1 | /**************************************************************************** |
2 | * |
3 | * ttsbit.c |
4 | * |
5 | * TrueType and OpenType embedded bitmap support (body). |
6 | * |
7 | * Copyright (C) 2005-2019 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 | |
28 | |
29 | #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS |
30 | |
31 | #include "ttsbit.h" |
32 | |
33 | #include "sferrors.h" |
34 | |
35 | #include "ttmtx.h" |
36 | #include "pngshim.h" |
37 | |
38 | |
39 | /************************************************************************** |
40 | * |
41 | * The macro FT_COMPONENT is used in trace mode. It is an implicit |
42 | * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log |
43 | * messages during execution. |
44 | */ |
45 | #undef FT_COMPONENT |
46 | #define FT_COMPONENT ttsbit |
47 | |
48 | |
49 | FT_LOCAL_DEF( FT_Error ) |
50 | tt_face_load_sbit( TT_Face face, |
51 | FT_Stream stream ) |
52 | { |
53 | FT_Error error; |
54 | FT_ULong table_size; |
55 | FT_ULong table_start; |
56 | |
57 | |
58 | face->sbit_table = NULL; |
59 | face->sbit_table_size = 0; |
60 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_NONE; |
61 | face->sbit_num_strikes = 0; |
62 | |
63 | error = face->goto_table( face, TTAG_CBLC, stream, &table_size ); |
64 | if ( !error ) |
65 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_CBLC; |
66 | else |
67 | { |
68 | error = face->goto_table( face, TTAG_EBLC, stream, &table_size ); |
69 | if ( error ) |
70 | error = face->goto_table( face, TTAG_bloc, stream, &table_size ); |
71 | if ( !error ) |
72 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_EBLC; |
73 | } |
74 | |
75 | if ( error ) |
76 | { |
77 | error = face->goto_table( face, TTAG_sbix, stream, &table_size ); |
78 | if ( !error ) |
79 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_SBIX; |
80 | } |
81 | if ( error ) |
82 | goto Exit; |
83 | |
84 | if ( table_size < 8 ) |
85 | { |
86 | FT_ERROR(( "tt_face_load_sbit_strikes: table too short\n" )); |
87 | error = FT_THROW( Invalid_File_Format ); |
88 | goto Exit; |
89 | } |
90 | |
91 | table_start = FT_STREAM_POS(); |
92 | |
93 | switch ( (FT_UInt)face->sbit_table_type ) |
94 | { |
95 | case TT_SBIT_TABLE_TYPE_EBLC: |
96 | case TT_SBIT_TABLE_TYPE_CBLC: |
97 | { |
98 | FT_Byte* p; |
99 | FT_Fixed version; |
100 | FT_ULong num_strikes; |
101 | FT_UInt count; |
102 | |
103 | |
104 | if ( FT_FRAME_EXTRACT( table_size, face->sbit_table ) ) |
105 | goto Exit; |
106 | |
107 | face->sbit_table_size = table_size; |
108 | |
109 | p = face->sbit_table; |
110 | |
111 | version = FT_NEXT_LONG( p ); |
112 | num_strikes = FT_NEXT_ULONG( p ); |
113 | |
114 | /* there's at least one font (FZShuSong-Z01, version 3) */ |
115 | /* that uses the wrong byte order for the `version' field */ |
116 | if ( ( (FT_ULong)version & 0xFFFF0000UL ) != 0x00020000UL && |
117 | ( (FT_ULong)version & 0x0000FFFFUL ) != 0x00000200UL && |
118 | ( (FT_ULong)version & 0xFFFF0000UL ) != 0x00030000UL && |
119 | ( (FT_ULong)version & 0x0000FFFFUL ) != 0x00000300UL ) |
120 | { |
121 | error = FT_THROW( Unknown_File_Format ); |
122 | goto Exit; |
123 | } |
124 | |
125 | if ( num_strikes >= 0x10000UL ) |
126 | { |
127 | error = FT_THROW( Invalid_File_Format ); |
128 | goto Exit; |
129 | } |
130 | |
131 | /* |
132 | * Count the number of strikes available in the table. We are a bit |
133 | * paranoid there and don't trust the data. |
134 | */ |
135 | count = (FT_UInt)num_strikes; |
136 | if ( 8 + 48UL * count > table_size ) |
137 | count = (FT_UInt)( ( table_size - 8 ) / 48 ); |
138 | |
139 | face->sbit_num_strikes = count; |
140 | } |
141 | break; |
142 | |
143 | case TT_SBIT_TABLE_TYPE_SBIX: |
144 | { |
145 | FT_UShort version; |
146 | FT_UShort flags; |
147 | FT_ULong num_strikes; |
148 | FT_UInt count; |
149 | |
150 | |
151 | if ( FT_FRAME_ENTER( 8 ) ) |
152 | goto Exit; |
153 | |
154 | version = FT_GET_USHORT(); |
155 | flags = FT_GET_USHORT(); |
156 | num_strikes = FT_GET_ULONG(); |
157 | |
158 | FT_FRAME_EXIT(); |
159 | |
160 | if ( version < 1 ) |
161 | { |
162 | error = FT_THROW( Unknown_File_Format ); |
163 | goto Exit; |
164 | } |
165 | |
166 | /* Bit 0 must always be `1'. */ |
167 | /* Bit 1 controls the overlay of bitmaps with outlines. */ |
168 | /* All other bits should be zero. */ |
169 | if ( !( flags == 1 || flags == 3 ) || |
170 | num_strikes >= 0x10000UL ) |
171 | { |
172 | error = FT_THROW( Invalid_File_Format ); |
173 | goto Exit; |
174 | } |
175 | |
176 | /* we currently don't support bit 1; however, it is better to */ |
177 | /* draw at least something... */ |
178 | if ( flags == 3 ) |
179 | FT_TRACE1(( "tt_face_load_sbit_strikes:" |
180 | " sbix overlay not supported yet\n" |
181 | " " |
182 | " expect bad rendering results\n" )); |
183 | |
184 | /* |
185 | * Count the number of strikes available in the table. We are a bit |
186 | * paranoid there and don't trust the data. |
187 | */ |
188 | count = (FT_UInt)num_strikes; |
189 | if ( 8 + 4UL * count > table_size ) |
190 | count = (FT_UInt)( ( table_size - 8 ) / 4 ); |
191 | |
192 | if ( FT_STREAM_SEEK( FT_STREAM_POS() - 8 ) ) |
193 | goto Exit; |
194 | |
195 | face->sbit_table_size = 8 + count * 4; |
196 | if ( FT_FRAME_EXTRACT( face->sbit_table_size, face->sbit_table ) ) |
197 | goto Exit; |
198 | |
199 | face->sbit_num_strikes = count; |
200 | } |
201 | break; |
202 | |
203 | default: |
204 | /* we ignore unknown table formats */ |
205 | error = FT_THROW( Unknown_File_Format ); |
206 | break; |
207 | } |
208 | |
209 | if ( !error ) |
210 | FT_TRACE3(( "tt_face_load_sbit_strikes: found %u strikes\n" , |
211 | face->sbit_num_strikes )); |
212 | |
213 | face->ebdt_start = 0; |
214 | face->ebdt_size = 0; |
215 | |
216 | if ( face->sbit_table_type == TT_SBIT_TABLE_TYPE_SBIX ) |
217 | { |
218 | /* the `sbix' table is self-contained; */ |
219 | /* it has no associated data table */ |
220 | face->ebdt_start = table_start; |
