ttgload.c revision a7d8bdbcfeb65b4859fe553df9d4922627837888
1/***************************************************************************/
2/*                                                                         */
3/*  ttgload.c                                                              */
4/*                                                                         */
5/*    TrueType Glyph Loader (body).                                        */
6/*                                                                         */
7/*  Copyright 1996-2016 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_INTERNAL_DEBUG_H
21#include FT_INTERNAL_CALC_H
22#include FT_INTERNAL_STREAM_H
23#include FT_INTERNAL_SFNT_H
24#include FT_TRUETYPE_TAGS_H
25#include FT_OUTLINE_H
26#include FT_TRUETYPE_DRIVER_H
27#include FT_LIST_H
28
29#include "ttgload.h"
30#include "ttpload.h"
31
32#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
33#include "ttgxvar.h"
34#endif
35
36#include "tterrors.h"
37#include "ttsubpix.h"
38
39
40  /*************************************************************************/
41  /*                                                                       */
42  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
43  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
44  /* messages during execution.                                            */
45  /*                                                                       */
46#undef  FT_COMPONENT
47#define FT_COMPONENT  trace_ttgload
48
49
50  /*************************************************************************/
51  /*                                                                       */
52  /* Composite glyph flags.                                                */
53  /*                                                                       */
54#define ARGS_ARE_WORDS             0x0001
55#define ARGS_ARE_XY_VALUES         0x0002
56#define ROUND_XY_TO_GRID           0x0004
57#define WE_HAVE_A_SCALE            0x0008
58/* reserved                        0x0010 */
59#define MORE_COMPONENTS            0x0020
60#define WE_HAVE_AN_XY_SCALE        0x0040
61#define WE_HAVE_A_2X2              0x0080
62#define WE_HAVE_INSTR              0x0100
63#define USE_MY_METRICS             0x0200
64#define OVERLAP_COMPOUND           0x0400
65#define SCALED_COMPONENT_OFFSET    0x0800
66#define UNSCALED_COMPONENT_OFFSET  0x1000
67
68
69  /*************************************************************************/
70  /*                                                                       */
71  /* Return the horizontal metrics in font units for a given glyph.        */
72  /*                                                                       */
73  FT_LOCAL_DEF( void )
74  TT_Get_HMetrics( TT_Face     face,
75                   FT_UInt     idx,
76                   FT_Short*   lsb,
77                   FT_UShort*  aw )
78  {
79    ( (SFNT_Service)face->sfnt )->get_metrics( face, 0, idx, lsb, aw );
80
81    FT_TRACE5(( "  advance width (font units): %d\n", *aw ));
82    FT_TRACE5(( "  left side bearing (font units): %d\n", *lsb ));
83  }
84
85
86  /*************************************************************************/
87  /*                                                                       */
88  /* Return the vertical metrics in font units for a given glyph.          */
89  /* See macro `TT_LOADER_SET_PP' below for explanations.                  */
90  /*                                                                       */
91  FT_LOCAL_DEF( void )
92  TT_Get_VMetrics( TT_Face     face,
93                   FT_UInt     idx,
94                   FT_Pos      yMax,
95                   FT_Short*   tsb,
96                   FT_UShort*  ah )
97  {
98    if ( face->vertical_info )
99      ( (SFNT_Service)face->sfnt )->get_metrics( face, 1, idx, tsb, ah );
100
101    else if ( face->os2.version != 0xFFFFU )
102    {
103      *tsb = (FT_Short)( face->os2.sTypoAscender - yMax );
104      *ah  = (FT_UShort)FT_ABS( face->os2.sTypoAscender -
105                                face->os2.sTypoDescender );
106    }
107
108    else
109    {
110      *tsb = (FT_Short)( face->horizontal.Ascender - yMax );
111      *ah  = (FT_UShort)FT_ABS( face->horizontal.Ascender -
112                                face->horizontal.Descender );
113    }
114
115    FT_TRACE5(( "  advance height (font units): %d\n", *ah ));
116    FT_TRACE5(( "  top side bearing (font units): %d\n", *tsb ));
117  }
118
119
120  static FT_Error
121  tt_get_metrics( TT_Loader  loader,
122                  FT_UInt    glyph_index )
123  {
124    TT_Face    face   = loader->face;
125#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
126    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
127#endif
128
129    FT_Error   error;
130    FT_Stream  stream = loader->stream;
131
132    FT_Short   left_bearing = 0, top_bearing = 0;
133    FT_UShort  advance_width = 0, advance_height = 0;
134
135    /* we must preserve the stream position          */
136    /* (which gets altered by the metrics functions) */
137    FT_ULong  pos = FT_STREAM_POS();
138
139
140    TT_Get_HMetrics( face, glyph_index,
141                     &left_bearing,
142                     &advance_width );
143    TT_Get_VMetrics( face, glyph_index,
144                     loader->bbox.yMax,
145                     &top_bearing,
146                     &advance_height );
147
148    if ( FT_STREAM_SEEK( pos ) )
149      return error;
150
151    loader->left_bearing = left_bearing;
152    loader->advance      = advance_width;
153    loader->top_bearing  = top_bearing;
154    loader->vadvance     = advance_height;
155
156#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
157    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 &&
158         loader->exec                                             )
159    {
160      loader->exec->sph_tweak_flags = 0;
161
162      /* This may not be the right place for this, but it works...  */
163      /* Note that we have to unconditionally load the tweaks since */
164      /* it is possible that glyphs individually switch ClearType's */
165      /* backwards compatibility mode on and off.                   */
166      sph_set_tweaks( loader, glyph_index );
167    }
168#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
169
170    if ( !loader->linear_def )
171    {
172      loader->linear_def = 1;
173      loader->linear     = advance_width;
174    }
175
176    return FT_Err_Ok;
177  }
178
179
180#ifdef FT_CONFIG_OPTION_INCREMENTAL
181
182  static void
183  tt_get_metrics_incr_overrides( TT_Loader  loader,
184                                 FT_UInt    glyph_index )
185  {
186    TT_Face  face = loader->face;
187
188    FT_Short   left_bearing = 0, top_bearing = 0;
189    FT_UShort  advance_width = 0, advance_height = 0;
190
191
192    /* If this is an incrementally loaded font check whether there are */
193    /* overriding metrics for this glyph.                              */
194    if ( face->root.internal->incremental_interface                           &&
195         face->root.internal->incremental_interface->funcs->get_glyph_metrics )
196    {
197      FT_Incremental_MetricsRec  metrics;
198      FT_Error                   error;
199
200
201      metrics.bearing_x = loader->left_bearing;
202      metrics.bearing_y = 0;
203      metrics.advance   = loader->advance;
204      metrics.advance_v = 0;
205
206      error = face->root.internal->incremental_interface->funcs->get_glyph_metrics(
207                face->root.internal->incremental_interface->object,
208                glyph_index, FALSE, &metrics );
209      if ( error )
210        goto Exit;
211
212      left_bearing  = (FT_Short)metrics.bearing_x;
213      advance_width = (FT_UShort)metrics.advance;
214
215#if 0
216
217      /* GWW: Do I do the same for vertical metrics? */
218      metrics.bearing_x = 0;
219      metrics.bearing_y = loader->top_bearing;
220      metrics.advance   = loader->vadvance;
221
222      error = face->root.internal->incremental_interface->funcs->get_glyph_metrics(
223                face->root.internal->incremental_interface->object,
224                glyph_index, TRUE, &metrics );
225      if ( error )
226        goto Exit;
227
228      top_bearing    = (FT_Short)metrics.bearing_y;
229      advance_height = (FT_UShort)metrics.advance;
230
231#endif /* 0 */
232
233      loader->left_bearing = left_bearing;
234      loader->advance      = advance_width;
235      loader->top_bearing  = top_bearing;
236      loader->vadvance     = advance_height;
237
238      if ( !loader->linear_def )
239      {
240        loader->linear_def = 1;
241        loader->linear     = advance_width;
242      }
243    }
244
245  Exit:
246    return;
247  }
248
249#endif /* FT_CONFIG_OPTION_INCREMENTAL */
250
251
252  /*************************************************************************/
253  /*                                                                       */
254  /* The following functions are used by default with TrueType fonts.      */
255  /* However, they can be replaced by alternatives if we need to support   */
256  /* TrueType-compressed formats (like MicroType) in the future.           */
257  /*                                                                       */
258  /*************************************************************************/
259
260  FT_CALLBACK_DEF( FT_Error )
261  TT_Access_Glyph_Frame( TT_Loader  loader,
262                         FT_UInt    glyph_index,
263                         FT_ULong   offset,
264                         FT_UInt    byte_count )
265  {
266    FT_Error   error;
267    FT_Stream  stream = loader->stream;
268
269    /* for non-debug mode */
270    FT_UNUSED( glyph_index );
271
272
273    FT_TRACE4(( "Glyph %ld\n", glyph_index ));
274
275    /* the following line sets the `error' variable through macros! */
276    if ( FT_STREAM_SEEK( offset ) || FT_FRAME_ENTER( byte_count ) )
277      return error;
278
279    loader->cursor = stream->cursor;
280    loader->limit  = stream->limit;
281
282    return FT_Err_Ok;
283  }
284
285
286  FT_CALLBACK_DEF( void )
287  TT_Forget_Glyph_Frame( TT_Loader  loader )
288  {
289    FT_Stream  stream = loader->stream;
290
291
292    FT_FRAME_EXIT();
293  }
294
295
296  FT_CALLBACK_DEF( FT_Error )
297  TT_Load_Glyph_Header( TT_Loader  loader )
298  {
299    FT_Byte*  p     = loader->cursor;
300    FT_Byte*  limit = loader->limit;
301
302
303    if ( p + 10 > limit )
304      return FT_THROW( Invalid_Outline );
305
306    loader->n_contours = FT_NEXT_SHORT( p );
307
308    loader->bbox.xMin = FT_NEXT_SHORT( p );
309    loader->bbox.yMin = FT_NEXT_SHORT( p );
310    loader->bbox.xMax = FT_NEXT_SHORT( p );
311    loader->bbox.yMax = FT_NEXT_SHORT( p );
312
313    FT_TRACE5(( "  # of contours: %d\n", loader->n_contours ));
314    FT_TRACE5(( "  xMin: %4d  xMax: %4d\n", loader->bbox.xMin,
315                                            loader->bbox.xMax ));
316    FT_TRACE5(( "  yMin: %4d  yMax: %4d\n", loader->bbox.yMin,
317                                            loader->bbox.yMax ));
318    loader->cursor = p;
319
320    return FT_Err_Ok;
321  }
322
323
324  FT_CALLBACK_DEF( FT_Error )
325  TT_Load_Simple_Glyph( TT_Loader  load )
326  {
327    FT_Error        error;
328    FT_Byte*        p          = load->cursor;
329    FT_Byte*        limit      = load->limit;
