1/***************************************************************************/
2/*                                                                         */
3/*  ttsbit.c                                                               */
4/*                                                                         */
5/*    TrueType and OpenType embedded bitmap support (body).                */
6/*                                                                         */
7/*  Copyright 2005-2017 by                                                 */
8/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
9/*                                                                         */
10/*  Copyright 2013 by Google, Inc.                                         */
11/*  Google Author(s): Behdad Esfahbod.                                     */
12/*                                                                         */
13/*  This file is part of the FreeType project, and may only be used,       */
14/*  modified, and distributed under the terms of the FreeType project      */
15/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
16/*  this file you indicate that you have read the license and              */
17/*  understand and accept it fully.                                        */
18/*                                                                         */
19/***************************************************************************/
20
21
22#include <ft2build.h>
23#include FT_INTERNAL_DEBUG_H
24#include FT_INTERNAL_STREAM_H
25#include FT_TRUETYPE_TAGS_H
26#include FT_BITMAP_H
27#include "ttsbit.h"
28
29#include "sferrors.h"
30
31#include "ttmtx.h"
32#include "pngshim.h"
33
34
35  /*************************************************************************/
36  /*                                                                       */
37  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
38  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
39  /* messages during execution.                                            */
40  /*                                                                       */
41#undef  FT_COMPONENT
42#define FT_COMPONENT  trace_ttsbit
43
44
45  FT_LOCAL_DEF( FT_Error )
46  tt_face_load_sbit( TT_Face    face,
47                     FT_Stream  stream )
48  {
49    FT_Error  error;
50    FT_ULong  table_size;
51    FT_ULong  table_start;
52
53
54    face->sbit_table       = NULL;
55    face->sbit_table_size  = 0;
56    face->sbit_table_type  = TT_SBIT_TABLE_TYPE_NONE;
57    face->sbit_num_strikes = 0;
58
59    error = face->goto_table( face, TTAG_CBLC, stream, &table_size );
60    if ( !error )
61      face->sbit_table_type = TT_SBIT_TABLE_TYPE_CBLC;
62    else
63    {
64      error = face->goto_table( face, TTAG_EBLC, stream, &table_size );
65      if ( error )
66        error = face->goto_table( face, TTAG_bloc, stream, &table_size );
67      if ( !error )
68        face->sbit_table_type = TT_SBIT_TABLE_TYPE_EBLC;
69    }
70
71    if ( error )
72    {
73      error = face->goto_table( face, TTAG_sbix, stream, &table_size );
74      if ( !error )
75        face->sbit_table_type = TT_SBIT_TABLE_TYPE_SBIX;
76    }
77    if ( error )
78      goto Exit;
79
80    if ( table_size < 8 )
81    {
82      FT_ERROR(( "tt_face_load_sbit_strikes: table too short\n" ));
83      error = FT_THROW( Invalid_File_Format );
84      goto Exit;
85    }
86
87    table_start = FT_STREAM_POS();
88
89    switch ( (FT_UInt)face->sbit_table_type )
90    {
91    case TT_SBIT_TABLE_TYPE_EBLC:
92    case TT_SBIT_TABLE_TYPE_CBLC:
93      {
94        FT_Byte*  p;
95        FT_Fixed  version;
96        FT_ULong  num_strikes;
97        FT_UInt   count;
98
99
100        if ( FT_FRAME_EXTRACT( table_size, face->sbit_table ) )
101          goto Exit;
102
103        face->sbit_table_size = table_size;
104
105        p = face->sbit_table;
106
107        version     = FT_NEXT_LONG( p );
108        num_strikes = FT_NEXT_ULONG( p );
109
110        /* there's at least one font (FZShuSong-Z01, version 3)   */
111        /* that uses the wrong byte order for the `version' field */
112        if ( ( (FT_ULong)version & 0xFFFF0000UL ) != 0x00020000UL &&
113             ( (FT_ULong)version & 0x0000FFFFUL ) != 0x00000200UL &&
114             ( (FT_ULong)version & 0xFFFF0000UL ) != 0x00030000UL &&
115             ( (FT_ULong)version & 0x0000FFFFUL ) != 0x00000300UL )
116        {
117          error = FT_THROW( Unknown_File_Format );
118          goto Exit;
119        }
120
121        if ( num_strikes >= 0x10000UL )
122        {
123          error = FT_THROW( Invalid_File_Format );
124          goto Exit;
125        }
126
127        /*
128         *  Count the number of strikes available in the table.  We are a bit
129         *  paranoid there and don't trust the data.
130         */
131        count = (FT_UInt)num_strikes;
132        if ( 8 + 48UL * count > table_size )
133          count = (FT_UInt)( ( table_size - 8 ) / 48 );
134
135        face->sbit_num_strikes = count;
136      }
137      break;
138
139    case TT_SBIT_TABLE_TYPE_SBIX:
140      {
141        FT_UShort  version;
142        FT_UShort  flags;
143        FT_ULong   num_strikes;
144        FT_UInt    count;
145
146
147        if ( FT_FRAME_ENTER( 8 ) )
148          goto Exit;
149
150        version     = FT_GET_USHORT();
151        flags       = FT_GET_USHORT();
152        num_strikes = FT_GET_ULONG();
153
154        FT_FRAME_EXIT();
155
156        if ( version < 1 )
157        {
158          error = FT_THROW( Unknown_File_Format );
159          goto Exit;
160        }
161
162        /* Bit 0 must always be `1'.                            */
163        /* Bit 1 controls the overlay of bitmaps with outlines. */
164        /* All other bits should be zero.                       */
165        if ( !( flags == 1 || flags == 3 ) ||
166             num_strikes >= 0x10000UL      )
167        {
168          error = FT_THROW( Invalid_File_Format );
169          goto Exit;
170        }
171
172        /* we currently don't support bit 1; however, it is better to */
173        /* draw at least something...                                 */
174        if ( flags == 3 )
175          FT_TRACE1(( "tt_face_load_sbit_strikes:"
176                      " sbix overlay not supported yet\n"
177                      "                          "
178                      " expect bad rendering results\n" ));
179
180        /*
181         *  Count the number of strikes available in the table.  We are a bit
182         *  paranoid there and don't trust the data.