221 | face->ebdt_size = table_size; |
222 | } |
223 | else if ( face->sbit_table_type != TT_SBIT_TABLE_TYPE_NONE ) |
224 | { |
225 | FT_ULong ebdt_size; |
226 | |
227 | |
228 | error = face->goto_table( face, TTAG_CBDT, stream, &ebdt_size ); |
229 | if ( error ) |
230 | error = face->goto_table( face, TTAG_EBDT, stream, &ebdt_size ); |
231 | if ( error ) |
232 | error = face->goto_table( face, TTAG_bdat, stream, &ebdt_size ); |
233 | |
234 | if ( !error ) |
235 | { |
236 | face->ebdt_start = FT_STREAM_POS(); |
237 | face->ebdt_size = ebdt_size; |
238 | } |
239 | } |
240 | |
241 | if ( !face->ebdt_size ) |
242 | { |
243 | FT_TRACE2(( "tt_face_load_sbit_strikes:" |
244 | " no embedded bitmap data table found;\n" |
245 | " " |
246 | " resetting number of strikes to zero\n" )); |
247 | face->sbit_num_strikes = 0; |
248 | } |
249 | |
250 | return FT_Err_Ok; |
251 | |
252 | Exit: |
253 | if ( error ) |
254 | { |
255 | if ( face->sbit_table ) |
256 | FT_FRAME_RELEASE( face->sbit_table ); |
257 | face->sbit_table_size = 0; |
258 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_NONE; |
259 | } |
260 | |
261 | return error; |
262 | } |
263 | |
264 | |
265 | FT_LOCAL_DEF( void ) |
266 | tt_face_free_sbit( TT_Face face ) |
267 | { |
268 | FT_Stream stream = face->root.stream; |
269 | |
270 | |
271 | FT_FRAME_RELEASE( face->sbit_table ); |
272 | face->sbit_table_size = 0; |
273 | face->sbit_table_type = TT_SBIT_TABLE_TYPE_NONE; |
274 | face->sbit_num_strikes = 0; |
275 | } |
276 | |
277 | |
278 | FT_LOCAL_DEF( FT_Error ) |
279 | tt_face_set_sbit_strike( TT_Face face, |
280 | FT_Size_Request req, |
281 | FT_ULong* astrike_index ) |
282 | { |
283 | return FT_Match_Size( (FT_Face)face, req, 0, astrike_index ); |
284 | } |
285 | |
286 | |
287 | FT_LOCAL_DEF( FT_Error ) |
288 | tt_face_load_strike_metrics( TT_Face face, |
289 | FT_ULong strike_index, |
290 | FT_Size_Metrics* metrics ) |
291 | { |
292 | /* we have to test for the existence of `sbit_strike_map' */ |
293 | /* because the function gets also used at the very beginning */ |
294 | /* to construct `sbit_strike_map' itself */ |
295 | if ( face->sbit_strike_map ) |
296 | { |
297 | if ( strike_index >= (FT_ULong)face->root.num_fixed_sizes ) |
298 | return FT_THROW( Invalid_Argument ); |
299 | |
300 | /* map to real index */ |
301 | strike_index = face->sbit_strike_map[strike_index]; |
302 | } |
303 | else |
304 | { |
305 | if ( strike_index >= (FT_ULong)face->sbit_num_strikes ) |
306 | return FT_THROW( Invalid_Argument ); |
307 | } |
308 | |
309 | switch ( (FT_UInt)face->sbit_table_type ) |
310 | { |
311 | case TT_SBIT_TABLE_TYPE_EBLC: |
312 | case TT_SBIT_TABLE_TYPE_CBLC: |
313 | { |
314 | FT_Byte* strike; |
315 | FT_Char max_before_bl; |
316 | FT_Char min_after_bl; |
317 | |
318 | |
319 | strike = face->sbit_table + 8 + strike_index * 48; |
320 | |
321 | metrics->x_ppem = (FT_UShort)strike[44]; |
322 | metrics->y_ppem = (FT_UShort)strike[45]; |
323 | |
324 | metrics->ascender = (FT_Char)strike[16] * 64; /* hori.ascender */ |
325 | metrics->descender = (FT_Char)strike[17] * 64; /* hori.descender */ |
326 | |
327 | /* Due to fuzzy wording in the EBLC documentation, we find both */ |
328 | /* positive and negative values for `descender'. Additionally, */ |
329 | /* many fonts have both `ascender' and `descender' set to zero */ |
330 | /* (which is definitely wrong). MS Windows simply ignores all */ |
331 | /* those values... For these reasons we apply some heuristics */ |
332 | /* to get a reasonable, non-zero value for the height. */ |
333 | |
334 | max_before_bl = (FT_Char)strike[24]; |
335 | min_after_bl = (FT_Char)strike[25]; |
336 | |
337 | if ( metrics->descender > 0 ) |
338 | { |
339 | /* compare sign of descender with `min_after_bl' */ |
340 | if ( min_after_bl < 0 ) |
341 | metrics->descender = -metrics->descender; |
342 | } |
343 | |
344 | else if ( metrics->descender == 0 ) |
345 | { |
346 | if ( metrics->ascender == 0 ) |
347 | { |
348 | FT_TRACE2(( "tt_face_load_strike_metrics:" |
349 | " sanitizing invalid ascender and descender\n" |
350 | " " |
351 | " values for strike %d (%dppem, %dppem)\n" , |
352 | strike_index, |
353 | metrics->x_ppem, metrics->y_ppem )); |
354 | |
355 | /* sanitize buggy ascender and descender values */ |
356 | if ( max_before_bl || min_after_bl ) |
357 | { |
358 | metrics->ascender = max_before_bl * 64; |
359 | metrics->descender = min_after_bl * 64; |
360 | } |
361 | else |
362 | { |
363 | metrics->ascender = metrics->y_ppem * 64; |
364 | metrics->descender = 0; |
365 | } |
366 | } |
367 | } |
368 | |
369 | #if 0 |
370 | else |
371 | ; /* if we have a negative descender, simply use it */ |
372 | #endif |
373 | |
374 | metrics->height = metrics->ascender - metrics->descender; |
375 | if ( metrics->height == 0 ) |
376 | { |
377 | FT_TRACE2(( "tt_face_load_strike_metrics:" |
378 | " sanitizing invalid height value\n" |
379 | " " |
380 | " for strike (%d, %d)\n" , |
381 | metrics->x_ppem, metrics->y_ppem )); |
382 | metrics->height = metrics->y_ppem * 64; |
383 | metrics->descender = metrics->ascender - metrics->height; |
384 | } |
385 | |
386 | /* Is this correct? */ |
387 | metrics->max_advance = ( (FT_Char)strike[22] + /* min_origin_SB */ |
388 | strike[18] + /* max_width */ |
389 | (FT_Char)strike[23] /* min_advance_SB */ |
390 | ) * 64; |
391 | |
392 | /* set the scale values (in 16.16 units) so advances */ |
393 | /* from the hmtx and vmtx table are scaled correctly */ |
394 | metrics->x_scale = FT_MulDiv( metrics->x_ppem, |
395 | 64 * 0x10000, |
396 | face->header.Units_Per_EM ); |
397 | metrics->y_scale = FT_MulDiv( metrics->y_ppem, |
398 | 64 * 0x10000, |
399 | face->header.Units_Per_EM ); |
400 | |
401 | return FT_Err_Ok; |
402 | } |
403 | |
404 | case TT_SBIT_TABLE_TYPE_SBIX: |
405 | { |
406 | FT_Stream stream = face->root.stream; |
407 | FT_UInt offset; |
408 | FT_UShort upem, ppem, resolution; |
409 | TT_HoriHeader *hori; |