330    FT_GlyphLoader  gloader    = load->gloader;
331    FT_Int          n_contours = load->n_contours;
332    FT_Outline*     outline;
333    FT_UShort       n_ins;
334    FT_Int          n_points;
335    FT_ULong        tmp;
336
337    FT_Byte         *flag, *flag_limit;
338    FT_Byte         c, count;
339    FT_Vector       *vec, *vec_limit;
340    FT_Pos          x;
341    FT_Short        *cont, *cont_limit, prev_cont;
342    FT_Int          xy_size = 0;
343
344
345    /* check that we can add the contours to the glyph */
346    error = FT_GLYPHLOADER_CHECK_POINTS( gloader, 0, n_contours );
347    if ( error )
348      goto Fail;
349
350    /* reading the contours' endpoints & number of points */
351    cont       = gloader->current.outline.contours;
352    cont_limit = cont + n_contours;
353
354    /* check space for contours array + instructions count */
355    if ( n_contours >= 0xFFF || p + ( n_contours + 1 ) * 2 > limit )
356      goto Invalid_Outline;
357
358    prev_cont = FT_NEXT_SHORT( p );
359
360    if ( n_contours > 0 )
361      cont[0] = prev_cont;
362
363    if ( prev_cont < 0 )
364      goto Invalid_Outline;
365
366    for ( cont++; cont < cont_limit; cont++ )
367    {
368      cont[0] = FT_NEXT_SHORT( p );
369      if ( cont[0] <= prev_cont )
370      {
371        /* unordered contours: this is invalid */
372        goto Invalid_Outline;
373      }
374      prev_cont = cont[0];
375    }
376
377    n_points = 0;
378    if ( n_contours > 0 )
379    {
380      n_points = cont[-1] + 1;
381      if ( n_points < 0 )
382        goto Invalid_Outline;
383    }
384
385    /* note that we will add four phantom points later */
386    error = FT_GLYPHLOADER_CHECK_POINTS( gloader, n_points + 4, 0 );
387    if ( error )
388      goto Fail;
389
390    /* reading the bytecode instructions */
391    load->glyph->control_len  = 0;
392    load->glyph->control_data = NULL;
393
394    if ( p + 2 > limit )
395      goto Invalid_Outline;
396
397    n_ins = FT_NEXT_USHORT( p );
398
399    FT_TRACE5(( "  Instructions size: %u\n", n_ins ));
400
401    /* check it */
402    if ( ( limit - p ) < n_ins )
403    {
404      FT_TRACE0(( "TT_Load_Simple_Glyph: instruction count mismatch\n" ));
405      error = FT_THROW( Too_Many_Hints );
406      goto Fail;
407    }
408
409#ifdef TT_USE_BYTECODE_INTERPRETER
410
411    if ( IS_HINTED( load->load_flags ) )
412    {
413      /* we don't trust `maxSizeOfInstructions' in the `maxp' table */
414      /* and thus update the bytecode array size by ourselves       */
415
416      tmp   = load->exec->glyphSize;
417      error = Update_Max( load->exec->memory,
418                          &tmp,
419                          sizeof ( FT_Byte ),
420                          (void*)&load->exec->glyphIns,
421                          n_ins );
422
423      load->exec->glyphSize = (FT_UShort)tmp;
424      if ( error )
425        return error;
426
427      load->glyph->control_len  = n_ins;
428      load->glyph->control_data = load->exec->glyphIns;
429
430      if ( n_ins )
431        FT_MEM_COPY( load->exec->glyphIns, p, (FT_Long)n_ins );
432    }
433
434#endif /* TT_USE_BYTECODE_INTERPRETER */
435
436    p += n_ins;
437
438    outline = &gloader->current.outline;
439
440    /* reading the point tags */
441    flag       = (FT_Byte*)outline->tags;
442    flag_limit = flag + n_points;
443
444    FT_ASSERT( flag != NULL );
445
446    while ( flag < flag_limit )
447    {
448      if ( p + 1 > limit )
449        goto Invalid_Outline;
450
451      *flag++ = c = FT_NEXT_BYTE( p );
452      if ( c & 8 )
453      {
454        if ( p + 1 > limit )
455          goto Invalid_Outline;
456
457        count = FT_NEXT_BYTE( p );
458        if ( flag + (FT_Int)count > flag_limit )
459          goto Invalid_Outline;
460
461        for ( ; count > 0; count-- )
462          *flag++ = c;
463      }
464    }
465
466    /* reading the X coordinates */
467
468    vec       = outline->points;
469    vec_limit = vec + n_points;
470    flag      = (FT_Byte*)outline->tags;
471    x         = 0;
472
473    if ( p + xy_size > limit )
474      goto Invalid_Outline;
475
476    for ( ; vec < vec_limit; vec++, flag++ )
477    {
478      FT_Pos   y = 0;
479      FT_Byte  f = *flag;
480
481
482      if ( f & 2 )
483      {
484        if ( p + 1 > limit )
485          goto Invalid_Outline;
486
487        y = (FT_Pos)FT_NEXT_BYTE( p );
488        if ( ( f & 16 ) == 0 )
489          y = -y;
490      }
491      else if ( ( f & 16 ) == 0 )
492      {
493        if ( p + 2 > limit )
494          goto Invalid_Outline;
495
496        y = (FT_Pos)FT_NEXT_SHORT( p );
497      }
498
499      x     += y;
500      vec->x = x;
501      /* the cast is for stupid compilers */
502      *flag  = (FT_Byte)( f & ~( 2 | 16 ) );
503    }
504
505    /* reading the Y coordinates */
506
507    vec       = gloader->current.outline.points;
508    vec_limit = vec + n_points;
509    flag      = (FT_Byte*)outline->tags;
510    x         = 0;
511
512    for ( ; vec < vec_limit; vec++, flag++ )
513    {
514      FT_Pos   y = 0;
515      FT_Byte  f = *flag;
516
517
518      if ( f & 4 )
519      {
520        if ( p + 1 > limit )
521          goto Invalid_Outline;
522
523        y = (FT_Pos)FT_NEXT_BYTE( p );
524        if ( ( f & 32 ) == 0 )
525          y = -y;
526      }
527      else if ( ( f & 32 ) == 0 )
528      {
529        if ( p + 2 > limit )
530          goto Invalid_Outline;
531
532        y = (FT_Pos)FT_NEXT_SHORT( p );
533      }
534
535      x     += y;
536      vec->y = x;
537      /* the cast is for stupid compilers */
538      *flag  = (FT_Byte)( f & FT_CURVE_TAG_ON );
539    }
540
541    outline->n_points   = (FT_Short)n_points;
542    outline->n_contours = (FT_Short)n_contours;
543
544    load->cursor = p;
545
546  Fail:
547    return error;
548
549  Invalid_Outline:
550    error = FT_THROW( Invalid_Outline );
551    goto Fail;
552  }
553
554
555  FT_CALLBACK_DEF( FT_Error )
556  TT_Load_Composite_Glyph( TT_Loader  loader )
557  {
558    FT_Error        error;
559    FT_Byte*        p       = loader->cursor;
560    FT_Byte*        limit   = loader->limit;
561    FT_GlyphLoader  gloader = loader->gloader;
562    FT_SubGlyph     subglyph;
563    FT_UInt         num_subglyphs;
564
565
566    num_subglyphs = 0;
567
568    do
569    {
570      FT_Fixed  xx, xy, yy, yx;
571      FT_UInt   count;
572
573
574      /* check that we can load a new subglyph */
575      error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs + 1 );
576      if ( error )
577        goto Fail;
578
579      /* check space */
580      if ( p + 4 > limit )
581        goto Invalid_Composite;
582
583      subglyph = gloader->current.subglyphs + num_subglyphs;
584
585      subglyph->arg1 = subglyph->arg2 = 0;
586
587      subglyph->flags = FT_NEXT_USHORT( p );
588      subglyph->index = FT_NEXT_USHORT( p );
589
590      /* check space */
591      count = 2;
592      if ( subglyph->flags & ARGS_ARE_WORDS )
593        count += 2;
594      if ( subglyph->flags & WE_HAVE_A_SCALE )
595        count += 2;
596      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
597        count += 4;
598      else if ( subglyph->flags & WE_HAVE_A_2X2 )
599        count += 8;
600
601      if ( p + count > limit )
602        goto Invalid_Composite;
603
604      /* read arguments */
605      if ( subglyph->flags & ARGS_ARE_XY_VALUES )
606      {
607        if ( subglyph->flags & ARGS_ARE_WORDS )
608        {
609          subglyph->arg1 = FT_NEXT_SHORT( p );
610          subglyph->arg2 = FT_NEXT_SHORT( p );
611        }
612        else
613        {
614          subglyph->arg1 = FT_NEXT_CHAR( p );
615          subglyph->arg2 = FT_NEXT_CHAR( p );
616        }
617      }
618      else
619      {
620        if ( subglyph->flags & ARGS_ARE_WORDS )
621        {
622          subglyph->arg1 = (FT_Int)FT_NEXT_USHORT( p );
623          subglyph->arg2 = (FT_Int)FT_NEXT_USHORT( p );
624        }
625        else
626        {
627          subglyph->arg1 = (FT_Int)FT_NEXT_BYTE( p );
628          subglyph->arg2 = (FT_Int)FT_NEXT_BYTE( p );
629        }
630      }
631
632      /* read transform */
633      xx = yy = 0x10000L;
634      xy = yx = 0;
635
636      if ( subglyph->flags & WE_HAVE_A_SCALE )
637      {
638        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
639        yy = xx;
640      }
641      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
642      {
643        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
644        yy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
645      }
646      else if ( subglyph->flags & WE_HAVE_A_2X2 )
647      {
648        xx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
649        yx = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
650        xy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
651        yy = (FT_Fixed)FT_NEXT_SHORT( p ) * 4;
652      }
653
654      subglyph->transform.xx = xx;
655      subglyph->transform.xy = xy;
656      subglyph->transform.yx = yx;
657      subglyph->transform.yy = yy;
658
659      num_subglyphs++;
660
661    } while ( subglyph->flags & MORE_COMPONENTS );
662
663    gloader->current.num_subglyphs = num_subglyphs;
664    FT_TRACE5(( "  %d components\n", num_subglyphs ));
665
666#ifdef TT_USE_BYTECODE_INTERPRETER
667
668    {
669      FT_Stream  stream = loader->stream;
670
671
672      /* we must undo the FT_FRAME_ENTER in order to point */
673      /* to the composite instructions, if we find some.   */
674      /* We will process them later.                       */
675      /*                                                   */
676      loader->ins_pos = (FT_ULong)( FT_STREAM_POS() +
677                                    p - limit );
678    }
679
680#endif
681
682    loader->cursor = p;
683
684  Fail:
685    return error;
686
687  Invalid_Composite:
688    error = FT_THROW( Invalid_Composite );
689    goto Fail;
690  }
691
692
693  FT_LOCAL_DEF( void )
694  TT_Init_Glyph_Loading( TT_Face  face )
695  {
696    face->access_glyph_frame   = TT_Access_Glyph_Frame;
697    face->read_glyph_header    = TT_Load_Glyph_Header;
698    face->read_simple_glyph    = TT_Load_Simple_Glyph;
699    face->read_composite_glyph = TT_Load_Composite_Glyph;
700    face->forget_glyph_frame   = TT_Forget_Glyph_Frame;
701  }
702
703
704  static void
705  tt_prepare_zone( TT_GlyphZone  zone,
706                   FT_GlyphLoad  load,
707                   FT_UInt       start_point,
708                   FT_UInt       start_contour )
709  {
710    zone->n_points    = (FT_UShort)load->outline.n_points -
711                          (FT_UShort)start_point;
712    zone->n_contours  = load->outline.n_contours -
713                          (FT_Short)start_contour;
714    zone->org         = load->extra_points + start_point;
715    zone->cur         = load->outline.points + start_point;
716    zone->orus        = load->extra_points2 + start_point;
717    zone->tags        = (FT_Byte*)load->outline.tags + start_point;
718    zone->contours    = (FT_UShort*)load->outline.contours + start_contour;
719    zone->first_point = (FT_UShort)start_point;
720  }
721
722
723  /*************************************************************************/
724  /*                                                                       */
725  /* <Function>                                                            */
726  /*    TT_Hint_Glyph                                                      */
