lib/3rdparty/freetype/src/base/ftglyph.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ftglyph.c                                                              */
   4 /*                                                                         */
   5 /*    FreeType convenience functions to handle glyphs (body).              */
   6 /*                                                                         */
   7 /*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2007, 2008, 2010 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   /*                                                                       */
  20   /*  This file contains the definition of several convenience functions   */
  21   /*  that can be used by client applications to easily retrieve glyph     */
  22   /*  bitmaps and outlines from a given face.                              */
  23   /*                                                                       */
  24   /*  These functions should be optional if you are writing a font server  */
  25   /*  or text layout engine on top of FreeType.  However, they are pretty  */
  26   /*  handy for many other simple uses of the library.                     */
  27   /*                                                                       */
  28   /*************************************************************************/
  29
  30
  31 #include <ft2build.h>
  32 #include FT_GLYPH_H
  33 #include FT_OUTLINE_H
  34 #include FT_BITMAP_H
  35 #include FT_INTERNAL_OBJECTS_H
  36
  37 #include "basepic.h"
  38
  39   /*************************************************************************/
  40   /*                                                                       */
  41   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  42   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  43   /* messages during execution.                                            */
  44   /*                                                                       */
  45 #undef  FT_COMPONENT
  46 #define FT_COMPONENT  trace_glyph
  47
  48
  49   /*************************************************************************/
  50   /*************************************************************************/
  51   /****                                                                 ****/
  52   /****   FT_BitmapGlyph support                                        ****/
  53   /****                                                                 ****/
  54   /*************************************************************************/
  55   /*************************************************************************/
  56
  57   FT_CALLBACK_DEF( FT_Error )
  58   ft_bitmap_glyph_init( FT_Glyph      bitmap_glyph,
  59                         FT_GlyphSlot  slot )
  60   {
  61     FT_BitmapGlyph  glyph   = (FT_BitmapGlyph)bitmap_glyph;
  62     FT_Error        error   = FT_Err_Ok;
  63     FT_Library      library = FT_GLYPH( glyph )->library;
  64
  65
  66     if ( slot->format != FT_GLYPH_FORMAT_BITMAP )
  67     {
  68       error = FT_Err_Invalid_Glyph_Format;
  69       goto Exit;
  70     }
  71
  72     glyph->left = slot->bitmap_left;
  73     glyph->top  = slot->bitmap_top;
  74
  75     /* do lazy copying whenever possible */
  76     if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
  77     {
  78       glyph->bitmap = slot->bitmap;
  79       slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
  80     }
  81     else
  82     {
  83       FT_Bitmap_New( &glyph->bitmap );
  84       error = FT_Bitmap_Copy( library, &slot->bitmap, &glyph->bitmap );
  85     }
  86
  87   Exit:
  88     return error;
  89   }
  90
  91
  92   FT_CALLBACK_DEF( FT_Error )
  93   ft_bitmap_glyph_copy( FT_Glyph  bitmap_source,
  94                         FT_Glyph  bitmap_target )
  95   {
  96     FT_Library      library = bitmap_source->library;