183         */
184        count = (FT_UInt)num_strikes;
185        if ( 8 + 4UL * count > table_size )
186          count = (FT_UInt)( ( table_size - 8 ) / 4 );
187
188        if ( FT_STREAM_SEEK( FT_STREAM_POS() - 8 ) )
189          goto Exit;
190
191        face->sbit_table_size = 8 + count * 4;
192        if ( FT_FRAME_EXTRACT( face->sbit_table_size, face->sbit_table ) )
193          goto Exit;
194
195        face->sbit_num_strikes = count;
196      }
197      break;
198
199    default:
200      /* we ignore unknown table formats */
201      error = FT_THROW( Unknown_File_Format );
202      break;
203    }
204
205    if ( !error )
206      FT_TRACE3(( "tt_face_load_sbit_strikes: found %u strikes\n",
207                  face->sbit_num_strikes ));
208
209    face->ebdt_start = 0;
210    face->ebdt_size  = 0;
211
212    if ( face->sbit_table_type == TT_SBIT_TABLE_TYPE_SBIX )
213    {
214      /* the `sbix' table is self-contained; */
215      /* it has no associated data table     */
216      face->ebdt_start = table_start;
217      face->ebdt_size  = table_size;
218    }
219    else if ( face->sbit_table_type != TT_SBIT_TABLE_TYPE_NONE )
220    {
221      FT_ULong  ebdt_size;
222
223
224      error = face->goto_table( face, TTAG_CBDT, stream, &ebdt_size );
225      if ( error )
226        error = face->goto_table( face, TTAG_EBDT, stream, &ebdt_size );
227      if ( error )
228        error = face->goto_table( face, TTAG_bdat, stream, &ebdt_size );
229
230      if ( !error )
231      {
232        face->ebdt_start = FT_STREAM_POS();
233        face->ebdt_size  = ebdt_size;
234      }
235    }
236
237    if ( !face->ebdt_size )
238    {
239      FT_TRACE2(( "tt_face_load_sbit_strikes:"
240                  " no embedded bitmap data table found;\n"
241                  "                          "
242                  " resetting number of strikes to zero\n" ));
243      face->sbit_num_strikes = 0;
244    }
245
246    return FT_Err_Ok;
247
248  Exit:
249    if ( error )
250    {
251      if ( face->sbit_table )
252        FT_FRAME_RELEASE( face->sbit_table );
253      face->sbit_table_size = 0;
254      face->sbit_table_type = TT_SBIT_TABLE_TYPE_NONE;
255    }
256
257    return error;
258  }
259
260
261  FT_LOCAL_DEF( void )
262  tt_face_free_sbit( TT_Face  face )
263  {
264    FT_Stream  stream = face->root.stream;
265
266
267    FT_FRAME_RELEASE( face->sbit_table );
268    face->sbit_table_size  = 0;
269    face->sbit_table_type  = TT_SBIT_TABLE_TYPE_NONE;
270    face->sbit_num_strikes = 0;
271  }
272
273
274  FT_LOCAL_DEF( FT_Error )
275  tt_face_set_sbit_strike( TT_Face          face,
276                           FT_Size_Request  req,
277                           FT_ULong*        astrike_index )
278  {
279    return FT_Match_Size( (FT_Face)face, req, 0, astrike_index );
280  }
281
282
283  FT_LOCAL_DEF( FT_Error )
284  tt_face_load_strike_metrics( TT_Face           face,
285                               FT_ULong          strike_index,
286                               FT_Size_Metrics*  metrics )
287  {
288    /* we have to test for the existence of `sbit_strike_map'    */
289    /* because the function gets also used at the very beginning */
290    /* to construct `sbit_strike_map' itself                     */
291    if ( face->sbit_strike_map )
292    {
293      if ( strike_index >= (FT_ULong)face->root.num_fixed_sizes )
294        return FT_THROW( Invalid_Argument );
295
296      /* map to real index */
297      strike_index = face->sbit_strike_map[strike_index];
298    }
299    else
300    {
301      if ( strike_index >= (FT_ULong)face->sbit_num_strikes )
302        return FT_THROW( Invalid_Argument );
303    }
304
305    switch ( (FT_UInt)face->sbit_table_type )
306    {
307    case TT_SBIT_TABLE_TYPE_EBLC:
308    case TT_SBIT_TABLE_TYPE_CBLC:
309      {
310        FT_Byte*  strike;
311        FT_Char   max_before_bl;
312        FT_Char   min_after_bl;
313
314
315        strike = face->sbit_table + 8 + strike_index * 48;
316
317        metrics->x_ppem = (FT_UShort)strike[44];
318        metrics->y_ppem = (FT_UShort)strike[45];
319
320        metrics->ascender  = (FT_Char)strike[16] * 64;  /* hori.ascender  */
321        metrics->descender = (FT_Char)strike[17] * 64;  /* hori.descender */
322
323        /* Due to fuzzy wording in the EBLC documentation, we find both */
324        /* positive and negative values for `descender'.  Additionally, */
325        /* many fonts have both `ascender' and `descender' set to zero  */
326        /* (which is definitely wrong).  MS Windows simply ignores all  */
327        /* those values...  For these reasons we apply some heuristics  */
328        /* to get a reasonable, non-zero value for the height.          */
329
330        max_before_bl = (FT_Char)strike[24];
331        min_after_bl  = (FT_Char)strike[25];
332
333        if ( metrics->descender > 0 )
334        {
335          /* compare sign of descender with `min_after_bl' */
336          if ( min_after_bl < 0 )
337            metrics->descender = -metrics->descender;
338        }
339
340        else if ( metrics->descender == 0 )
341        {
342          if ( metrics->ascender == 0 )
343          {
344            FT_TRACE2(( "tt_face_load_strike_metrics:"
345                        " sanitizing invalid ascender and descender\n"
346                        "                            "
347                        " values for strike %d (%dppem, %dppem)\n",
348                        strike_index,
349                        metrics->x_ppem, metrics->y_ppem ));
350
351            /* sanitize buggy ascender and descender values */
352            if ( max_before_bl || min_after_bl )
353            {
354              metrics->ascender  = max_before_bl * 64;
355              metrics->descender = min_after_bl * 64;
356            }
357            else
358            {
359              metrics->ascender  = metrics->y_ppem * 64;
360              metrics->descender = 0;
361            }
362          }
363        }
364
365#if 0
366        else
367          ; /* if we have a negative descender, simply use it */
368#endif
369
370        metrics->height = metrics->ascender - metrics->descender;
371        if ( metrics->height == 0 )
372        {
373          FT_TRACE2(( "tt_face_load_strike_metrics:"
374                      " sanitizing invalid height value\n"
375                      "                            "
376                      " for strike (%d, %d)\n",
377                      metrics->x_ppem, metrics->y_ppem ));
378          metrics->height    = metrics->y_ppem * 64;
379          metrics->descender = metrics->ascender - metrics->height;
380        }
381
382        /* Is this correct? */
383        metrics->max_advance = ( (FT_Char)strike[22] + /* min_origin_SB  */
384                                          strike[18] + /* max_width      */