727  /*                                                                       */
728  /* <Description>                                                         */
729  /*    Hint the glyph using the zone prepared by the caller.  Note that   */
730  /*    the zone is supposed to include four phantom points.               */
731  /*                                                                       */
732  static FT_Error
733  TT_Hint_Glyph( TT_Loader  loader,
734                 FT_Bool    is_composite )
735  {
736#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
737    TT_Face    face   = loader->face;
738    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
739#endif
740
741    TT_GlyphZone  zone = &loader->zone;
742
743#ifdef TT_USE_BYTECODE_INTERPRETER
744    FT_Long       n_ins;
745#else
746    FT_UNUSED( is_composite );
747#endif
748
749
750#ifdef TT_USE_BYTECODE_INTERPRETER
751    if ( loader->glyph->control_len > 0xFFFFL )
752    {
753      FT_TRACE1(( "TT_Hint_Glyph: too long instructions" ));
754      FT_TRACE1(( " (0x%lx byte) is truncated\n",
755                 loader->glyph->control_len ));
756    }
757    n_ins = loader->glyph->control_len;
758
759    /* save original point position in org */
760    if ( n_ins > 0 )
761      FT_ARRAY_COPY( zone->org, zone->cur, zone->n_points );
762
763    /* Reset graphics state. */
764    loader->exec->GS = loader->size->GS;
765
766    /* XXX: UNDOCUMENTED! Hinting instructions of a composite glyph */
767    /*      completely refer to the (already) hinted subglyphs.     */
768    if ( is_composite )
769    {
770      loader->exec->metrics.x_scale = 1 << 16;
771      loader->exec->metrics.y_scale = 1 << 16;
772
773      FT_ARRAY_COPY( zone->orus, zone->cur, zone->n_points );
774    }
775    else
776    {
777      loader->exec->metrics.x_scale = loader->size->metrics.x_scale;
778      loader->exec->metrics.y_scale = loader->size->metrics.y_scale;
779    }
780#endif
781
782    /* round phantom points */
783    zone->cur[zone->n_points - 4].x =
784      FT_PIX_ROUND( zone->cur[zone->n_points - 4].x );
785    zone->cur[zone->n_points - 3].x =
786      FT_PIX_ROUND( zone->cur[zone->n_points - 3].x );
787    zone->cur[zone->n_points - 2].y =
788      FT_PIX_ROUND( zone->cur[zone->n_points - 2].y );
789    zone->cur[zone->n_points - 1].y =
790      FT_PIX_ROUND( zone->cur[zone->n_points - 1].y );
791
792#ifdef TT_USE_BYTECODE_INTERPRETER
793
794    if ( n_ins > 0 )
795    {
796      FT_Error  error;
797
798      FT_GlyphLoader  gloader         = loader->gloader;
799      FT_Outline      current_outline = gloader->current.outline;
800
801
802      TT_Set_CodeRange( loader->exec, tt_coderange_glyph,
803                        loader->exec->glyphIns, n_ins );
804
805      loader->exec->is_composite = is_composite;
806      loader->exec->pts          = *zone;
807
808      error = TT_Run_Context( loader->exec );
809      if ( error && loader->exec->pedantic_hinting )
810        return error;
811
812      /* store drop-out mode in bits 5-7; set bit 2 also as a marker */
813      current_outline.tags[0] |=
814        ( loader->exec->GS.scan_type << 5 ) | FT_CURVE_TAG_HAS_SCANMODE;
815    }
816
817#endif
818
819    /* save glyph phantom points */
820    loader->pp1 = zone->cur[zone->n_points - 4];
821    loader->pp2 = zone->cur[zone->n_points - 3];
822    loader->pp3 = zone->cur[zone->n_points - 2];
823    loader->pp4 = zone->cur[zone->n_points - 1];
824
825#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
826    if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
827    {
828      if ( loader->exec->sph_tweak_flags & SPH_TWEAK_DEEMBOLDEN )
829        FT_Outline_EmboldenXY( &loader->gloader->current.outline, -24, 0 );
830
831      else if ( loader->exec->sph_tweak_flags & SPH_TWEAK_EMBOLDEN )
832        FT_Outline_EmboldenXY( &loader->gloader->current.outline, 24, 0 );
833    }
834#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
835
836    return FT_Err_Ok;
837  }
838
839
840  /*************************************************************************/
841  /*                                                                       */
842  /* <Function>                                                            */
843  /*    TT_Process_Simple_Glyph                                            */
844  /*                                                                       */
845  /* <Description>                                                         */
846  /*    Once a simple glyph has been loaded, it needs to be processed.     */
847  /*    Usually, this means scaling and hinting through bytecode           */
848  /*    interpretation.                                                    */
849  /*                                                                       */
850  static FT_Error
851  TT_Process_Simple_Glyph( TT_Loader  loader )
852  {
853    FT_GlyphLoader  gloader = loader->gloader;
854    FT_Error        error   = FT_Err_Ok;
855    FT_Outline*     outline;
856    FT_Int          n_points;
857
858
859    outline  = &gloader->current.outline;
860    n_points = outline->n_points;
861
862    /* set phantom points */
863
864    outline->points[n_points    ] = loader->pp1;
865    outline->points[n_points + 1] = loader->pp2;
866    outline->points[n_points + 2] = loader->pp3;
867    outline->points[n_points + 3] = loader->pp4;
868
869    outline->tags[n_points    ] = 0;
870    outline->tags[n_points + 1] = 0;
871    outline->tags[n_points + 2] = 0;
872    outline->tags[n_points + 3] = 0;
873
874    n_points += 4;
875
876#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
877
878    if ( loader->face->doblend )
879    {
880      /* Deltas apply to the unscaled data. */
881      error = TT_Vary_Apply_Glyph_Deltas( loader->face,
882                                          loader->glyph_index,
883                                          outline,
884                                          (FT_UInt)n_points );
885      if ( error )
886        return error;
887    }
888
889#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
890
891    if ( IS_HINTED( loader->load_flags ) )
892    {
893      tt_prepare_zone( &loader->zone, &gloader->current, 0, 0 );
894
895      FT_ARRAY_COPY( loader->zone.orus, loader->zone.cur,
896                     loader->zone.n_points + 4 );
897    }
898
899    {
900#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
901      TT_Face    face   = loader->face;
902      TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
903
904      FT_String*  family         = face->root.family_name;
905      FT_UInt     ppem           = loader->size->metrics.x_ppem;
906      FT_String*  style          = face->root.style_name;
907      FT_UInt     x_scale_factor = 1000;
908#endif
909
910      FT_Vector*  vec   = outline->points;
911      FT_Vector*  limit = outline->points + n_points;
912
913      FT_Fixed  x_scale = 0; /* pacify compiler */
914      FT_Fixed  y_scale = 0;
915
916      FT_Bool  do_scale = FALSE;
917
918
919#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
920
921      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
922      {
923        /* scale, but only if enabled and only if TT hinting is being used */
924        if ( IS_HINTED( loader->load_flags ) )
925          x_scale_factor = sph_test_tweak_x_scaling( face,
926                                                     family,
927                                                     ppem,
928                                                     style,
929                                                     loader->glyph_index );
930        /* scale the glyph */
931        if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 ||
932             x_scale_factor != 1000                         )
933        {
934          x_scale = FT_MulDiv( loader->size->metrics.x_scale,
935                               (FT_Long)x_scale_factor, 1000 );
936          y_scale = loader->size->metrics.y_scale;
937
938          /* compensate for any scaling by de/emboldening; */
939          /* the amount was determined via experimentation */
940          if ( x_scale_factor != 1000 && ppem > 11 )
941            FT_Outline_EmboldenXY( outline,
942                                   FT_MulFix( 1280 * ppem,
943                                              1000 - x_scale_factor ),
944                                   0 );
945          do_scale = TRUE;
946        }
947      }
948      else
949
950#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
951
952      {
953        /* scale the glyph */
954        if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
955        {
956          x_scale = loader->size->metrics.x_scale;
957          y_scale = loader->size->metrics.y_scale;
958
959          do_scale = TRUE;
960        }
961      }
962
963      if ( do_scale )
964      {
965        for ( ; vec < limit; vec++ )
966        {
967          vec->x = FT_MulFix( vec->x, x_scale );
968          vec->y = FT_MulFix( vec->y, y_scale );
969        }
970
971        loader->pp1 = outline->points[n_points - 4];
972        loader->pp2 = outline->points[n_points - 3];
973        loader->pp3 = outline->points[n_points - 2];
974        loader->pp4 = outline->points[n_points - 1];
975      }
976    }
977
978    if ( IS_HINTED( loader->load_flags ) )
979    {
980      loader->zone.n_points += 4;
981
982      error = TT_Hint_Glyph( loader, 0 );
983    }
984
985    return error;
986  }
987
988
989  /*************************************************************************/
990  /*                                                                       */
991  /* <Function>                                                            */
992  /*    TT_Process_Composite_Component                                     */
993  /*                                                                       */
994  /* <Description>                                                         */
995  /*    Once a composite component has been loaded, it needs to be         */
996  /*    processed.  Usually, this means transforming and translating.      */
997  /*                                                                       */
998  static FT_Error
999  TT_Process_Composite_Component( TT_Loader    loader,
1000                                  FT_SubGlyph  subglyph,
1001                                  FT_UInt      start_point,
1002                                  FT_UInt      num_base_points )
1003  {
1004    FT_GlyphLoader  gloader = loader->gloader;
1005    FT_Outline      current;
1006    FT_Bool         have_scale;
1007    FT_Pos          x, y;
1008
1009
1010    current.points   = gloader->base.outline.points +
1011                         num_base_points;
1012    current.n_points = gloader->base.outline.n_points -
1013                         (short)num_base_points;
1014
1015    have_scale = FT_BOOL( subglyph->flags & ( WE_HAVE_A_SCALE     |
1016                                              WE_HAVE_AN_XY_SCALE |
1017                                              WE_HAVE_A_2X2       ) );
1018
1019    /* perform the transform required for this subglyph */
1020    if ( have_scale )
1021      FT_Outline_Transform( &current, &subglyph->transform );
1022
1023    /* get offset */
1024    if ( !( subglyph->flags & ARGS_ARE_XY_VALUES ) )
1025    {
1026      FT_UInt     num_points = (FT_UInt)gloader->base.outline.n_points;
1027      FT_UInt     k = (FT_UInt)subglyph->arg1;