  97     FT_BitmapGlyph  source  = (FT_BitmapGlyph)bitmap_source;
  98     FT_BitmapGlyph  target  = (FT_BitmapGlyph)bitmap_target;
  99
 100
 101     target->left = source->left;
 102     target->top  = source->top;
 103
 104     return FT_Bitmap_Copy( library, &source->bitmap, &target->bitmap );
 105   }
 106
 107
 108   FT_CALLBACK_DEF( void )
 109   ft_bitmap_glyph_done( FT_Glyph  bitmap_glyph )
 110   {
 111     FT_BitmapGlyph  glyph   = (FT_BitmapGlyph)bitmap_glyph;
 112     FT_Library      library = FT_GLYPH( glyph )->library;
 113
 114
 115     FT_Bitmap_Done( library, &glyph->bitmap );
 116   }
 117
 118
 119   FT_CALLBACK_DEF( void )
 120   ft_bitmap_glyph_bbox( FT_Glyph  bitmap_glyph,
 121                         FT_BBox*  cbox )
 122   {
 123     FT_BitmapGlyph  glyph = (FT_BitmapGlyph)bitmap_glyph;
 124
 125
 126     cbox->xMin = glyph->left << 6;
 127     cbox->xMax = cbox->xMin + ( glyph->bitmap.width << 6 );
 128     cbox->yMax = glyph->top << 6;
 129     cbox->yMin = cbox->yMax - ( glyph->bitmap.rows << 6 );
 130   }
 131
 132
 133   FT_DEFINE_GLYPH(ft_bitmap_glyph_class,
 134     sizeof ( FT_BitmapGlyphRec ),
 135     FT_GLYPH_FORMAT_BITMAP,
 136
 137     ft_bitmap_glyph_init,
 138     ft_bitmap_glyph_done,
 139     ft_bitmap_glyph_copy,
 140     0,                          /* FT_Glyph_TransformFunc */
 141     ft_bitmap_glyph_bbox,
 142     0                           /* FT_Glyph_PrepareFunc   */
 143   )
 144
 145
 146   /*************************************************************************/
 147   /*************************************************************************/
 148   /****                                                                 ****/
 149   /****   FT_OutlineGlyph support                                       ****/
 150   /****                                                                 ****/
 151   /*************************************************************************/
 152   /*************************************************************************/
 153
 154
 155   FT_CALLBACK_DEF( FT_Error )
 156   ft_outline_glyph_init( FT_Glyph      outline_glyph,
 157                          FT_GlyphSlot  slot )
 158   {
 159     FT_OutlineGlyph  glyph   = (FT_OutlineGlyph)outline_glyph;
 160     FT_Error         error   = FT_Err_Ok;
 161     FT_Library       library = FT_GLYPH( glyph )->library;
 162     FT_Outline*      source  = &slot->outline;
 163     FT_Outline*      target  = &glyph->outline;
 164
 165
 166     /* check format in glyph slot */
 167     if ( slot->format != FT_GLYPH_FORMAT_OUTLINE )
 168     {
 169       error = FT_Err_Invalid_Glyph_Format;
 170       goto Exit;
 171     }
 172
 173     /* allocate new outline */
 174     error = FT_Outline_New( library, source->n_points, source->n_contours,
 175                             &glyph->outline );
 176     if ( error )
 177       goto Exit;
 178
 179     FT_Outline_Copy( source, target );
 180
 181   Exit:
 182     return error;
 183   }
 184
 185
 186   FT_CALLBACK_DEF( void )
 187   ft_outline_glyph_done( FT_Glyph  outline_glyph )
 188   {
 189     FT_OutlineGlyph  glyph = (FT_OutlineGlyph)outline_glyph;
 190
 191
 192     FT_Outline_Done( FT_GLYPH( glyph )->library, &glyph->outline );
 193   }
 194
 195
 196   FT_CALLBACK_DEF( FT_Error )
 197   ft_outline_glyph_copy( FT_Glyph  outline_source,
 198                          FT_Glyph  outline_target )
 199   {
 200     FT_OutlineGlyph  source  = (FT_OutlineGlyph)outline_source;
 201     FT_OutlineGlyph  target  = (FT_OutlineGlyph)outline_target;
 202     FT_Error         error;
 203     FT_Library       library = FT_GLYPH( source )->library;
 204
 205
 206     error = FT_Outline_New( library, source->outline.n_points,
 207                             source->outline.n_contours, &target->outline );
 208     if ( !error )
 209       FT_Outline_Copy( &source->outline, &target->outline );