410 | FT_Pos ppem_; /* to reduce casts */ |
411 | |
412 | FT_Error error; |
413 | FT_Byte* p; |
414 | |
415 | |
416 | p = face->sbit_table + 8 + 4 * strike_index; |
417 | offset = FT_NEXT_ULONG( p ); |
418 | |
419 | if ( offset + 4 > face->ebdt_size ) |
420 | return FT_THROW( Invalid_File_Format ); |
421 | |
422 | if ( FT_STREAM_SEEK( face->ebdt_start + offset ) || |
423 | FT_FRAME_ENTER( 4 ) ) |
424 | return error; |
425 | |
426 | ppem = FT_GET_USHORT(); |
427 | resolution = FT_GET_USHORT(); |
428 | |
429 | FT_UNUSED( resolution ); /* What to do with this? */ |
430 | |
431 | FT_FRAME_EXIT(); |
432 | |
433 | upem = face->header.Units_Per_EM; |
434 | hori = &face->horizontal; |
435 | |
436 | metrics->x_ppem = ppem; |
437 | metrics->y_ppem = ppem; |
438 | |
439 | ppem_ = (FT_Pos)ppem; |
440 | |
441 | metrics->ascender = |
442 | FT_MulDiv( hori->Ascender, ppem_ * 64, upem ); |
443 | metrics->descender = |
444 | FT_MulDiv( hori->Descender, ppem_ * 64, upem ); |
445 | metrics->height = |
446 | FT_MulDiv( hori->Ascender - hori->Descender + hori->Line_Gap, |
447 | ppem_ * 64, upem ); |
448 | metrics->max_advance = |
449 | FT_MulDiv( hori->advance_Width_Max, ppem_ * 64, upem ); |
450 | |
451 | /* set the scale values (in 16.16 units) so advances */ |
452 | /* from the hmtx and vmtx table are scaled correctly */ |
453 | metrics->x_scale = FT_MulDiv( metrics->x_ppem, |
454 | 64 * 0x10000, |
455 | face->header.Units_Per_EM ); |
456 | metrics->y_scale = FT_MulDiv( metrics->y_ppem, |
457 | 64 * 0x10000, |
458 | face->header.Units_Per_EM ); |
459 | |
460 | return error; |
461 | } |
462 | |
463 | default: |
464 | return FT_THROW( Unknown_File_Format ); |
465 | } |
466 | } |
467 | |
468 | |
469 | typedef struct TT_SBitDecoderRec_ |
470 | { |
471 | TT_Face face; |
472 | FT_Stream stream; |
473 | FT_Bitmap* bitmap; |
474 | TT_SBit_Metrics metrics; |
475 | FT_Bool metrics_loaded; |
476 | FT_Bool bitmap_allocated; |
477 | FT_Byte bit_depth; |
478 | |
479 | FT_ULong ebdt_start; |
480 | FT_ULong ebdt_size; |
481 | |
482 | FT_ULong strike_index_array; |
483 | FT_ULong strike_index_count; |
484 | FT_Byte* eblc_base; |
485 | FT_Byte* eblc_limit; |
486 | |
487 | } TT_SBitDecoderRec, *TT_SBitDecoder; |
488 | |
489 | |
490 | static FT_Error |
491 | tt_sbit_decoder_init( TT_SBitDecoder decoder, |
492 | TT_Face face, |
493 | FT_ULong strike_index, |
494 | TT_SBit_MetricsRec* metrics ) |
495 | { |
496 | FT_Error error = FT_ERR( Table_Missing ); |
497 | FT_Stream stream = face->root.stream; |
498 | |
499 | |
500 | strike_index = face->sbit_strike_map[strike_index]; |
501 | |
502 | if ( !face->ebdt_size ) |
503 | goto Exit; |
504 | if ( FT_STREAM_SEEK( face->ebdt_start ) ) |
505 | goto Exit; |
506 | |
507 | decoder->face = face; |
508 | decoder->stream = stream; |
509 | decoder->bitmap = &face->root.glyph->bitmap; |
510 | decoder->metrics = metrics; |
511 | |
512 | decoder->metrics_loaded = 0; |
513 | decoder->bitmap_allocated = 0; |
514 | |
515 | decoder->ebdt_start = face->ebdt_start; |
516 | decoder->ebdt_size = face->ebdt_size; |
517 | |
518 | decoder->eblc_base = face->sbit_table; |
519 | decoder->eblc_limit = face->sbit_table + face->sbit_table_size; |
520 | |
521 | /* now find the strike corresponding to the index */ |
522 | { |
523 | FT_Byte* p; |
524 | |
525 | |
526 | if ( 8 + 48 * strike_index + 3 * 4 + 34 + 1 > face->sbit_table_size ) |
527 | { |
528 | error = FT_THROW( Invalid_File_Format ); |
529 | goto Exit; |
530 | } |
531 | |
532 | p = decoder->eblc_base + 8 + 48 * strike_index; |
533 | |
534 | decoder->strike_index_array = FT_NEXT_ULONG( p ); |
535 | p += 4; |
536 | decoder->strike_index_count = FT_NEXT_ULONG( p ); |
537 | p += 34; |
538 | decoder->bit_depth = *p; |
539 | |
540 | /* decoder->strike_index_array + */ |
541 | /* 8 * decoder->strike_index_count > face->sbit_table_size ? */ |
542 | if ( decoder->strike_index_array > face->sbit_table_size || |
543 | decoder->strike_index_count > |
544 | ( face->sbit_table_size - decoder->strike_index_array ) / 8 ) |
545 | error = FT_THROW( Invalid_File_Format ); |
546 | } |
547 | |
548 | Exit: |
549 | return error; |
550 | } |
551 | |
552 | |
553 | static void |
554 | tt_sbit_decoder_done( TT_SBitDecoder decoder ) |
555 | { |
556 | FT_UNUSED( decoder ); |
557 | } |
558 | |
559 | |
560 | static FT_Error |
561 | tt_sbit_decoder_alloc_bitmap( TT_SBitDecoder decoder, |
562 | FT_Bool metrics_only ) |
563 | { |
564 | FT_Error error = FT_Err_Ok; |
565 | FT_UInt width, height; |
566 | FT_Bitmap* map = decoder->bitmap; |
567 | FT_ULong size; |
568 | |
569 | |
570 | if ( !decoder->metrics_loaded ) |
571 | { |
572 | error = FT_THROW( Invalid_Argument ); |
573 | goto Exit; |
574 | } |
575 | |
576 | width = decoder->metrics->width; |
577 | height = decoder->metrics->height; |
578 | |
579 | map->width = width; |
580 | map->rows = height; |
581 | |
582 | switch ( decoder->bit_depth ) |
583 | { |
584 | case 1: |
585 | map->pixel_mode = FT_PIXEL_MODE_MONO; |
586 | map->pitch = (int)( ( map->width + 7 ) >> 3 ); |
587 | map->num_grays = 2; |
588 | break; |
589 | |
590 | case 2: |
591 | map->pixel_mode = FT_PIXEL_MODE_GRAY2; |
592 | map->pitch = (int)( ( map->width + 3 ) >> 2 ); |
593 | map->num_grays = 4; |
594 | break; |
595 | |
596 | case 4: |
597 | map->pixel_mode = FT_PIXEL_MODE_GRAY4; |
598 | map->pitch = (int)( ( map->width + 1 ) >> 1 ); |
599 | map->num_grays = 16; |
600 | break; |
601 | |
602 | case 8: |
603 | map->pixel_mode = FT_PIXEL_MODE_GRAY; |
604 | map->pitch = (int)( map->width ); |
605 | map->num_grays = 256; |
606 | break; |
607 | |
608 | case 32: |
609 | map->pixel_mode = FT_PIXEL_MODE_BGRA; |
610 | map->pitch = (int)( map->width * 4 ); |
611 | map->num_grays = 256; |
612 | break; |
613 | |
614 | default: |
615 | error = FT_THROW( Invalid_File_Format ); |
616 | goto Exit; |
617 | } |
618 | |
619 | size = map->rows * (FT_ULong)map->pitch; |
620 | |
621 | /* check that there is no empty image */ |
