ttgload.c revision 318f3befc67e026037da33fb7b5b9a22d567df9a
1/***************************************************************************/
2/*                                                                         */
3/*  ttgload.c                                                              */
4/*                                                                         */
5/*    TrueType Glyph Loader (body).                                        */
6/*                                                                         */
7/*  Copyright 1996-2001, 2002 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
27#include "ttgload.h"
28
29#include "tterrors.h"
30
31
32  /*************************************************************************/
33  /*                                                                       */
34  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
35  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
36  /* messages during execution.                                            */
37  /*                                                                       */
38#undef  FT_COMPONENT
39#define FT_COMPONENT  trace_ttgload
40
41
42  /*************************************************************************/
43  /*                                                                       */
44  /* Composite font flags.                                                 */
45  /*                                                                       */
46#define ARGS_ARE_WORDS       0x001
47#define ARGS_ARE_XY_VALUES   0x002
48#define ROUND_XY_TO_GRID     0x004
49#define WE_HAVE_A_SCALE      0x008
50/* reserved                  0x010 */
51#define MORE_COMPONENTS      0x020
52#define WE_HAVE_AN_XY_SCALE  0x040
53#define WE_HAVE_A_2X2        0x080
54#define WE_HAVE_INSTR        0x100
55#define USE_MY_METRICS       0x200
56
57
58
59  /*************************************************************************/
60  /*                                                                       */
61  /* <Function>                                                            */
62  /*    TT_Get_Metrics                                                     */
63  /*                                                                       */
64  /* <Description>                                                         */
65  /*    Returns the horizontal or vertical metrics in font units for a     */
66  /*    given glyph.  The metrics are the left side bearing (resp. top     */
67  /*    side bearing) and advance width (resp. advance height).            */
68  /*                                                                       */
69  /* <Input>                                                               */
70  /*    header  :: A pointer to either the horizontal or vertical metrics  */
71  /*               structure.                                              */
72  /*                                                                       */
73  /*    idx     :: The glyph index.                                        */
74  /*                                                                       */
75  /* <Output>                                                              */
76  /*    bearing :: The bearing, either left side or top side.              */
77  /*                                                                       */
78  /*    advance :: The advance width resp. advance height.                 */
79  /*                                                                       */
80  /* <Note>                                                                */
81  /*    This function will much probably move to another component in the  */
82  /*    near future, but I haven't decided which yet.                      */
83  /*                                                                       */
84  FT_LOCAL_DEF( void )
85  TT_Get_Metrics( TT_HoriHeader*  header,
86                  FT_UInt         idx,
87                  FT_Short*       bearing,
88                  FT_UShort*      advance )
89  {
90    TT_LongMetrics  longs_m;
91    FT_UShort       k = header->number_Of_HMetrics;
92
93
94    if ( idx < (FT_UInt)k )
95    {
96      longs_m  = (TT_LongMetrics )header->long_metrics + idx;
97      *bearing = longs_m->bearing;
98      *advance = longs_m->advance;
99    }
100    else
101    {
102      *bearing = ((TT_ShortMetrics*)header->short_metrics)[idx - k];
103      *advance = ((TT_LongMetrics )header->long_metrics)[k - 1].advance;
104    }
105  }
106
107
108  /*************************************************************************/
109  /*                                                                       */
110  /* Returns the horizontal metrics in font units for a given glyph.  If   */
111  /* `check' is true, take care of monospaced fonts by returning the       */
112  /* advance width maximum.                                                */
113  /*                                                                       */
114  static void
115  Get_HMetrics( TT_Face     face,
116                FT_UInt     idx,
117                FT_Bool     check,
118                FT_Short*   lsb,
119                FT_UShort*  aw )
120  {
121    TT_Get_Metrics( &face->horizontal, idx, lsb, aw );
122
123    if ( check && face->postscript.isFixedPitch )
124      *aw = face->horizontal.advance_Width_Max;
125  }
126
127
128  /*************************************************************************/
129  /*                                                                       */
130  /* Returns the advance width table for a given pixel size if it is found */
131  /* in the font's `hdmx' table (if any).                                  */
132  /*                                                                       */
133  static FT_Byte*
134  Get_Advance_Widths( TT_Face    face,
135                      FT_UShort  ppem )
136  {
137    FT_UShort  n;
138
139
140    for ( n = 0; n < face->hdmx.num_records; n++ )
141      if ( face->hdmx.records[n].ppem == ppem )
142        return face->hdmx.records[n].widths;
143
144    return NULL;
145  }
146
147
148#define cur_to_org( n, zone ) \
149          FT_MEM_COPY( (zone)->org, (zone)->cur, (n) * sizeof ( FT_Vector ) )
150
151#define org_to_cur( n, zone ) \
152          FT_MEM_COPY( (zone)->cur, (zone)->org, (n) * sizeof ( FT_Vector ) )
153
154
155  /*************************************************************************/
156  /*                                                                       */
157  /* Translates an array of coordinates.                                   */
158  /*                                                                       */
159  static void
160  translate_array( FT_UInt     n,
161                   FT_Vector*  coords,
162                   FT_Pos      delta_x,
163                   FT_Pos      delta_y )
164  {
165    FT_UInt  k;
166
167
168    if ( delta_x )
169      for ( k = 0; k < n; k++ )
170        coords[k].x += delta_x;
171
172    if ( delta_y )