1028      FT_UInt     l = (FT_UInt)subglyph->arg2;
1029      FT_Vector*  p1;
1030      FT_Vector*  p2;
1031
1032
1033      /* match l-th point of the newly loaded component to the k-th point */
1034      /* of the previously loaded components.                             */
1035
1036      /* change to the point numbers used by our outline */
1037      k += start_point;
1038      l += num_base_points;
1039      if ( k >= num_base_points ||
1040           l >= num_points      )
1041        return FT_THROW( Invalid_Composite );
1042
1043      p1 = gloader->base.outline.points + k;
1044      p2 = gloader->base.outline.points + l;
1045
1046      x = p1->x - p2->x;
1047      y = p1->y - p2->y;
1048    }
1049    else
1050    {
1051      x = subglyph->arg1;
1052      y = subglyph->arg2;
1053
1054      if ( !x && !y )
1055        return FT_Err_Ok;
1056
1057      /* Use a default value dependent on                                  */
1058      /* TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED.  This is useful for old */
1059      /* TT fonts which don't set the xxx_COMPONENT_OFFSET bit.            */
1060
1061      if ( have_scale &&
1062#ifdef TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED
1063           !( subglyph->flags & UNSCALED_COMPONENT_OFFSET ) )
1064#else
1065            ( subglyph->flags & SCALED_COMPONENT_OFFSET ) )
1066#endif
1067      {
1068
1069#if 0
1070
1071        /*******************************************************************/
1072        /*                                                                 */
1073        /* This algorithm is what Apple documents.  But it doesn't work.   */
1074        /*                                                                 */
1075        int  a = subglyph->transform.xx > 0 ?  subglyph->transform.xx
1076                                            : -subglyph->transform.xx;
1077        int  b = subglyph->transform.yx > 0 ?  subglyph->transform.yx
1078                                            : -subglyph->transform.yx;
1079        int  c = subglyph->transform.xy > 0 ?  subglyph->transform.xy
1080                                            : -subglyph->transform.xy;
1081        int  d = subglyph->transform.yy > 0 ? subglyph->transform.yy
1082                                            : -subglyph->transform.yy;
1083        int  m = a > b ? a : b;
1084        int  n = c > d ? c : d;
1085
1086
1087        if ( a - b <= 33 && a - b >= -33 )
1088          m *= 2;
1089        if ( c - d <= 33 && c - d >= -33 )
1090          n *= 2;
1091        x = FT_MulFix( x, m );
1092        y = FT_MulFix( y, n );
1093
1094#else /* 1 */
1095
1096        /*******************************************************************/
1097        /*                                                                 */
1098        /* This algorithm is a guess and works much better than the above. */
1099        /*                                                                 */
1100        FT_Fixed  mac_xscale = FT_Hypot( subglyph->transform.xx,
1101                                         subglyph->transform.xy );
1102        FT_Fixed  mac_yscale = FT_Hypot( subglyph->transform.yy,
1103                                         subglyph->transform.yx );
1104
1105
1106        x = FT_MulFix( x, mac_xscale );
1107        y = FT_MulFix( y, mac_yscale );
1108
1109#endif /* 1 */
1110
1111      }
1112
1113      if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
1114      {
1115        FT_Fixed  x_scale = loader->size->metrics.x_scale;
1116        FT_Fixed  y_scale = loader->size->metrics.y_scale;
1117
1118
1119        x = FT_MulFix( x, x_scale );
1120        y = FT_MulFix( y, y_scale );
1121
1122        if ( subglyph->flags & ROUND_XY_TO_GRID )
1123        {
1124          x = FT_PIX_ROUND( x );
1125          y = FT_PIX_ROUND( y );
1126        }
1127      }
1128    }
1129
1130    if ( x || y )
1131      FT_Outline_Translate( &current, x, y );
1132
1133    return FT_Err_Ok;
1134  }
1135
1136
1137  /*************************************************************************/
1138  /*                                                                       */
1139  /* <Function>                                                            */
1140  /*    TT_Process_Composite_Glyph                                         */
1141  /*                                                                       */
1142  /* <Description>                                                         */
1143  /*    This is slightly different from TT_Process_Simple_Glyph, in that   */
1144  /*    its sole purpose is to hint the glyph.  Thus this function is      */
1145  /*    only available when bytecode interpreter is enabled.               */
1146  /*                                                                       */
1147  static FT_Error
1148  TT_Process_Composite_Glyph( TT_Loader  loader,
1149                              FT_UInt    start_point,
1150                              FT_UInt    start_contour )
1151  {
1152    FT_Error     error;
1153    FT_Outline*  outline;
1154    FT_UInt      i;
1155
1156
1157    outline = &loader->gloader->base.outline;
1158
1159    /* make room for phantom points */
1160    error = FT_GLYPHLOADER_CHECK_POINTS( loader->gloader,
1161                                         outline->n_points + 4,
1162                                         0 );
1163    if ( error )
1164      return error;
1165
1166    outline->points[outline->n_points    ] = loader->pp1;
1167    outline->points[outline->n_points + 1] = loader->pp2;
1168    outline->points[outline->n_points + 2] = loader->pp3;
1169    outline->points[outline->n_points + 3] = loader->pp4;
1170
1171    outline->tags[outline->n_points    ] = 0;
1172    outline->tags[outline->n_points + 1] = 0;
1173    outline->tags[outline->n_points + 2] = 0;
1174    outline->tags[outline->n_points + 3] = 0;
1175
1176#ifdef TT_USE_BYTECODE_INTERPRETER
1177
1178    {
1179      FT_Stream  stream = loader->stream;
1180      FT_UShort  n_ins, max_ins;
1181      FT_ULong   tmp;
1182
1183
1184      /* TT_Load_Composite_Glyph only gives us the offset of instructions */
1185      /* so we read them here                                             */
1186      if ( FT_STREAM_SEEK( loader->ins_pos ) ||
1187           FT_READ_USHORT( n_ins )           )
1188        return error;
1189
1190      FT_TRACE5(( "  Instructions size = %d\n", n_ins ));
1191
1192      /* check it */
1193      max_ins = loader->face->max_profile.maxSizeOfInstructions;
1194      if ( n_ins > max_ins )
1195      {
1196        /* don't trust `maxSizeOfInstructions'; */
1197        /* only do a rough safety check         */
1198        if ( (FT_Int)n_ins > loader->byte_len )
1199        {
1200          FT_TRACE1(( "TT_Process_Composite_Glyph:"
1201                      " too many instructions (%d) for glyph with length %d\n",
1202                      n_ins, loader->byte_len ));
1203          return FT_THROW( Too_Many_Hints );
1204        }
1205
1206        tmp   = loader->exec->glyphSize;
1207        error = Update_Max( loader->exec->memory,
1208                            &tmp,
1209                            sizeof ( FT_Byte ),
1210                            (void*)&loader->exec->glyphIns,
1211                            n_ins );
1212
1213        loader->exec->glyphSize = (FT_UShort)tmp;
1214        if ( error )
1215          return error;
1216      }
1217      else if ( n_ins == 0 )
1218        return FT_Err_Ok;
1219
1220      if ( FT_STREAM_READ( loader->exec->glyphIns, n_ins ) )
1221        return error;
1222
1223      loader->glyph->control_data = loader->exec->glyphIns;
1224      loader->glyph->control_len  = n_ins;
1225    }
1226
1227#endif
1228
1229    tt_prepare_zone( &loader->zone, &loader->gloader->base,
1230                     start_point, start_contour );
1231
1232    /* Some points are likely touched during execution of  */
1233    /* instructions on components.  So let's untouch them. */
1234    for ( i = 0; i < loader->zone.n_points; i++ )
1235      loader->zone.tags[i] &= ~FT_CURVE_TAG_TOUCH_BOTH;
1236
1237    loader->zone.n_points += 4;
1238
1239    return TT_Hint_Glyph( loader, 1 );
1240  }
1241
1242
1243  /*
1244   * Calculate the phantom points
1245   *
1246   * Defining the right side bearing (rsb) as
1247   *
1248   *   rsb = aw - (lsb + xmax - xmin)
1249   *
1250   * (with `aw' the advance width, `lsb' the left side bearing, and `xmin'
1251   * and `xmax' the glyph's minimum and maximum x value), the OpenType
1252   * specification defines the initial position of horizontal phantom points
1253   * as
1254   *
1255   *   pp1 = (round(xmin - lsb), 0)      ,
1256   *   pp2 = (round(pp1 + aw), 0)        .
1257   *
1258   * Note that the rounding to the grid (in the device space) is not
1259   * documented currently in the specification.
1260   *
1261   * However, the specification lacks the precise definition of vertical
1262   * phantom points.  Greg Hitchcock provided the following explanation.
1263   *
1264   * - a `vmtx' table is present
1265   *
1266   *   For any glyph, the minimum and maximum y values (`ymin' and `ymax')
1267   *   are given in the `glyf' table, the top side bearing (tsb) and advance
1268   *   height (ah) are given in the `vmtx' table.  The bottom side bearing
1269   *   (bsb) is then calculated as
1270   *
1271   *     bsb = ah - (tsb + ymax - ymin)       ,
1272   *
1273   *   and the initial position of vertical phantom points is
1274   *
1275   *     pp3 = (x, round(ymax + tsb))       ,
1276   *     pp4 = (x, round(pp3 - ah))         .
1277   *
1278   *   See below for value `x'.
1279   *
1280   * - no `vmtx' table in the font
1281   *
1282   *   If there is an `OS/2' table, we set
1283   *
1284   *     DefaultAscender = sTypoAscender       ,
1285   *     DefaultDescender = sTypoDescender     ,
1286   *
1287   *   otherwise we use data from the `hhea' table:
1288   *
1289   *     DefaultAscender = Ascender         ,
1290   *     DefaultDescender = Descender       .
1291   *
1292   *   With these two variables we can now set
1293   *
1294   *     ah = DefaultAscender - sDefaultDescender    ,
1295   *     tsb = DefaultAscender - yMax                ,
1296   *
1297   *   and proceed as if a `vmtx' table was present.
1298   *
1299   * Usually we have
1300   *
1301   *   x = aw / 2      ,                                                (1)
1302   *
1303   * but there is one compatibility case where it can be set to
1304   *
1305   *   x = -DefaultDescender -
1306   *         ((DefaultAscender - DefaultDescender - aw) / 2)     .      (2)
1307   *
1308   * and another one with
1309   *
1310   *   x = 0     .                                                      (3)
1311   *
1312   * In Windows, the history of those values is quite complicated,
1313   * depending on the hinting engine (that is, the graphics framework).
1314   *
1315   *   framework        from                 to       formula
1316   *  ----------------------------------------------------------
1317   *    GDI       Windows 98               current      (1)
1318   *              (Windows 2000 for NT)
1319   *    GDI+      Windows XP               Windows 7    (2)
1320   *    GDI+      Windows 8                current      (3)
1321   *    DWrite    Windows 7                current      (3)
1322   *
1323   * For simplicity, FreeType uses (1) for grayscale subpixel hinting and
1324   * (3) for everything else.
