1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 // This file is available under and governed by the GNU General Public
26 // License version 2 only, as published by the Free Software Foundation.
27 // However, the following notice accompanied the original version of this
28 // file:
29 //
30 /*
31 * Copyright © 2009 Red Hat, Inc.
32 * Copyright © 2009 Keith Stribley
33 * Copyright © 2015 Google, Inc.
34 *
35 * This is part of HarfBuzz, a text shaping library.
36 *
37 * Permission is hereby granted, without written agreement and without
38 * license or royalty fees, to use, copy, modify, and distribute this
39 * software and its documentation for any purpose, provided that the
40 * above copyright notice and the following two paragraphs appear in
41 * all copies of this software.
42 *
43 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
44 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
45 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
46 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
47 * DAMAGE.
48 *
49 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
50 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
51 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
52 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
53 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
54 *
55 * Red Hat Author(s): Behdad Esfahbod
56 * Google Author(s): Behdad Esfahbod
57 */
58
59 #include "hb-private.hh"
60
61 #include "hb-ft.h"
62
63 #include "hb-font-private.hh"
64
65 #include FT_ADVANCES_H
66 #include FT_TRUETYPE_TABLES_H
67
68
69
70 #ifndef HB_DEBUG_FT
71 #define HB_DEBUG_FT (HB_DEBUG+0)
72 #endif
73
74
75 /* TODO:
76 *
77 * In general, this file does a fine job of what it's supposed to do.
78 * There are, however, things that need more work:
79 *
80 * - I remember seeing FT_Get_Advance() without the NO_HINTING flag to be buggy.
81 * Have not investigated.
82 *
83 * - FreeType works in 26.6 mode. Clients can decide to use that mode, and everything
84 * would work fine. However, we also abuse this API for performing in font-space,
85 * but don't pass the correct flags to FreeType. We just abuse the no-hinting mode
86 * for that, such that no rounding etc happens. As such, we don't set ppem, and
87 * pass NO_HINTING as load_flags. Would be much better to use NO_SCALE, and scale
88 * ourselves, like we do in uniscribe, etc.
89 *
90 * - We don't handle / allow for emboldening / obliqueing.
91 *
92 * - In the future, we should add constructors to create fonts in font space?
93 *
94 * - FT_Load_Glyph() is exteremely costly. Do something about it?
95 */
96
97
98 struct hb_ft_font_t
99 {
100 FT_Face ft_face;
101 int load_flags;
102 bool unref; /* Whether to destroy ft_face when done. */
103 };
104
105 static hb_ft_font_t *
106 _hb_ft_font_create (FT_Face ft_face, bool unref)
107 {
108 hb_ft_font_t *ft_font = (hb_ft_font_t *) calloc (1, sizeof (hb_ft_font_t));
109
110 if (unlikely (!ft_font))
111 return NULL;
112
113 ft_font->ft_face = ft_face;
114 ft_font->unref = unref;
115
116 ft_font->load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
117
118 return ft_font;
119 }
120
121 static void
122 _hb_ft_font_destroy (hb_ft_font_t *ft_font)
123 {
124 if (ft_font->unref)
125 FT_Done_Face (ft_font->ft_face);
126
127 free (ft_font);
128 }
129
130 /**
131 * hb_ft_font_set_load_flags:
132 * @font:
133 * @load_flags:
134 *
135 *
136 *
137 * Since: 1.0.5
138 **/
139 void
140 hb_ft_font_set_load_flags (hb_font_t *font, int load_flags)
141 {
142 if (font->immutable)
143 return;
144
145 if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
146 return;
147
148 hb_ft_font_t *ft_font = (hb_ft_font_t *) font->user_data;
149
150 ft_font->load_flags = load_flags;
151 }
152
153 /**
154 * hb_ft_font_get_load_flags:
155 * @font:
156 *
157 *
158 *
159 * Return value:
160 * Since: 1.0.5
161 **/
162 int
163 hb_ft_font_get_load_flags (hb_font_t *font)
164 {
165 if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
166 return 0;
167
168 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
169
170 return ft_font->load_flags;
171 }
172
173 FT_Face
174 hb_ft_font_get_face (hb_font_t *font)
175 {
176 if (font->destroy != (hb_destroy_func_t) _hb_ft_font_destroy)
177 return NULL;
178
179 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font->user_data;
180