385                                 (FT_Char)strike[23]   /* min_advance_SB */
386                                                     ) * 64;
387
388        /* set the scale values (in 16.16 units) so advances */
389        /* from the hmtx and vmtx table are scaled correctly */
390        metrics->x_scale = FT_MulDiv( metrics->x_ppem,
391                                      64 * 0x10000,
392                                      face->header.Units_Per_EM );
393        metrics->y_scale = FT_MulDiv( metrics->y_ppem,
394                                      64 * 0x10000,
395                                      face->header.Units_Per_EM );
396
397        return FT_Err_Ok;
398      }
399
400    case TT_SBIT_TABLE_TYPE_SBIX:
401      {
402        FT_Stream       stream = face->root.stream;
403        FT_UInt         offset;
404        FT_UShort       upem, ppem, resolution;
405        TT_HoriHeader  *hori;
406        FT_Pos          ppem_; /* to reduce casts */
407
408        FT_Error  error;
409        FT_Byte*  p;
410
411
412        p      = face->sbit_table + 8 + 4 * strike_index;
413        offset = FT_NEXT_ULONG( p );
414
415        if ( offset + 4 > face->ebdt_size )
416          return FT_THROW( Invalid_File_Format );
417
418        if ( FT_STREAM_SEEK( face->ebdt_start + offset ) ||
419             FT_FRAME_ENTER( 4 )                         )
420          return error;
421
422        ppem       = FT_GET_USHORT();
423        resolution = FT_GET_USHORT();
424
425        FT_UNUSED( resolution ); /* What to do with this? */
426
427        FT_FRAME_EXIT();
428
429        upem = face->header.Units_Per_EM;
430        hori = &face->horizontal;
431
432        metrics->x_ppem = ppem;
433        metrics->y_ppem = ppem;
434
435        ppem_ = (FT_Pos)ppem;
436
437        metrics->ascender =
438          FT_MulDiv( hori->Ascender, ppem_ * 64, upem );
439        metrics->descender =
440          FT_MulDiv( hori->Descender, ppem_ * 64, upem );
441        metrics->height =
442          FT_MulDiv( hori->Ascender - hori->Descender + hori->Line_Gap,
443                     ppem_ * 64, upem );
444        metrics->max_advance =
445          FT_MulDiv( hori->advance_Width_Max, ppem_ * 64, upem );
446
447        return error;
448      }
449
450    default:
451      return FT_THROW( Unknown_File_Format );
452    }
453  }
454
455
456  typedef struct  TT_SBitDecoderRec_
457  {
458    TT_Face          face;
459    FT_Stream        stream;
460    FT_Bitmap*       bitmap;
461    TT_SBit_Metrics  metrics;
462    FT_Bool          metrics_loaded;
463    FT_Bool          bitmap_allocated;
464    FT_Byte          bit_depth;
465
466    FT_ULong         ebdt_start;
467    FT_ULong         ebdt_size;
468
469    FT_ULong         strike_index_array;
470    FT_ULong         strike_index_count;
471    FT_Byte*         eblc_base;
472    FT_Byte*         eblc_limit;
473
474  } TT_SBitDecoderRec, *TT_SBitDecoder;
475
476
477  static FT_Error
478  tt_sbit_decoder_init( TT_SBitDecoder       decoder,
479                        TT_Face              face,
480                        FT_ULong             strike_index,
481                        TT_SBit_MetricsRec*  metrics )
482  {
483    FT_Error   error  = FT_ERR( Table_Missing );
484    FT_Stream  stream = face->root.stream;
485
486
487    strike_index = face->sbit_strike_map[strike_index];
488
489    if ( !face->ebdt_size )
490      goto Exit;
491    if ( FT_STREAM_SEEK( face->ebdt_start ) )
492      goto Exit;
493
494    decoder->face    = face;
495    decoder->stream  = stream;
496    decoder->bitmap  = &face->root.glyph->bitmap;
497    decoder->metrics = metrics;
498
499    decoder->metrics_loaded   = 0;
500    decoder->bitmap_allocated = 0;
501
502    decoder->ebdt_start = face->ebdt_start;
503    decoder->ebdt_size  = face->ebdt_size;
504
505    decoder->eblc_base  = face->sbit_table;
506    decoder->eblc_limit = face->sbit_table + face->sbit_table_size;
507
508    /* now find the strike corresponding to the index */
509    {
510      FT_Byte*  p;
511
512
513      if ( 8 + 48 * strike_index + 3 * 4 + 34 + 1 > face->sbit_table_size )
514      {
515        error = FT_THROW( Invalid_File_Format );
516        goto Exit;
517      }
518
519      p = decoder->eblc_base + 8 + 48 * strike_index;
520
521      decoder->strike_index_array = FT_NEXT_ULONG( p );
522      p                          += 4;
523      decoder->strike_index_count = FT_NEXT_ULONG( p );
524      p                          += 34;
525      decoder->bit_depth          = *p;
526
527      /* decoder->strike_index_array +                               */
528      /*   8 * decoder->strike_index_count > face->sbit_table_size ? */
529      if ( decoder->strike_index_array > face->sbit_table_size           ||
530           decoder->strike_index_count >
531             ( face->sbit_table_size - decoder->strike_index_array ) / 8 )
532        error = FT_THROW( Invalid_File_Format );
533    }
534
535  Exit:
536    return error;
537  }
538
539
540  static void
541  tt_sbit_decoder_done( TT_SBitDecoder  decoder )
542  {
543    FT_UNUSED( decoder );
544  }
545
546
547  static FT_Error
548  tt_sbit_decoder_alloc_bitmap( TT_SBitDecoder  decoder,
549                                FT_Bool         metrics_only )
550  {
551    FT_Error    error = FT_Err_Ok;
552    FT_UInt     width, height;
553    FT_Bitmap*  map = decoder->bitmap;
554    FT_ULong    size;
555
556
557    if ( !decoder->metrics_loaded )
558    {
559      error = FT_THROW( Invalid_Argument );
560      goto Exit;
561    }
562
563    width  = decoder->metrics->width;
564    height = decoder->metrics->height;
565
566    map->width = width;
567    map->rows  = height;
568
569    switch ( decoder->bit_depth )
570    {
571    case 1:
572      map->pixel_mode = FT_PIXEL_MODE_MONO;
573      map->pitch      = (int)( ( map->width + 7 ) >> 3 );
574      map->num_grays  = 2;
575      break;
576
577    case 2:
578      map->pixel_mode = FT_PIXEL_MODE_GRAY2;
579      map->pitch      = (int)( ( map->width + 3 ) >> 2 );
580      map->num_grays  = 4;
581      break;
582
583    case 4:
584      map->pixel_mode = FT_PIXEL_MODE_GRAY4;
585      map->pitch      = (int)( ( map->width + 1 ) >> 1 );
586      map->num_grays  = 16;
587      break;
588
589    case 8:
590      map->pixel_mode = FT_PIXEL_MODE_GRAY;
591      map->pitch      = (int)( map->width );
592      map->num_grays  = 256;
593      break;
594
595    case 32:
596      map->pixel_mode = FT_PIXEL_MODE_BGRA;
597      map->pitch      = (int)( map->width * 4 );
598      map->num_grays  = 256;
599      break;
600
601    default:
602      error = FT_THROW( Invalid_File_Format );
603      goto Exit;
604    }
605
606    size = map->rows * (FT_ULong)map->pitch;
607
608    /* check that there is no empty image */
609    if ( size == 0 )
610      goto Exit;     /* exit successfully! */
611
612    if ( metrics_only )