1325   *
1326   */
1327#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
1328
1329#define TT_LOADER_SET_PP( loader )                                          \
1330          do                                                                \
1331          {                                                                 \
1332            FT_Bool  subpixel_hinting_ = loader->exec                       \
1333                                           ? loader->exec->subpixel_hinting \
1334                                           : 0;                             \
1335            FT_Bool  grayscale_        = loader->exec                       \
1336                                           ? loader->exec->grayscale        \
1337                                           : 0;                             \
1338            FT_Bool  use_aw_2_         = (FT_Bool)( subpixel_hinting_ &&    \
1339                                                    grayscale_        );    \
1340                                                                            \
1341                                                                            \
1342            (loader)->pp1.x = (loader)->bbox.xMin - (loader)->left_bearing; \
1343            (loader)->pp1.y = 0;                                            \
1344            (loader)->pp2.x = (loader)->pp1.x + (loader)->advance;          \
1345            (loader)->pp2.y = 0;                                            \
1346                                                                            \
1347            (loader)->pp3.x = use_aw_2_ ? (loader)->advance / 2 : 0;        \
1348            (loader)->pp3.y = (loader)->bbox.yMax + (loader)->top_bearing;  \
1349            (loader)->pp4.x = use_aw_2_ ? (loader)->advance / 2 : 0;        \
1350            (loader)->pp4.y = (loader)->pp3.y - (loader)->vadvance;         \
1351          } while ( 0 )
1352
1353#else /* !TT_CONFIG_OPTION_SUBPIXEL_HINTING */
1354
1355#define TT_LOADER_SET_PP( loader )                                          \
1356          do                                                                \
1357          {                                                                 \
1358            (loader)->pp1.x = (loader)->bbox.xMin - (loader)->left_bearing; \
1359            (loader)->pp1.y = 0;                                            \
1360            (loader)->pp2.x = (loader)->pp1.x + (loader)->advance;          \
1361            (loader)->pp2.y = 0;                                            \
1362                                                                            \
1363            (loader)->pp3.x = 0;                                            \
1364            (loader)->pp3.y = (loader)->bbox.yMax + (loader)->top_bearing;  \
1365            (loader)->pp4.x = 0;                                            \
1366            (loader)->pp4.y = (loader)->pp3.y - (loader)->vadvance;         \
1367          } while ( 0 )
1368
1369#endif /* !TT_CONFIG_OPTION_SUBPIXEL_HINTING */
1370
1371
1372  /* a utility function to retrieve i-th node from given FT_List */
1373  static FT_ListNode
1374  ft_list_get_node_at( FT_List  list,
1375                       FT_UInt  index )
1376  {
1377    FT_ListNode  cur;
1378
1379
1380    if ( !list )
1381      return NULL;
1382
1383    for ( cur = list->head; cur; cur = cur->next )
1384    {
1385      if ( !index )
1386        return cur;
1387
1388      index --;
1389    }
1390
1391    return NULL;
1392  }
1393
1394
1395  /*************************************************************************/
1396  /*                                                                       */
1397  /* <Function>                                                            */
1398  /*    load_truetype_glyph                                                */
1399  /*                                                                       */
1400  /* <Description>                                                         */
1401  /*    Loads a given truetype glyph.  Handles composites and uses a       */
1402  /*    TT_Loader object.                                                  */
1403  /*                                                                       */
1404  static FT_Error
1405  load_truetype_glyph( TT_Loader  loader,
1406                       FT_UInt    glyph_index,
1407                       FT_UInt    recurse_count,
1408                       FT_Bool    header_only )
1409  {
1410    FT_Error        error        = FT_Err_Ok;
1411    FT_Fixed        x_scale, y_scale;
1412    FT_ULong        offset;
1413    TT_Face         face         = loader->face;
1414    FT_GlyphLoader  gloader      = loader->gloader;
1415    FT_Bool         opened_frame = 0;
1416
1417#ifdef FT_CONFIG_OPTION_INCREMENTAL
1418    FT_StreamRec    inc_stream;
1419    FT_Data         glyph_data;
1420    FT_Bool         glyph_data_loaded = 0;
1421#endif
1422
1423
1424#ifdef FT_DEBUG_LEVEL_TRACE
1425    if ( recurse_count )
1426      FT_TRACE5(( "  nesting level: %d\n", recurse_count ));
1427#endif
1428
1429    /* some fonts have an incorrect value of `maxComponentDepth', */
1430    /* thus we allow depth 1 to catch the majority of them        */
1431    if ( recurse_count > 1                                   &&
1432         recurse_count > face->max_profile.maxComponentDepth )
1433    {
1434      error = FT_THROW( Invalid_Composite );
1435      goto Exit;
1436    }
1437
1438#ifndef FT_CONFIG_OPTION_INCREMENTAL
1439    /* check glyph index */
1440    if ( glyph_index >= (FT_UInt)face->root.num_glyphs )
1441    {
1442      error = FT_THROW( Invalid_Glyph_Index );
1443      goto Exit;
1444    }
1445#endif
1446
1447    loader->glyph_index = glyph_index;
1448
1449    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
1450    {
1451      x_scale = loader->size->metrics.x_scale;
1452      y_scale = loader->size->metrics.y_scale;
1453    }
1454    else
1455    {
1456      x_scale = 0x10000L;
1457      y_scale = 0x10000L;
1458    }
1459
1460    /* Set `offset' to the start of the glyph relative to the start of */
1461    /* the `glyf' table, and `byte_len' to the length of the glyph in  */
1462    /* bytes.                                                          */
1463
1464#ifdef FT_CONFIG_OPTION_INCREMENTAL
1465
1466    /* If we are loading glyph data via the incremental interface, set */
1467    /* the loader stream to a memory stream reading the data returned  */
1468    /* by the interface.                                               */
1469    if ( face->root.internal->incremental_interface )
1470    {
1471      error = face->root.internal->incremental_interface->funcs->get_glyph_data(
1472                face->root.internal->incremental_interface->object,
1473                glyph_index, &glyph_data );
1474      if ( error )
1475        goto Exit;
1476
1477      glyph_data_loaded = 1;
1478      offset            = 0;
1479      loader->byte_len  = glyph_data.length;
1480
1481      FT_MEM_ZERO( &inc_stream, sizeof ( inc_stream ) );
1482      FT_Stream_OpenMemory( &inc_stream,
1483                            glyph_data.pointer,
1484                            (FT_ULong)glyph_data.length );
1485
1486      loader->stream = &inc_stream;
1487    }
1488    else
1489
1490#endif /* FT_CONFIG_OPTION_INCREMENTAL */
1491
1492      offset = tt_face_get_location( face, glyph_index,
1493                                     (FT_UInt*)&loader->byte_len );
1494
1495    if ( loader->byte_len > 0 )
1496    {
1497#ifdef FT_CONFIG_OPTION_INCREMENTAL
1498      /* for the incremental interface, `glyf_offset' is always zero */
1499      if ( !loader->glyf_offset                        &&
1500           !face->root.internal->incremental_interface )
1501#else
1502      if ( !loader->glyf_offset )
1503#endif /* FT_CONFIG_OPTION_INCREMENTAL */
1504      {
1505        FT_TRACE2(( "no `glyf' table but non-zero `loca' entry\n" ));
1506        error = FT_THROW( Invalid_Table );
1507        goto Exit;
1508      }
1509
1510      error = face->access_glyph_frame( loader, glyph_index,
1511                                        loader->glyf_offset + offset,
1512                                        (FT_UInt)loader->byte_len );
1513      if ( error )
1514        goto Exit;
1515
1516      opened_frame = 1;
1517
1518      /* read glyph header first */
1519      error = face->read_glyph_header( loader );
1520      if ( error )
1521        goto Exit;
1522
1523      /* the metrics must be computed after loading the glyph header */
1524      /* since we need the glyph's `yMax' value in case the vertical */
1525      /* metrics must be emulated                                    */
1526      error = tt_get_metrics( loader, glyph_index );
1527      if ( error )
1528        goto Exit;
1529
1530      if ( header_only )
1531        goto Exit;
1532    }
1533
1534    if ( loader->byte_len == 0 || loader->n_contours == 0 )
1535    {
1536      loader->bbox.xMin = 0;
1537      loader->bbox.xMax = 0;
1538      loader->bbox.yMin = 0;
1539      loader->bbox.yMax = 0;
1540
1541      error = tt_get_metrics( loader, glyph_index );
1542      if ( error )
1543        goto Exit;
1544
1545      if ( header_only )
1546        goto Exit;
1547
1548      /* must initialize points before (possibly) overriding */
1549      /* glyph metrics from the incremental interface        */
1550      TT_LOADER_SET_PP( loader );
1551
1552#ifdef FT_CONFIG_OPTION_INCREMENTAL
1553      tt_get_metrics_incr_overrides( loader, glyph_index );
1554#endif
1555
1556#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
1557
1558      if ( loader->face->doblend )
1559      {
1560        /* a small outline structure with four elements for */
1561        /* communication with `TT_Vary_Apply_Glyph_Deltas'  */
1562        FT_Vector   points[4];
1563        char        tags[4]     = { 1, 1, 1, 1 };
1564        short       contours[4] = { 0, 1, 2, 3 };
1565        FT_Outline  outline;
1566
1567
1568        points[0].x = loader->pp1.x;
1569        points[0].y = loader->pp1.y;
1570        points[1].x = loader->pp2.x;
1571        points[1].y = loader->pp2.y;
1572
1573        points[2].x = loader->pp3.x;
1574        points[2].y = loader->pp3.y;
1575        points[3].x = loader->pp4.x;
1576        points[3].y = loader->pp4.y;
1577
1578        outline.n_points   = 4;
1579        outline.n_contours = 4;
1580        outline.points     = points;
1581        outline.tags       = tags;
1582        outline.contours   = contours;
1583
1584        /* this must be done before scaling */
1585        error = TT_Vary_Apply_Glyph_Deltas( loader->face,
1586                                            glyph_index,
1587                                            &outline,
1588                                            (FT_UInt)outline.n_points );
1589        if ( error )
1590          goto Exit;
1591
1592        loader->pp1.x = points[0].x;
1593        loader->pp1.y = points[0].y;
1594        loader->pp2.x = points[1].x;
1595        loader->pp2.y = points[1].y;
1596
1597        loader->pp3.x = points[2].x;
1598        loader->pp3.y = points[2].y;
1599        loader->pp4.x = points[3].x;
1600        loader->pp4.y = points[3].y;
1601      }
1602
1603#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
1604
1605      /* scale phantom points, if necessary; */
1606      /* they get rounded in `TT_Hint_Glyph' */
1607      if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
1608      {
1609        loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
1610        loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
1611        /* pp1.y and pp2.y are always zero */
1612
1613        loader->pp3.x = FT_MulFix( loader->pp3.x, x_scale );
1614        loader->pp3.y = FT_MulFix( loader->pp3.y, y_scale );
1615        loader->pp4.x = FT_MulFix( loader->pp4.x, x_scale );
1616        loader->pp4.y = FT_MulFix( loader->pp4.y, y_scale );
1617      }
1618
1619      error = FT_Err_Ok;
1620      goto Exit;
1621    }
1622
1623    /* must initialize phantom points before (possibly) overriding */
1624    /* glyph metrics from the incremental interface                */
1625    TT_LOADER_SET_PP( loader );
1626
1627#ifdef FT_CONFIG_OPTION_INCREMENTAL
1628    tt_get_metrics_incr_overrides( loader, glyph_index );
1629#endif
1630
1631    /***********************************************************************/
1632    /***********************************************************************/
1633    /***********************************************************************/
1634
1635    /* if it is a simple glyph, load it */
1636
1637    if ( loader->n_contours > 0 )
1638    {
1639      error = face->read_simple_glyph( loader );
1640      if ( error )
1641        goto Exit;
1642
1643      /* all data have been read */
1644      face->forget_glyph_frame( loader );
1645      opened_frame = 0;
1646
1647      error = TT_Process_Simple_Glyph( loader );
1648      if ( error )
1649        goto Exit;
1650
1651      FT_GlyphLoader_Add( gloader );
1652    }
1653
1654    /***********************************************************************/
1655    /***********************************************************************/
1656    /***********************************************************************/
1657
1658    /* otherwise, load a composite! */
1659    else if ( loader->n_contours == -1 )
1660    {
1661      FT_Memory  memory = face->root.memory;
1662
1663      FT_UInt   start_point;
1664      FT_UInt   start_contour;
1665      FT_ULong  ins_pos;  /* position of composite instructions, if any */
1666      FT_ListNode  node, node2;
1667
1668
1669      /*
1670       * We store the glyph index directly in the `node->data' pointer,
1671       * following the glib solution (cf. macro `GUINT_TO_POINTER') with a
1672       * double cast to make this portable.  Note, however, that this needs
1673       * pointers with a width of at least 32 bits.
