1/****************************************************************************
2 *
3 * cidgload.c
4 *
5 * CID-keyed Type1 Glyph Loader (body).
6 *
7 * Copyright (C) 1996-2023 by
8 * David Turner, Robert Wilhelm, and Werner Lemberg.
9 *
10 * This file is part of the FreeType project, and may only be used,
11 * modified, and distributed under the terms of the FreeType project
12 * license, LICENSE.TXT. By continuing to use, modify, or distribute
13 * this file you indicate that you have read the license and
14 * understand and accept it fully.
15 *
16 */
17
18
19#include "cidload.h"
20#include "cidgload.h"
21#include <freetype/internal/ftdebug.h>
22#include <freetype/internal/ftstream.h>
23#include <freetype/ftoutln.h>
24#include <freetype/internal/ftcalc.h>
25
26#include <freetype/internal/psaux.h>
27#include <freetype/internal/cfftypes.h>
28#include <freetype/ftdriver.h>
29
30#include "ciderrs.h"
31
32
33 /**************************************************************************
34 *
35 * The macro FT_COMPONENT is used in trace mode. It is an implicit
36 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
37 * messages during execution.
38 */
39#undef FT_COMPONENT
40#define FT_COMPONENT cidgload
41
42
43 /*
44 * A helper function to compute FD number (`fd_select`), the offset to the
45 * head of the glyph data (`off1`), and the offset to the and of the glyph
46 * data (`off2`).
47 *
48 * The number how many times `cid_get_offset` is invoked can be controlled
49 * by the number of non-NULL arguments. If `fd_select` is non-NULL but
50 * `off1` and `off2` are NULL, `cid_get_offset` is invoked only for
51 * `fd_select`; `off1` and `off2` are not validated.
52 *
53 */
54 FT_LOCAL_DEF( FT_Error )
55 cid_compute_fd_and_offsets( CID_Face face,
56 FT_UInt glyph_index,
57 FT_ULong* fd_select_p,
58 FT_ULong* off1_p,
59 FT_ULong* off2_p )
60 {
61 FT_Error error = FT_Err_Ok;
62
63 CID_FaceInfo cid = &face->cid;
64 FT_Stream stream = face->cid_stream;
65 FT_UInt entry_len = cid->fd_bytes + cid->gd_bytes;
66
67 FT_Byte* p;
68 FT_Bool need_frame_exit = 0;
69 FT_ULong fd_select, off1, off2;
70
71
72 /* For ordinary fonts, read the CID font dictionary index */
73 /* and charstring offset from the CIDMap. */
74
75 if ( FT_STREAM_SEEK( cid->data_offset + cid->cidmap_offset +
76 glyph_index * entry_len ) ||
77 FT_FRAME_ENTER( 2 * entry_len ) )
78 goto Exit;
79
80 need_frame_exit = 1;
81
82 p = (FT_Byte*)stream->cursor;
83 fd_select = cid_get_offset( &p, cid->fd_bytes );
84 off1 = cid_get_offset( &p, cid->gd_bytes );
85
86 p += cid->fd_bytes;
87 off2 = cid_get_offset( &p, cid->gd_bytes );
88
89 if ( fd_select_p )
90 *fd_select_p = fd_select;
91 if ( off1_p )
92 *off1_p = off1;
93 if ( off2_p )
94 *off2_p = off2;
95
96 if ( fd_select >= cid->num_dicts )
97 {
98 /*
99 * fd_select == 0xFF is often used to indicate that the CID
100 * has no charstring to be rendered, similar to GID = 0xFFFF
101 * in TrueType fonts.
