  47   /****                                                                 ****/
  48   /****                          F A C E S                              ****/
  49   /****                                                                 ****/
  50   /****                                                                 ****/
  51   /*************************************************************************/
  52   /*************************************************************************/
  53   /*************************************************************************/
  54
  55
  56 #undef  PAIR_TAG
  57 #define PAIR_TAG( left, right )  ( ( (FT_ULong)left << 16 ) | \
  58                                      (FT_ULong)right        )
  59
  60
  61   /*************************************************************************/
  62   /*                                                                       */
  63   /* <Function>                                                            */
  64   /*    Get_Kerning                                                        */
  65   /*                                                                       */
  66   /* <Description>                                                         */
  67   /*    A driver method used to return the kerning vector between two      */
  68   /*    glyphs of the same face.                                           */
  69   /*                                                                       */
  70   /* <Input>                                                               */
  71   /*    face        :: A handle to the source face object.                 */
  72   /*                                                                       */
  73   /*    left_glyph  :: The index of the left glyph in the kern pair.       */
  74   /*                                                                       */
  75   /*    right_glyph :: The index of the right glyph in the kern pair.      */
  76   /*                                                                       */
  77   /* <Output>                                                              */
  78   /*    kerning     :: The kerning vector.  This is in font units for      */
  79   /*                   scalable formats, and in pixels for fixed-sizes     */
  80   /*                   formats.                                            */
  81   /*                                                                       */
  82   /* <Return>                                                              */
  83   /*    FreeType error code.  0 means success.                             */
  84   /*                                                                       */
  85   /* <Note>                                                                */
  86   /*    Only horizontal layouts (left-to-right & right-to-left) are        */
  87   /*    supported by this function.  Other layouts, or more sophisticated  */
  88   /*    kernings, are out of scope of this method (the basic driver        */
  89   /*    interface is meant to be simple).                                  */
  90   /*                                                                       */
  91   /*    They can be implemented by format-specific interfaces.             */
  92   /*                                                                       */
  93   static FT_Error
  94   Get_Kerning( TT_Face     face,
  95                FT_UInt     left_glyph,
  96                FT_UInt     right_glyph,
  97                FT_Vector*  kerning )
  98   {
  99     TT_Kern_0_Pair*  pair;
 100
 101
 102     if ( !face )
 103       return CFF_Err_Invalid_Face_Handle;
 104
 105     kerning->x = 0;
 106     kerning->y = 0;
 107
 108     if ( face->kern_pairs )
 109     {
 110       /* there are some kerning pairs in this font file! */
 111       FT_ULong  search_tag = PAIR_TAG( left_glyph, right_glyph );
 112       FT_Long   left, right;
 113
 114
 115       left  = 0;
 116       right = face->num_kern_pairs - 1;
 117
 118       while ( left <= right )
 119       {
 120         FT_Int    middle = left + ( ( right - left ) >> 1 );
 121         FT_ULong  cur_pair;
 122
 123
 124         pair     = face->kern_pairs + middle;
 125         cur_pair = PAIR_TAG( pair->left, pair->right );
 126
 127         if ( cur_pair == search_tag )
 128           goto Found;
 129
 130         if ( cur_pair < search_tag )
 131           left = middle + 1;
 132         else
 133           right = middle - 1;
 134       }
 135     }
 136
 137   Exit:
 138     return CFF_Err_Ok;
 139
 140   Found:
 141     kerning->x = pair->value;
 142     goto Exit;
 143   }
 144
 145
 146 #undef PAIR_TAG
 147
 148
 149   /*************************************************************************/
 150   /*                                                                       */