622 | if ( size == 0 ) |
623 | goto Exit; /* exit successfully! */ |
624 | |
625 | if ( metrics_only ) |
626 | goto Exit; /* only metrics are requested */ |
627 | |
628 | error = ft_glyphslot_alloc_bitmap( decoder->face->root.glyph, size ); |
629 | if ( error ) |
630 | goto Exit; |
631 | |
632 | decoder->bitmap_allocated = 1; |
633 | |
634 | Exit: |
635 | return error; |
636 | } |
637 | |
638 | |
639 | static FT_Error |
640 | tt_sbit_decoder_load_metrics( TT_SBitDecoder decoder, |
641 | FT_Byte* *pp, |
642 | FT_Byte* limit, |
643 | FT_Bool big ) |
644 | { |
645 | FT_Byte* p = *pp; |
646 | TT_SBit_Metrics metrics = decoder->metrics; |
647 | |
648 | |
649 | if ( p + 5 > limit ) |
650 | goto Fail; |
651 | |
652 | metrics->height = p[0]; |
653 | metrics->width = p[1]; |
654 | metrics->horiBearingX = (FT_Char)p[2]; |
655 | metrics->horiBearingY = (FT_Char)p[3]; |
656 | metrics->horiAdvance = p[4]; |
657 | |
658 | p += 5; |
659 | if ( big ) |
660 | { |
661 | if ( p + 3 > limit ) |
662 | goto Fail; |
663 | |
664 | metrics->vertBearingX = (FT_Char)p[0]; |
665 | metrics->vertBearingY = (FT_Char)p[1]; |
666 | metrics->vertAdvance = p[2]; |
667 | |
668 | p += 3; |
669 | } |
670 | else |
671 | { |
672 | /* avoid uninitialized data in case there is no vertical info -- */ |
673 | metrics->vertBearingX = 0; |
674 | metrics->vertBearingY = 0; |
675 | metrics->vertAdvance = 0; |
676 | } |
677 | |
678 | decoder->metrics_loaded = 1; |
679 | *pp = p; |
680 | return FT_Err_Ok; |
681 | |
682 | Fail: |
683 | FT_TRACE1(( "tt_sbit_decoder_load_metrics: broken table\n" )); |
684 | return FT_THROW( Invalid_Argument ); |
685 | } |
686 | |
687 | |
688 | /* forward declaration */ |
689 | static FT_Error |
690 | tt_sbit_decoder_load_image( TT_SBitDecoder decoder, |
691 | FT_UInt glyph_index, |
692 | FT_Int x_pos, |
693 | FT_Int y_pos, |
694 | FT_UInt recurse_count, |
695 | FT_Bool metrics_only ); |
696 | |
697 | typedef FT_Error (*TT_SBitDecoder_LoadFunc)( |
698 | TT_SBitDecoder decoder, |
699 | FT_Byte* p, |
700 | FT_Byte* plimit, |
701 | FT_Int x_pos, |
702 | FT_Int y_pos, |
703 | FT_UInt recurse_count ); |
704 | |
705 | |
706 | static FT_Error |
707 | tt_sbit_decoder_load_byte_aligned( TT_SBitDecoder decoder, |
708 | FT_Byte* p, |
709 | FT_Byte* limit, |
710 | FT_Int x_pos, |
711 | FT_Int y_pos, |
712 | FT_UInt recurse_count ) |
713 | { |
714 | FT_Error error = FT_Err_Ok; |
715 | FT_Byte* line; |
716 | FT_Int pitch, width, height, line_bits, h; |
717 | FT_UInt bit_height, bit_width; |
718 | FT_Bitmap* bitmap; |
719 | |
720 | FT_UNUSED( recurse_count ); |
721 | |
722 | |
723 | /* check that we can write the glyph into the bitmap */ |
724 | bitmap = decoder->bitmap; |
725 | bit_width = bitmap->width; |
726 | bit_height = bitmap->rows; |
727 | pitch = bitmap->pitch; |
728 | line = bitmap->buffer; |
729 | |
730 | width = decoder->metrics->width; |
731 | height = decoder->metrics->height; |
732 | |
733 | line_bits = width * decoder->bit_depth; |
734 | |
735 | if ( x_pos < 0 || (FT_UInt)( x_pos + width ) > bit_width || |
736 | y_pos < 0 || (FT_UInt)( y_pos + height ) > bit_height ) |
737 | { |
738 | FT_TRACE1(( "tt_sbit_decoder_load_byte_aligned:" |
739 | " invalid bitmap dimensions\n" )); |
740 | error = FT_THROW( Invalid_File_Format ); |
741 | goto Exit; |
742 | } |
743 | |
744 | if ( p + ( ( line_bits + 7 ) >> 3 ) * height > limit ) |
745 | { |
746 | FT_TRACE1(( "tt_sbit_decoder_load_byte_aligned: broken bitmap\n" )); |
747 | error = FT_THROW( Invalid_File_Format ); |
748 | goto Exit; |
749 | } |
750 | |
751 | /* now do the blit */ |
752 | line += y_pos * pitch + ( x_pos >> 3 ); |
753 | x_pos &= 7; |
754 | |
755 | if ( x_pos == 0 ) /* the easy one */ |
756 | { |
757 | for ( h = height; h > 0; h--, line += pitch ) |
758 | { |
759 | FT_Byte* pwrite = line; |
760 | FT_Int w; |
761 | |
762 | |
763 | for ( w = line_bits; w >= 8; w -= 8 ) |
764 | { |
765 | pwrite[0] = (FT_Byte)( pwrite[0] | *p++ ); |
766 | pwrite += 1; |
767 | } |
768 | |
769 | if ( w > 0 ) |
770 | pwrite[0] = (FT_Byte)( pwrite[0] | ( *p++ & ( 0xFF00U >> w ) ) ); |
771 | } |
772 | } |
773 | else /* x_pos > 0 */ |
774 | { |
775 | for ( h = height; h > 0; h--, line += pitch ) |
776 | { |
777 | FT_Byte* pwrite = line; |
778 | FT_Int w; |
779 | FT_UInt wval = 0; |
780 | |
781 | |
782 | for ( w = line_bits; w >= 8; w -= 8 ) |
783 | { |
784 | wval = (FT_UInt)( wval | *p++ ); |
785 | pwrite[0] = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) ); |
786 | pwrite += 1; |
787 | wval <<= 8; |
788 | } |
789 | |
790 | if ( w > 0 ) |
791 | wval = (FT_UInt)( wval | ( *p++ & ( 0xFF00U >> w ) ) ); |
792 | |
793 | /* all bits read and there are `x_pos + w' bits to be written */ |
794 | |
795 | pwrite[0] = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) ); |
796 | |
797 | if ( x_pos + w > 8 ) |
798 | { |
799 | pwrite++; |
800 | wval <<= 8; |
801 | pwrite[0] = (FT_Byte)( pwrite[0] | ( wval >> x_pos ) ); |
802 | } |
803 | } |
804 | } |
805 | |
806 | Exit: |
807 | if ( !error ) |
808 | FT_TRACE3(( "tt_sbit_decoder_load_byte_aligned: loaded\n" )); |
809 | return error; |
810 | } |
811 | |
812 | |
813 | /* |
814 | * Load a bit-aligned bitmap (with pointer `p') into a line-aligned bitmap |
815 | * (with pointer `pwrite'). In the example below, the width is 3 pixel, |
816 | * and `x_pos' is 1 pixel. |
817 | * |
818 | * p p+1 |
819 | * | | | |
820 | * | 7 6 5 4 3 2 1 0 | 7 6 5 4 3 2 1 0 |... |
821 | * | | | |
822 | * +-------+ +-------+ +-------+ ... |
823 | * . . . |
824 | * . . . |
825 | * v . . |
826 | * +-------+ . . |
827 | * | | . |
828 | * | 7 6 5 4 3 2 1 0 | . |
829 | * | | . |
830 | * pwrite . . |
831 | * . . |
832 | * v . |
833 | * +-------+ . |
834 | * | | |
835 | * | 7 6 5 4 3 2 1 0 | |
836 | * | | |
837 | * pwrite+1 . |
838 | * . |
839 | * v |
840 | * +-------+ |
841 | * | | |
842 | * | 7 6 5 4 3 2 1 0 | |
843 | * | | |
844 | * pwrite+2 |
845 | * |
846 | */ |
847 | |
848 | static FT_Error |