173      for ( k = 0; k < n; k++ )
174        coords[k].y += delta_y;
175  }
176
177
178  static void
179  tt_prepare_zone( TT_GlyphZone  zone,
180                   FT_GlyphLoad  load,
181                   FT_UInt       start_point,
182                   FT_UInt       start_contour )
183  {
184    zone->n_points   = (FT_UShort)( load->outline.n_points - start_point );
185    zone->n_contours = (FT_Short) ( load->outline.n_contours - start_contour );
186    zone->org        = load->extra_points + start_point;
187    zone->cur        = load->outline.points + start_point;
188    zone->tags       = (FT_Byte*)load->outline.tags + start_point;
189    zone->contours   = (FT_UShort*)load->outline.contours + start_contour;
190  }
191
192
193#undef  IS_HINTED
194#define IS_HINTED( flags )  ( ( flags & FT_LOAD_NO_HINTING ) == 0 )
195
196
197  /*************************************************************************/
198  /*                                                                       */
199  /* The following functions are used by default with TrueType fonts.      */
200  /* However, they can be replaced by alternatives if we need to support   */
201  /* TrueType-compressed formats (like MicroType) in the future.           */
202  /*                                                                       */
203  /*************************************************************************/
204
205  FT_CALLBACK_DEF( FT_Error )
206  TT_Access_Glyph_Frame( TT_Loader  loader,
207                         FT_UInt    glyph_index,
208                         FT_ULong   offset,
209                         FT_UInt    byte_count )
210  {
211    FT_Error   error;
212    FT_Stream  stream = loader->stream;
213
214    /* for non-debug mode */
215    FT_UNUSED( glyph_index );
216
217
218    FT_TRACE5(( "Glyph %ld\n", glyph_index ));
219
220    /* the following line sets the `error' variable through macros! */
221    if ( FT_STREAM_SEEK( offset ) || FT_FRAME_ENTER( byte_count ) )
222      return error;
223
224    return TT_Err_Ok;
225  }
226
227
228  FT_CALLBACK_DEF( void )
229  TT_Forget_Glyph_Frame( TT_Loader  loader )
230  {
231    FT_Stream  stream = loader->stream;
232
233
234    FT_FRAME_EXIT();
235  }
236
237
238  FT_CALLBACK_DEF( FT_Error )
239  TT_Load_Glyph_Header( TT_Loader  loader )
240  {
241    FT_Stream  stream   = loader->stream;
242    FT_Int     byte_len = loader->byte_len - 10;
243
244
245    if ( byte_len < 0 )
246      return TT_Err_Invalid_Outline;
247
248    loader->n_contours = FT_GET_SHORT();
249
250    loader->bbox.xMin = FT_GET_SHORT();
251    loader->bbox.yMin = FT_GET_SHORT();
252    loader->bbox.xMax = FT_GET_SHORT();
253    loader->bbox.yMax = FT_GET_SHORT();
254
255    FT_TRACE5(( "  # of contours: %d\n", loader->n_contours ));
256    FT_TRACE5(( "  xMin: %4d  xMax: %4d\n", loader->bbox.xMin,
257                                            loader->bbox.xMax ));
258    FT_TRACE5(( "  yMin: %4d  yMax: %4d\n", loader->bbox.yMin,
259                                            loader->bbox.yMax ));
260    loader->byte_len = byte_len;
261
262    return TT_Err_Ok;
263  }
264
265
266  FT_CALLBACK_DEF( FT_Error )
267  TT_Load_Simple_Glyph( TT_Loader  load )
268  {
269    FT_Error        error;
270    FT_Stream       stream     = load->stream;
271    FT_GlyphLoader  gloader    = load->gloader;
272    FT_Int          n_contours = load->n_contours;
273    FT_Outline*     outline;
274    TT_Face         face       = (TT_Face)load->face;
275    TT_GlyphSlot    slot       = (TT_GlyphSlot)load->glyph;
276    FT_UShort       n_ins;
277    FT_Int          n, n_points;
278    FT_Int          byte_len   = load->byte_len;
279
280
281    /* reading the contours endpoints & number of points */
282    {
283      short*  cur   = gloader->current.outline.contours;
284      short*  limit = cur + n_contours;
285
286
287      /* check space for contours array + instructions count */
288      byte_len -= 2 * ( n_contours + 1 );
289      if ( byte_len < 0 )
290        goto Invalid_Outline;
291
292      for ( ; cur < limit; cur++ )
293        cur[0] = FT_GET_USHORT();
294
295      n_points = 0;
296      if ( n_contours > 0 )
297        n_points = cur[-1] + 1;
298
299      error = FT_GlyphLoader_CheckPoints( gloader, n_points + 2, 0 );
300      if ( error )
301        goto Fail;
302
303      /* we'd better check the contours table right now */
304      outline = &gloader->current.outline;
305
306      for ( cur = outline->contours + 1; cur < limit; cur++ )
307        if ( cur[-1] >= cur[0] )
308          goto Invalid_Outline;
309    }
310
311    /* reading the bytecode instructions */
312    slot->control_len  = 0;
313    slot->control_data = 0;
314
315    n_ins = FT_GET_USHORT();
316
317    FT_TRACE5(( "  Instructions size: %d\n", n_ins ));
318
319    if ( n_ins > face->max_profile.maxSizeOfInstructions )
320    {
321      FT_TRACE0(( "TT_Load_Simple_Glyph: Too many instructions!\n" ));
322      error = TT_Err_Too_Many_Hints;
323      goto Fail;
324    }
325
326    byte_len -= n_ins;
327    if ( byte_len < 0 )
328    {
329      FT_TRACE0(( "TT_Load_Simple_Glyph: Instruction count mismatch!\n" ));
330      error = TT_Err_Too_Many_Hints;
331      goto Fail;
332    }
333
334#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
335
336    if ( ( load->load_flags                        &
337         ( FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING ) ) == 0 &&
338           load->instructions )
339    {
340      slot->control_len  = n_ins;
341      slot->control_data = load->instructions;
342
343      FT_MEM_COPY( load->instructions, stream->cursor, n_ins );
344    }
345
346#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
347
348    stream->cursor += n_ins;
349
350    /* reading the point tags */
351    {
352      FT_Byte*  flag  = (FT_Byte*)outline->tags;
353      FT_Byte*  limit = flag + n_points;
354      FT_Byte   c, count;
355
356
357      while ( flag < limit )
358      {
359        if ( --byte_len < 0 )
360          goto Invalid_Outline;
361
362        *flag++ = c = FT_GET_BYTE();
363        if ( c & 8 )
364        {
365          if ( --byte_len < 0 )
366            goto Invalid_Outline;
367
368          count = FT_GET_BYTE();
369          if ( flag + count > limit )
370            goto Invalid_Outline;
371
372          for ( ; count > 0; count-- )
373            *flag++ = c;
374        }
375      }
376
377      /* check that there is enough room to load the coordinates */
378      for ( flag = (FT_Byte*)outline->tags; flag < limit; flag++ )
379      {
380        if ( *flag & 2 )
381          byte_len -= 1;
382        else if ( ( *flag & 16 ) == 0 )
383          byte_len -= 2;
384
385        if ( *flag & 4 )
386          byte_len -= 1;
387        else if ( ( *flag & 32 ) == 0 )
388          byte_len -= 2;
389      }
390
391      if ( byte_len < 0 )
392        goto Invalid_Outline;
393    }
394
395    /* reading the X coordinates */
396
397    {
398      FT_Vector*  vec   = outline->points;
399      FT_Vector*  limit = vec + n_points;