1674       */
1675
1676
1677      /* clear the nodes filled by sibling chains */
1678      node = ft_list_get_node_at( &loader->composites, recurse_count );
1679      for ( node2 = node ; node2 ; node2 = node2->next )
1680        node2->data = (void*)ULONG_MAX;
1681
1682
1683      /* check whether we already have a composite glyph with this index */
1684      if ( FT_List_Find( &loader->composites,
1685                         (void*)(unsigned long)glyph_index ) )
1686      {
1687        FT_TRACE1(( "TT_Load_Composite_Glyph:"
1688                    " infinite recursion detected\n" ));
1689        error = FT_THROW( Invalid_Composite );
1690        goto Exit;
1691      }
1692      else if ( node )
1693      {
1694        node->data = (void*)(unsigned long)glyph_index;
1695      }
1696      else
1697      {
1698        if ( FT_NEW( node ) )
1699          goto Exit;
1700        node->data = (void*)(unsigned long)glyph_index;
1701        FT_List_Add( &loader->composites, node );
1702      }
1703
1704      start_point   = (FT_UInt)gloader->base.outline.n_points;
1705      start_contour = (FT_UInt)gloader->base.outline.n_contours;
1706
1707      /* for each subglyph, read composite header */
1708      error = face->read_composite_glyph( loader );
1709      if ( error )
1710        goto Exit;
1711
1712      /* store the offset of instructions */
1713      ins_pos = loader->ins_pos;
1714
1715      /* all data we need are read */
1716      face->forget_glyph_frame( loader );
1717      opened_frame = 0;
1718
1719#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
1720
1721      if ( face->doblend )
1722      {
1723        short        i, limit;
1724        FT_SubGlyph  subglyph;
1725
1726        FT_Outline  outline;
1727        FT_Vector*  points   = NULL;
1728        char*       tags     = NULL;
1729        short*      contours = NULL;
1730
1731
1732        limit = (short)gloader->current.num_subglyphs;
1733
1734        /* construct an outline structure for              */
1735        /* communication with `TT_Vary_Apply_Glyph_Deltas' */
1736        outline.n_points   = (short)( gloader->current.num_subglyphs + 4 );
1737        outline.n_contours = outline.n_points;
1738
1739        outline.tags     = NULL;
1740        outline.contours = NULL;
1741
1742        if ( FT_NEW_ARRAY( points, outline.n_points )   ||
1743             FT_NEW_ARRAY( tags, outline.n_points )     ||
1744             FT_NEW_ARRAY( contours, outline.n_points ) )
1745          goto Exit1;
1746
1747        subglyph = gloader->current.subglyphs;
1748
1749        for ( i = 0; i < limit; i++, subglyph++ )
1750        {
1751          /* applying deltas for anchor points doesn't make sense, */
1752          /* but we don't have to specially check this since       */
1753          /* unused delta values are zero anyways                  */
1754          points[i].x = subglyph->arg1;
1755          points[i].y = subglyph->arg2;
1756          tags[i]     = 1;
1757          contours[i] = i;
1758        }
1759
1760        points[i].x = loader->pp1.x;
1761        points[i].y = loader->pp1.y;
1762        tags[i]     = 1;
1763        contours[i] = i;
1764
1765        i++;
1766        points[i].x = loader->pp2.x;
1767        points[i].y = loader->pp2.y;
1768        tags[i]     = 1;
1769        contours[i] = i;
1770
1771        i++;
1772        points[i].x = loader->pp3.x;
1773        points[i].y = loader->pp3.y;
1774        tags[i]     = 1;
1775        contours[i] = i;
1776
1777        i++;
1778        points[i].x = loader->pp4.x;
1779        points[i].y = loader->pp4.y;
1780        tags[i]     = 1;
1781        contours[i] = i;
1782
1783        outline.points   = points;
1784        outline.tags     = tags;
1785        outline.contours = contours;
1786
1787        /* this call provides additional offsets */
1788        /* for each component's translation      */
1789        if ( ( error = TT_Vary_Apply_Glyph_Deltas(
1790                         face,
1791                         glyph_index,
1792                         &outline,
1793                         (FT_UInt)outline.n_points ) ) != 0 )
1794          goto Exit1;
1795
1796        subglyph = gloader->current.subglyphs;
1797
1798        for ( i = 0; i < limit; i++, subglyph++ )
1799        {
1800          /* XXX: overflow check for subglyph->{arg1,arg2}.         */
1801          /*      Deltas must be within signed 16-bit,              */
1802          /*      but the restriction of summed deltas is not clear */
1803          subglyph->arg1 = (FT_Int16)points[i].x;
1804          subglyph->arg2 = (FT_Int16)points[i].y;
1805        }
1806
1807        loader->pp1.x = points[i + 0].x;
1808        loader->pp1.y = points[i + 0].y;
1809        loader->pp2.x = points[i + 1].x;
1810        loader->pp2.y = points[i + 1].y;
1811
1812        loader->pp3.x = points[i + 2].x;
1813        loader->pp3.y = points[i + 2].y;
1814        loader->pp4.x = points[i + 3].x;
1815        loader->pp4.y = points[i + 3].y;
1816
1817      Exit1:
1818        FT_FREE( outline.points );
1819        FT_FREE( outline.tags );
1820        FT_FREE( outline.contours );
1821
1822        if ( error )
1823          goto Exit;
1824      }
1825
1826#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
1827
1828      /* scale phantom points, if necessary; */
1829      /* they get rounded in `TT_Hint_Glyph' */
1830      if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
1831      {
1832        loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
1833        loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
1834        /* pp1.y and pp2.y are always zero */
1835
1836        loader->pp3.x = FT_MulFix( loader->pp3.x, x_scale );
1837        loader->pp3.y = FT_MulFix( loader->pp3.y, y_scale );
1838        loader->pp4.x = FT_MulFix( loader->pp4.x, x_scale );
1839        loader->pp4.y = FT_MulFix( loader->pp4.y, y_scale );
1840      }
1841
1842      /* if the flag FT_LOAD_NO_RECURSE is set, we return the subglyph */
1843      /* `as is' in the glyph slot (the client application will be     */
1844      /* responsible for interpreting these data)...                   */
1845      if ( loader->load_flags & FT_LOAD_NO_RECURSE )
1846      {
1847        FT_GlyphLoader_Add( gloader );
1848        loader->glyph->format = FT_GLYPH_FORMAT_COMPOSITE;
1849
1850        goto Exit;
1851      }
1852
1853      /*********************************************************************/
1854      /*********************************************************************/
1855      /*********************************************************************/
1856
1857      {
1858        FT_UInt      n, num_base_points;
1859        FT_SubGlyph  subglyph       = NULL;
1860
1861        FT_UInt      num_points     = start_point;
1862        FT_UInt      num_subglyphs  = gloader->current.num_subglyphs;
1863        FT_UInt      num_base_subgs = gloader->base.num_subglyphs;
1864
1865        FT_Stream    old_stream     = loader->stream;
1866        FT_Int       old_byte_len   = loader->byte_len;
1867
1868
1869        FT_GlyphLoader_Add( gloader );
1870
1871        /* read each subglyph independently */
1872        for ( n = 0; n < num_subglyphs; n++ )
1873        {
1874          FT_Vector  pp[4];
1875
1876
1877          /* Each time we call load_truetype_glyph in this loop, the   */
1878          /* value of `gloader.base.subglyphs' can change due to table */
1879          /* reallocations.  We thus need to recompute the subglyph    */
1880          /* pointer on each iteration.                                */
1881          subglyph = gloader->base.subglyphs + num_base_subgs + n;
1882
1883          pp[0] = loader->pp1;
1884          pp[1] = loader->pp2;
1885          pp[2] = loader->pp3;
1886          pp[3] = loader->pp4;
1887
1888          num_base_points = (FT_UInt)gloader->base.outline.n_points;
1889
1890          error = load_truetype_glyph( loader,
1891                                       (FT_UInt)subglyph->index,
1892                                       recurse_count + 1,
1893                                       FALSE );
1894          if ( error )
1895            goto Exit;
1896
1897          /* restore subglyph pointer */
1898          subglyph = gloader->base.subglyphs + num_base_subgs + n;
1899
1900          /* restore phantom points if necessary */
1901          if ( !( subglyph->flags & USE_MY_METRICS ) )
1902          {
1903            loader->pp1 = pp[0];
1904            loader->pp2 = pp[1];
1905            loader->pp3 = pp[2];
1906            loader->pp4 = pp[3];
1907          }
1908
1909          num_points = (FT_UInt)gloader->base.outline.n_points;
1910
1911          if ( num_points == num_base_points )
1912            continue;
1913
1914          /* gloader->base.outline consists of three parts:               */
1915          /* 0 -(1)-> start_point -(2)-> num_base_points -(3)-> n_points. */
1916          /*                                                              */
1917          /* (1): exists from the beginning                               */
1918          /* (2): components that have been loaded so far                 */
1919          /* (3): the newly loaded component                              */
1920          error = TT_Process_Composite_Component( loader,
1921                                                  subglyph,
1922                                                  start_point,
1923                                                  num_base_points );
1924          if ( error )
1925            goto Exit;
1926        }
1927
1928        loader->stream   = old_stream;
1929        loader->byte_len = old_byte_len;
1930
1931        /* process the glyph */
1932        loader->ins_pos = ins_pos;
1933        if ( IS_HINTED( loader->load_flags ) &&
1934#ifdef TT_USE_BYTECODE_INTERPRETER
1935             subglyph->flags & WE_HAVE_INSTR &&
1936#endif
1937             num_points > start_point )
1938        {
1939          error = TT_Process_Composite_Glyph( loader,
1940                                              start_point,
1941                                              start_contour );
1942          if ( error )
1943            goto Exit;
1944        }
1945      }
1946    }
1947    else
1948    {
1949      /* invalid composite count (negative but not -1) */
1950      error = FT_THROW( Invalid_Outline );
1951      goto Exit;
1952    }
1953
1954    /***********************************************************************/
1955    /***********************************************************************/
1956    /***********************************************************************/
1957
1958  Exit:
1959
1960    if ( opened_frame )
1961      face->forget_glyph_frame( loader );
1962
1963#ifdef FT_CONFIG_OPTION_INCREMENTAL
1964
1965    if ( glyph_data_loaded )
1966      face->root.internal->incremental_interface->funcs->free_glyph_data(
1967        face->root.internal->incremental_interface->object,
1968        &glyph_data );
1969
1970#endif
1971
1972    return error;
1973  }
1974
1975
1976  static FT_Error
1977  compute_glyph_metrics( TT_Loader  loader,
1978                         FT_UInt    glyph_index )
1979  {
1980    TT_Face    face   = loader->face;
1981#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
1982    TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
1983#endif
1984
1985    FT_BBox       bbox;
1986    FT_Fixed      y_scale;
1987    TT_GlyphSlot  glyph = loader->glyph;
1988    TT_Size       size  = loader->size;
1989
1990
1991    y_scale = 0x10000L;
1992    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
1993      y_scale = size->root.metrics.y_scale;
1994
1995    if ( glyph->format != FT_GLYPH_FORMAT_COMPOSITE )
1996      FT_Outline_Get_CBox( &glyph->outline, &bbox );
1997    else
1998      bbox = loader->bbox;
1999
2000    /* get the device-independent horizontal advance; it is scaled later */
2001    /* by the base layer.                                                */
2002    glyph->linearHoriAdvance = loader->linear;
2003
2004    glyph->metrics.horiBearingX = bbox.xMin;
2005    glyph->metrics.horiBearingY = bbox.yMax;
2006    glyph->metrics.horiAdvance  = loader->pp2.x - loader->pp1.x;
2007
2008    /* adjust advance width to the value contained in the hdmx table */