849 | tt_sbit_decoder_load_bit_aligned( TT_SBitDecoder decoder, |
850 | FT_Byte* p, |
851 | FT_Byte* limit, |
852 | FT_Int x_pos, |
853 | FT_Int y_pos, |
854 | FT_UInt recurse_count ) |
855 | { |
856 | FT_Error error = FT_Err_Ok; |
857 | FT_Byte* line; |
858 | FT_Int pitch, width, height, line_bits, h, nbits; |
859 | FT_UInt bit_height, bit_width; |
860 | FT_Bitmap* bitmap; |
861 | FT_UShort rval; |
862 | |
863 | FT_UNUSED( recurse_count ); |
864 | |
865 | |
866 | /* check that we can write the glyph into the bitmap */ |
867 | bitmap = decoder->bitmap; |
868 | bit_width = bitmap->width; |
869 | bit_height = bitmap->rows; |
870 | pitch = bitmap->pitch; |
871 | line = bitmap->buffer; |
872 | |
873 | width = decoder->metrics->width; |
874 | height = decoder->metrics->height; |
875 | |
876 | line_bits = width * decoder->bit_depth; |
877 | |
878 | if ( x_pos < 0 || (FT_UInt)( x_pos + width ) > bit_width || |
879 | y_pos < 0 || (FT_UInt)( y_pos + height ) > bit_height ) |
880 | { |
881 | FT_TRACE1(( "tt_sbit_decoder_load_bit_aligned:" |
882 | " invalid bitmap dimensions\n" )); |
883 | error = FT_THROW( Invalid_File_Format ); |
884 | goto Exit; |
885 | } |
886 | |
887 | if ( p + ( ( line_bits * height + 7 ) >> 3 ) > limit ) |
888 | { |
889 | FT_TRACE1(( "tt_sbit_decoder_load_bit_aligned: broken bitmap\n" )); |
890 | error = FT_THROW( Invalid_File_Format ); |
891 | goto Exit; |
892 | } |
893 | |
894 | if ( !line_bits || !height ) |
895 | { |
896 | /* nothing to do */ |
897 | goto Exit; |
898 | } |
899 | |
900 | /* now do the blit */ |
901 | |
902 | /* adjust `line' to point to the first byte of the bitmap */ |
903 | line += y_pos * pitch + ( x_pos >> 3 ); |
904 | x_pos &= 7; |
905 | |
906 | /* the higher byte of `rval' is used as a buffer */ |
907 | rval = 0; |
908 | nbits = 0; |
909 | |
910 | for ( h = height; h > 0; h--, line += pitch ) |
911 | { |
912 | FT_Byte* pwrite = line; |
913 | FT_Int w = line_bits; |
914 | |
915 | |
916 | /* handle initial byte (in target bitmap) specially if necessary */ |
917 | if ( x_pos ) |
918 | { |
919 | w = ( line_bits < 8 - x_pos ) ? line_bits : 8 - x_pos; |
920 | |
921 | if ( h == height ) |
922 | { |
923 | rval = *p++; |
924 | nbits = x_pos; |
925 | } |
926 | else if ( nbits < w ) |
927 | { |
928 | if ( p < limit ) |
929 | rval |= *p++; |
930 | nbits += 8 - w; |
931 | } |
932 | else |
933 | { |
934 | rval >>= 8; |
935 | nbits -= w; |
936 | } |
937 | |
938 | *pwrite++ |= ( ( rval >> nbits ) & 0xFF ) & |
939 | ( ~( 0xFFU << w ) << ( 8 - w - x_pos ) ); |
940 | rval <<= 8; |
941 | |
942 | w = line_bits - w; |
943 | } |
944 | |
945 | /* handle medial bytes */ |
946 | for ( ; w >= 8; w -= 8 ) |
947 | { |
948 | rval |= *p++; |
949 | *pwrite++ |= ( rval >> nbits ) & 0xFF; |
950 | |
951 | rval <<= 8; |
952 | } |
953 | |
954 | /* handle final byte if necessary */ |
955 | if ( w > 0 ) |
956 | { |
957 | if ( nbits < w ) |
958 | { |
959 | if ( p < limit ) |
960 | rval |= *p++; |
961 | *pwrite |= ( ( rval >> nbits ) & 0xFF ) & ( 0xFF00U >> w ); |
962 | nbits += 8 - w; |
963 | |
964 | rval <<= 8; |
965 | } |
966 | else |
967 | { |
968 | *pwrite |= ( ( rval >> nbits ) & 0xFF ) & ( 0xFF00U >> w ); |
969 | nbits -= w; |
970 | } |
971 | } |
972 | } |
973 | |
974 | Exit: |
975 | if ( !error ) |
976 | FT_TRACE3(( "tt_sbit_decoder_load_bit_aligned: loaded\n" )); |
977 | return error; |
978 | } |
979 | |
980 | |
981 | static FT_Error |
982 | tt_sbit_decoder_load_compound( TT_SBitDecoder decoder, |
983 | FT_Byte* p, |
984 | FT_Byte* limit, |
985 | FT_Int x_pos, |
986 | FT_Int y_pos, |
987 | FT_UInt recurse_count ) |
988 | { |
989 | FT_Error error = FT_Err_Ok; |
990 | FT_UInt num_components, nn; |
991 | |
992 | FT_Char horiBearingX = (FT_Char)decoder->metrics->horiBearingX; |
993 | FT_Char horiBearingY = (FT_Char)decoder->metrics->horiBearingY; |
994 | FT_Byte horiAdvance = (FT_Byte)decoder->metrics->horiAdvance; |
995 | FT_Char vertBearingX = (FT_Char)decoder->metrics->vertBearingX; |
996 | FT_Char vertBearingY = (FT_Char)decoder->metrics->vertBearingY; |
997 | FT_Byte vertAdvance = (FT_Byte)decoder->metrics->vertAdvance; |
998 | |
999 | |
1000 | if ( p + 2 > limit ) |
1001 | goto Fail; |
1002 | |
1003 | num_components = FT_NEXT_USHORT( p ); |
1004 | if ( p + 4 * num_components > limit ) |
1005 | { |
1006 | FT_TRACE1(( "tt_sbit_decoder_load_compound: broken table\n" )); |
1007 | goto Fail; |
1008 | } |
1009 | |
1010 | FT_TRACE3(( "tt_sbit_decoder_load_compound: loading %d component%s\n" , |
1011 | num_components, |
1012 | num_components == 1 ? "" : "s" )); |
1013 | |
1014 | for ( nn = 0; nn < num_components; nn++ ) |
1015 | { |
1016 | FT_UInt gindex = FT_NEXT_USHORT( p ); |
1017 | FT_Char dx = FT_NEXT_CHAR( p ); |
1018 | FT_Char dy = FT_NEXT_CHAR( p ); |
1019 | |
1020 | |
1021 | /* NB: a recursive call */ |
1022 | error = tt_sbit_decoder_load_image( decoder, |
1023 | gindex, |
1024 | x_pos + dx, |
1025 | y_pos + dy, |
1026 | recurse_count + 1, |
1027 | /* request full bitmap image */ |
1028 | FALSE ); |
1029 | if ( error ) |
1030 | break; |
1031 | } |
1032 | |
1033 | FT_TRACE3(( "tt_sbit_decoder_load_compound: done\n" )); |
1034 | |
1035 | decoder->metrics->horiBearingX = horiBearingX; |
1036 | decoder->metrics->horiBearingY = horiBearingY; |
1037 | decoder->metrics->horiAdvance = horiAdvance; |
1038 | decoder->metrics->vertBearingX = vertBearingX; |
1039 | decoder->metrics->vertBearingY = vertBearingY; |
1040 | decoder->metrics->vertAdvance = vertAdvance; |
1041 | decoder->metrics->width = (FT_Byte)decoder->bitmap->width; |
1042 | decoder->metrics->height = (FT_Byte)decoder->bitmap->rows; |
1043 | |
1044 | Exit: |
1045 | return error; |
1046 | |
1047 | Fail: |
1048 | error = FT_THROW( Invalid_File_Format ); |
1049 | goto Exit; |
1050 | } |
1051 | |
1052 | |
1053 | #ifdef FT_CONFIG_OPTION_USE_PNG |
1054 | |
1055 | static FT_Error |
1056 | tt_sbit_decoder_load_png( TT_SBitDecoder decoder, |
1057 | FT_Byte* p, |