400      FT_Byte*    flag  = (FT_Byte*)outline->tags;
401      FT_Pos      x     = 0;
402
403
404      for ( ; vec < limit; vec++, flag++ )
405      {
406        FT_Pos  y = 0;
407
408
409        if ( *flag & 2 )
410        {
411          y = FT_GET_BYTE();
412          if ( ( *flag & 16 ) == 0 )
413            y = -y;
414        }
415        else if ( ( *flag & 16 ) == 0 )
416          y = FT_GET_SHORT();
417
418        x     += y;
419        vec->x = x;
420      }
421    }
422
423    /* reading the Y coordinates */
424
425    {
426      FT_Vector*  vec   = gloader->current.outline.points;
427      FT_Vector*  limit = vec + n_points;
428      FT_Byte*    flag  = (FT_Byte*)outline->tags;
429      FT_Pos      x     = 0;
430
431
432      for ( ; vec < limit; vec++, flag++ )
433      {
434        FT_Pos  y = 0;
435
436
437        if ( *flag & 4 )
438        {
439          y = FT_GET_BYTE();
440          if ( ( *flag & 32 ) == 0 )
441            y = -y;
442        }
443        else if ( ( *flag & 32 ) == 0 )
444          y = FT_GET_SHORT();
445
446        x     += y;
447        vec->y = x;
448      }
449    }
450
451    /* clear the touch tags */
452    for ( n = 0; n < n_points; n++ )
453      outline->tags[n] &= FT_Curve_Tag_On;
454
455    outline->n_points   = (FT_UShort)n_points;
456    outline->n_contours = (FT_Short) n_contours;
457
458    load->byte_len = byte_len;
459
460  Fail:
461    return error;
462
463  Invalid_Outline:
464    error = TT_Err_Invalid_Outline;
465    goto Fail;
466  }
467
468
469  FT_CALLBACK_DEF( FT_Error )
470  TT_Load_Composite_Glyph( TT_Loader  loader )
471  {
472    FT_Error        error;
473    FT_Stream       stream  = loader->stream;
474    FT_GlyphLoader  gloader = loader->gloader;
475    FT_SubGlyph     subglyph;
476    FT_UInt         num_subglyphs;
477    FT_Int          byte_len = loader->byte_len;
478
479
480    num_subglyphs = 0;
481
482    do
483    {
484      FT_Fixed  xx, xy, yy, yx;
485
486
487      /* check that we can load a new subglyph */
488      error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs + 1 );
489      if ( error )
490        goto Fail;
491
492      /* check space */
493      byte_len -= 4;
494      if ( byte_len < 0 )
495        goto Invalid_Composite;
496
497      subglyph = gloader->current.subglyphs + num_subglyphs;
498
499      subglyph->arg1 = subglyph->arg2 = 0;
500
501      subglyph->flags = FT_GET_USHORT();
502      subglyph->index = FT_GET_USHORT();
503
504      /* check space */
505      byte_len -= 2;
506      if ( subglyph->flags & ARGS_ARE_WORDS )
507        byte_len -= 2;
508      if ( subglyph->flags & WE_HAVE_A_SCALE )
509        byte_len -= 2;
510      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
511        byte_len -= 4;
512      else if ( subglyph->flags & WE_HAVE_A_2X2 )
513        byte_len -= 8;
514
515      if ( byte_len < 0 )
516        goto Invalid_Composite;
517
518      /* read arguments */
519      if ( subglyph->flags & ARGS_ARE_WORDS )
520      {
521        subglyph->arg1 = FT_GET_SHORT();
522        subglyph->arg2 = FT_GET_SHORT();
523      }
524      else
525      {
526        subglyph->arg1 = FT_GET_CHAR();
527        subglyph->arg2 = FT_GET_CHAR();
528      }
529
530      /* read transform */
531      xx = yy = 0x10000L;
532      xy = yx = 0;
533
534      if ( subglyph->flags & WE_HAVE_A_SCALE )
535      {
536        xx = (FT_Fixed)FT_GET_SHORT() << 2;
537        yy = xx;
538      }
539      else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE )
540      {
541        xx = (FT_Fixed)FT_GET_SHORT() << 2;
542        yy = (FT_Fixed)FT_GET_SHORT() << 2;
543      }
544      else if ( subglyph->flags & WE_HAVE_A_2X2 )
545      {
546        xx = (FT_Fixed)FT_GET_SHORT() << 2;
547        yx = (FT_Fixed)FT_GET_SHORT() << 2;
548        xy = (FT_Fixed)FT_GET_SHORT() << 2;
549        yy = (FT_Fixed)FT_GET_SHORT() << 2;
550      }
551
552      subglyph->transform.xx = xx;
553      subglyph->transform.xy = xy;
554      subglyph->transform.yx = yx;
555      subglyph->transform.yy = yy;
556
557      num_subglyphs++;
558
559    } while ( subglyph->flags & MORE_COMPONENTS );
560
561    gloader->current.num_subglyphs = num_subglyphs;
562
563#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
564    {
565      /* we must undo the FT_FRAME_ENTER in order to point to the */
566      /* composite instructions, if we find some.               */
567      /* we will process them later...                          */
568      /*                                                        */
569      loader->ins_pos = (FT_ULong)( FT_STREAM_POS() +
570                                    stream->cursor - stream->limit );
571    }
572#endif
573
574    loader->byte_len = byte_len;
575
576  Fail:
577    return error;
578
579  Invalid_Composite:
580    error = TT_Err_Invalid_Composite;
581    goto Fail;
582  }
583
584
585  FT_LOCAL_DEF( void )
586  TT_Init_Glyph_Loading( TT_Face  face )
587  {
588    face->access_glyph_frame   = TT_Access_Glyph_Frame;
589    face->read_glyph_header    = TT_Load_Glyph_Header;
590    face->read_simple_glyph    = TT_Load_Simple_Glyph;
591    face->read_composite_glyph = TT_Load_Composite_Glyph;
592    face->forget_glyph_frame   = TT_Forget_Glyph_Frame;
593  }
594
595
596  /*************************************************************************/
597  /*                                                                       */
598  /* <Function>                                                            */
599  /*    TT_Process_Simple_Glyph                                            */
600  /*                                                                       */
601  /* <Description>                                                         */
602  /*    Once a simple glyph has been loaded, it needs to be processed.     */
603  /*    Usually, this means scaling and hinting through bytecode           */
604  /*    interpretation.                                                    */
605  /*                                                                       */
606  static FT_Error
607  TT_Process_Simple_Glyph( TT_Loader  load,
608                           FT_Bool    debug )
609  {
610    FT_GlyphLoader  gloader  = load->gloader;
611    FT_Outline*     outline  = &gloader->current.outline;
612    FT_UInt         n_points = outline->n_points;
613#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
614    FT_UInt         n_ins;
615#endif
616    TT_GlyphZone    zone     = &load->zone;
617    FT_Error        error    = TT_Err_Ok;
618
619    FT_UNUSED( debug );  /* used by truetype interpreter only */
620
621
622#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
623    n_ins = load->glyph->control_len;
624#endif
625
626    /* add shadow points */
627
628    /* Now add the two shadow points at n and n + 1.    */
629    /* We need the left side bearing and advance width. */
630
631    {
632      FT_Vector*  pp1;
633      FT_Vector*  pp2;
634
635
636      /* pp1 = xMin - lsb */
637      pp1    = outline->points + n_points;