102 */
103 if ( ( cid->fd_bytes == 1 && fd_select == 0xFFU ) ||
104 ( cid->fd_bytes == 2 && fd_select == 0xFFFFU ) )
105 {
106 FT_TRACE1(( "cid_load_glyph: fail for glyph index %d:\n",
107 glyph_index ));
108 FT_TRACE1(( " FD number %ld is the maximum\n",
109 fd_select ));
110 FT_TRACE1(( " integer fitting into %d byte%s\n",
111 cid->fd_bytes, cid->fd_bytes == 1 ? "" : "s" ));
112 }
113 else
114 {
115 FT_TRACE0(( "cid_load_glyph: fail for glyph index %d:\n",
116 glyph_index ));
117 FT_TRACE0(( " FD number %ld is larger\n",
118 fd_select ));
119 FT_TRACE0(( " than number of dictionaries (%d)\n",
120 cid->num_dicts ));
121 }
122
123 error = FT_THROW( Invalid_Offset );
124 goto Exit;
125 }
126 else if ( off2 > stream->size )
127 {
128 FT_TRACE0(( "cid_load_glyph: fail for glyph index %d:\n",
129 glyph_index ));
130 FT_TRACE0(( " end of the glyph data\n" ));
131 FT_TRACE0(( " is beyond the data stream\n" ));
132
133 error = FT_THROW( Invalid_Offset );
134 goto Exit;
135 }
136 else if ( off1 > off2 )
137 {
138 FT_TRACE0(( "cid_load_glyph: fail for glyph index %d:\n",
139 glyph_index ));
140 FT_TRACE0(( " the end position of glyph data\n" ));
141 FT_TRACE0(( " is set before the start position\n" ));
142
143 error = FT_THROW( Invalid_Offset );
144 }
145
146 Exit:
147 if ( need_frame_exit )
148 FT_FRAME_EXIT();
149
150 return error;
151 }
152
153
154 FT_CALLBACK_DEF( FT_Error )
155 cid_load_glyph( T1_Decoder decoder,
156 FT_UInt glyph_index )
157 {
158 CID_Face face = (CID_Face)decoder->builder.face;
159 CID_FaceInfo cid = &face->cid;
160 FT_Byte* p;
161 FT_ULong fd_select;
162 FT_Stream stream = face->cid_stream;
163 FT_Error error = FT_Err_Ok;
164 FT_Byte* charstring = NULL;
165 FT_Memory memory = face->root.memory;
166 FT_ULong glyph_length = 0;
167 PSAux_Service psaux = (PSAux_Service)face->psaux;
168
169 FT_Bool force_scaling = FALSE;
170
171#ifdef FT_CONFIG_OPTION_INCREMENTAL
172 FT_Incremental_InterfaceRec *inc =
173 face->root.internal->incremental_interface;
174#endif
175
176
177 FT_TRACE1(( "cid_load_glyph: glyph index %u\n", glyph_index ));
178
179#ifdef FT_CONFIG_OPTION_INCREMENTAL
180
181 /* For incremental fonts get the character data using */
182 /* the callback function. */
183 if ( inc )
184 {
185 FT_Data glyph_data;
186
187
188 error = inc->funcs->get_glyph_data( inc->object,
189 glyph_index, &glyph_data );
190 if ( error || glyph_data.length < cid->fd_bytes )
191 goto Exit;
192
193 p = (FT_Byte*)glyph_data.pointer;
194 fd_select = cid_get_offset( &p, cid->fd_bytes );
195
196 glyph_length = glyph_data.length - cid->fd_bytes;
197
198 if ( !FT_QALLOC( charstring, glyph_length ) )
199 FT_MEM_COPY( charstring, glyph_data.pointer + cid->fd_bytes,
200 glyph_length );
201
202 inc->funcs->free_glyph_data( inc->object, &glyph_data );
203
204 if ( error )
205 goto Exit;
206 }
207
208 else
209
210#endif /* FT_CONFIG_OPTION_INCREMENTAL */
211 {
212 FT_ULong off1, off2;
213
214
215 error = cid_compute_fd_and_offsets( face, glyph_index,
216 &fd_select, &off1, &off2 );
217 if ( error )
218 goto Exit;
219
220 glyph_length = off2 - off1;
221
222 if ( glyph_length == 0 ||
223 FT_QALLOC( charstring, glyph_length ) ||
224 FT_STREAM_READ_AT( cid->data_offset + off1,
225 charstring, glyph_length ) )
226 goto Exit;
227 }
228
229 /* Now set up the subrs array and parse the charstrings. */
230 {
231 CID_FaceDict dict;
232 CID_Subrs cid_subrs = face->subrs + fd_select;
233 FT_UInt cs_offset;
234
235
236 /* Set up subrs */
237 decoder->num_subrs = cid_subrs->num_subrs;
238 decoder->subrs = cid_subrs->code;
239 decoder->subrs_len = 0;
240 decoder->subrs_hash = NULL;
241
242 /* Set up font matrix */
243 dict = cid->font_dicts + fd_select;