1058 | FT_Byte* limit, |
1059 | FT_Int x_pos, |
1060 | FT_Int y_pos, |
1061 | FT_UInt recurse_count ) |
1062 | { |
1063 | FT_Error error = FT_Err_Ok; |
1064 | FT_ULong png_len; |
1065 | |
1066 | FT_UNUSED( recurse_count ); |
1067 | |
1068 | |
1069 | if ( limit - p < 4 ) |
1070 | { |
1071 | FT_TRACE1(( "tt_sbit_decoder_load_png: broken bitmap\n" )); |
1072 | error = FT_THROW( Invalid_File_Format ); |
1073 | goto Exit; |
1074 | } |
1075 | |
1076 | png_len = FT_NEXT_ULONG( p ); |
1077 | if ( (FT_ULong)( limit - p ) < png_len ) |
1078 | { |
1079 | FT_TRACE1(( "tt_sbit_decoder_load_png: broken bitmap\n" )); |
1080 | error = FT_THROW( Invalid_File_Format ); |
1081 | goto Exit; |
1082 | } |
1083 | |
1084 | error = Load_SBit_Png( decoder->face->root.glyph, |
1085 | x_pos, |
1086 | y_pos, |
1087 | decoder->bit_depth, |
1088 | decoder->metrics, |
1089 | decoder->stream->memory, |
1090 | p, |
1091 | png_len, |
1092 | FALSE, |
1093 | FALSE ); |
1094 | |
1095 | Exit: |
1096 | if ( !error ) |
1097 | FT_TRACE3(( "tt_sbit_decoder_load_png: loaded\n" )); |
1098 | return error; |
1099 | } |
1100 | |
1101 | #endif /* FT_CONFIG_OPTION_USE_PNG */ |
1102 | |
1103 | |
1104 | static FT_Error |
1105 | tt_sbit_decoder_load_bitmap( TT_SBitDecoder decoder, |
1106 | FT_UInt glyph_format, |
1107 | FT_ULong glyph_start, |
1108 | FT_ULong glyph_size, |
1109 | FT_Int x_pos, |
1110 | FT_Int y_pos, |
1111 | FT_UInt recurse_count, |
1112 | FT_Bool metrics_only ) |
1113 | { |
1114 | FT_Error error; |
1115 | FT_Stream stream = decoder->stream; |
1116 | FT_Byte* p; |
1117 | FT_Byte* p_limit; |
1118 | FT_Byte* data; |
1119 | |
1120 | |
1121 | /* seek into the EBDT table now */ |
1122 | if ( !glyph_size || |
1123 | glyph_start + glyph_size > decoder->ebdt_size ) |
1124 | { |
1125 | error = FT_THROW( Invalid_Argument ); |
1126 | goto Exit; |
1127 | } |
1128 | |
1129 | if ( FT_STREAM_SEEK( decoder->ebdt_start + glyph_start ) || |
1130 | FT_FRAME_EXTRACT( glyph_size, data ) ) |
1131 | goto Exit; |
1132 | |
1133 | p = data; |
1134 | p_limit = p + glyph_size; |
1135 | |
1136 | /* read the data, depending on the glyph format */ |
1137 | switch ( glyph_format ) |
1138 | { |
1139 | case 1: |
1140 | case 2: |
1141 | case 8: |
1142 | case 17: |
1143 | error = tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 0 ); |
1144 | break; |
1145 | |
1146 | case 6: |
1147 | case 7: |
1148 | case 9: |
1149 | case 18: |
1150 | error = tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 ); |
1151 | break; |
1152 | |
1153 | default: |
1154 | error = FT_Err_Ok; |
1155 | } |
1156 | |
1157 | if ( error ) |
1158 | goto Fail; |
1159 | |
1160 | { |
1161 | TT_SBitDecoder_LoadFunc loader; |
1162 | |
1163 | |
1164 | switch ( glyph_format ) |
1165 | { |
1166 | case 1: |
1167 | case 6: |
1168 | loader = tt_sbit_decoder_load_byte_aligned; |
1169 | break; |
1170 | |
1171 | case 2: |
1172 | case 7: |
1173 | { |
1174 | /* Don't trust `glyph_format'. For example, Apple's main Korean */ |
1175 | /* system font, `AppleMyungJo.ttf' (version 7.0d2e6), uses glyph */ |
1176 | /* format 7, but the data is format 6. We check whether we have */ |
1177 | /* an excessive number of bytes in the image: If it is equal to */ |
1178 | /* the value for a byte-aligned glyph, use the other loading */ |
1179 | /* routine. */ |
1180 | /* */ |
1181 | /* Note that for some (width,height) combinations, where the */ |
1182 | /* width is not a multiple of 8, the sizes for bit- and */ |
1183 | /* byte-aligned data are equal, for example (7,7) or (15,6). We */ |
1184 | /* then prefer what `glyph_format' specifies. */ |
1185 | |
1186 | FT_UInt width = decoder->metrics->width; |
1187 | FT_UInt height = decoder->metrics->height; |
1188 | |
1189 | FT_UInt bit_size = ( width * height + 7 ) >> 3; |
1190 | FT_UInt byte_size = height * ( ( width + 7 ) >> 3 ); |
1191 | |
1192 | |
1193 | if ( bit_size < byte_size && |
1194 | byte_size == (FT_UInt)( p_limit - p ) ) |
1195 | loader = tt_sbit_decoder_load_byte_aligned; |
1196 | else |
1197 | loader = tt_sbit_decoder_load_bit_aligned; |
1198 | } |
1199 | break; |
1200 | |
1201 | case 5: |
1202 | loader = tt_sbit_decoder_load_bit_aligned; |
1203 | break; |
1204 | |
1205 | case 8: |
1206 | if ( p + 1 > p_limit ) |
1207 | goto Fail; |
1208 | |
1209 | p += 1; /* skip padding */ |
1210 | /* fall-through */ |
1211 | |
1212 | case 9: |
1213 | loader = tt_sbit_decoder_load_compound; |
1214 | break; |
1215 | |
1216 | case 17: /* small metrics, PNG image data */ |
1217 | case 18: /* big metrics, PNG image data */ |
1218 | case 19: /* metrics in EBLC, PNG image data */ |
1219 | #ifdef FT_CONFIG_OPTION_USE_PNG |
1220 | loader = tt_sbit_decoder_load_png; |
1221 | break; |
1222 | #else |
1223 | error = FT_THROW( Unimplemented_Feature ); |
1224 | goto Fail; |
1225 | #endif /* FT_CONFIG_OPTION_USE_PNG */ |
1226 | |
1227 | default: |
1228 | error = FT_THROW( Invalid_Table ); |
1229 | goto Fail; |
1230 | } |
1231 | |
1232 | if ( !decoder->bitmap_allocated ) |
1233 | { |
1234 | error = tt_sbit_decoder_alloc_bitmap( decoder, metrics_only ); |
1235 | |
1236 | if ( error ) |
1237 | goto Fail; |
1238 | } |
1239 | |
1240 | if ( metrics_only ) |
1241 | goto Fail; /* this is not an error */ |
1242 | |
1243 | error = loader( decoder, p, p_limit, x_pos, y_pos, recurse_count ); |
1244 | } |
1245 | |
1246 | Fail: |
1247 | FT_FRAME_RELEASE( data ); |
1248 | |
1249 | Exit: |
1250 | return error; |
1251 | } |
1252 | |
1253 | |
1254 | static FT_Error |
1255 | tt_sbit_decoder_load_image( TT_SBitDecoder decoder, |
1256 | FT_UInt glyph_index, |
1257 | FT_Int x_pos, |
1258 | FT_Int y_pos, |
1259 | FT_UInt recurse_count, |
1260 | FT_Bool metrics_only ) |
1261 | { |
1262 | FT_Byte* p = decoder->eblc_base + decoder->strike_index_array; |
1263 | FT_Byte* p_limit = decoder->eblc_limit; |
1264 | FT_ULong num_ranges = decoder->strike_index_count; |
1265 | FT_UInt start, end, index_format, image_format; |