181 return ft_font->ft_face;
182 }
183
184
185
186 static hb_bool_t
187 hb_ft_get_glyph (hb_font_t *font HB_UNUSED,
188 void *font_data,
189 hb_codepoint_t unicode,
190 hb_codepoint_t variation_selector,
191 hb_codepoint_t *glyph,
192 void *user_data HB_UNUSED)
193
194 {
195 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
196 unsigned int g;
197
198 if (likely (!variation_selector))
199 g = FT_Get_Char_Index (ft_font->ft_face, unicode);
200 else
201 g = FT_Face_GetCharVariantIndex (ft_font->ft_face, unicode, variation_selector);
202
203 if (unlikely (!g))
204 return false;
205
206 *glyph = g;
207 return true;
208 }
209
210 static hb_position_t
211 hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
212 void *font_data,
213 hb_codepoint_t glyph,
214 void *user_data HB_UNUSED)
215 {
216 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
217 FT_Fixed v;
218
219 if (unlikely (FT_Get_Advance (ft_font->ft_face, glyph, ft_font->load_flags, &v)))
220 return 0;
221
222 if (font->x_scale < 0)
223 v = -v;
224
225 return (v + (1<<9)) >> 10;
226 }
227
228 static hb_position_t
229 hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
230 void *font_data,
231 hb_codepoint_t glyph,
232 void *user_data HB_UNUSED)
233 {
234 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
235 FT_Fixed v;
236
237 if (unlikely (FT_Get_Advance (ft_font->ft_face, glyph, ft_font->load_flags | FT_LOAD_VERTICAL_LAYOUT, &v)))
238 return 0;
239
240 if (font->y_scale < 0)
241 v = -v;
242
243 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
244 * have a Y growing upward. Hence the extra negation. */
245 return (-v + (1<<9)) >> 10;
246 }
247
248 static hb_bool_t
249 hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED,
250 void *font_data HB_UNUSED,
251 hb_codepoint_t glyph HB_UNUSED,
252 hb_position_t *x HB_UNUSED,
253 hb_position_t *y HB_UNUSED,
254 void *user_data HB_UNUSED)
255 {
256 /* We always work in the horizontal coordinates. */
257 return true;
258 }
259
260 static hb_bool_t
261 hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED,
262 void *font_data,
263 hb_codepoint_t glyph,
264 hb_position_t *x,
265 hb_position_t *y,
266 void *user_data HB_UNUSED)
267 {
268 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
269 FT_Face ft_face = ft_font->ft_face;
270
271 if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
272 return false;
273
274 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates
275 * have a Y growing upward. Hence the extra negation. */
276 *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX;
277 *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY);
278
279 if (font->x_scale < 0)
280 *x = -*x;
281 if (font->y_scale < 0)
282 *y = -*y;
283
284 return true;
285 }
286
287 static hb_position_t
288 hb_ft_get_glyph_h_kerning (hb_font_t *font,
289 void *font_data,
290 hb_codepoint_t left_glyph,
291 hb_codepoint_t right_glyph,
292 void *user_data HB_UNUSED)
293 {
294 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
295 FT_Vector kerningv;
296
297 FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED;
298 if (FT_Get_Kerning (ft_font->ft_face, left_glyph, right_glyph, mode, &kerningv))
299 return 0;
300
301 return kerningv.x;
302 }
303
304 static hb_position_t
305 hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,
306 void *font_data HB_UNUSED,
307 hb_codepoint_t top_glyph HB_UNUSED,
308 hb_codepoint_t bottom_glyph HB_UNUSED,
309 void *user_data HB_UNUSED)
310 {
311 /* FreeType API doesn't support vertical kerning */
312 return 0;
313 }
314
315 static hb_bool_t
316 hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED,
317 void *font_data,
318 hb_codepoint_t glyph,
319 hb_glyph_extents_t *extents,
320 void *user_data HB_UNUSED)
321 {
322 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
323 FT_Face ft_face = ft_font->ft_face;
324
325 if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
326 return false;
327
328 extents->x_bearing = ft_face->glyph->metrics.horiBearingX;
329 extents->y_bearing = ft_face->glyph->metrics.horiBearingY;
330 extents->width = ft_face->glyph->metrics.width;
331 extents->height = -ft_face->glyph->metrics.height;
332 return true;
333 }
334
335 static hb_bool_t
336 hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED,
337 void *font_data,
338 hb_codepoint_t glyph,
339 unsigned int point_index,
340 hb_position_t *x,