 210
 211     return error;
 212   }
 213
 214
 215   FT_CALLBACK_DEF( void )
 216   ft_outline_glyph_transform( FT_Glyph          outline_glyph,
 217                               const FT_Matrix*  matrix,
 218                               const FT_Vector*  delta )
 219   {
 220     FT_OutlineGlyph  glyph = (FT_OutlineGlyph)outline_glyph;
 221
 222
 223     if ( matrix )
 224       FT_Outline_Transform( &glyph->outline, matrix );
 225
 226     if ( delta )
 227       FT_Outline_Translate( &glyph->outline, delta->x, delta->y );
 228   }
 229
 230
 231   FT_CALLBACK_DEF( void )
 232   ft_outline_glyph_bbox( FT_Glyph  outline_glyph,
 233                          FT_BBox*  bbox )
 234   {
 235     FT_OutlineGlyph  glyph = (FT_OutlineGlyph)outline_glyph;
 236
 237
 238     FT_Outline_Get_CBox( &glyph->outline, bbox );
 239   }
 240
 241
 242   FT_CALLBACK_DEF( FT_Error )
 243   ft_outline_glyph_prepare( FT_Glyph      outline_glyph,
 244                             FT_GlyphSlot  slot )
 245   {
 246     FT_OutlineGlyph  glyph = (FT_OutlineGlyph)outline_glyph;
 247
 248
 249     slot->format         = FT_GLYPH_FORMAT_OUTLINE;
 250     slot->outline        = glyph->outline;
 251     slot->outline.flags &= ~FT_OUTLINE_OWNER;
 252
 253     return FT_Err_Ok;
 254   }
 255
 256
 257   FT_DEFINE_GLYPH( ft_outline_glyph_class,
 258     sizeof ( FT_OutlineGlyphRec ),
 259     FT_GLYPH_FORMAT_OUTLINE,
 260
 261     ft_outline_glyph_init,
 262     ft_outline_glyph_done,
 263     ft_outline_glyph_copy,
 264     ft_outline_glyph_transform,
 265     ft_outline_glyph_bbox,
 266     ft_outline_glyph_prepare
 267   )
 268
 269
 270   /*************************************************************************/
 271   /*************************************************************************/
 272   /****                                                                 ****/
 273   /****   FT_Glyph class and API                                        ****/
 274   /****                                                                 ****/
 275   /*************************************************************************/
 276   /*************************************************************************/
 277
 278    static FT_Error
 279    ft_new_glyph( FT_Library             library,
 280                  const FT_Glyph_Class*  clazz,
 281                  FT_Glyph*              aglyph )
 282    {
 283      FT_Memory  memory = library->memory;
 284      FT_Error   error;
 285      FT_Glyph   glyph  = NULL;
 286
 287
 288      *aglyph = 0;
 289
 290      if ( !FT_ALLOC( glyph, clazz->glyph_size ) )
 291      {
 292        glyph->library = library;
 293        glyph->clazz   = clazz;
 294        glyph->format  = clazz->glyph_format;
 295
 296        *aglyph = glyph;
 297      }
 298
 299      return error;
 300    }
 301
 302
 303   /* documentation is in ftglyph.h */
 304
 305   FT_EXPORT_DEF( FT_Error )
 306   FT_Glyph_Copy( FT_Glyph   source,
 307                  FT_Glyph  *target )
 308   {
 309     FT_Glyph               copy;
 310     FT_Error               error;
 311     const FT_Glyph_Class*  clazz;
 312
 313
 314     /* check arguments */
 315     if ( !target )
 316     {
 317       error = FT_Err_Invalid_Argument;
 318       goto Exit;
 319     }
 320
 321     *target = 0;
 322
 323     if ( !source || !source->clazz )
 324     {
 325       error = FT_Err_Invalid_Argument;
 326       goto Exit;
 327     }
 328
 329     clazz = source->clazz;
 330     error = ft_new_glyph( source->library, clazz, &copy );
 331     if ( error )
 332       goto Exit;
 333
 334     copy->advance = source->advance;
 335     copy->format  = source->format;
 336
 337     if ( clazz->glyph_copy )
 338       error = clazz->glyph_copy( source, copy );
 339
 340     if ( error )
 341       FT_Done_Glyph( copy );
 342     else
 343       *target = copy;
 344
 345   Exit:
 346     return error;