1266 | FT_ULong image_start = 0, image_end = 0, image_offset; |
1267 | |
1268 | |
1269 | /* arbitrary recursion limit */ |
1270 | if ( recurse_count > 100 ) |
1271 | { |
1272 | FT_TRACE4(( "tt_sbit_decoder_load_image:" |
1273 | " recursion depth exceeded\n" )); |
1274 | goto Failure; |
1275 | } |
1276 | |
1277 | |
1278 | /* First, we find the correct strike range that applies to this */ |
1279 | /* glyph index. */ |
1280 | for ( ; num_ranges > 0; num_ranges-- ) |
1281 | { |
1282 | start = FT_NEXT_USHORT( p ); |
1283 | end = FT_NEXT_USHORT( p ); |
1284 | |
1285 | if ( glyph_index >= start && glyph_index <= end ) |
1286 | goto FoundRange; |
1287 | |
1288 | p += 4; /* ignore index offset */ |
1289 | } |
1290 | goto NoBitmap; |
1291 | |
1292 | FoundRange: |
1293 | image_offset = FT_NEXT_ULONG( p ); |
1294 | |
1295 | /* overflow check */ |
1296 | p = decoder->eblc_base + decoder->strike_index_array; |
1297 | if ( image_offset > (FT_ULong)( p_limit - p ) ) |
1298 | goto Failure; |
1299 | |
1300 | p += image_offset; |
1301 | if ( p + 8 > p_limit ) |
1302 | goto NoBitmap; |
1303 | |
1304 | /* now find the glyph's location and extend within the ebdt table */ |
1305 | index_format = FT_NEXT_USHORT( p ); |
1306 | image_format = FT_NEXT_USHORT( p ); |
1307 | image_offset = FT_NEXT_ULONG ( p ); |
1308 | |
1309 | switch ( index_format ) |
1310 | { |
1311 | case 1: /* 4-byte offsets relative to `image_offset' */ |
1312 | p += 4 * ( glyph_index - start ); |
1313 | if ( p + 8 > p_limit ) |
1314 | goto NoBitmap; |
1315 | |
1316 | image_start = FT_NEXT_ULONG( p ); |
1317 | image_end = FT_NEXT_ULONG( p ); |
1318 | |
1319 | if ( image_start == image_end ) /* missing glyph */ |
1320 | goto NoBitmap; |
1321 | break; |
1322 | |
1323 | case 2: /* big metrics, constant image size */ |
1324 | { |
1325 | FT_ULong image_size; |
1326 | |
1327 | |
1328 | if ( p + 12 > p_limit ) |
1329 | goto NoBitmap; |
1330 | |
1331 | image_size = FT_NEXT_ULONG( p ); |
1332 | |
1333 | if ( tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 ) ) |
1334 | goto NoBitmap; |
1335 | |
1336 | image_start = image_size * ( glyph_index - start ); |
1337 | image_end = image_start + image_size; |
1338 | } |
1339 | break; |
1340 | |
1341 | case 3: /* 2-byte offsets relative to 'image_offset' */ |
1342 | p += 2 * ( glyph_index - start ); |
1343 | if ( p + 4 > p_limit ) |
1344 | goto NoBitmap; |
1345 | |
1346 | image_start = FT_NEXT_USHORT( p ); |
1347 | image_end = FT_NEXT_USHORT( p ); |
1348 | |
1349 | if ( image_start == image_end ) /* missing glyph */ |
1350 | goto NoBitmap; |
1351 | break; |
1352 | |
1353 | case 4: /* sparse glyph array with (glyph,offset) pairs */ |
1354 | { |
1355 | FT_ULong mm, num_glyphs; |
1356 | |
1357 | |
1358 | if ( p + 4 > p_limit ) |
1359 | goto NoBitmap; |
1360 | |
1361 | num_glyphs = FT_NEXT_ULONG( p ); |
1362 | |
1363 | /* overflow check for p + ( num_glyphs + 1 ) * 4 */ |
1364 | if ( p + 4 > p_limit || |
1365 | num_glyphs > (FT_ULong)( ( ( p_limit - p ) >> 2 ) - 1 ) ) |
1366 | goto NoBitmap; |
1367 | |
1368 | for ( mm = 0; mm < num_glyphs; mm++ ) |
1369 | { |
1370 | FT_UInt gindex = FT_NEXT_USHORT( p ); |
1371 | |
1372 | |
1373 | if ( gindex == glyph_index ) |
1374 | { |
1375 | image_start = FT_NEXT_USHORT( p ); |
1376 | p += 2; |
1377 | image_end = FT_PEEK_USHORT( p ); |
1378 | break; |
1379 | } |
1380 | p += 2; |
1381 | } |
1382 | |
1383 | if ( mm >= num_glyphs ) |
1384 | goto NoBitmap; |
1385 | } |
1386 | break; |
1387 | |
1388 | case 5: /* constant metrics with sparse glyph codes */ |
1389 | case 19: |
1390 | { |
1391 | FT_ULong image_size, mm, num_glyphs; |
1392 | |
1393 | |
1394 | if ( p + 16 > p_limit ) |
1395 | goto NoBitmap; |
1396 | |
1397 | image_size = FT_NEXT_ULONG( p ); |
1398 | |
1399 | if ( tt_sbit_decoder_load_metrics( decoder, &p, p_limit, 1 ) ) |
1400 | goto NoBitmap; |
1401 | |
1402 | num_glyphs = FT_NEXT_ULONG( p ); |
1403 | |
1404 | /* overflow check for p + 2 * num_glyphs */ |
1405 | if ( num_glyphs > (FT_ULong)( ( p_limit - p ) >> 1 ) ) |
1406 | goto NoBitmap; |
1407 | |
1408 | for ( mm = 0; mm < num_glyphs; mm++ ) |
1409 | { |
1410 | FT_UInt gindex = FT_NEXT_USHORT( p ); |
1411 | |
1412 | |
1413 | if ( gindex == glyph_index ) |
1414 | break; |
1415 | } |
1416 | |
1417 | if ( mm >= num_glyphs ) |
1418 | goto NoBitmap; |
1419 | |
1420 | image_start = image_size * mm; |
1421 | image_end = image_start + image_size; |
1422 | } |
1423 | break; |
1424 | |
1425 | default: |
1426 | goto NoBitmap; |
1427 | } |
1428 | |
1429 | if ( image_start > image_end ) |
1430 | goto NoBitmap; |
1431 | |
1432 | image_end -= image_start; |
1433 | image_start = image_offset + image_start; |
1434 | |
1435 | FT_TRACE3(( "tt_sbit_decoder_load_image:" |
1436 | " found sbit (format %d) for glyph index %d\n" , |
1437 | image_format, glyph_index )); |
1438 | |
1439 | return tt_sbit_decoder_load_bitmap( decoder, |
1440 | image_format, |
1441 | image_start, |
1442 | image_end, |
1443 | x_pos, |
1444 | y_pos, |
1445 | recurse_count, |
1446 | metrics_only ); |
1447 | |
1448 | Failure: |
1449 | return FT_THROW( Invalid_Table ); |
1450 | |
1451 | NoBitmap: |
1452 | if ( recurse_count ) |
1453 | { |
1454 | FT_TRACE4(( "tt_sbit_decoder_load_image:" |
1455 | " missing subglyph sbit with glyph index %d\n" , |
1456 | glyph_index )); |
1457 | return FT_THROW( Invalid_Composite ); |
1458 | } |
1459 | |
1460 | FT_TRACE4(( "tt_sbit_decoder_load_image:" |
1461 | " no sbit found for glyph index %d\n" , glyph_index )); |
1462 | return FT_THROW( Missing_Bitmap ); |
1463 | } |
1464 | |
1465 | |
1466 | static FT_Error |
1467 | tt_face_load_sbix_image( TT_Face face, |
1468 | FT_ULong strike_index, |
1469 | FT_UInt glyph_index, |
1470 | FT_Stream stream, |
1471 | FT_Bitmap *map, |
1472 | TT_SBit_MetricsRec *metrics, |
1473 | FT_Bool metrics_only ) |
1474 | { |
1475 | FT_UInt strike_offset, glyph_start, glyph_end; |
1476 | FT_Int originOffsetX, originOffsetY; |
1477 | FT_Tag graphicType; |