613      goto Exit;     /* only metrics are requested */
614
615    error = ft_glyphslot_alloc_bitmap( decoder->face->root.glyph, size );
616    if ( error )
617      goto Exit;
618
619    decoder->bitmap_allocated = 1;
620
621  Exit:
622    return error;
623  }
624
625
626  static FT_Error
627  tt_sbit_decoder_load_metrics( TT_SBitDecoder  decoder,
628                                FT_Byte*       *pp,
629                                FT_Byte*        limit,
630                                FT_Bool         big )
631  {
632    FT_Byte*         p       = *pp;
633    TT_SBit_Metrics  metrics = decoder->metrics;
634
635
636    if ( p + 5 > limit )
637      goto Fail;
638
639    metrics->height       = p[0];
640    metrics->width        = p[1];
641    metrics->horiBearingX = (FT_Char)p[2];
642    metrics->horiBearingY = (FT_Char)p[3];
643    metrics->horiAdvance  = p[4];
644
645    p += 5;
646    if ( big )
647    {
648      if ( p + 3 > limit )
649        goto Fail;
650
651      metrics->vertBearingX = (FT_Char)p[0];
652      metrics->vertBearingY = (FT_Char)p[1];
653      metrics->vertAdvance  = p[2];
654
655      p += 3;
656    }
657    else
658    {
659      /* avoid uninitialized data in case there is no vertical info -- */
660      metrics->vertBearingX = 0;
661      metrics->vertBearingY = 0;
662      metrics->vertAdvance  = 0;
663    }
664
665    decoder->metrics_loaded = 1;
666    *pp = p;
667    return FT_Err_Ok;
668
669  Fail:
670    FT_TRACE1(( "tt_sbit_decoder_load_metrics: broken table\n" ));
671    return FT_THROW( Invalid_Argument );
672  }
673
674
675  /* forward declaration */
676  static FT_Error
677  tt_sbit_decoder_load_image( TT_SBitDecoder  decoder,
678                              FT_UInt         glyph_index,
679                              FT_Int          x_pos,
680                              FT_Int          y_pos,
681                              FT_UInt         recurse_count,
682                              FT_Bool         metrics_only );
683
684  typedef FT_Error  (*TT_SBitDecoder_LoadFunc)(
685                      TT_SBitDecoder  decoder,
686                      FT_Byte*        p,
687                      FT_Byte*        plimit,
688                      FT_Int          x_pos,
689                      FT_Int          y_pos,
690                      FT_UInt         recurse_count );
691
692
693  static FT_Error
694  tt_sbit_decoder_load_byte_aligned( TT_SBitDecoder  decoder,
695                                     FT_Byte*        p,
696                                     FT_Byte*        limit,
697                                     FT_Int          x_pos,
698                                     FT_Int          y_pos,
699                                     FT_UInt         recurse_count )
700  {
701    FT_Error    error = FT_Err_Ok;
702    FT_Byte*    line;
703    FT_Int      pitch, width, height, line_bits, h;
704    FT_UInt     bit_height, bit_width;
705    FT_Bitmap*  bitmap;
706
707    FT_UNUSED( recurse_count );
708
709
710    /* check that we can write the glyph into the bitmap */
711    bitmap     = decoder->bitmap;
712    bit_width  = bitmap->width;
713    bit_height = bitmap->rows;
714    pitch      = bitmap->pitch;
715    line       = bitmap->buffer;
716
717    width  = decoder->metrics->width;
718    height = decoder->metrics->height;
719
720    line_bits = width * decoder->bit_depth;
721
722    if ( x_pos < 0 || (FT_UInt)( x_pos + width ) > bit_width   ||
723         y_pos < 0 || (FT_UInt)( y_pos + height ) > bit_height )
724    {
725      FT_TRACE1(( "tt_sbit_decoder_load_byte_aligned:"
726                  " invalid bitmap dimensions\n" ));
727      error = FT_THROW( Invalid_File_Format );
728      goto Exit;
729    }
730
731    if ( p + ( ( line_bits + 7 ) >> 3 ) * height > limit )
732    {
733      FT_TRACE1(( "tt_sbit_decoder_load_byte_aligned: broken bitmap\n" ));
734      error = FT_THROW( Invalid_File_Format );
735      goto Exit;
736    }
737
738    /* now do the blit */
739    line  += y_pos * pitch + ( x_pos >> 3 );
740    x_pos &= 7;
741
742    if ( x_pos == 0 )  /* the easy one */
743    {
744      for ( h = height; h > 0; h--, line += pitch )
745      {
746        FT_Byte*  pwrite = line;
747        FT_Int    w;
748
749
750        for ( w = line_bits; w >= 8; w -= 8 )
751        {
752          pwrite[0] = (FT_Byte)( pwrite[0] | *p++ );
753          pwrite   += 1;
754        }
755
756        if ( w > 0 )
757          pwrite[0] = (FT_Byte)( pwrite[0] | ( *p++ & ( 0xFF00U >> w ) ) );
758      }
759    }
760    else  /* x_pos > 0 */
761    {
762      for ( h = height; h > 0; h--, line += pitch )
763      {
764        FT_Byte*  pwrite = line;
765        FT_Int    w;
766        FT_UInt   wval = 0;
767
768
769        for ( w = line_bits; w >= 8; w -= 8 )
770        {
771          wval       = (FT_UInt)( wval | *p++ );
772          pwrite[0]  = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) );
773          pwrite    += 1;
774          wval     <<= 8;
775        }
776
777        if ( w > 0 )
778          wval = (FT_UInt)( wval | ( *p++ & ( 0xFF00U >> w ) ) );
779
780        /* all bits read and there are `x_pos + w' bits to be written */
781
782        pwrite[0] = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) );
783
784        if ( x_pos + w > 8 )
785        {
786          pwrite++;
787          wval     <<= 8;
788          pwrite[0]  = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) );
789        }
790      }
791    }
792
793  Exit:
794    if ( !error )
795      FT_TRACE3(( "tt_sbit_decoder_load_byte_aligned: loaded\n" ));
796    return error;
797  }
798
799
800  /*
801   * Load a bit-aligned bitmap (with pointer `p') into a line-aligned bitmap
802   * (with pointer `pwrite').  In the example below, the width is 3 pixel,
803   * and `x_pos' is 1 pixel.
804   *
805   *       p                               p+1
806   *     |                               |                               |
807   *     | 7   6   5   4   3   2   1   0 | 7   6   5   4   3   2   1   0 |...
808   *     |                               |                               |
809   *       +-------+   +-------+   +-------+ ...
810   *           .           .           .
811   *           .           .           .
812   *           v           .           .
813   *       +-------+       .           .
814   * |                               | .
815   * | 7   6   5   4   3   2   1   0 | .
816   * |                               | .
817   *   pwrite              .           .
818   *                       .           .
819   *                       v           .
820   *                   +-------+       .
821   *             |                               |
822   *             | 7   6   5   4   3   2   1   0 |
823   *             |                               |
824   *               pwrite+1            .
825   *                                   .