638      pp1->x = load->bbox.xMin - load->left_bearing;
639      pp1->y = 0;
640
641      /* pp2 = pp1 + aw */
642      pp2    = pp1 + 1;
643      pp2->x = pp1->x + load->advance;
644      pp2->y = 0;
645
646      outline->tags[n_points    ] = 0;
647      outline->tags[n_points + 1] = 0;
648    }
649
650    /* Note that we return two more points that are not */
651    /* part of the glyph outline.                       */
652
653    n_points += 2;
654
655    /* set up zone for hinting */
656    tt_prepare_zone( zone, &gloader->current, 0, 0 );
657
658    /* eventually scale the glyph */
659    if ( !( load->load_flags & FT_LOAD_NO_SCALE ) )
660    {
661      FT_Vector*  vec     = zone->cur;
662      FT_Vector*  limit   = vec + n_points;
663      FT_Fixed    x_scale = load->size->metrics.x_scale;
664      FT_Fixed    y_scale = load->size->metrics.y_scale;
665
666
667      /* first scale the glyph points */
668      for ( ; vec < limit; vec++ )
669      {
670        vec->x = FT_MulFix( vec->x, x_scale );
671        vec->y = FT_MulFix( vec->y, y_scale );
672      }
673    }
674
675    cur_to_org( n_points, zone );
676
677    /* eventually hint the glyph */
678    if ( IS_HINTED( load->load_flags ) )
679    {
680      FT_Pos  x = zone->org[n_points-2].x;
681
682
683      x = ( ( x + 32 ) & -64 ) - x;
684      translate_array( n_points, zone->org, x, 0 );
685
686      org_to_cur( n_points, zone );
687
688      zone->cur[n_points - 1].x = ( zone->cur[n_points - 1].x + 32 ) & -64;
689
690#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
691
692      /* now consider hinting */
693      if ( n_ins > 0 )
694      {
695        error = TT_Set_CodeRange( load->exec, tt_coderange_glyph,
696                                  load->exec->glyphIns, n_ins );
697        if ( error )
698          goto Exit;
699
700        load->exec->is_composite     = FALSE;
701        load->exec->pedantic_hinting = (FT_Bool)( load->load_flags &
702                                                  FT_LOAD_PEDANTIC );
703        load->exec->pts              = *zone;
704        load->exec->pts.n_points    += 2;
705
706        error = TT_Run_Context( load->exec, debug );
707        if ( error && load->exec->pedantic_hinting )
708          goto Exit;
709
710        error = TT_Err_Ok;  /* ignore bytecode errors in non-pedantic mode */
711      }
712
713#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
714
715    }
716
717    /* save glyph phantom points */
718    if ( !load->preserve_pps )
719    {
720      load->pp1 = zone->cur[n_points - 2];
721      load->pp2 = zone->cur[n_points - 1];
722    }
723
724#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
725  Exit:
726#endif
727    return error;
728  }
729
730
731  /*************************************************************************/
732  /*                                                                       */
733  /* <Function>                                                            */
734  /*    load_truetype_glyph                                                */
735  /*                                                                       */
736  /* <Description>                                                         */
737  /*    Loads a given truetype glyph.  Handles composites and uses a       */
738  /*    TT_Loader object.                                                  */
739  /*                                                                       */
740  static FT_Error
741  load_truetype_glyph( TT_Loader  loader,
742                       FT_UInt    glyph_index )
743  {
744
745#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
746    FT_Stream       stream = loader->stream;
747#endif
748
749    FT_Error        error;
750    TT_Face         face   = (TT_Face)loader->face;
751    FT_ULong        offset;
752    FT_Int          contours_count;
753    FT_UInt         idx, num_points, count;
754    FT_Fixed        x_scale, y_scale;
755    FT_GlyphLoader  gloader = loader->gloader;
756    FT_Bool         opened_frame = 0;
757
758
759    /* check glyph index */
760    idx = glyph_index;
761    if ( idx >= (FT_UInt)face->root.num_glyphs )
762    {
763      error = TT_Err_Invalid_Glyph_Index;
764      goto Exit;
765    }
766
767    loader->glyph_index = glyph_index;
768    num_points          = 0;
769
770    x_scale = 0x10000L;
771    y_scale = 0x10000L;
772    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
773    {
774      x_scale = loader->size->metrics.x_scale;
775      y_scale = loader->size->metrics.y_scale;
776    }
777
778    /* get horizontal metrics */
779    {
780      FT_Short   left_bearing;
781      FT_UShort  advance_width;
782
783
784      Get_HMetrics( face, idx,
785                    (FT_Bool)!( loader->load_flags &
786                                FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ),
787                    &left_bearing,
788                    &advance_width );
789
790      loader->left_bearing = left_bearing;
791      loader->advance      = advance_width;
792
793      if ( !loader->linear_def )
794      {
795        loader->linear_def = 1;
796        loader->linear     = advance_width;
797      }
798    }
799
800    offset = face->glyph_locations[idx];
801    count  = 0;
802
803    if ( idx < (FT_UInt)face->num_locations - 1 )
804       count = face->glyph_locations[idx + 1] - offset;
805
806    if ( count == 0 )
807    {
808      /* as described by Frederic Loyer, these are spaces, and */
809      /* not the unknown glyph.                                */
810      loader->bbox.xMin = 0;
811      loader->bbox.xMax = 0;
812      loader->bbox.yMin = 0;
813      loader->bbox.yMax = 0;
814
815      loader->pp1.x = 0;
816      loader->pp2.x = loader->advance;
817
818      if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
819        loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
820
821#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
822
823      if ( loader->exec )
824        loader->exec->glyphSize = 0;
825
826#endif
827
828      error = TT_Err_Ok;
829      goto Exit;
830    }
831
832    loader->byte_len = (FT_Int)count;
833
834    offset = loader->glyf_offset + offset;
835
836    /* access glyph frame */
837    error = face->access_glyph_frame( loader, glyph_index, offset, count );
838    if ( error )
839      goto Exit;
840
841    opened_frame = 1;
842
843    /* read first glyph header */
844    error = face->read_glyph_header( loader );
845    if ( error )
846      goto Fail;
847
848    contours_count = loader->n_contours;
849
850    count -= 10;
851
852    loader->pp1.x = loader->bbox.xMin - loader->left_bearing;
853    loader->pp1.y = 0;
854    loader->pp2.x = loader->pp1.x + loader->advance;
855    loader->pp2.y = 0;
856
857    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
858    {
859      loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
860      loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
861    }
862
863    /***********************************************************************/