 151   /* <Function>                                                            */
 152   /*    Load_Glyph                                                         */
 153   /*                                                                       */
 154   /* <Description>                                                         */
 155   /*    A driver method used to load a glyph within a given glyph slot.    */
 156   /*                                                                       */
 157   /* <Input>                                                               */
 158   /*    slot        :: A handle to the target slot object where the glyph  */
 159   /*                   will be loaded.                                     */
 160   /*                                                                       */
 161   /*    size        :: A handle to the source face size at which the glyph */
 162   /*                   must be scaled, loaded, etc.                        */
 163   /*                                                                       */
 164   /*    glyph_index :: The index of the glyph in the font file.            */
 165   /*                                                                       */
 166   /*    load_flags  :: A flag indicating what to load for this glyph.  The */
 167   /*                   FTLOAD_??? constants can be used to control the     */
 168   /*                   glyph loading process (e.g., whether the outline    */
 169   /*                   should be scaled, whether to load bitmaps or not,   */
 170   /*                   whether to hint the outline, etc).                  */
 171   /*                                                                       */
 172   /* <Return>                                                              */
 173   /*    FreeType error code.  0 means success.                             */
 174   /*                                                                       */
 175   static FT_Error
 176   Load_Glyph( CFF_GlyphSlot  slot,
 177               CFF_Size       size,
 178               FT_UShort      glyph_index,
 179               FT_UInt        load_flags )
 180   {
 181     FT_Error  error;
 182
 183
 184     if ( !slot )
 185       return CFF_Err_Invalid_Slot_Handle;
 186
 187     /* check whether we want a scaled outline or bitmap */
 188     if ( !size )
 189       load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;
 190
 191     if ( load_flags & FT_LOAD_NO_SCALE )
 192       size = NULL;
 193
 194     /* reset the size object if necessary */
 195     if ( size )
 196     {
 197       /* these two object must have the same parent */
 198       if ( size->face != slot->root.face )
 199         return CFF_Err_Invalid_Face_Handle;
 200     }
 201
 202     /* now load the glyph outline if necessary */
 203     error = CFF_Load_Glyph( slot, size, glyph_index, load_flags );
 204
 205     /* force drop-out mode to 2 - irrelevant now */
 206     /* slot->outline.dropout_mode = 2; */
 207
 208     return error;
 209   }
 210
 211
 212   /*************************************************************************/
 213   /*************************************************************************/
 214   /*************************************************************************/
 215   /****                                                                 ****/
 216   /****                                                                 ****/
 217   /****             C H A R A C T E R   M A P P I N G S                 ****/
 218   /****                                                                 ****/
 219   /****                                                                 ****/
 220   /*************************************************************************/
 221   /*************************************************************************/
 222   /*************************************************************************/
 223
 224   static FT_Error
 225   cff_get_glyph_name( CFF_Face    face,
 226                       FT_UInt     glyph_index,
 227                       FT_Pointer  buffer,
 228                       FT_UInt     buffer_max )
 229   {
 230     CFF_Font*           font   = (CFF_Font*)face->extra.data;
 231     FT_Memory           memory = FT_FACE_MEMORY(face);
 232     FT_String*          gname;
 233     FT_UShort           sid;
 234     PSNames_Interface*  psnames;
 235     FT_Error            error;
 236
 237     psnames = (PSNames_Interface*)FT_Get_Module_Interface(
 238                 face->root.driver->root.library, "psnames" );
 239
 240     if ( !psnames )
 241     {
 242       FT_ERROR(( "CFF_Init_Face:" ));
 243       FT_ERROR(( " cannot open CFF & CEF fonts\n" ));
 244       FT_ERROR(( "             " ));
 245       FT_ERROR(( " without the `PSNames' module\n" ));
 246       error = CFF_Err_Unknown_File_Format;