826   *                                   v
827   *                               +-------+
828   *                         |                               |
829   *                         | 7   6   5   4   3   2   1   0 |
830   *                         |                               |
831   *                           pwrite+2
832   *
833   */
834
835  static FT_Error
836  tt_sbit_decoder_load_bit_aligned( TT_SBitDecoder  decoder,
837                                    FT_Byte*        p,
838                                    FT_Byte*        limit,
839                                    FT_Int          x_pos,
840                                    FT_Int          y_pos,
841                                    FT_UInt         recurse_count )
842  {
843    FT_Error    error = FT_Err_Ok;
844    FT_Byte*    line;
845    FT_Int      pitch, width, height, line_bits, h, nbits;
846    FT_UInt     bit_height, bit_width;
847    FT_Bitmap*  bitmap;
848    FT_UShort   rval;
849
850    FT_UNUSED( recurse_count );
851
852
853    /* check that we can write the glyph into the bitmap */
854    bitmap     = decoder->bitmap;
855    bit_width  = bitmap->width;
856    bit_height = bitmap->rows;
857    pitch      = bitmap->pitch;
858    line       = bitmap->buffer;
859
860    width  = decoder->metrics->width;
861    height = decoder->metrics->height;
862
863    line_bits = width * decoder->bit_depth;
864
865    if ( x_pos < 0 || (FT_UInt)( x_pos + width ) > bit_width   ||
866         y_pos < 0 || (FT_UInt)( y_pos + height ) > bit_height )
867    {
868      FT_TRACE1(( "tt_sbit_decoder_load_bit_aligned:"
869                  " invalid bitmap dimensions\n" ));
870      error = FT_THROW( Invalid_File_Format );
871      goto Exit;
872    }
873
874    if ( p + ( ( line_bits * height + 7 ) >> 3 ) > limit )
875    {
876      FT_TRACE1(( "tt_sbit_decoder_load_bit_aligned: broken bitmap\n" ));
877      error = FT_THROW( Invalid_File_Format );
878      goto Exit;
879    }
880
881    if ( !line_bits || !height )
882    {
883      /* nothing to do */
884      goto Exit;
885    }
886
887    /* now do the blit */
888
889    /* adjust `line' to point to the first byte of the bitmap */
890    line  += y_pos * pitch + ( x_pos >> 3 );
891    x_pos &= 7;
892
893    /* the higher byte of `rval' is used as a buffer */
894    rval  = 0;
895    nbits = 0;
896
897    for ( h = height; h > 0; h--, line += pitch )
898    {
899      FT_Byte*  pwrite = line;
900      FT_Int    w      = line_bits;
901
902
903      /* handle initial byte (in target bitmap) specially if necessary */
904      if ( x_pos )
905      {
906        w = ( line_bits < 8 - x_pos ) ? line_bits : 8 - x_pos;
907
908        if ( h == height )
909        {
910          rval  = *p++;
911          nbits = x_pos;
912        }
913        else if ( nbits < w )
914        {
915          if ( p < limit )
916            rval |= *p++;
917          nbits += 8 - w;
918        }
919        else
920        {
921          rval  >>= 8;
922          nbits  -= w;
923        }
924
925        *pwrite++ |= ( ( rval >> nbits ) & 0xFF ) &
926                     ( ~( 0xFFU << w ) << ( 8 - w - x_pos ) );
927        rval     <<= 8;
928
929        w = line_bits - w;
930      }
931
932      /* handle medial bytes */
933      for ( ; w >= 8; w -= 8 )
934      {
935        rval      |= *p++;
936        *pwrite++ |= ( rval >> nbits ) & 0xFF;
937
938        rval <<= 8;
939      }
940
941      /* handle final byte if necessary */
942      if ( w > 0 )
943      {
944        if ( nbits < w )
945        {
946          if ( p < limit )
947            rval |= *p++;
948          *pwrite |= ( ( rval >> nbits ) & 0xFF ) & ( 0xFF00U >> w );
949          nbits   += 8 - w;
950
951          rval <<= 8;
952        }
953        else
954        {
955          *pwrite |= ( ( rval >> nbits ) & 0xFF ) & ( 0xFF00U >> w );
956          nbits   -= w;
957        }
958      }
959    }
960
961  Exit:
962    if ( !error )
963      FT_TRACE3(( "tt_sbit_decoder_load_bit_aligned: loaded\n" ));
964    return error;
965  }
966
967
968  static FT_Error
969  tt_sbit_decoder_load_compound( TT_SBitDecoder  decoder,
970                                 FT_Byte*        p,
971                                 FT_Byte*        limit,
972                                 FT_Int          x_pos,
973                                 FT_Int          y_pos,
974                                 FT_UInt         recurse_count )
975  {
976    FT_Error  error = FT_Err_Ok;
977    FT_UInt   num_components, nn;
978
979    FT_Char  horiBearingX = (FT_Char)decoder->metrics->horiBearingX;
980    FT_Char  horiBearingY = (FT_Char)decoder->metrics->horiBearingY;
981    FT_Byte  horiAdvance  = (FT_Byte)decoder->metrics->horiAdvance;
982    FT_Char  vertBearingX = (FT_Char)decoder->metrics->vertBearingX;
983    FT_Char  vertBearingY = (FT_Char)decoder->metrics->vertBearingY;
984    FT_Byte  vertAdvance  = (FT_Byte)decoder->metrics->vertAdvance;
985
986
987    if ( p + 2 > limit )
988      goto Fail;
989
990    num_components = FT_NEXT_USHORT( p );
991    if ( p + 4 * num_components > limit )
992    {
993      FT_TRACE1(( "tt_sbit_decoder_load_compound: broken table\n" ));
994      goto Fail;
995    }
996
997    FT_TRACE3(( "tt_sbit_decoder_load_compound: loading %d components\n",
998                num_components ));
999
1000    for ( nn = 0; nn < num_components; nn++ )
1001    {
1002      FT_UInt  gindex = FT_NEXT_USHORT( p );
1003      FT_Byte  dx     = FT_NEXT_BYTE( p );
1004      FT_Byte  dy     = FT_NEXT_BYTE( p );
1005
1006
1007      /* NB: a recursive call */
1008      error = tt_sbit_decoder_load_image( decoder,
1009                                          gindex,
1010                                          x_pos + dx,
1011                                          y_pos + dy,
1012                                          recurse_count + 1,
1013                                          /* request full bitmap image */
1014                                          FALSE );
1015      if ( error )
1016        break;
1017    }
1018
1019    FT_TRACE3(( "tt_sbit_decoder_load_compound: done\n" ));
1020
1021    decoder->metrics->horiBearingX = horiBearingX;
1022    decoder->metrics->horiBearingY = horiBearingY;
1023    decoder->metrics->horiAdvance  = horiAdvance;
1024    decoder->metrics->vertBearingX = vertBearingX;
1025    decoder->metrics->vertBearingY = vertBearingY;
1026    decoder->metrics->vertAdvance  = vertAdvance;
1027    decoder->metrics->width        = (FT_Byte)decoder->bitmap->width;
1028    decoder->metrics->height       = (FT_Byte)decoder->bitmap->rows;