244
245 decoder->font_matrix = dict->font_matrix;
246 decoder->font_offset = dict->font_offset;
247 decoder->lenIV = dict->private_dict.lenIV;
248
249 /* Decode the charstring. */
250
251 /* Adjustment for seed bytes. */
252 cs_offset = decoder->lenIV >= 0 ? (FT_UInt)decoder->lenIV : 0;
253 if ( cs_offset > glyph_length )
254 {
255 FT_TRACE0(( "cid_load_glyph: fail for glyph_index=%d, "
256 "offset to the charstring is beyond glyph length\n",
257 glyph_index ));
258 error = FT_THROW( Invalid_Offset );
259 goto Exit;
260 }
261
262 /* Decrypt only if lenIV >= 0. */
263 if ( decoder->lenIV >= 0 )
264 psaux->t1_decrypt( charstring, glyph_length, 4330 );
265
266 /* choose which renderer to use */
267#ifdef T1_CONFIG_OPTION_OLD_ENGINE
268 if ( ( (PS_Driver)FT_FACE_DRIVER( face ) )->hinting_engine ==
269 FT_HINTING_FREETYPE ||
270 decoder->builder.metrics_only )
271 error = psaux->t1_decoder_funcs->parse_charstrings_old(
272 decoder,
273 charstring + cs_offset,
274 glyph_length - cs_offset );
275#else
276 if ( decoder->builder.metrics_only )
277 error = psaux->t1_decoder_funcs->parse_metrics(
278 decoder,
279 charstring + cs_offset,
280 glyph_length - cs_offset );
281#endif
282 else
283 {
284 PS_Decoder psdecoder;
285 CFF_SubFontRec subfont;
286
287
288 psaux->ps_decoder_init( &psdecoder, decoder, TRUE );
289
290 psaux->t1_make_subfont( FT_FACE( face ),
291 &dict->private_dict,
292 &subfont );
293 psdecoder.current_subfont = &subfont;
294
295 error = psaux->t1_decoder_funcs->parse_charstrings(
296 &psdecoder,
297 charstring + cs_offset,
298 glyph_length - cs_offset );
299
300 /* Adobe's engine uses 16.16 numbers everywhere; */
301 /* as a consequence, glyphs larger than 2000ppem get rejected */
302 if ( FT_ERR_EQ( error, Glyph_Too_Big ) )
303 {
304 /* this time, we retry unhinted and scale up the glyph later on */
305 /* (the engine uses and sets the hardcoded value 0x10000 / 64 = */
306 /* 0x400 for both `x_scale' and `y_scale' in this case) */
307 ((CID_GlyphSlot)decoder->builder.glyph)->hint = FALSE;
308
309 force_scaling = TRUE;
310
311 error = psaux->t1_decoder_funcs->parse_charstrings(
312 &psdecoder,
313 charstring + cs_offset,
314 glyph_length - cs_offset );
315 }
316 }
317 }
318
319#ifdef FT_CONFIG_OPTION_INCREMENTAL
320
321 /* Incremental fonts can optionally override the metrics. */
322 if ( !error && inc && inc->funcs->get_glyph_metrics )
323 {
324 FT_Incremental_MetricsRec metrics;
325
326
327 metrics.bearing_x = FIXED_TO_INT( decoder->builder.left_bearing.x );
328 metrics.bearing_y = 0;
329 metrics.advance = FIXED_TO_INT( decoder->builder.advance.x );
330 metrics.advance_v = FIXED_TO_INT( decoder->builder.advance.y );
331
332 error = inc->funcs->get_glyph_metrics( inc->object,
333 glyph_index, FALSE, &metrics );
334
335 decoder->builder.left_bearing.x = INT_TO_FIXED( metrics.bearing_x );
336 decoder->builder.advance.x = INT_TO_FIXED( metrics.advance );
337 decoder->builder.advance.y = INT_TO_FIXED( metrics.advance_v );
338 }
339
340#endif /* FT_CONFIG_OPTION_INCREMENTAL */
341
342 Exit:
343 FT_FREE( charstring );
344
345 ((CID_GlyphSlot)decoder->builder.glyph)->scaled = force_scaling;
346
347 return error;
348 }
349
350
351#if 0
352
353
354 /*************************************************************************/
355 /*************************************************************************/
356 /*************************************************************************/
357 /********** *********/
358 /********** *********/
359 /********** COMPUTE THE MAXIMUM ADVANCE WIDTH *********/
360 /********** *********/
361 /********** The following code is in charge of computing *********/
