subsys/win32k/freetype/src/cff/t2driver.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  t2driver.c                                                             */
   4 /*                                                                         */
   5 /*    OpenType font driver implementation (body).                          */
   6 /*                                                                         */
   7 /*  Copyright 1996-2000 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 <freetype/freetype.h>
  20 #include <freetype/internal/ftdebug.h>
  21 #include <freetype/internal/ftstream.h>
  22 #include <freetype/internal/sfnt.h>
  23 #include <freetype/ttnameid.h>
  24
  25 #include <freetype/internal/t2errors.h>
  26
  27
  28 #ifdef FT_FLAT_COMPILE
  29
  30 #include "t2driver.h"
  31 #include "t2gload.h"
  32
  33 #else
  34
  35 #include <freetype/src/cff/t2driver.h>
  36 #include <freetype/src/cff/t2gload.h>
  37
  38 #endif
  39
  40
  41   /*************************************************************************/
  42   /*                                                                       */
  43   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  44   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  45   /* messages during execution.                                            */
  46   /*                                                                       */
  47 #undef  FT_COMPONENT
  48 #define FT_COMPONENT  trace_t2driver
  49
  50
  51   /*************************************************************************/
  52   /*************************************************************************/
  53   /*************************************************************************/
  54   /****                                                                 ****/
  55   /****                                                                 ****/
  56   /****                          F A C E S                              ****/
  57   /****                                                                 ****/
  58   /****                                                                 ****/
  59   /*************************************************************************/
  60   /*************************************************************************/
  61   /*************************************************************************/
  62
  63
  64 #undef  PAIR_TAG
  65 #define PAIR_TAG( left, right )  ( ( (FT_ULong)left << 16 ) | \
  66                                      (FT_ULong)right        )
  67
  68
  69   /*************************************************************************/
  70   /*                                                                       */
  71   /* <Function>                                                            */
  72   /*    Get_Kerning                                                        */
  73   /*                                                                       */
  74   /* <Description>                                                         */
  75   /*    A driver method used to return the kerning vector between two      */
  76   /*    glyphs of the same face.                                           */
  77   /*                                                                       */
  78   /* <Input>                                                               */
  79   /*    face        :: A handle to the source face object.                 */
  80   /*                                                                       */
  81   /*    left_glyph  :: The index of the left glyph in the kern pair.       */
  82   /*                                                                       */
  83   /*    right_glyph :: The index of the right glyph in the kern pair.      */
  84   /*                                                                       */
  85   /* <Output>                                                              */
  86   /*    kerning     :: The kerning vector.  This is in font units for      */
  87   /*                   scalable formats, and in pixels for fixed-sizes     */
  88   /*                   formats.                                            */
  89   /*                                                                       */
  90   /* <Return>                                                              */
  91   /*    FreeType error code.  0 means success.                             */
  92   /*                                                                       */
  93   /* <Note>                                                                */
  94   /*    Only horizontal layouts (left-to-right & right-to-left) are        */
  95   /*    supported by this function.  Other layouts, or more sophisticated  */
  96   /*    kernings, are out of scope of this method (the basic driver        */
  97   /*    interface is meant to be simple).                                  */
  98   /*                                                                       */
  99   /*    They can be implemented by format-specific interfaces.             */
 100   /*                                                                       */
 101   static
 102   FT_Error  Get_Kerning( TT_Face     face,
 103                          FT_UInt     left_glyph,
 104                          FT_UInt     right_glyph,
 105                          FT_Vector*  kerning )
 106   {
 107     TT_Kern_0_Pair*  pair;
 108
 109
 110     if ( !face )
 111       return T2_Err_Invalid_Face_Handle;
 112
 113     kerning->x = 0;
 114     kerning->y = 0;
 115
 116     if ( face->kern_pairs )
 117     {
 118       /* there are some kerning pairs in this font file! */