 347   }
 348
 349
 350   /* documentation is in ftglyph.h */
 351
 352   FT_EXPORT_DEF( FT_Error )
 353   FT_Get_Glyph( FT_GlyphSlot  slot,
 354                 FT_Glyph     *aglyph )
 355   {
 356     FT_Library  library;
 357     FT_Error    error;
 358     FT_Glyph    glyph;
 359
 360     const FT_Glyph_Class*  clazz = 0;
 361
 362
 363     if ( !slot )
 364       return FT_Err_Invalid_Slot_Handle;
 365
 366     library = slot->library;
 367
 368     if ( !aglyph )
 369       return FT_Err_Invalid_Argument;
 370
 371     /* if it is a bitmap, that's easy :-) */
 372     if ( slot->format == FT_GLYPH_FORMAT_BITMAP )
 373       clazz = FT_BITMAP_GLYPH_CLASS_GET;
 374
 375     /* if it is an outline */
 376     else if ( slot->format == FT_GLYPH_FORMAT_OUTLINE )
 377       clazz = FT_OUTLINE_GLYPH_CLASS_GET;
 378
 379     else
 380     {
 381       /* try to find a renderer that supports the glyph image format */
 382       FT_Renderer  render = FT_Lookup_Renderer( library, slot->format, 0 );
 383
 384
 385       if ( render )
 386         clazz = &render->glyph_class;
 387     }
 388
 389     if ( !clazz )
 390     {
 391       error = FT_Err_Invalid_Glyph_Format;
 392       goto Exit;
 393     }
 394
 395     /* create FT_Glyph object */
 396     error = ft_new_glyph( library, clazz, &glyph );
 397     if ( error )
 398       goto Exit;
 399
 400     /* copy advance while converting it to 16.16 format */
 401     glyph->advance.x = slot->advance.x << 10;
 402     glyph->advance.y = slot->advance.y << 10;
 403
 404     /* now import the image from the glyph slot */
 405     error = clazz->glyph_init( glyph, slot );
 406
 407     /* if an error occurred, destroy the glyph */
 408     if ( error )
 409       FT_Done_Glyph( glyph );
 410     else
 411       *aglyph = glyph;
 412
 413   Exit:
 414     return error;
 415   }
 416
 417
 418   /* documentation is in ftglyph.h */
 419
 420   FT_EXPORT_DEF( FT_Error )
 421   FT_Glyph_Transform( FT_Glyph    glyph,
 422                       FT_Matrix*  matrix,
 423                       FT_Vector*  delta )
 424   {
 425     const FT_Glyph_Class*  clazz;
 426     FT_Error               error = FT_Err_Ok;
 427
 428
 429     if ( !glyph || !glyph->clazz )
 430       error = FT_Err_Invalid_Argument;
 431     else
 432     {
 433       clazz = glyph->clazz;
 434       if ( clazz->glyph_transform )
 435       {
 436         /* transform glyph image */
 437         clazz->glyph_transform( glyph, matrix, delta );
 438
 439         /* transform advance vector */
 440         if ( matrix )
 441           FT_Vector_Transform( &glyph->advance, matrix );
 442       }
 443       else
 444         error = FT_Err_Invalid_Glyph_Format;
 445     }
 446     return error;
 447   }
 448
 449
 450   /* documentation is in ftglyph.h */
 451
 452   FT_EXPORT_DEF( void )
 453   FT_Glyph_Get_CBox( FT_Glyph  glyph,
 454                      FT_UInt   bbox_mode,
 455                      FT_BBox  *acbox )
 456   {
 457     const FT_Glyph_Class*  clazz;
 458
 459
 460     if ( !acbox )
 461       return;
 462
 463     acbox->xMin = acbox->yMin = acbox->xMax = acbox->yMax = 0;
 464
 465     if ( !glyph || !glyph->clazz )
 466       return;
 467     else
 468     {
 469       clazz = glyph->clazz;
 470       if ( !clazz->glyph_bbox )
 471         return;
 472       else
 473       {
 474         /* retrieve bbox in 26.6 coordinates */
 475         clazz->glyph_bbox( glyph, acbox );
 476
 477         /* perform grid fitting if needed */
 478         if ( bbox_mode == FT_GLYPH_BBOX_GRIDFIT ||
 479              bbox_mode == FT_GLYPH_BBOX_PIXELS  )
 480         {
 481           acbox->xMin = FT_PIX_FLOOR( acbox->xMin );
 482           acbox->yMin = FT_PIX_FLOOR( acbox->yMin );
 483           acbox->xMax = FT_PIX_CEIL( acbox->xMax );
 484           acbox->yMax = FT_PIX_CEIL( acbox->yMax );
 485         }
 486