362 /********** the maximum advance width of the font. It *********/
363 /********** quickly processes each glyph charstring to *********/
364 /********** extract the value from either a `sbw' or `seac' *********/
365 /********** operator. *********/
366 /********** *********/
367 /*************************************************************************/
368 /*************************************************************************/
369 /*************************************************************************/
370
371
372 FT_LOCAL_DEF( FT_Error )
373 cid_face_compute_max_advance( CID_Face face,
374 FT_Int* max_advance )
375 {
376 FT_Error error;
377 T1_DecoderRec decoder;
378 FT_Int glyph_index;
379
380 PSAux_Service psaux = (PSAux_Service)face->psaux;
381
382
383 *max_advance = 0;
384
385 /* Initialize load decoder */
386 error = psaux->t1_decoder_funcs->init( &decoder,
387 (FT_Face)face,
388 0, /* size */
389 0, /* glyph slot */
390 0, /* glyph names! XXX */
391 0, /* blend == 0 */
392 0, /* hinting == 0 */
393 cid_load_glyph );
394 if ( error )
395 return error;
396
397 /* TODO: initialize decoder.len_buildchar and decoder.buildchar */
398 /* if we ever support CID-keyed multiple master fonts */
399
400 decoder.builder.metrics_only = 1;
401 decoder.builder.load_points = 0;
402
403 /* for each glyph, parse the glyph charstring and extract */
404 /* the advance width */
405 for ( glyph_index = 0; glyph_index < face->root.num_glyphs;
406 glyph_index++ )
407 {
408 /* now get load the unscaled outline */
409 error = cid_load_glyph( &decoder, glyph_index );
410 /* ignore the error if one occurred - skip to next glyph */
411 }
412
413 *max_advance = FIXED_TO_INT( decoder.builder.advance.x );
414
415 psaux->t1_decoder_funcs->done( &decoder );
416
417 return FT_Err_Ok;
418 }
419
420
421#endif /* 0 */
422
423
424 FT_LOCAL_DEF( FT_Error )
425 cid_slot_load_glyph( FT_GlyphSlot cidglyph, /* CID_GlyphSlot */
426 FT_Size cidsize, /* CID_Size */
427 FT_UInt glyph_index,
428 FT_Int32 load_flags )
429 {
430 CID_GlyphSlot glyph = (CID_GlyphSlot)cidglyph;
431 FT_Error error;
432 T1_DecoderRec decoder;
433 CID_Face face = (CID_Face)cidglyph->face;
434 FT_Bool hinting;
435 FT_Bool scaled;
436
437 PSAux_Service psaux = (PSAux_Service)face->psaux;
438 FT_Matrix font_matrix;
439 FT_Vector font_offset;
440 FT_Bool must_finish_decoder = FALSE;
441
442
443 if ( glyph_index >= (FT_UInt)face->root.num_glyphs )
444 {
445 error = FT_THROW( Invalid_Argument );
446 goto Exit;
447 }
448
449 if ( load_flags & FT_LOAD_NO_RECURSE )
450 load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;
451
452 glyph->x_scale = cidsize->metrics.x_scale;
453 glyph->y_scale = cidsize->metrics.y_scale;
454
455 cidglyph->outline.n_points = 0;
456 cidglyph->outline.n_contours = 0;
457
458 hinting = FT_BOOL( ( load_flags & FT_LOAD_NO_SCALE ) == 0 &&
459 ( load_flags & FT_LOAD_NO_HINTING ) == 0 );
460 scaled = FT_BOOL( ( load_flags & FT_LOAD_NO_SCALE ) == 0 );
461
462 glyph->hint = hinting;
463 glyph->scaled = scaled;
464 cidglyph->format = FT_GLYPH_FORMAT_OUTLINE;
465
466 error = psaux->t1_decoder_funcs->init( &decoder,
467 cidglyph->face,
468 cidsize,
469 cidglyph,
470 0, /* glyph names -- XXX */
471 0, /* blend == 0 */
472 hinting,
473 FT_LOAD_TARGET_MODE( load_flags ),
474 cid_load_glyph );
475 if ( error )
476 goto Exit;
477
478 /* TODO: initialize decoder.len_buildchar and decoder.buildchar */
479 /* if we ever support CID-keyed multiple master fonts */
480
481 must_finish_decoder = TRUE;
482
483 /* set up the decoder */
484 decoder.builder.no_recurse = FT_BOOL( load_flags & FT_LOAD_NO_RECURSE );
485
486 error = cid_load_glyph( &decoder, glyph_index );
487 if ( error )
488 goto Exit;
489