2009    /* unless FT_LOAD_COMPUTE_METRICS is set                         */
2010    if ( !face->postscript.isFixedPitch                    &&
2011         IS_HINTED( loader->load_flags )                   &&
2012         !( loader->load_flags & FT_LOAD_COMPUTE_METRICS ) )
2013    {
2014      FT_Byte*  widthp;
2015
2016
2017      widthp = tt_face_get_device_metrics( face,
2018                                           size->root.metrics.x_ppem,
2019                                           glyph_index );
2020
2021#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
2022
2023      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
2024      {
2025        FT_Bool  ignore_x_mode;
2026
2027
2028        ignore_x_mode = FT_BOOL( FT_LOAD_TARGET_MODE( loader->load_flags ) !=
2029                                 FT_RENDER_MODE_MONO );
2030
2031        if ( widthp                                                   &&
2032             ( ( ignore_x_mode && loader->exec->compatible_widths ) ||
2033                !ignore_x_mode                                      ||
2034                SPH_OPTION_BITMAP_WIDTHS                            ) )
2035          glyph->metrics.horiAdvance = *widthp * 64;
2036      }
2037      else
2038
2039#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
2040
2041      {
2042        if ( widthp )
2043          glyph->metrics.horiAdvance = *widthp * 64;
2044      }
2045    }
2046
2047    /* set glyph dimensions */
2048    glyph->metrics.width  = bbox.xMax - bbox.xMin;
2049    glyph->metrics.height = bbox.yMax - bbox.yMin;
2050
2051    /* Now take care of vertical metrics.  In the case where there is */
2052    /* no vertical information within the font (relatively common),   */
2053    /* create some metrics manually                                   */
2054    {
2055      FT_Pos  top;      /* scaled vertical top side bearing  */
2056      FT_Pos  advance;  /* scaled vertical advance height    */
2057
2058
2059      /* Get the unscaled top bearing and advance height. */
2060      if ( face->vertical_info                   &&
2061           face->vertical.number_Of_VMetrics > 0 )
2062      {
2063        top = (FT_Short)FT_DivFix( loader->pp3.y - bbox.yMax,
2064                                   y_scale );
2065
2066        if ( loader->pp3.y <= loader->pp4.y )
2067          advance = 0;
2068        else
2069          advance = (FT_UShort)FT_DivFix( loader->pp3.y - loader->pp4.y,
2070                                          y_scale );
2071      }
2072      else
2073      {
2074        FT_Pos  height;
2075
2076
2077        /* XXX Compute top side bearing and advance height in  */
2078        /*     Get_VMetrics instead of here.                   */
2079
2080        /* NOTE: The OS/2 values are the only `portable' ones, */
2081        /*       which is why we use them, if there is an OS/2 */
2082        /*       table in the font.  Otherwise, we use the     */
2083        /*       values defined in the horizontal header.      */
2084
2085        height = (FT_Short)FT_DivFix( bbox.yMax - bbox.yMin,
2086                                      y_scale );
2087        if ( face->os2.version != 0xFFFFU )
2088          advance = (FT_Pos)( face->os2.sTypoAscender -
2089                              face->os2.sTypoDescender );
2090        else
2091          advance = (FT_Pos)( face->horizontal.Ascender -
2092                              face->horizontal.Descender );
2093
2094        top = ( advance - height ) / 2;
2095      }
2096
2097#ifdef FT_CONFIG_OPTION_INCREMENTAL
2098      {
2099        FT_Incremental_InterfaceRec*  incr;
2100        FT_Incremental_MetricsRec     metrics;
2101        FT_Error                      error;
2102
2103
2104        incr = face->root.internal->incremental_interface;
2105
2106        /* If this is an incrementally loaded font see if there are */
2107        /* overriding metrics for this glyph.                       */
2108        if ( incr && incr->funcs->get_glyph_metrics )
2109        {
2110          metrics.bearing_x = 0;
2111          metrics.bearing_y = top;
2112          metrics.advance   = advance;
2113
2114          error = incr->funcs->get_glyph_metrics( incr->object,
2115                                                  glyph_index,
2116                                                  TRUE,
2117                                                  &metrics );
2118          if ( error )
2119            return error;
2120
2121          top     = metrics.bearing_y;
2122          advance = metrics.advance;
2123        }
2124      }
2125
2126      /* GWW: Do vertical metrics get loaded incrementally too? */
2127
2128#endif /* FT_CONFIG_OPTION_INCREMENTAL */
2129
2130      glyph->linearVertAdvance = advance;
2131
2132      /* scale the metrics */
2133      if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
2134      {
2135        top     = FT_MulFix( top,     y_scale );
2136        advance = FT_MulFix( advance, y_scale );
2137      }
2138
2139      /* XXX: for now, we have no better algorithm for the lsb, but it */
2140      /*      should work fine.                                        */
2141      /*                                                               */
2142      glyph->metrics.vertBearingX = glyph->metrics.horiBearingX -
2143                                      glyph->metrics.horiAdvance / 2;
2144      glyph->metrics.vertBearingY = top;
2145      glyph->metrics.vertAdvance  = advance;
2146    }
2147
2148    return 0;
2149  }
2150
2151
2152#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
2153
2154  static FT_Error
2155  load_sbit_image( TT_Size       size,
2156                   TT_GlyphSlot  glyph,
2157                   FT_UInt       glyph_index,
2158                   FT_Int32      load_flags )
2159  {
2160    TT_Face             face;
2161    SFNT_Service        sfnt;
2162    FT_Stream           stream;
2163    FT_Error            error;
2164    TT_SBit_MetricsRec  metrics;
2165
2166
2167    face   = (TT_Face)glyph->face;
2168    sfnt   = (SFNT_Service)face->sfnt;
2169    stream = face->root.stream;
2170
2171    error = sfnt->load_sbit_image( face,
2172                                   size->strike_index,
2173                                   glyph_index,
2174                                   (FT_UInt)load_flags,
2175                                   stream,
2176                                   &glyph->bitmap,
2177                                   &metrics );
2178    if ( !error )
2179    {
2180      glyph->outline.n_points   = 0;
2181      glyph->outline.n_contours = 0;
2182
2183      glyph->metrics.width  = (FT_Pos)metrics.width  * 64;
2184      glyph->metrics.height = (FT_Pos)metrics.height * 64;
2185
2186      glyph->metrics.horiBearingX = (FT_Pos)metrics.horiBearingX * 64;
2187      glyph->metrics.horiBearingY = (FT_Pos)metrics.horiBearingY * 64;
2188      glyph->metrics.horiAdvance  = (FT_Pos)metrics.horiAdvance  * 64;
2189
2190      glyph->metrics.vertBearingX = (FT_Pos)metrics.vertBearingX * 64;
2191      glyph->metrics.vertBearingY = (FT_Pos)metrics.vertBearingY * 64;
2192      glyph->metrics.vertAdvance  = (FT_Pos)metrics.vertAdvance  * 64;
2193
2194      glyph->format = FT_GLYPH_FORMAT_BITMAP;
2195
2196      if ( load_flags & FT_LOAD_VERTICAL_LAYOUT )
2197      {
2198        glyph->bitmap_left = metrics.vertBearingX;
2199        glyph->bitmap_top  = metrics.vertBearingY;
2200      }
2201      else
2202      {
2203        glyph->bitmap_left = metrics.horiBearingX;
2204        glyph->bitmap_top  = metrics.horiBearingY;
2205      }
2206    }
2207
2208    return error;
2209  }
2210
2211#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
2212
2213
2214  static FT_Error
2215  tt_loader_init( TT_Loader     loader,
2216                  TT_Size       size,
2217                  TT_GlyphSlot  glyph,
2218                  FT_Int32      load_flags,
2219                  FT_Bool       glyf_table_only )
2220  {
2221    FT_Error  error;
2222
2223    TT_Face    face;
2224    FT_Stream  stream;
2225#ifdef TT_USE_BYTECODE_INTERPRETER
2226    FT_Bool    pedantic = FT_BOOL( load_flags & FT_LOAD_PEDANTIC );
2227#endif
2228
2229
2230    face   = (TT_Face)glyph->face;
2231    stream = face->root.stream;
2232
2233    FT_MEM_ZERO( loader, sizeof ( TT_LoaderRec ) );
2234
2235#ifdef TT_USE_BYTECODE_INTERPRETER
2236
2237    /* load execution context */
2238    if ( IS_HINTED( load_flags ) && !glyf_table_only )
2239    {
2240      TT_ExecContext  exec;
2241      FT_Bool         grayscale;
2242
2243#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
2244      TT_Driver  driver = (TT_Driver)FT_FACE_DRIVER( face );
2245
2246      FT_Bool  subpixel_hinting = FALSE;
2247
2248#if 0
2249      /* not used yet */
2250      FT_Bool  compatible_widths;
2251      FT_Bool  symmetrical_smoothing;
2252      FT_Bool  bgr;
2253      FT_Bool  vertical_lcd;
2254      FT_Bool  subpixel_positioned;
2255      FT_Bool  gray_cleartype;
2256#endif
2257#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
2258
2259      FT_Bool  reexecute = FALSE;
2260
2261
2262      if ( size->bytecode_ready < 0 || size->cvt_ready < 0 )
2263      {
2264        error = tt_size_ready_bytecode( size, pedantic );
2265        if ( error )
2266          return error;
2267      }
2268      else if ( size->bytecode_ready )
2269        return size->bytecode_ready;
2270      else if ( size->cvt_ready )
2271        return size->cvt_ready;
2272
2273      /* query new execution context */
2274      exec = size->context;
2275      if ( !exec )
2276        return FT_THROW( Could_Not_Find_Context );
2277
2278#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
2279
2280      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
2281      {
2282        subpixel_hinting = FT_BOOL( ( FT_LOAD_TARGET_MODE( load_flags ) !=
2283                                      FT_RENDER_MODE_MONO               )  &&
2284                                    SPH_OPTION_SET_SUBPIXEL                );
2285
2286        if ( subpixel_hinting )
2287          grayscale = FALSE;
2288        else if ( SPH_OPTION_SET_GRAYSCALE )
2289        {
2290          grayscale        = TRUE;
2291          subpixel_hinting = FALSE;
2292        }
2293        else
2294          grayscale = FALSE;
2295
2296        if ( FT_IS_TRICKY( glyph->face ) )
2297          subpixel_hinting = FALSE;
2298
2299        exec->ignore_x_mode      = subpixel_hinting || grayscale;
2300        exec->rasterizer_version = SPH_OPTION_SET_RASTERIZER_VERSION;
2301        if ( exec->sph_tweak_flags & SPH_TWEAK_RASTERIZER_35 )
2302          exec->rasterizer_version = TT_INTERPRETER_VERSION_35;
2303
2304#if 1
2305        exec->compatible_widths     = SPH_OPTION_SET_COMPATIBLE_WIDTHS;
2306        exec->symmetrical_smoothing = TRUE;
2307        exec->bgr                   = FALSE;
2308        exec->vertical_lcd          = FALSE;
2309        exec->subpixel_positioned   = TRUE;
2310        exec->gray_cleartype        = FALSE;
2311#else /* 0 */
2312        exec->compatible_widths =
2313          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2314                   TT_LOAD_COMPATIBLE_WIDTHS );
2315        exec->symmetrical_smoothing =
2316          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2317                   TT_LOAD_SYMMETRICAL_SMOOTHING );
2318        exec->bgr =
2319          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2320                   TT_LOAD_BGR );
2321        exec->vertical_lcd =
2322          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2323                   TT_LOAD_VERTICAL_LCD );
2324        exec->subpixel_positioned =
2325          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2326                   TT_LOAD_SUBPIXEL_POSITIONED );
2327        exec->gray_cleartype =
2328          FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2329                   TT_LOAD_GRAY_CLEARTYPE );
2330#endif /* 0 */
2331
2332      }
2333      else
2334
2335#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
2336
2337      {
2338        grayscale = FT_BOOL( FT_LOAD_TARGET_MODE( load_flags ) !=
2339                             FT_RENDER_MODE_MONO );
2340      }
2341
2342      error = TT_Load_Context( exec, face, size );
2343      if ( error )