864    /***********************************************************************/
865    /***********************************************************************/
866
867    /* if it is a simple glyph, load it */
868
869    if ( contours_count >= 0 )
870    {
871      /* check that we can add the contours to the glyph */
872      error = FT_GlyphLoader_CheckPoints( gloader, 0, contours_count );
873      if ( error )
874        goto Fail;
875
876      error = face->read_simple_glyph( loader );
877      if ( error )
878        goto Fail;
879
880#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
881
882      {
883        TT_Size  size = (TT_Size)loader->size;
884
885
886        error = TT_Process_Simple_Glyph( loader,
887                                         (FT_Bool)( size && size->debug ) );
888      }
889
890#else
891
892      error = TT_Process_Simple_Glyph( loader, 0 );
893
894#endif
895
896      if ( error )
897        goto Fail;
898
899      FT_GlyphLoader_Add( gloader );
900
901      /* Note: We could have put the simple loader source there */
902      /*       but the code is fat enough already :-)           */
903    }
904
905    /***********************************************************************/
906    /***********************************************************************/
907    /***********************************************************************/
908
909    /* otherwise, load a composite! */
910    else
911    {
912      TT_GlyphSlot  glyph = (TT_GlyphSlot)loader->glyph;
913      FT_UInt       start_point;
914#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
915      FT_UInt       start_contour;
916      FT_ULong      ins_pos;  /* position of composite instructions, if any */
917#endif
918
919
920      /* for each subglyph, read composite header */
921      start_point   = gloader->base.outline.n_points;
922#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
923      start_contour = gloader->base.outline.n_contours;
924#endif
925
926      error = face->read_composite_glyph( loader );
927      if ( error )
928        goto Fail;
929
930#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
931      ins_pos = loader->ins_pos;
932#endif
933      face->forget_glyph_frame( loader );
934      opened_frame = 0;
935
936      /* if the flag FT_LOAD_NO_RECURSE is set, we return the subglyph */
937      /* `as is' in the glyph slot (the client application will be     */
938      /* responsible for interpreting this data)...                    */
939      /*                                                               */
940      if ( loader->load_flags & FT_LOAD_NO_RECURSE )
941      {
942        /* set up remaining glyph fields */
943        FT_GlyphLoader_Add( gloader );
944
945        glyph->num_subglyphs = gloader->base.num_subglyphs;
946        glyph->format        = ft_glyph_format_composite;
947        glyph->subglyphs     = gloader->base.subglyphs;
948
949        goto Exit;
950      }
951
952      /*********************************************************************/
953      /*********************************************************************/
954      /*********************************************************************/
955
956      /* Now, read each subglyph independently. */
957      {
958        FT_Int       n, num_base_points, num_new_points;
959        FT_SubGlyph  subglyph       = 0;
960
961        FT_UInt      num_subglyphs  = gloader->current.num_subglyphs;
962        FT_UInt      num_base_subgs = gloader->base.num_subglyphs;
963
964
965        FT_GlyphLoader_Add( gloader );
966
967        for ( n = 0; n < (FT_Int)num_subglyphs; n++ )
968        {
969          FT_Vector  pp1, pp2;
970          FT_Pos     x, y;
971
972
973          /* Each time we call load_truetype_glyph in this loop, the   */
974          /* value of `gloader.base.subglyphs' can change due to table */
975          /* reallocations.  We thus need to recompute the subglyph    */
976          /* pointer on each iteration.                                */
977          subglyph = gloader->base.subglyphs + num_base_subgs + n;
978
979          pp1 = loader->pp1;
980          pp2 = loader->pp2;
981
982          num_base_points = gloader->base.outline.n_points;
983
984          error = load_truetype_glyph( loader, subglyph->index );
985          if ( error )
986            goto Fail;
987
988          /* restore subglyph pointer */
989          subglyph = gloader->base.subglyphs + num_base_subgs + n;
990
991          if ( subglyph->flags & USE_MY_METRICS )
992          {
993            pp1 = loader->pp1;
994            pp2 = loader->pp2;
995          }
996          else
997          {
998            loader->pp1 = pp1;
999            loader->pp2 = pp2;
1000          }
1001
1002          num_points = gloader->base.outline.n_points;
1003
1004          num_new_points = num_points - num_base_points;
1005
1006          /* now perform the transform required for this subglyph */
1007
1008          if ( subglyph->flags & ( WE_HAVE_A_SCALE     |
1009                                   WE_HAVE_AN_XY_SCALE |
1010                                   WE_HAVE_A_2X2       ) )
1011          {
1012            FT_Vector*  cur   = gloader->base.outline.points +
1013                                  num_base_points;
1014            FT_Vector*  org   = gloader->base.extra_points +
1015                                  num_base_points;
1016            FT_Vector*  limit = cur + num_new_points;
1017
1018
1019            for ( ; cur < limit; cur++, org++ )
1020            {
1021              FT_Vector_Transform( cur, &subglyph->transform );
1022              FT_Vector_Transform( org, &subglyph->transform );
1023            }
1024          }
1025
1026          /* apply offset */
1027
1028          if ( !( subglyph->flags & ARGS_ARE_XY_VALUES ) )
1029          {
1030            FT_UInt     k = subglyph->arg1;
1031            FT_UInt     l = subglyph->arg2;
1032            FT_Vector*  p1;
1033            FT_Vector*  p2;
1034
1035
1036            if ( start_point + k >= (FT_UInt)num_base_points ||
1037                               l >= (FT_UInt)num_new_points  )
1038            {
1039              error = TT_Err_Invalid_Composite;
1040              goto Fail;
1041            }
1042
1043            l += num_base_points;
1044
1045            p1 = gloader->base.outline.points + start_point + k;
1046            p2 = gloader->base.outline.points + start_point + l;
1047
1048            x = p1->x - p2->x;
1049            y = p1->y - p2->y;
1050          }
1051          else
1052          {
1053            x = subglyph->arg1;
1054            y = subglyph->arg2;
1055
1056            if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
1057            {
1058              x = FT_MulFix( x, x_scale );
1059              y = FT_MulFix( y, y_scale );
1060
1061              if ( subglyph->flags & ROUND_XY_TO_GRID )
1062              {
1063                x = ( x + 32 ) & -64;
1064                y = ( y + 32 ) & -64;
1065              }
1066            }
1067          }
1068
1069          if ( x || y )