 247       goto Exit;
 248     }
 249
 250     /* first, locate the sid in the charset table */
 251     sid = font->charset.sids[glyph_index];
 252
 253     /* now, lookup the name itself */
 254     gname = CFF_Get_String( &font->string_index, sid, psnames );
 255
 256     if ( buffer_max > 0 )
 257     {
 258       FT_UInt  len = strlen( gname );
 259
 260
 261       if ( len >= buffer_max )
 262         len = buffer_max - 1;
 263
 264       MEM_Copy( buffer, gname, len );
 265       ((FT_Byte*)buffer)[len] = 0;
 266     }
 267
 268     FREE ( gname );
 269     error = CFF_Err_Ok;
 270
 271     Exit:
 272       return error;
 273   }
 274
 275
 276   /*************************************************************************/
 277   /*                                                                       */
 278   /* <Function>                                                            */
 279   /*    cff_get_char_index                                                 */
 280   /*                                                                       */
 281   /* <Description>                                                         */
 282   /*    Uses a charmap to return a given character code's glyph index.     */
 283   /*                                                                       */
 284   /* <Input>                                                               */
 285   /*    charmap  :: A handle to the source charmap object.                 */
 286   /*    charcode :: The character code.                                    */
 287   /*                                                                       */
 288   /* <Return>                                                              */
 289   /*    Glyph index.  0 means `undefined character code'.                  */
 290   /*                                                                       */
 291   static FT_UInt
 292   cff_get_char_index( TT_CharMap  charmap,
 293                       FT_Long     charcode )
 294   {
 295     FT_Error       error;
 296     CFF_Face       face;
 297     TT_CMapTable*  cmap;
 298
 299
 300     cmap = &charmap->cmap;
 301     face = (CFF_Face)charmap->root.face;
 302
 303     /* Load table if needed */
 304     if ( !cmap->loaded )
 305     {
 306       SFNT_Interface*  sfnt = (SFNT_Interface*)face->sfnt;
 307
 308
 309       error = sfnt->load_charmap( face, cmap, face->root.stream );
 310       if ( error )
 311         return 0;
 312
 313       cmap->loaded = TRUE;
 314     }
 315
 316     return ( cmap->get_index ? cmap->get_index( cmap, charcode ) : 0 );
 317   }
 318
 319
 320   /*************************************************************************/
 321   /*                                                                       */
 322   /* <Function>                                                            */
 323   /*    cff_get_name_index                                                 */
 324   /*                                                                       */
 325   /* <Description>                                                         */
 326   /*    Uses the psnames module and the CFF font's charset to to return a  */
 327   /*    a given glyph name's glyph index.                                  */
 328   /*                                                                       */
 329   /* <Input>                                                               */
 330   /*    face       :: A handle to the source face object.                  */
 331   /*                                                                       */
 332   /*    glyph_name :: The glyph name.                                      */
 333   /*                                                                       */
 334   /* <Return>                                                              */
 335   /*    Glyph index.  0 means `undefined character code'.                  */
 336   /*                                                                       */
 337   static FT_UInt
 338   cff_get_name_index( CFF_Face    face,
 339                       FT_String*  glyph_name )
 340   {
 341     CFF_Font*           cff;
 342     CFF_Charset*        charset;
 343     PSNames_Interface*  psnames;
 344     FT_String*          name;
 345     FT_UShort           sid;
 346     FT_UInt             i;
 347
 348
 349     cff     = face->extra.data;
 350     charset = &cff->charset;
 351
 352     psnames = (PSNames_Interface*)FT_Get_Module_Interface(
 353                 face->root.driver->root.library, "psnames" );
 354
 355     for ( i = 0; i < cff->num_glyphs; i++ )
 356     {
 357       sid = charset->sids[i];
 358
 359       if ( sid > 390 )
 360         name = CFF_Get_Name( &cff->string_index, sid - 391 );
 361       else
 362         name = (FT_String *)psnames->adobe_std_strings( sid );
 363
 364       if ( !strcmp( glyph_name, name ) )