2344        return error;
2345
2346#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
2347
2348      if ( driver->interpreter_version == TT_INTERPRETER_VERSION_38 )
2349      {
2350        /* a change from mono to subpixel rendering (and vice versa) */
2351        /* requires a re-execution of the CVT program                */
2352        if ( subpixel_hinting != exec->subpixel_hinting )
2353        {
2354          FT_TRACE4(( "tt_loader_init: subpixel hinting change,"
2355                      " re-executing `prep' table\n" ));
2356
2357          exec->subpixel_hinting = subpixel_hinting;
2358          reexecute              = TRUE;
2359        }
2360
2361        /* a change from mono to grayscale rendering (and vice versa) */
2362        /* requires a re-execution of the CVT program                 */
2363        if ( grayscale != exec->grayscale )
2364        {
2365          FT_TRACE4(( "tt_loader_init: grayscale hinting change,"
2366                      " re-executing `prep' table\n" ));
2367
2368          exec->grayscale = grayscale;
2369          reexecute       = TRUE;
2370        }
2371      }
2372      else
2373
2374#endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
2375
2376      {
2377        /* a change from mono to grayscale rendering (and vice versa) */
2378        /* requires a re-execution of the CVT program                 */
2379        if ( grayscale != exec->grayscale )
2380        {
2381          FT_TRACE4(( "tt_loader_init: grayscale hinting change,"
2382                      " re-executing `prep' table\n" ));
2383
2384          exec->grayscale = grayscale;
2385          reexecute       = TRUE;
2386        }
2387      }
2388
2389      if ( reexecute )
2390      {
2391        FT_UInt  i;
2392
2393
2394        for ( i = 0; i < size->cvt_size; i++ )
2395          size->cvt[i] = FT_MulFix( face->cvt[i], size->ttmetrics.scale );
2396        error = tt_size_run_prep( size, pedantic );
2397        if ( error )
2398          return error;
2399      }
2400
2401      /* check whether the cvt program has disabled hinting */
2402      if ( exec->GS.instruct_control & 1 )
2403        load_flags |= FT_LOAD_NO_HINTING;
2404
2405      /* load default graphics state -- if needed */
2406      if ( exec->GS.instruct_control & 2 )
2407        exec->GS = tt_default_graphics_state;
2408
2409#ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
2410      /* check whether we have a font hinted for ClearType --           */
2411      /* note that this flag can also be modified in a glyph's bytecode */
2412      if ( exec->GS.instruct_control & 4 )
2413        exec->ignore_x_mode = 0;
2414#endif
2415
2416      exec->pedantic_hinting = FT_BOOL( load_flags & FT_LOAD_PEDANTIC );
2417      loader->exec = exec;
2418      loader->instructions = exec->glyphIns;
2419    }
2420
2421#endif /* TT_USE_BYTECODE_INTERPRETER */
2422
2423    /* seek to the beginning of the glyph table -- for Type 42 fonts     */
2424    /* the table might be accessed from a Postscript stream or something */
2425    /* else...                                                           */
2426
2427#ifdef FT_CONFIG_OPTION_INCREMENTAL
2428
2429    if ( face->root.internal->incremental_interface )
2430      loader->glyf_offset = 0;
2431    else
2432
2433#endif
2434
2435    {
2436      error = face->goto_table( face, TTAG_glyf, stream, 0 );
2437
2438      if ( FT_ERR_EQ( error, Table_Missing ) )
2439        loader->glyf_offset = 0;
2440      else if ( error )
2441      {
2442        FT_ERROR(( "tt_loader_init: could not access glyph table\n" ));
2443        return error;
2444      }
2445      else
2446        loader->glyf_offset = FT_STREAM_POS();
2447    }
2448
2449    /* get face's glyph loader */
2450    if ( !glyf_table_only )
2451    {
2452      FT_GlyphLoader  gloader = glyph->internal->loader;
2453
2454
2455      FT_GlyphLoader_Rewind( gloader );
2456      loader->gloader = gloader;
2457    }
2458
2459    loader->load_flags = (FT_ULong)load_flags;
2460
2461    loader->face   = face;
2462    loader->size   = size;
2463    loader->glyph  = (FT_GlyphSlot)glyph;
2464    loader->stream = stream;
2465
2466    loader->composites.head = NULL;
2467    loader->composites.tail = NULL;
2468
2469    return FT_Err_Ok;
2470  }
2471
2472
2473  static void
2474  tt_loader_done( TT_Loader  loader )
2475  {
2476    FT_List_Finalize( &loader->composites,
2477                      NULL,
2478                      loader->face->root.memory,
2479                      NULL );
2480  }
2481
2482
2483  /*************************************************************************/
2484  /*                                                                       */
2485  /* <Function>                                                            */
2486  /*    TT_Load_Glyph                                                      */
2487  /*                                                                       */
2488  /* <Description>                                                         */
2489  /*    A function used to load a single glyph within a given glyph slot,  */
2490  /*    for a given size.                                                  */
2491  /*                                                                       */
2492  /* <Input>                                                               */
2493  /*    glyph       :: A handle to a target slot object where the glyph    */
2494  /*                   will be loaded.                                     */
2495  /*                                                                       */
2496  /*    size        :: A handle to the source face size at which the glyph */
2497  /*                   must be scaled/loaded.                              */
2498  /*                                                                       */
2499  /*    glyph_index :: The index of the glyph in the font file.            */
2500  /*                                                                       */
2501  /*    load_flags  :: A flag indicating what to load for this glyph.  The */
2502  /*                   FT_LOAD_XXX constants can be used to control the    */
2503  /*                   glyph loading process (e.g., whether the outline    */
2504  /*                   should be scaled, whether to load bitmaps or not,   */
2505  /*                   whether to hint the outline, etc).                  */
2506  /*                                                                       */
2507  /* <Return>                                                              */
2508  /*    FreeType error code.  0 means success.                             */
2509  /*                                                                       */
2510  FT_LOCAL_DEF( FT_Error )
2511  TT_Load_Glyph( TT_Size       size,
2512                 TT_GlyphSlot  glyph,
2513                 FT_UInt       glyph_index,
2514                 FT_Int32      load_flags )
2515  {
2516    FT_Error      error;
2517    TT_LoaderRec  loader;
2518
2519
2520    FT_TRACE1(( "TT_Load_Glyph: glyph index %d\n", glyph_index ));
2521
2522#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
2523
2524    /* try to load embedded bitmap if any              */
2525    /*                                                 */
2526    /* XXX: The convention should be emphasized in     */
2527    /*      the documents because it can be confusing. */
2528    if ( size->strike_index != 0xFFFFFFFFUL      &&
2529         ( load_flags & FT_LOAD_NO_BITMAP ) == 0 )
2530    {
2531      error = load_sbit_image( size, glyph, glyph_index, load_flags );
2532      if ( !error )
2533      {
2534        if ( FT_IS_SCALABLE( glyph->face ) )
2535        {
2536          /* for the bbox we need the header only */
2537          (void)tt_loader_init( &loader, size, glyph, load_flags, TRUE );
2538          (void)load_truetype_glyph( &loader, glyph_index, 0, TRUE );
2539          tt_loader_done( &loader );
2540          glyph->linearHoriAdvance = loader.linear;
2541          glyph->linearVertAdvance = loader.vadvance;
2542
2543          /* sanity checks: if `xxxAdvance' in the sbit metric */
2544          /* structure isn't set, use `linearXXXAdvance'      */
2545          if ( !glyph->metrics.horiAdvance && glyph->linearHoriAdvance )
2546            glyph->metrics.horiAdvance =
2547              FT_MulFix( glyph->linearHoriAdvance,
2548                         size->root.metrics.x_scale );
2549          if ( !glyph->metrics.vertAdvance && glyph->linearVertAdvance )
2550            glyph->metrics.vertAdvance =
2551              FT_MulFix( glyph->linearVertAdvance,
2552                         size->root.metrics.y_scale );
2553        }
2554
2555        return FT_Err_Ok;
2556      }
2557    }
2558
2559#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
2560
2561    /* if FT_LOAD_NO_SCALE is not set, `ttmetrics' must be valid */
2562    if ( !( load_flags & FT_LOAD_NO_SCALE ) && !size->ttmetrics.valid )
2563      return FT_THROW( Invalid_Size_Handle );
2564
2565    if ( load_flags & FT_LOAD_SBITS_ONLY )
2566      return FT_THROW( Invalid_Argument );
2567
2568    error = tt_loader_init( &loader, size, glyph, load_flags, FALSE );
2569    if ( error )
2570      return error;
2571
2572    glyph->format        = FT_GLYPH_FORMAT_OUTLINE;
2573    glyph->num_subglyphs = 0;
2574    glyph->outline.flags = 0;
2575
2576    /* main loading loop */
2577    error = load_truetype_glyph( &loader, glyph_index, 0, FALSE );
2578    if ( !error )
2579    {
2580      if ( glyph->format == FT_GLYPH_FORMAT_COMPOSITE )
2581      {
2582        glyph->num_subglyphs = loader.gloader->base.num_subglyphs;
2583        glyph->subglyphs     = loader.gloader->base.subglyphs;
2584      }
2585      else
2586      {
2587        glyph->outline        = loader.gloader->base.outline;
2588        glyph->outline.flags &= ~FT_OUTLINE_SINGLE_PASS;
2589
2590        /* Translate array so that (0,0) is the glyph's origin.  Note  */
2591        /* that this behaviour is independent on the value of bit 1 of */
2592        /* the `flags' field in the `head' table -- at least major     */
2593        /* applications like Acroread indicate that.                   */
2594        if ( loader.pp1.x )
2595          FT_Outline_Translate( &glyph->outline, -loader.pp1.x, 0 );
2596      }
2597
2598#ifdef TT_USE_BYTECODE_INTERPRETER
2599
2600      if ( IS_HINTED( load_flags ) )
2601      {
2602        if ( loader.exec->GS.scan_control )
2603        {
2604          /* convert scan conversion mode to FT_OUTLINE_XXX flags */
2605          switch ( loader.exec->GS.scan_type )
2606          {
2607          case 0: /* simple drop-outs including stubs */
2608            glyph->outline.flags |= FT_OUTLINE_INCLUDE_STUBS;
2609            break;
2610          case 1: /* simple drop-outs excluding stubs */
2611            /* nothing; it's the default rendering mode */
2612            break;
2613          case 4: /* smart drop-outs including stubs */
2614            glyph->outline.flags |= FT_OUTLINE_SMART_DROPOUTS |
2615                                    FT_OUTLINE_INCLUDE_STUBS;
2616            break;
2617          case 5: /* smart drop-outs excluding stubs  */
2618            glyph->outline.flags |= FT_OUTLINE_SMART_DROPOUTS;
2619            break;
2620
2621          default: /* no drop-out control */
2622            glyph->outline.flags |= FT_OUTLINE_IGNORE_DROPOUTS;
2623            break;
2624          }
2625        }
2626        else
2627          glyph->outline.flags |= FT_OUTLINE_IGNORE_DROPOUTS;
2628      }
2629
2630#endif /* TT_USE_BYTECODE_INTERPRETER */
2631
2632      error = compute_glyph_metrics( &loader, glyph_index );
2633    }
2634
2635    tt_loader_done( &loader );
2636
2637    /* Set the `high precision' bit flag.                           */
2638    /* This is _critical_ to get correct output for monochrome      */
2639    /* TrueType glyphs at all sizes using the bytecode interpreter. */
2640    /*                                                              */
2641    if ( !( load_flags & FT_LOAD_NO_SCALE ) &&
2642         size->root.metrics.y_ppem < 24     )
2643      glyph->outline.flags |= FT_OUTLINE_HIGH_PRECISION;
2644
2645    return error;
2646  }
2647
2648
2649/* END */
2650