490 /* copy flags back for forced scaling */
491 hinting = glyph->hint;
492 scaled = glyph->scaled;
493
494 font_matrix = decoder.font_matrix;
495 font_offset = decoder.font_offset;
496
497 /* save new glyph tables */
498 psaux->t1_decoder_funcs->done( &decoder );
499
500 must_finish_decoder = FALSE;
501
502 /* now set the metrics -- this is rather simple, as */
503 /* the left side bearing is the xMin, and the top side */
504 /* bearing the yMax */
505 cidglyph->outline.flags &= FT_OUTLINE_OWNER;
506 cidglyph->outline.flags |= FT_OUTLINE_REVERSE_FILL;
507
508 /* for composite glyphs, return only left side bearing and */
509 /* advance width */
510 if ( load_flags & FT_LOAD_NO_RECURSE )
511 {
512 FT_Slot_Internal internal = cidglyph->internal;
513
514
515 cidglyph->metrics.horiBearingX =
516 FIXED_TO_INT( decoder.builder.left_bearing.x );
517 cidglyph->metrics.horiAdvance =
518 FIXED_TO_INT( decoder.builder.advance.x );
519
520 internal->glyph_matrix = font_matrix;
521 internal->glyph_delta = font_offset;
522 internal->glyph_transformed = 1;
523 }
524 else
525 {
526 FT_BBox cbox;
527 FT_Glyph_Metrics* metrics = &cidglyph->metrics;
528
529
530 /* copy the _unscaled_ advance width */
531 metrics->horiAdvance =
532 FIXED_TO_INT( decoder.builder.advance.x );
533 cidglyph->linearHoriAdvance =
534 FIXED_TO_INT( decoder.builder.advance.x );
535 cidglyph->internal->glyph_transformed = 0;
536
537 /* make up vertical ones */
538 metrics->vertAdvance = ( face->cid.font_bbox.yMax -
539 face->cid.font_bbox.yMin ) >> 16;
540 cidglyph->linearVertAdvance = metrics->vertAdvance;
541
542 cidglyph->format = FT_GLYPH_FORMAT_OUTLINE;
543
544 if ( cidsize->metrics.y_ppem < 24 )
545 cidglyph->outline.flags |= FT_OUTLINE_HIGH_PRECISION;
546
547 /* apply the font matrix, if any */
548 if ( font_matrix.xx != 0x10000L || font_matrix.yy != 0x10000L ||
549 font_matrix.xy != 0 || font_matrix.yx != 0 )
550 {
551 FT_Outline_Transform( &cidglyph->outline, &font_matrix );
552
553 metrics->horiAdvance = FT_MulFix( metrics->horiAdvance,
554 font_matrix.xx );
555 metrics->vertAdvance = FT_MulFix( metrics->vertAdvance,
556 font_matrix.yy );
557 }
558
559 if ( font_offset.x || font_offset.y )
560 {
561 FT_Outline_Translate( &cidglyph->outline,
562 font_offset.x,
563 font_offset.y );
564
565 metrics->horiAdvance += font_offset.x;
566 metrics->vertAdvance += font_offset.y;
567 }
568
569 if ( ( load_flags & FT_LOAD_NO_SCALE ) == 0 || scaled )
570 {
571 /* scale the outline and the metrics */
572 FT_Int n;
573 FT_Outline* cur = decoder.builder.base;
574 FT_Vector* vec = cur->points;
575 FT_Fixed x_scale = glyph->x_scale;
576 FT_Fixed y_scale = glyph->y_scale;
577
578
579 /* First of all, scale the points */
580 if ( !hinting || !decoder.builder.hints_funcs )
581 for ( n = cur->n_points; n > 0; n--, vec++ )
582 {
583 vec->x = FT_MulFix( vec->x, x_scale );
584 vec->y = FT_MulFix( vec->y, y_scale );
585 }
586
587 /* Then scale the metrics */
588 metrics->horiAdvance = FT_MulFix( metrics->horiAdvance, x_scale );
589 metrics->vertAdvance = FT_MulFix( metrics->vertAdvance, y_scale );
590 }
591
592 /* compute the other metrics */
593 FT_Outline_Get_CBox( &cidglyph->outline, &cbox );
594
595 metrics->width = cbox.xMax - cbox.xMin;
596 metrics->height = cbox.yMax - cbox.yMin;
597
598 metrics->horiBearingX = cbox.xMin;
599 metrics->horiBearingY = cbox.yMax;
600
601 if ( load_flags & FT_LOAD_VERTICAL_LAYOUT )
602 {
603 /* make up vertical ones */
604 ft_synthesize_vertical_metrics( metrics,
605 metrics->vertAdvance );
606 }
607 }
608
609 Exit:
610
611 if ( must_finish_decoder )
612 psaux->t1_decoder_funcs->done( &decoder );
613
614 return error;
615 }
616
617
618/* END */
619