 487         /* convert to integer pixels if needed */
 488         if ( bbox_mode == FT_GLYPH_BBOX_TRUNCATE ||
 489              bbox_mode == FT_GLYPH_BBOX_PIXELS   )
 490         {
 491           acbox->xMin >>= 6;
 492           acbox->yMin >>= 6;
 493           acbox->xMax >>= 6;
 494           acbox->yMax >>= 6;
 495         }
 496       }
 497     }
 498     return;
 499   }
 500
 501
 502   /* documentation is in ftglyph.h */
 503
 504   FT_EXPORT_DEF( FT_Error )
 505   FT_Glyph_To_Bitmap( FT_Glyph*       the_glyph,
 506                       FT_Render_Mode  render_mode,
 507                       FT_Vector*      origin,
 508                       FT_Bool         destroy )
 509   {
 510     FT_GlyphSlotRec           dummy;
 511     FT_GlyphSlot_InternalRec  dummy_internal;
 512     FT_Error                  error = FT_Err_Ok;
 513     FT_Glyph                  glyph;
 514     FT_BitmapGlyph            bitmap = NULL;
 515
 516     const FT_Glyph_Class*     clazz;
 517
 518 #ifdef FT_CONFIG_OPTION_PIC
 519     FT_Library                library = FT_GLYPH( glyph )->library;
 520 #endif
 521
 522
 523     /* check argument */
 524     if ( !the_glyph )
 525       goto Bad;
 526
 527     /* we render the glyph into a glyph bitmap using a `dummy' glyph slot */
 528     /* then calling FT_Render_Glyph_Internal()                            */
 529
 530     glyph = *the_glyph;
 531     if ( !glyph )
 532       goto Bad;
 533
 534     clazz = glyph->clazz;
 535
 536     /* when called with a bitmap glyph, do nothing and return successfully */
 537     if ( clazz == FT_BITMAP_GLYPH_CLASS_GET )
 538       goto Exit;
 539
 540     if ( !clazz || !clazz->glyph_prepare )
 541       goto Bad;
 542
 543     FT_MEM_ZERO( &dummy, sizeof ( dummy ) );
 544     FT_MEM_ZERO( &dummy_internal, sizeof ( dummy_internal ) );
 545     dummy.internal = &dummy_internal;
 546     dummy.library  = glyph->library;
 547     dummy.format   = clazz->glyph_format;
 548
 549     /* create result bitmap glyph */
 550     error = ft_new_glyph( glyph->library, FT_BITMAP_GLYPH_CLASS_GET,
 551                           (FT_Glyph*)(void*)&bitmap );
 552     if ( error )
 553       goto Exit;
 554
 555 #if 1
 556     /* if `origin' is set, translate the glyph image */
 557     if ( origin )
 558       FT_Glyph_Transform( glyph, 0, origin );
 559 #else
 560     FT_UNUSED( origin );
 561 #endif
 562
 563     /* prepare dummy slot for rendering */
 564     error = clazz->glyph_prepare( glyph, &dummy );
 565     if ( !error )
 566       error = FT_Render_Glyph_Internal( glyph->library, &dummy, render_mode );
 567
 568 #if 1
 569     if ( !destroy && origin )
 570     {
 571       FT_Vector  v;
 572
 573
 574       v.x = -origin->x;
 575       v.y = -origin->y;
 576       FT_Glyph_Transform( glyph, 0, &v );
 577     }
 578 #endif
 579
 580     if ( error )
 581       goto Exit;
 582
 583     /* in case of success, copy the bitmap to the glyph bitmap */
 584     error = ft_bitmap_glyph_init( (FT_Glyph)bitmap, &dummy );
 585     if ( error )
 586       goto Exit;
 587
 588     /* copy advance */
 589     bitmap->root.advance = glyph->advance;
 590
 591     if ( destroy )
 592       FT_Done_Glyph( glyph );
 593
 594     *the_glyph = FT_GLYPH( bitmap );
 595
 596   Exit:
 597     if ( error && bitmap )
 598       FT_Done_Glyph( FT_GLYPH( bitmap ) );
 599
 600     return error;
 601
 602   Bad:
 603     error = FT_Err_Invalid_Argument;
 604     goto Exit;
 605   }
 606
 607
 608   /* documentation is in ftglyph.h */
 609
 610   FT_EXPORT_DEF( void )
 611   FT_Done_Glyph( FT_Glyph  glyph )
 612   {
 613     if ( glyph )
 614     {
 615       FT_Memory              memory = glyph->library->memory;
 616       const FT_Glyph_Class*  clazz  = glyph->clazz;
 617
 618
 619       if ( clazz->glyph_done )
 620         clazz->glyph_done( glyph );
 621
 622       FT_FREE( glyph );
 623     }
 624   }
 625
 626
 627 /* END */