1070          {
1071            translate_array( num_new_points,
1072                             gloader->base.outline.points + num_base_points,
1073                             x, y );
1074
1075            translate_array( num_new_points,
1076                             gloader->base.extra_points + num_base_points,
1077                             x, y );
1078          }
1079        }
1080
1081        /*******************************************************************/
1082        /*******************************************************************/
1083        /*******************************************************************/
1084
1085        /* we have finished loading all sub-glyphs; now, look for */
1086        /* instructions for this composite!                       */
1087
1088#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
1089
1090        if ( num_subglyphs > 0               &&
1091             loader->exec                    &&
1092             ins_pos > 0                     &&
1093             subglyph->flags & WE_HAVE_INSTR )
1094        {
1095          FT_UShort       n_ins;
1096          TT_ExecContext  exec = loader->exec;
1097          TT_GlyphZone    pts;
1098          FT_Vector*      pp1;
1099
1100
1101          /* read size of instructions */
1102          if ( FT_STREAM_SEEK( ins_pos ) ||
1103               FT_READ_USHORT( n_ins ) )
1104            goto Fail;
1105          FT_TRACE5(( "  Instructions size = %d\n", n_ins ));
1106
1107          /* in some fonts? */
1108          if ( n_ins == 0xFFFFU )
1109            n_ins = 0;
1110
1111          /* check it */
1112          if ( n_ins > face->max_profile.maxSizeOfInstructions )
1113          {
1114            FT_TRACE0(( "Too many instructions (%d) in composite glyph %ld\n",
1115                        n_ins, subglyph->index ));
1116            error = TT_Err_Too_Many_Hints;
1117            goto Fail;
1118          }
1119
1120          /* read the instructions */
1121          if ( FT_STREAM_READ( exec->glyphIns, n_ins ) )
1122            goto Fail;
1123
1124          glyph->control_data = exec->glyphIns;
1125          glyph->control_len  = n_ins;
1126
1127          error = TT_Set_CodeRange( exec,
1128                                    tt_coderange_glyph,
1129                                    exec->glyphIns,
1130                                    n_ins );
1131          if ( error )
1132            goto Fail;
1133
1134          /* prepare the execution context */
1135          tt_prepare_zone( &exec->pts, &gloader->base,
1136                           start_point, start_contour );
1137          pts = &exec->pts;
1138
1139          pts->n_points   = (short)(num_points + 2);
1140          pts->n_contours = gloader->base.outline.n_contours;
1141
1142          /* add phantom points */
1143          pp1    = pts->cur + num_points;
1144          pp1[0] = loader->pp1;
1145          pp1[1] = loader->pp2;
1146
1147          pts->tags[num_points    ] = 0;
1148          pts->tags[num_points + 1] = 0;
1149
1150          /* if hinting, round the phantom points */
1151          if ( IS_HINTED( loader->load_flags ) )
1152          {
1153            pp1[0].x = ( ( loader->pp1.x + 32 ) & -64 );
1154            pp1[1].x = ( ( loader->pp2.x + 32 ) & -64 );
1155          }
1156
1157          {
1158            FT_UInt  k;
1159
1160
1161            for ( k = 0; k < num_points; k++ )
1162              pts->tags[k] &= FT_Curve_Tag_On;
1163          }
1164
1165          cur_to_org( num_points + 2, pts );
1166
1167          /* now consider hinting */
1168          if ( IS_HINTED( loader->load_flags ) && n_ins > 0 )
1169          {
1170            exec->is_composite     = TRUE;
1171            exec->pedantic_hinting =
1172              (FT_Bool)( loader->load_flags & FT_LOAD_PEDANTIC );
1173
1174            error = TT_Run_Context( exec, ((TT_Size)loader->size)->debug );
1175            if ( error && exec->pedantic_hinting )
1176              goto Fail;
1177          }
1178
1179          /* save glyph origin and advance points */
1180          loader->pp1 = pp1[0];
1181          loader->pp2 = pp1[1];
1182        }
1183
1184#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
1185
1186      }
1187      /* end of composite loading */
1188    }
1189
1190    /***********************************************************************/
1191    /***********************************************************************/
1192    /***********************************************************************/
1193
1194  Fail:
1195    if ( opened_frame )
1196      face->forget_glyph_frame( loader );
1197
1198  Exit:
1199    return error;
1200  }
1201
1202
1203  static void
1204  compute_glyph_metrics( TT_Loader   loader,
1205                         FT_UInt     glyph_index )
1206  {
1207    FT_BBox       bbox;
1208    TT_Face       face = (TT_Face)loader->face;
1209    FT_Fixed      y_scale;
1210    TT_GlyphSlot  glyph = loader->glyph;
1211    TT_Size       size = (TT_Size)loader->size;
1212
1213
1214    y_scale = 0x10000L;
1215    if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 )
1216      y_scale = size->root.metrics.y_scale;
1217
1218    if ( glyph->format != ft_glyph_format_composite )
1219    {
1220      glyph->outline.flags &= ~ft_outline_single_pass;
1221
1222      /* copy outline to our glyph slot */
1223      FT_GlyphLoader_CopyPoints( glyph->internal->loader, loader->gloader );
1224      glyph->outline = glyph->internal->loader->base.outline;
1225
1226      /* translate array so that (0,0) is the glyph's origin */
1227      FT_Outline_Translate( &glyph->outline, -loader->pp1.x, 0 );
1228
1229      FT_Outline_Get_CBox( &glyph->outline, &bbox );
1230
1231      if ( IS_HINTED( loader->load_flags ) )
1232      {
1233        /* grid-fit the bounding box */
1234        bbox.xMin &= -64;
1235        bbox.yMin &= -64;
1236        bbox.xMax  = ( bbox.xMax + 63 ) & -64;
1237        bbox.yMax  = ( bbox.yMax + 63 ) & -64;
1238      }
1239    }
1240    else
1241      bbox = loader->bbox;
1242
1243    /* get the device-independent horizontal advance.  It is scaled later */
1244    /* by the base layer.                                                 */
1245    {
1246      FT_Pos  advance = loader->linear;
1247
1248
1249      /* the flag FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH was introduced to */
1250      /* correctly support DynaLab fonts, which have an incorrect       */
1251      /* `advance_Width_Max' field!  It is used, to my knowledge,       */
1252      /* exclusively in the X-TrueType font server.                     */
1253      /*                                                                */
1254      if ( face->postscript.isFixedPitch                                     &&
1255           ( loader->load_flags & FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ) == 0 )
1256        advance = face->horizontal.advance_Width_Max;
1257
1258      /* we need to return the advance in font units in linearHoriAdvance, */
1259      /* it will be scaled later by the base layer.                        */