 119       FT_ULong  search_tag = PAIR_TAG( left_glyph, right_glyph );
 120       FT_Long   left, right;
 121
 122
 123       left  = 0;
 124       right = face->num_kern_pairs - 1;
 125
 126       while ( left <= right )
 127       {
 128         FT_Int    middle = left + ( ( right - left ) >> 1 );
 129         FT_ULong  cur_pair;
 130
 131
 132         pair     = face->kern_pairs + middle;
 133         cur_pair = PAIR_TAG( pair->left, pair->right );
 134
 135         if ( cur_pair == search_tag )
 136           goto Found;
 137
 138         if ( cur_pair < search_tag )
 139           left = middle + 1;
 140         else
 141           right = middle - 1;
 142       }
 143     }
 144
 145   Exit:
 146     return T2_Err_Ok;
 147
 148   Found:
 149     kerning->x = pair->value;
 150     goto Exit;
 151   }
 152
 153
 154 #undef PAIR_TAG
 155
 156
 157   /*************************************************************************/
 158   /*                                                                       */
 159   /* <Function>                                                            */
 160   /*    Load_Glyph                                                         */
 161   /*                                                                       */
 162   /* <Description>                                                         */
 163   /*    A driver method used to load a glyph within a given glyph slot.    */
 164   /*                                                                       */
 165   /* <Input>                                                               */
 166   /*    slot        :: A handle to the target slot object where the glyph  */
 167   /*                   will be loaded.                                     */
 168   /*                                                                       */
 169   /*    size        :: A handle to the source face size at which the glyph */
 170   /*                   must be scaled, loaded, etc.                        */
 171   /*                                                                       */
 172   /*    glyph_index :: The index of the glyph in the font file.            */
 173   /*                                                                       */
 174   /*    load_flags  :: A flag indicating what to load for this glyph.  The */
 175   /*                   FTLOAD_??? constants can be used to control the     */
 176   /*                   glyph loading process (e.g., whether the outline    */
 177   /*                   should be scaled, whether to load bitmaps or not,   */
 178   /*                   whether to hint the outline, etc).                  */
 179   /*                                                                       */
 180   /* <Return>                                                              */
 181   /*    FreeType error code.  0 means success.                             */
 182   /*                                                                       */
 183   static
 184   FT_Error  Load_Glyph( T2_GlyphSlot  slot,
 185                         T2_Size       size,
 186                         FT_UShort     glyph_index,
 187                         FT_UInt       load_flags )
 188   {
 189     FT_Error  error;
 190
 191
 192     if ( !slot )
 193       return T2_Err_Invalid_Glyph_Handle;
 194
 195     /* check whether we want a scaled outline or bitmap */
 196     if ( !size )
 197       load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;
 198
 199     if ( load_flags & FT_LOAD_NO_SCALE )
 200       size = NULL;
 201
 202     /* reset the size object if necessary */
 203     if ( size )
 204     {
 205       /* these two object must have the same parent */
 206       if ( size->face != slot->root.face )
 207         return T2_Err_Invalid_Face_Handle;
 208     }
 209
 210     /* now load the glyph outline if necessary */
 211     error = T2_Load_Glyph( slot, size, glyph_index, load_flags );
 212
 213     /* force drop-out mode to 2 - irrelevant now */
 214     /* slot->outline.dropout_mode = 2; */
 215
 216     return error;
 217   }
 218
 219
 220   /*************************************************************************/
 221   /*************************************************************************/
 222   /*************************************************************************/
 223   /****                                                                 ****/
 224   /****                                                                 ****/
 225   /****             C H A R A C T E R   M A P P I N G S                 ****/
 226   /****                                                                 ****/
 227   /****                                                                 ****/
 228   /*************************************************************************/
 229   /*************************************************************************/
 230   /*************************************************************************/
 231
 232   /*************************************************************************/
 233   /*                                                                       */
 234   /* <Function>                                                            */
 235   /*    Get_Char_Index                                                     */
 236   /*                                                                       */
 237   /* <Description>                                                         */
 238   /*    Uses a charmap to return a given character code's glyph index.     */
 239   /*                                                                       */