1029
1030  Exit:
1031    return error;
1032
1033  Fail:
1034    error = FT_THROW( Invalid_File_Format );
1035    goto Exit;
1036  }
1037
1038
1039#ifdef FT_CONFIG_OPTION_USE_PNG
1040
1041  static FT_Error
1042  tt_sbit_decoder_load_png( TT_SBitDecoder  decoder,
1043                            FT_Byte*        p,
1044                            FT_Byte*        limit,
1045                            FT_Int          x_pos,
1046                            FT_Int          y_pos,
1047                            FT_UInt         recurse_count )
1048  {
1049    FT_Error  error = FT_Err_Ok;
1050    FT_ULong  png_len;
1051
1052    FT_UNUSED( recurse_count );
1053
1054
1055    if ( limit - p < 4 )
1056    {
1057      FT_TRACE1(( "tt_sbit_decoder_load_png: broken bitmap\n" ));
1058      error = FT_THROW( Invalid_File_Format );
1059      goto Exit;
1060    }
1061
1062    png_len = FT_NEXT_ULONG( p );
1063    if ( (FT_ULong)( limit - p ) < png_len )
1064    {
1065      FT_TRACE1(( "tt_sbit_decoder_load_png: broken bitmap\n" ));
1066      error = FT_THROW( Invalid_File_Format );
1067      goto Exit;
1068    }
1069
1070    error = Load_SBit_Png( decoder->face->root.glyph,
1071                           x_pos,
1072                           y_pos,
1073                           decoder->bit_depth,
1074                           decoder->metrics,
1075                           decoder->stream->memory,
1076                           p,
1077                           png_len,
1078                           FALSE,
1079                           FALSE );
1080
1081  Exit:
1082    if ( !error )
1083      FT_TRACE3(( "tt_sbit_decoder_load_png: loaded\n" ));
1084    return error;
1085  }
1086
1087#endif /* FT_CONFIG_OPTION_USE_PNG */
1088
1089
1090  static FT_Error
1091  tt_sbit_decoder_load_bitmap( TT_SBitDecoder  decoder,
1092                               FT_UInt         glyph_format,
1093                               FT_ULong        glyph_start,
1094                               FT_ULong        glyph_size,
1095                               FT_Int          x_pos,
1096                               FT_Int          y_pos,
1097                               FT_UInt         recurse_count,
1098                               FT_Bool         metrics_only )
1099  {
1100    FT_Error   error;
1101    FT_Stream  stream = decoder->stream;
1102    FT_Byte*   p;
1103    FT_Byte*   p_limit;
1104    FT_Byte*   data;
1105
1106
1107    /* seek into the EBDT table now */
1108    if ( !glyph_size                                   ||
1109         glyph_start + glyph_size > decoder->ebdt_size )
1110    {
1111      error = FT_THROW( Invalid_Argument );
1112      goto Exit;
1113    }
1114
1115    if ( FT_STREAM_SEEK( decoder->ebdt_start + glyph_start ) ||
1116         FT_FRAME_EXTRACT( glyph_size, data )                )
1117      goto Exit;
1118
1119    p       = data;
1120    p_limit = p + glyph_size;
1121
1122    /* read the data, depending on the glyph format */
1123    switch ( glyph_format )
1124    {
1125    case 1:
1126    case 2:
1127    case 8:
1128    case 17:
1129      error = tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 0 );
1130      break;
1131
1132    case 6:
1133    case 7:
1134    case 9:
1135    case 18:
1136      error = tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 );
1137      break;
1138
1139    default:
1140      error = FT_Err_Ok;
1141    }
1142
1143    if ( error )
1144      goto Fail;
1145
1146    {
1147      TT_SBitDecoder_LoadFunc  loader;
1148
1149
1150      switch ( glyph_format )
1151      {
1152      case 1:
1153      case 6:
1154        loader = tt_sbit_decoder_load_byte_aligned;
1155        break;
1156
1157      case 2:
1158      case 7:
1159        {
1160          /* Don't trust `glyph_format'.  For example, Apple's main Korean */
1161          /* system font, `AppleMyungJo.ttf' (version 7.0d2e6), uses glyph */
1162          /* format 7, but the data is format 6.  We check whether we have */
1163          /* an excessive number of bytes in the image: If it is equal to  */
1164          /* the value for a byte-aligned glyph, use the other loading     */
1165          /* routine.                                                      */
1166          /*                                                               */
1167          /* Note that for some (width,height) combinations, where the     */
1168          /* width is not a multiple of 8, the sizes for bit- and          */
1169          /* byte-aligned data are equal, for example (7,7) or (15,6).  We */
1170          /* then prefer what `glyph_format' specifies.                    */
1171
1172          FT_UInt  width  = decoder->metrics->width;
1173          FT_UInt  height = decoder->metrics->height;
1174
1175          FT_UInt  bit_size  = ( width * height + 7 ) >> 3;
1176          FT_UInt  byte_size = height * ( ( width + 7 ) >> 3 );
1177
1178
1179          if ( bit_size < byte_size                  &&
1180               byte_size == (FT_UInt)( p_limit - p ) )
1181            loader = tt_sbit_decoder_load_byte_aligned;
1182          else
1183            loader = tt_sbit_decoder_load_bit_aligned;
1184        }
1185        break;
1186
1187      case 5:
1188        loader = tt_sbit_decoder_load_bit_aligned;
1189        break;
1190
1191      case 8:
1192        if ( p + 1 > p_limit )
1193          goto Fail;
1194
1195        p += 1;  /* skip padding */
1196        /* fall-through */
1197
1198      case 9:
1199        loader = tt_sbit_decoder_load_compound;
1200        break;
1201
1202      case 17: /* small metrics, PNG image data   */
1203      case 18: /* big metrics, PNG image data     */
1204      case 19: /* metrics in EBLC, PNG image data */
1205#ifdef FT_CONFIG_OPTION_USE_PNG
1206        loader = tt_sbit_decoder_load_png;
1207        break;
1208#else
1209        error = FT_THROW( Unimplemented_Feature );
1210        goto Fail;
1211#endif /* FT_CONFIG_OPTION_USE_PNG */
1212
1213      default:
1214        error = FT_THROW( Invalid_Table );
1215        goto Fail;
1216      }
1217
1218      if ( !decoder->bitmap_allocated )
1219      {
1220        error = tt_sbit_decoder_alloc_bitmap( decoder, metrics_only );
1221
1222        if ( error )
1223          goto Fail;
1224      }
1225
1226      if ( metrics_only )
1227        goto Fail; /* this is not an error */
1228
1229      error = loader( decoder, p, p_limit, x_pos, y_pos, recurse_count );
1230    }
1231
1232  Fail:
1233    FT_FRAME_RELEASE( data );
1234
1235  Exit:
1236    return error;
1237  }
1238
1239
1240  static FT_Error
1241  tt_sbit_decoder_load_image( TT_SBitDecoder  decoder,