1260      glyph->linearHoriAdvance = advance;
1261    }
1262
1263    glyph->metrics.horiBearingX = bbox.xMin;
1264    glyph->metrics.horiBearingY = bbox.yMax;
1265    glyph->metrics.horiAdvance  = loader->pp2.x - loader->pp1.x;
1266
1267    /* don't forget to hint the advance when we need to */
1268    if ( IS_HINTED( loader->load_flags ) )
1269      glyph->metrics.horiAdvance = ( glyph->metrics.horiAdvance + 32 ) & -64;
1270
1271    /* Now take care of vertical metrics.  In the case where there is    */
1272    /* no vertical information within the font (relatively common), make */
1273    /* up some metrics by `hand'...                                      */
1274
1275    {
1276      FT_Short   top_bearing;    /* vertical top side bearing (EM units) */
1277      FT_UShort  advance_height; /* vertical advance height   (EM units) */
1278
1279      FT_Pos     left;     /* scaled vertical left side bearing */
1280      FT_Pos     top;      /* scaled vertical top side bearing  */
1281      FT_Pos     advance;  /* scaled vertical advance height    */
1282
1283
1284      /* Get the unscaled `tsb' and `ah' */
1285      if ( face->vertical_info                   &&
1286           face->vertical.number_Of_VMetrics > 0 )
1287      {
1288        /* Don't assume that both the vertical header and vertical */
1289        /* metrics are present in the same font :-)                */
1290
1291        TT_Get_Metrics( (TT_HoriHeader*)&face->vertical,
1292                        glyph_index,
1293                        &top_bearing,
1294                        &advance_height );
1295      }
1296      else
1297      {
1298        /* Make up the distances from the horizontal header.   */
1299
1300        /* NOTE: The OS/2 values are the only `portable' ones, */
1301        /*       which is why we use them, if there is an OS/2 */
1302        /*       table in the font.  Otherwise, we use the     */
1303        /*       values defined in the horizontal header.      */
1304        /*                                                     */
1305        /* NOTE2: The sTypoDescender is negative, which is why */
1306        /*        we compute the baseline-to-baseline distance */
1307        /*        here with:                                   */
1308        /*             ascender - descender + linegap          */
1309        /*                                                     */
1310        if ( face->os2.version != 0xFFFFU )
1311        {
1312          top_bearing    = (FT_Short)( face->os2.sTypoLineGap / 2 );
1313          advance_height = (FT_UShort)( face->os2.sTypoAscender -
1314                                        face->os2.sTypoDescender +
1315                                        face->os2.sTypoLineGap );
1316        }
1317        else
1318        {
1319          top_bearing    = (FT_Short)( face->horizontal.Line_Gap / 2 );
1320          advance_height = (FT_UShort)( face->horizontal.Ascender  +
1321                                        face->horizontal.Descender +
1322                                        face->horizontal.Line_Gap );
1323        }
1324      }
1325
1326      /* We must adjust the top_bearing value from the bounding box given */
1327      /* in the glyph header to te bounding box calculated with           */
1328      /* FT_Get_Outline_CBox().                                           */
1329
1330      /* scale the metrics */
1331      if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) )
1332      {
1333        top     = FT_MulFix( top_bearing + loader->bbox.yMax, y_scale )
1334                    - bbox.yMax;
1335        advance = FT_MulFix( advance_height, y_scale );
1336      }
1337      else
1338      {
1339        top     = top_bearing + loader->bbox.yMax - bbox.yMax;
1340        advance = advance_height;
1341      }
1342
1343      /* set the advance height in design units.  It is scaled later by */
1344      /* the base layer.                                                */
1345      glyph->linearVertAdvance = advance_height;
1346
1347      /* XXX: for now, we have no better algorithm for the lsb, but it */
1348      /*      should work fine.                                        */
1349      /*                                                               */
1350      left = ( bbox.xMin - bbox.xMax ) / 2;
1351
1352      /* grid-fit them if necessary */
1353      if ( IS_HINTED( loader->load_flags ) )
1354      {
1355        left   &= -64;
1356        top     = ( top + 63     ) & -64;
1357        advance = ( advance + 32 ) & -64;
1358      }
1359
1360      glyph->metrics.vertBearingX = left;
1361      glyph->metrics.vertBearingY = top;
1362      glyph->metrics.vertAdvance  = advance;
1363    }
1364
1365    /* adjust advance width to the value contained in the hdmx table */
1366    if ( !face->postscript.isFixedPitch && size &&
1367         IS_HINTED( loader->load_flags )        )
1368    {
1369      FT_Byte*  widths = Get_Advance_Widths( face,
1370                                             size->root.metrics.x_ppem );
1371
1372
1373      if ( widths )
1374        glyph->metrics.horiAdvance = widths[glyph_index] << 6;
1375    }
1376
1377    /* set glyph dimensions */
1378    glyph->metrics.width  = bbox.xMax - bbox.xMin;
1379    glyph->metrics.height = bbox.yMax - bbox.yMin;
1380  }
1381
1382
1383  /*************************************************************************/
1384  /*                                                                       */
1385  /* <Function>                                                            */
1386  /*    TT_Load_Glyph                                                      */
1387  /*                                                                       */
1388  /* <Description>                                                         */
1389  /*    A function used to load a single glyph within a given glyph slot,  */
1390  /*    for a given size.                                                  */
1391  /*                                                                       */
1392  /* <Input>                                                               */
1393  /*    glyph       :: A handle to a target slot object where the glyph    */
1394  /*                   will be loaded.                                     */
1395  /*                                                                       */
1396  /*    size        :: A handle to the source face size at which the glyph */
1397  /*                   must be scaled/loaded.                              */
1398  /*                                                                       */
1399  /*    glyph_index :: The index of the glyph in the font file.            */
1400  /*                                                                       */
1401  /*    load_flags  :: A flag indicating what to load for this glyph.  The */
1402  /*                   FT_LOAD_XXX constants can be used to control the    */
1403  /*                   glyph loading process (e.g., whether the outline    */