 240   /* <Input>                                                               */
 241   /*    charmap  :: A handle to the source charmap object.                 */
 242   /*    charcode :: The character code.                                    */
 243   /*                                                                       */
 244   /* <Return>                                                              */
 245   /*    Glyph index.  0 means `undefined character code'.                  */
 246   /*                                                                       */
 247   static
 248   FT_UInt  t2_get_char_index( TT_CharMap  charmap,
 249                               FT_Long     charcode )
 250   {
 251     FT_Error       error;
 252     T2_Face        face;
 253     TT_CMapTable*  cmap;
 254
 255
 256     cmap = &charmap->cmap;
 257     face = (T2_Face)charmap->root.face;
 258
 259     /* Load table if needed */
 260     if ( !cmap->loaded )
 261     {
 262       SFNT_Interface*  sfnt = (SFNT_Interface*)face->sfnt;
 263
 264
 265       error = sfnt->load_charmap( face, cmap, face->root.stream );
 266       if ( error )
 267         return 0;
 268
 269       cmap->loaded = TRUE;
 270     }
 271
 272     return ( cmap->get_index ? cmap->get_index( cmap, charcode ) : 0 );
 273   }
 274
 275
 276   /*************************************************************************/
 277   /*************************************************************************/
 278   /*************************************************************************/
 279   /****                                                                 ****/
 280   /****                                                                 ****/
 281   /****                D R I V E R  I N T E R F A C E                   ****/
 282   /****                                                                 ****/
 283   /****                                                                 ****/
 284   /*************************************************************************/
 285   /*************************************************************************/
 286   /*************************************************************************/
 287
 288
 289   static
 290   FT_Module_Interface  t2_get_interface( T2_Driver    driver,
 291                                          const char*  interface )
 292   {
 293     FT_Module  sfnt;
 294
 295
 296     /* we simply pass our request to the `sfnt' module */
 297     sfnt = FT_Get_Module( driver->root.root.library, "sfnt" );
 298
 299     return sfnt ? sfnt->clazz->get_interface( sfnt, interface ) : 0;
 300   }
 301
 302
 303   /* The FT_DriverInterface structure is defined in ftdriver.h. */
 304
 305   const FT_Driver_Class   cff_driver_class =
 306   {
 307     /* begin with the FT_Module_Class fields */
 308     {
 309       ft_module_font_driver | ft_module_driver_scalable,
 310       sizeof( T2_DriverRec ),
 311       "cff",
 312       0x10000L,
 313       0x20000L,
 314
 315       0,   /* module-specific interface */
 316
 317       (FT_Module_Constructor)T2_Init_Driver,
 318       (FT_Module_Destructor) T2_Done_Driver,
 319       (FT_Module_Requester)  t2_get_interface,
 320     },
 321
 322     /* now the specific driver fields */
 323     sizeof( TT_FaceRec ),
 324     sizeof( FT_SizeRec ),
 325     sizeof( T2_GlyphSlotRec ),
 326
 327     (FTDriver_initFace)     T2_Init_Face,
 328     (FTDriver_doneFace)     T2_Done_Face,
 329     (FTDriver_initSize)     0,
 330     (FTDriver_doneSize)     0,
 331     (FTDriver_initGlyphSlot)0,
 332     (FTDriver_doneGlyphSlot)0,
 333
 334     (FTDriver_setCharSizes) 0,
 335     (FTDriver_setPixelSizes)0,
 336
 337     (FTDriver_loadGlyph)    Load_Glyph,
 338     (FTDriver_getCharIndex) t2_get_char_index,
 339
 340     (FTDriver_getKerning)   Get_Kerning,
 341     (FTDriver_attachFile)   0,
 342     (FTDriver_getAdvances)  0
 343   };
 344
 345
 346 #ifdef FT_CONFIG_OPTION_DYNAMIC_DRIVERS
 347
 348
 349   /*************************************************************************/
 350   /*                                                                       */
 351   /* <Function>                                                            */
 352   /*    getDriverClass                                                     */
 353   /*                                                                       */
 354   /* <Description>                                                         */
 355   /*    This function is used when compiling the TrueType driver as a      */
 356   /*    shared library (`.DLL' or `.so').  It will be used by the          */
 357   /*    high-level library of FreeType to retrieve the address of the      */
 358   /*    driver's generic interface.                                        */
 359   /*                                                                       */
 360   /*    It shouldn't be implemented in a static build, as each driver must */
 361   /*    have the same function as an exported entry point.                 */
 362   /*                                                                       */
 363   /* <Return>                                                              */
 364   /*    The address of the TrueType's driver generic interface.  The       */
 365   /*    format-specific interface can then be retrieved through the method */
 366   /*    interface->get_format_interface.                                   */
 367   /*                                                                       */
 368   EXPORT_FUNC( FT_Driver_Class* )  getDriverClass( void )
 369   {
 370     return &cff_driver_class;
 371   }
 372
 373
 374 #endif /* CONFIG_OPTION_DYNAMIC_DRIVERS */
 375
 376
 377 /* END */