1478 | FT_Int recurse_depth = 0; |
1479 | |
1480 | FT_Error error; |
1481 | FT_Byte* p; |
1482 | |
1483 | FT_UNUSED( map ); |
1484 | #ifndef FT_CONFIG_OPTION_USE_PNG |
1485 | FT_UNUSED( metrics_only ); |
1486 | #endif |
1487 | |
1488 | |
1489 | strike_index = face->sbit_strike_map[strike_index]; |
1490 | |
1491 | metrics->width = 0; |
1492 | metrics->height = 0; |
1493 | |
1494 | p = face->sbit_table + 8 + 4 * strike_index; |
1495 | strike_offset = FT_NEXT_ULONG( p ); |
1496 | |
1497 | retry: |
1498 | if ( glyph_index > (FT_UInt)face->root.num_glyphs ) |
1499 | return FT_THROW( Invalid_Argument ); |
1500 | |
1501 | if ( strike_offset >= face->ebdt_size || |
1502 | face->ebdt_size - strike_offset < 4 + glyph_index * 4 + 8 ) |
1503 | return FT_THROW( Invalid_File_Format ); |
1504 | |
1505 | if ( FT_STREAM_SEEK( face->ebdt_start + |
1506 | strike_offset + 4 + |
1507 | glyph_index * 4 ) || |
1508 | FT_FRAME_ENTER( 8 ) ) |
1509 | return error; |
1510 | |
1511 | glyph_start = FT_GET_ULONG(); |
1512 | glyph_end = FT_GET_ULONG(); |
1513 | |
1514 | FT_FRAME_EXIT(); |
1515 | |
1516 | if ( glyph_start == glyph_end ) |
1517 | return FT_THROW( Missing_Bitmap ); |
1518 | if ( glyph_start > glyph_end || |
1519 | glyph_end - glyph_start < 8 || |
1520 | face->ebdt_size - strike_offset < glyph_end ) |
1521 | return FT_THROW( Invalid_File_Format ); |
1522 | |
1523 | if ( FT_STREAM_SEEK( face->ebdt_start + strike_offset + glyph_start ) || |
1524 | FT_FRAME_ENTER( glyph_end - glyph_start ) ) |
1525 | return error; |
1526 | |
1527 | originOffsetX = FT_GET_SHORT(); |
1528 | originOffsetY = FT_GET_SHORT(); |
1529 | |
1530 | graphicType = FT_GET_TAG4(); |
1531 | |
1532 | switch ( graphicType ) |
1533 | { |
1534 | case FT_MAKE_TAG( 'd', 'u', 'p', 'e' ): |
1535 | if ( recurse_depth < 4 ) |
1536 | { |
1537 | glyph_index = FT_GET_USHORT(); |
1538 | FT_FRAME_EXIT(); |
1539 | recurse_depth++; |
1540 | goto retry; |
1541 | } |
1542 | error = FT_THROW( Invalid_File_Format ); |
1543 | break; |
1544 | |
1545 | case FT_MAKE_TAG( 'p', 'n', 'g', ' ' ): |
1546 | #ifdef FT_CONFIG_OPTION_USE_PNG |
1547 | error = Load_SBit_Png( face->root.glyph, |
1548 | 0, |
1549 | 0, |
1550 | 32, |
1551 | metrics, |
1552 | stream->memory, |
1553 | stream->cursor, |
1554 | glyph_end - glyph_start - 8, |
1555 | TRUE, |
1556 | metrics_only ); |
1557 | #else |
1558 | error = FT_THROW( Unimplemented_Feature ); |
1559 | #endif |
1560 | break; |
1561 | |
1562 | case FT_MAKE_TAG( 'j', 'p', 'g', ' ' ): |
1563 | case FT_MAKE_TAG( 't', 'i', 'f', 'f' ): |
1564 | case FT_MAKE_TAG( 'r', 'g', 'b', 'l' ): /* used on iOS 7.1 */ |
1565 | error = FT_THROW( Unknown_File_Format ); |
1566 | break; |
1567 | |
1568 | default: |
1569 | error = FT_THROW( Unimplemented_Feature ); |
1570 | break; |
1571 | } |
1572 | |
1573 | FT_FRAME_EXIT(); |
1574 | |
1575 | if ( !error ) |
1576 | { |
1577 | FT_Short abearing; |
1578 | FT_UShort aadvance; |
1579 | |
1580 | |
1581 | tt_face_get_metrics( face, FALSE, glyph_index, &abearing, &aadvance ); |
1582 | |
1583 | metrics->horiBearingX = (FT_Short)originOffsetX; |
1584 | metrics->horiBearingY = (FT_Short)( -originOffsetY + metrics->height ); |
1585 | metrics->horiAdvance = (FT_UShort)( aadvance * |
1586 | face->root.size->metrics.x_ppem / |
1587 | face->header.Units_Per_EM ); |
1588 | } |
1589 | |
1590 | return error; |
1591 | } |
1592 | |
1593 | FT_LOCAL( FT_Error ) |
1594 | tt_face_load_sbit_image( TT_Face face, |
1595 | FT_ULong strike_index, |
1596 | FT_UInt glyph_index, |
1597 | FT_UInt load_flags, |
1598 | FT_Stream stream, |
1599 | FT_Bitmap *map, |
1600 | TT_SBit_MetricsRec *metrics ) |
1601 | { |
1602 | FT_Error error = FT_Err_Ok; |
1603 | |
1604 | |
1605 | switch ( (FT_UInt)face->sbit_table_type ) |
1606 | { |
1607 | case TT_SBIT_TABLE_TYPE_EBLC: |
1608 | case TT_SBIT_TABLE_TYPE_CBLC: |
1609 | { |
1610 | TT_SBitDecoderRec decoder[1]; |
1611 | |
1612 | |
1613 | error = tt_sbit_decoder_init( decoder, face, strike_index, metrics ); |
1614 | if ( !error ) |
1615 | { |
1616 | error = tt_sbit_decoder_load_image( |
1617 | decoder, |
1618 | glyph_index, |
1619 | 0, |
1620 | 0, |
1621 | 0, |
1622 | ( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) != 0 ); |
1623 | tt_sbit_decoder_done( decoder ); |
1624 | } |
1625 | } |
1626 | break; |
1627 | |
1628 | case TT_SBIT_TABLE_TYPE_SBIX: |
1629 | error = tt_face_load_sbix_image( |
1630 | face, |
1631 | strike_index, |
1632 | glyph_index, |
1633 | stream, |
1634 | map, |
1635 | metrics, |
1636 | ( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) != 0 ); |
1637 | break; |
1638 | |
1639 | default: |
1640 | error = FT_THROW( Unknown_File_Format ); |
1641 | break; |
1642 | } |
1643 | |
1644 | /* Flatten color bitmaps if color was not requested. */ |
1645 | if ( !error && |
1646 | !( load_flags & FT_LOAD_COLOR ) && |
1647 | !( load_flags & FT_LOAD_BITMAP_METRICS_ONLY ) && |
1648 | map->pixel_mode == FT_PIXEL_MODE_BGRA ) |
1649 | { |
1650 | FT_Bitmap new_map; |
1651 | FT_Library library = face->root.glyph->library; |
1652 | |
1653 | |
1654 | FT_Bitmap_Init( &new_map ); |
1655 | |
1656 | /* Convert to 8bit grayscale. */ |
1657 | error = FT_Bitmap_Convert( library, map, &new_map, 1 ); |
1658 | if ( error ) |
1659 | FT_Bitmap_Done( library, &new_map ); |
1660 | else |
1661 | { |
1662 | map->pixel_mode = new_map.pixel_mode; |
1663 | map->pitch = new_map.pitch; |
1664 | map->num_grays = new_map.num_grays; |
1665 | |
1666 | ft_glyphslot_set_bitmap( face->root.glyph, new_map.buffer ); |
1667 | face->root.glyph->internal->flags |= FT_GLYPH_OWN_BITMAP; |
1668 | } |
1669 | } |
1670 | |
1671 | return error; |
1672 | } |
1673 | |
1674 | #else /* !TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ |
1675 | |
1676 | /* ANSI C doesn't like empty source files */ |
1677 | typedef int _tt_sbit_dummy; |
1678 | |
1679 | #endif /* !TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ |
1680 | |
1681 | |
1682 | /* END */ |
1683 | |