1242                              FT_UInt         glyph_index,
1243                              FT_Int          x_pos,
1244                              FT_Int          y_pos,
1245                              FT_UInt         recurse_count,
1246                              FT_Bool         metrics_only )
1247  {
1248    FT_Byte*  p          = decoder->eblc_base + decoder->strike_index_array;
1249    FT_Byte*  p_limit    = decoder->eblc_limit;
1250    FT_ULong  num_ranges = decoder->strike_index_count;
1251    FT_UInt   start, end, index_format, image_format;
1252    FT_ULong  image_start = 0, image_end = 0, image_offset;
1253
1254
1255    /* arbitrary recursion limit */
1256    if ( recurse_count > 100 )
1257    {
1258      FT_TRACE4(( "tt_sbit_decoder_load_image:"
1259                  " recursion depth exceeded\n" ));
1260      goto Failure;
1261    }
1262
1263
1264    /* First, we find the correct strike range that applies to this */
1265    /* glyph index.                                                 */
1266    for ( ; num_ranges > 0; num_ranges-- )
1267    {
1268      start = FT_NEXT_USHORT( p );
1269      end   = FT_NEXT_USHORT( p );
1270
1271      if ( glyph_index >= start && glyph_index <= end )
1272        goto FoundRange;
1273
1274      p += 4;  /* ignore index offset */
1275    }
1276    goto NoBitmap;
1277
1278  FoundRange:
1279    image_offset = FT_NEXT_ULONG( p );
1280
1281    /* overflow check */
1282    p = decoder->eblc_base + decoder->strike_index_array;
1283    if ( image_offset > (FT_ULong)( p_limit - p ) )
1284      goto Failure;
1285
1286    p += image_offset;
1287    if ( p + 8 > p_limit )
1288      goto NoBitmap;
1289
1290    /* now find the glyph's location and extend within the ebdt table */
1291    index_format = FT_NEXT_USHORT( p );
1292    image_format = FT_NEXT_USHORT( p );
1293    image_offset = FT_NEXT_ULONG ( p );
1294
1295    switch ( index_format )
1296    {
1297    case 1: /* 4-byte offsets relative to `image_offset' */
1298      p += 4 * ( glyph_index - start );
1299      if ( p + 8 > p_limit )
1300        goto NoBitmap;
1301
1302      image_start = FT_NEXT_ULONG( p );
1303      image_end   = FT_NEXT_ULONG( p );
1304
1305      if ( image_start == image_end )  /* missing glyph */
1306        goto NoBitmap;
1307      break;
1308
1309    case 2: /* big metrics, constant image size */
1310      {
1311        FT_ULong  image_size;
1312
1313
1314        if ( p + 12 > p_limit )
1315          goto NoBitmap;
1316
1317        image_size = FT_NEXT_ULONG( p );
1318
1319        if ( tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 ) )
1320          goto NoBitmap;
1321
1322        image_start = image_size * ( glyph_index - start );
1323        image_end   = image_start + image_size;
1324      }
1325      break;
1326
1327    case 3: /* 2-byte offsets relative to 'image_offset' */
1328      p += 2 * ( glyph_index - start );
1329      if ( p + 4 > p_limit )
1330        goto NoBitmap;
1331
1332      image_start = FT_NEXT_USHORT( p );
1333      image_end   = FT_NEXT_USHORT( p );
1334
1335      if ( image_start == image_end )  /* missing glyph */
1336        goto NoBitmap;
1337      break;
1338
1339    case 4: /* sparse glyph array with (glyph,offset) pairs */
1340      {
1341        FT_ULong  mm, num_glyphs;
1342
1343
1344        if ( p + 4 > p_limit )
1345          goto NoBitmap;
1346
1347        num_glyphs = FT_NEXT_ULONG( p );
1348
1349        /* overflow check for p + ( num_glyphs + 1 ) * 4 */
1350        if ( p + 4 > p_limit                                         ||
1351             num_glyphs > (FT_ULong)( ( ( p_limit - p ) >> 2 ) - 1 ) )
1352          goto NoBitmap;
1353
1354        for ( mm = 0; mm < num_glyphs; mm++ )
1355        {
1356          FT_UInt  gindex = FT_NEXT_USHORT( p );
1357
1358
1359          if ( gindex == glyph_index )
1360          {
1361            image_start = FT_NEXT_USHORT( p );
1362            p          += 2;
1363            image_end   = FT_PEEK_USHORT( p );
1364            break;
1365          }
1366          p += 2;
1367        }
1368
1369        if ( mm >= num_glyphs )
1370          goto NoBitmap;
1371      }
1372      break;
1373
1374    case 5: /* constant metrics with sparse glyph codes */
1375    case 19:
1376      {
1377        FT_ULong  image_size, mm, num_glyphs;
1378
1379
1380        if ( p + 16 > p_limit )
1381          goto NoBitmap;
1382
1383        image_size = FT_NEXT_ULONG( p );
1384
1385        if ( tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 ) )
1386          goto NoBitmap;
1387
1388        num_glyphs = FT_NEXT_ULONG( p );
1389
1390        /* overflow check for p + 2 * num_glyphs */
1391        if ( num_glyphs > (FT_ULong)( ( p_limit - p ) >> 1 ) )
1392          goto NoBitmap;
1393
1394        for ( mm = 0; mm < num_glyphs; mm++ )
1395        {
1396          FT_UInt  gindex = FT_NEXT_USHORT( p );
1397
1398
1399          if ( gindex == glyph_index )
1400            break;
1401        }
1402
1403        if ( mm >= num_glyphs )
1404          goto NoBitmap;
1405
1406        image_start = image_size * mm;
1407        image_end   = image_start + image_size;
1408      }
1409      break;
1410
1411    default:
1412      goto NoBitmap;
1413    }
1414
1415    if ( image_start > image_end )
1416      goto NoBitmap;
1417
1418    image_end  -= image_start;
1419    image_start = image_offset + image_start;
1420
1421    FT_TRACE3(( "tt_sbit_decoder_load_image:"
1422                " found sbit (format %d) for glyph index %d\n",
1423                image_format, glyph_index ));
1424
1425    return tt_sbit_decoder_load_bitmap( decoder,
1426                                        image_format,
1427                                        image_start,
1428                                        image_end,
1429                                        x_pos,
1430                                        y_pos,
1431                                        recurse_count,
1432                                        metrics_only );
1433
1434  Failure:
1435    return FT_THROW( Invalid_Table );
1436
1437  NoBitmap:
1438    FT_TRACE4(( "tt_sbit_decoder_load_image:"
1439                " no sbit found for glyph index %d\n", glyph_index ));
1440
1441    return FT_THROW( Invalid_Argument );
1442  }
1443
1444
1445  static FT_Error
1446  tt_face_load_sbix_image( TT_Face              face,
1447                           FT_ULong             strike_index,
1448                           FT_UInt              glyph_index,
1449                           FT_Stream            stream,
1450                           FT_Bitmap           *map,