1404  /*                   should be scaled, whether to load bitmaps or not,   */
1405  /*                   whether to hint the outline, etc).                  */
1406  /*                                                                       */
1407  /* <Return>                                                              */
1408  /*    FreeType error code.  0 means success.                             */
1409  /*                                                                       */
1410  FT_LOCAL_DEF( FT_Error )
1411  TT_Load_Glyph( TT_Size       size,
1412                 TT_GlyphSlot  glyph,
1413                 FT_UShort     glyph_index,
1414                 FT_UInt       load_flags )
1415  {
1416    SFNT_Service  sfnt;
1417    TT_Face       face;
1418    FT_Stream     stream;
1419    FT_Error      error;
1420    TT_LoaderRec  loader;
1421
1422
1423    face   = (TT_Face)glyph->face;
1424    sfnt   = (SFNT_Service)face->sfnt;
1425    stream = face->root.stream;
1426    error  = 0;
1427
1428    if ( !size || ( load_flags & FT_LOAD_NO_SCALE )   ||
1429                  ( load_flags & FT_LOAD_NO_RECURSE ) )
1430    {
1431      size        = NULL;
1432      load_flags |= FT_LOAD_NO_SCALE   |
1433                    FT_LOAD_NO_HINTING |
1434                    FT_LOAD_NO_BITMAP;
1435    }
1436
1437    glyph->num_subglyphs = 0;
1438
1439#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
1440
1441    /* try to load embedded bitmap if any              */
1442    /*                                                 */
1443    /* XXX: The convention should be emphasized in     */
1444    /*      the documents because it can be confusing. */
1445    if ( size                                    &&
1446         size->strike_index != 0xFFFFU           &&
1447         sfnt->load_sbits                        &&
1448         ( load_flags & FT_LOAD_NO_BITMAP ) == 0 )
1449
1450    {
1451      TT_SBit_MetricsRec  metrics;
1452
1453
1454      error = sfnt->load_sbit_image( face,
1455                                     size->strike_index,
1456                                     glyph_index,
1457                                     load_flags,
1458                                     stream,
1459                                     &glyph->bitmap,
1460                                     &metrics );
1461      if ( !error )
1462      {
1463        glyph->outline.n_points   = 0;
1464        glyph->outline.n_contours = 0;
1465
1466        glyph->metrics.width  = (FT_Pos)metrics.width  << 6;
1467        glyph->metrics.height = (FT_Pos)metrics.height << 6;
1468
1469        glyph->metrics.horiBearingX = (FT_Pos)metrics.horiBearingX << 6;
1470        glyph->metrics.horiBearingY = (FT_Pos)metrics.horiBearingY << 6;
1471        glyph->metrics.horiAdvance  = (FT_Pos)metrics.horiAdvance  << 6;
1472
1473        glyph->metrics.vertBearingX = (FT_Pos)metrics.vertBearingX << 6;
1474        glyph->metrics.vertBearingY = (FT_Pos)metrics.vertBearingY << 6;
1475        glyph->metrics.vertAdvance  = (FT_Pos)metrics.vertAdvance  << 6;
1476
1477        glyph->format = ft_glyph_format_bitmap;
1478        if ( load_flags & FT_LOAD_VERTICAL_LAYOUT )
1479        {
1480          glyph->bitmap_left = metrics.vertBearingX;
1481          glyph->bitmap_top  = metrics.vertBearingY;
1482        }
1483        else
1484        {
1485          glyph->bitmap_left = metrics.horiBearingX;
1486          glyph->bitmap_top  = metrics.horiBearingY;
1487        }
1488        return error;
1489      }
1490    }
1491
1492#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
1493
1494    /* return immediately if we only want the embedded bitmaps */
1495    if ( load_flags & FT_LOAD_SBITS_ONLY )
1496      return FT_Err_Invalid_Argument;
1497
1498    /* seek to the beginning of the glyph table.  For Type 42 fonts      */
1499    /* the table might be accessed from a Postscript stream or something */
1500    /* else...                                                           */
1501
1502    error = face->goto_table( face, TTAG_glyf, stream, 0 );
1503    if ( error )
1504    {
1505      FT_ERROR(( "TT_Load_Glyph: could not access glyph table\n" ));
1506      goto Exit;
1507    }
1508
1509    FT_MEM_SET( &loader, 0, sizeof ( loader ) );
1510
1511    /* update the glyph zone bounds */
1512    {
1513      FT_GlyphLoader  gloader = FT_FACE_DRIVER(face)->glyph_loader;
1514
1515
1516      loader.gloader = gloader;
1517
1518      FT_GlyphLoader_Rewind( gloader );
1519
1520      tt_prepare_zone( &loader.zone, &gloader->base, 0, 0 );
1521      tt_prepare_zone( &loader.base, &gloader->base, 0, 0 );
1522    }
1523
1524#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
1525
1526    if ( size )
1527    {
1528      /* query new execution context */
1529      loader.exec = size->debug ? size->context : TT_New_Context( face );
1530      if ( !loader.exec )
1531        return TT_Err_Could_Not_Find_Context;
1532
1533      TT_Load_Context( loader.exec, face, size );
1534      loader.instructions = loader.exec->glyphIns;
1535
1536      /* load default graphics state - if needed */
1537      if ( size->GS.instruct_control & 2 )
1538        loader.exec->GS = tt_default_graphics_state;
1539    }
1540
1541#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
1542
1543    /* clear all outline flags, except the `owner' one */
1544    glyph->outline.flags = 0;
1545
1546    /* let's initialize the rest of our loader now */
1547
1548    loader.load_flags    = load_flags;
1549
1550    loader.face   = (FT_Face)face;
1551    loader.size   = (FT_Size)size;
1552    loader.glyph  = (FT_GlyphSlot)glyph;
1553    loader.stream = stream;
1554
1555    loader.glyf_offset  = FT_STREAM_POS();
1556
1557#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
1558
1559    /* if the cvt program has disabled hinting, the argument */
1560    /* is ignored.                                           */
1561    if ( size && ( size->GS.instruct_control & 1 ) )
1562      loader.load_flags |= FT_LOAD_NO_HINTING;
1563
1564#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
1565
1566    /* Main loading loop */
1567    glyph->format        = ft_glyph_format_outline;
1568    glyph->num_subglyphs = 0;
1569
1570    error = load_truetype_glyph( &loader, glyph_index );
1571    if ( !error )
1572      compute_glyph_metrics( &loader, glyph_index );
1573
1574#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
1575
1576    if ( !size || !size->debug )
1577      TT_Done_Context( loader.exec );
1578
1579#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
1580
1581    /* Set the `high precision' bit flag.                           */
1582    /* This is _critical_ to get correct output for monochrome      */
1583    /* TrueType glyphs at all sizes using the bytecode interpreter. */
1584    /*                                                              */
1585    if ( size && size->root.metrics.y_ppem < 24 )
1586      glyph->outline.flags |= ft_outline_high_precision;
1587
1588  Exit:
1589    return error;
1590  }
1591
1592
1593/* END */
1594