 365         return i;
 366     }
 367
 368     return 0;
 369   }
 370
 371
 372   /*************************************************************************/
 373   /*************************************************************************/
 374   /*************************************************************************/
 375   /****                                                                 ****/
 376   /****                                                                 ****/
 377   /****                D R I V E R  I N T E R F A C E                   ****/
 378   /****                                                                 ****/
 379   /****                                                                 ****/
 380   /*************************************************************************/
 381   /*************************************************************************/
 382   /*************************************************************************/
 383
 384   static FT_Module_Interface
 385   cff_get_interface( CFF_Driver   driver,
 386                      const char*  interface )
 387   {
 388     FT_Module  sfnt;
 389
 390 #ifndef FT_CONFIG_OPTION_NO_GLYPH_NAMES
 391
 392     if ( strcmp( (const char*)interface, "glyph_name" ) == 0 )
 393       return (FT_Module_Interface)cff_get_glyph_name;
 394
 395     if ( strcmp( (const char*)interface, "name_index" ) == 0 )
 396       return (FT_Module_Interface)cff_get_name_index;
 397
 398 #endif
 399
 400     /* we simply pass our request to the `sfnt' module */
 401     sfnt = FT_Get_Module( driver->root.root.library, "sfnt" );
 402
 403     return sfnt ? sfnt->clazz->get_interface( sfnt, interface ) : 0;
 404   }
 405
 406
 407   /* The FT_DriverInterface structure is defined in ftdriver.h. */
 408
 409   FT_CALLBACK_TABLE_DEF
 410   const FT_Driver_Class  cff_driver_class =
 411   {
 412     /* begin with the FT_Module_Class fields */
 413     {
 414       ft_module_font_driver | ft_module_driver_scalable,
 415       sizeof( CFF_DriverRec ),
 416       "cff",
 417       0x10000L,
 418       0x20000L,
 419
 420       0,   /* module-specific interface */
 421
 422       (FT_Module_Constructor)CFF_Init_Driver,
 423       (FT_Module_Destructor) CFF_Done_Driver,
 424       (FT_Module_Requester)  cff_get_interface,
 425     },
 426
 427     /* now the specific driver fields */
 428     sizeof( TT_FaceRec ),
 429     sizeof( FT_SizeRec ),
 430     sizeof( CFF_GlyphSlotRec ),
 431
 432     (FTDriver_initFace)     CFF_Init_Face,
 433     (FTDriver_doneFace)     CFF_Done_Face,
 434     (FTDriver_initSize)     0,
 435     (FTDriver_doneSize)     0,
 436     (FTDriver_initGlyphSlot)0,
 437     (FTDriver_doneGlyphSlot)0,
 438
 439     (FTDriver_setCharSizes) 0,
 440     (FTDriver_setPixelSizes)0,
 441
 442     (FTDriver_loadGlyph)    Load_Glyph,
 443     (FTDriver_getCharIndex) cff_get_char_index,
 444
 445     (FTDriver_getKerning)   Get_Kerning,
 446     (FTDriver_attachFile)   0,
 447     (FTDriver_getAdvances)  0
 448   };
 449
 450
 451 #ifdef FT_CONFIG_OPTION_DYNAMIC_DRIVERS
 452
 453
 454   /*************************************************************************/
 455   /*                                                                       */
 456   /* <Function>                                                            */
 457   /*    getDriverClass                                                     */
 458   /*                                                                       */
 459   /* <Description>                                                         */
 460   /*    This function is used when compiling the TrueType driver as a      */
 461   /*    shared library (`.DLL' or `.so').  It will be used by the          */
 462   /*    high-level library of FreeType to retrieve the address of the      */
 463   /*    driver's generic interface.                                        */
 464   /*                                                                       */
 465   /*    It shouldn't be implemented in a static build, as each driver must */
 466   /*    have the same function as an exported entry point.                 */
 467   /*                                                                       */
 468   /* <Return>                                                              */
 469   /*    The address of the TrueType's driver generic interface.  The       */
 470   /*    format-specific interface can then be retrieved through the method */
 471   /*    interface->get_format_interface.                                   */
 472   /*                                                                       */
 473   FT_EXPORT_DEF( const FT_Driver_Class* )
 474   getDriverClass( void )
 475   {
 476     return &cff_driver_class;
 477   }
 478
 479
 480 #endif /* CONFIG_OPTION_DYNAMIC_DRIVERS */
 481
 482
 483 /* END */