1451                           TT_SBit_MetricsRec  *metrics,
1452                           FT_Bool              metrics_only )
1453  {
1454    FT_UInt   strike_offset, glyph_start, glyph_end;
1455    FT_Int    originOffsetX, originOffsetY;
1456    FT_Tag    graphicType;
1457    FT_Int    recurse_depth = 0;
1458
1459    FT_Error  error;
1460    FT_Byte*  p;
1461
1462    FT_UNUSED( map );
1463
1464
1465    strike_index = face->sbit_strike_map[strike_index];
1466
1467    metrics->width  = 0;
1468    metrics->height = 0;
1469
1470    p = face->sbit_table + 8 + 4 * strike_index;
1471    strike_offset = FT_NEXT_ULONG( p );
1472
1473  retry:
1474    if ( glyph_index > (FT_UInt)face->root.num_glyphs )
1475      return FT_THROW( Invalid_Argument );
1476
1477    if ( strike_offset >= face->ebdt_size                          ||
1478         face->ebdt_size - strike_offset < 4 + glyph_index * 4 + 8 )
1479      return FT_THROW( Invalid_File_Format );
1480
1481    if ( FT_STREAM_SEEK( face->ebdt_start  +
1482                         strike_offset + 4 +
1483                         glyph_index * 4   ) ||
1484         FT_FRAME_ENTER( 8 )                 )
1485      return error;
1486
1487    glyph_start = FT_GET_ULONG();
1488    glyph_end   = FT_GET_ULONG();
1489
1490    FT_FRAME_EXIT();
1491
1492    if ( glyph_start == glyph_end )
1493      return FT_THROW( Invalid_Argument );
1494    if ( glyph_start > glyph_end                     ||
1495         glyph_end - glyph_start < 8                 ||
1496         face->ebdt_size - strike_offset < glyph_end )
1497      return FT_THROW( Invalid_File_Format );
1498
1499    if ( FT_STREAM_SEEK( face->ebdt_start + strike_offset + glyph_start ) ||
1500         FT_FRAME_ENTER( glyph_end - glyph_start )                        )
1501      return error;
1502
1503    originOffsetX = FT_GET_SHORT();
1504    originOffsetY = FT_GET_SHORT();
1505
1506    graphicType = FT_GET_TAG4();
1507
1508    switch ( graphicType )
1509    {
1510    case FT_MAKE_TAG( 'd', 'u', 'p', 'e' ):
1511      if ( recurse_depth < 4 )
1512      {
1513        glyph_index = FT_GET_USHORT();
1514        FT_FRAME_EXIT();
1515        recurse_depth++;
1516        goto retry;
1517      }
1518      error = FT_THROW( Invalid_File_Format );
1519      break;
1520
1521    case FT_MAKE_TAG( 'p', 'n', 'g', ' ' ):
1522#ifdef FT_CONFIG_OPTION_USE_PNG
1523      error = Load_SBit_Png( face->root.glyph,
1524                             0,
1525                             0,
1526                             32,
1527                             metrics,
1528                             stream->memory,
1529                             stream->cursor,
1530                             glyph_end - glyph_start - 8,
1531                             TRUE,
1532                             metrics_only );
1533#else
1534      error = FT_THROW( Unimplemented_Feature );
1535#endif
1536      break;
1537
1538    case FT_MAKE_TAG( 'j', 'p', 'g', ' ' ):
1539    case FT_MAKE_TAG( 't', 'i', 'f', 'f' ):
1540    case FT_MAKE_TAG( 'r', 'g', 'b', 'l' ): /* used on iOS 7.1 */
1541      error = FT_THROW( Unknown_File_Format );
1542      break;
1543
1544    default:
1545      error = FT_THROW( Unimplemented_Feature );
1546      break;
1547    }
1548
1549    FT_FRAME_EXIT();
1550
1551    if ( !error )
1552    {
1553      FT_Short   abearing;
1554      FT_UShort  aadvance;
1555
1556
1557      tt_face_get_metrics( face, FALSE, glyph_index, &abearing, &aadvance );
1558
1559      metrics->horiBearingX = (FT_Short)originOffsetX;
1560      metrics->horiBearingY = (FT_Short)( -originOffsetY + metrics->height );
1561      metrics->horiAdvance  = (FT_UShort)( aadvance *
1562                                           face->root.size->metrics.x_ppem /
1563                                           face->header.Units_Per_EM );
1564    }
1565
1566    return error;
1567  }
1568
1569  FT_LOCAL( FT_Error )
1570  tt_face_load_sbit_image( TT_Face              face,
1571                           FT_ULong             strike_index,
1572                           FT_UInt              glyph_index,
1573                           FT_UInt              load_flags,
1574                           FT_Stream            stream,
1575                           FT_Bitmap           *map,
1576                           TT_SBit_MetricsRec  *metrics )
1577  {
1578    FT_Error  error = FT_Err_Ok;
1579
1580
1581    switch ( (FT_UInt)face->sbit_table_type )
1582    {
1583    case TT_SBIT_TABLE_TYPE_EBLC:
1584    case TT_SBIT_TABLE_TYPE_CBLC:
1585      {
1586        TT_SBitDecoderRec  decoder[1];
1587
1588
1589        error = tt_sbit_decoder_init( decoder, face, strike_index, metrics );
1590        if ( !error )
1591        {
1592          error = tt_sbit_decoder_load_image(
1593                    decoder,
1594                    glyph_index,
1595                    0,
1596                    0,
1597                    0,
1598                    ( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) != 0 );
1599          tt_sbit_decoder_done( decoder );
1600        }
1601      }
1602      break;
1603
1604    case TT_SBIT_TABLE_TYPE_SBIX:
1605      error = tt_face_load_sbix_image(
1606                face,
1607                strike_index,
1608                glyph_index,
1609                stream,
1610                map,
1611                metrics,
1612                ( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) != 0 );
1613      break;
1614
1615    default:
1616      error = FT_THROW( Unknown_File_Format );
1617      break;
1618    }
1619
1620    /* Flatten color bitmaps if color was not requested. */
1621    if ( !error                                        &&
1622         !( load_flags & FT_LOAD_COLOR )               &&
1623         !( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) &&
1624         map->pixel_mode == FT_PIXEL_MODE_BGRA         )
1625    {
1626      FT_Bitmap   new_map;
1627      FT_Library  library = face->root.glyph->library;
1628
1629
1630      FT_Bitmap_Init( &new_map );
1631
1632      /* Convert to 8bit grayscale. */
1633      error = FT_Bitmap_Convert( library, map, &new_map, 1 );
1634      if ( error )
1635        FT_Bitmap_Done( library, &new_map );
1636      else
1637      {
1638        map->pixel_mode = new_map.pixel_mode;
1639        map->pitch      = new_map.pitch;
1640        map->num_grays  = new_map.num_grays;
1641
1642        ft_glyphslot_set_bitmap( face->root.glyph, new_map.buffer );
1643        face->root.glyph->internal->flags |= FT_GLYPH_OWN_BITMAP;
1644      }
1645    }
1646
1647    return error;
1648  }
1649
1650
1651/* EOF */
1652