341 hb_position_t *y,
342 void *user_data HB_UNUSED)
343 {
344 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
345 FT_Face ft_face = ft_font->ft_face;
346
347 if (unlikely (FT_Load_Glyph (ft_face, glyph, ft_font->load_flags)))
348 return false;
349
350 if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE))
351 return false;
352
353 if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points))
354 return false;
355
356 *x = ft_face->glyph->outline.points[point_index].x;
357 *y = ft_face->glyph->outline.points[point_index].y;
358
359 return true;
360 }
361
362 static hb_bool_t
363 hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED,
364 void *font_data,
365 hb_codepoint_t glyph,
366 char *name, unsigned int size,
367 void *user_data HB_UNUSED)
368 {
369 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
370
371 hb_bool_t ret = !FT_Get_Glyph_Name (ft_font->ft_face, glyph, name, size);
372 if (ret && (size && !*name))
373 ret = false;
374
375 return ret;
376 }
377
378 static hb_bool_t
379 hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED,
380 void *font_data,
381 const char *name, int len, /* -1 means nul-terminated */
382 hb_codepoint_t *glyph,
383 void *user_data HB_UNUSED)
384 {
385 const hb_ft_font_t *ft_font = (const hb_ft_font_t *) font_data;
386 FT_Face ft_face = ft_font->ft_face;
387
388 if (len < 0)
389 *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name);
390 else {
391 /* Make a nul-terminated version. */
392 char buf[128];
393 len = MIN (len, (int) sizeof (buf) - 1);
394 strncpy (buf, name, len);
395 buf[len] = '\0';
396 *glyph = FT_Get_Name_Index (ft_face, buf);
397 }
398
399 if (*glyph == 0)
400 {
401 /* Check whether the given name was actually the name of glyph 0. */
402 char buf[128];
403 if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) &&
404 len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len))
405 return true;
406 }
407
408 return *glyph != 0;
409 }
410
411
412 static void
413 _hb_ft_font_set_funcs (hb_font_t *font, FT_Face ft_face, bool unref)
414 {
415 static const hb_font_funcs_t ft_ffuncs = {
416 HB_OBJECT_HEADER_STATIC,
417
418 true, /* immutable */
419
420 {
421 #define HB_FONT_FUNC_IMPLEMENT(name) hb_ft_get_##name,
422 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
423 #undef HB_FONT_FUNC_IMPLEMENT
424 }
425 };
426
427 hb_font_set_funcs (font,
428 const_cast<hb_font_funcs_t *> (&ft_ffuncs),
429 _hb_ft_font_create (ft_face, unref),
430 (hb_destroy_func_t) _hb_ft_font_destroy);
431 }
432
433
434 static hb_blob_t *
435 reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data)
436 {
437 FT_Face ft_face = (FT_Face) user_data;
438 FT_Byte *buffer;
439 FT_ULong length = 0;
440 FT_Error error;
441
442 /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */
443
444 error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length);
445 if (error)
446 return NULL;
447
448 buffer = (FT_Byte *) malloc (length);
449 if (buffer == NULL)
450 return NULL;
451
452 error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length);
453 if (error)
454 return NULL;
455
456 return hb_blob_create ((const char *) buffer, length,
457 HB_MEMORY_MODE_WRITABLE,
458 buffer, free);
459 }
460
461 /**
462 * hb_ft_face_create:
463 * @ft_face: (destroy destroy) (scope notified):
464 * @destroy:
465 *
466 *
467 *
468 * Return value: (transfer full):
469 * Since: 0.9.2
470 **/
471 hb_face_t *
472 hb_ft_face_create (FT_Face ft_face,
473 hb_destroy_func_t destroy)
474 {
475 hb_face_t *face;
476
477 if (ft_face->stream->read == NULL) {
478 hb_blob_t *blob;
479
480 blob = hb_blob_create ((const char *) ft_face->stream->base,
481 (unsigned int) ft_face->stream->size,
482 HB_MEMORY_MODE_READONLY,
483 ft_face, destroy);
484 face = hb_face_create (blob, ft_face->face_index);
485 hb_blob_destroy (blob);
486 } else {
487 face = hb_face_create_for_tables (reference_table, ft_face, destroy);
488 }
489
490 hb_face_set_index (face, ft_face->face_index);
491 hb_face_set_upem (face, ft_face->units_per_EM);
492
493 return face;
494 }
495
496 /**
497 * hb_ft_face_create_referenced:
498 * @ft_face:
499 *
500 *
501 *
502 * Return value: (transfer full):
503 * Since: 0.9.38
504 **/
505 hb_face_t *
506 hb_ft_face_create_referenced (FT_Face ft_face)
507 {
508 FT_Reference_Face (ft_face);
509 return hb_ft_face_create (ft_face, (hb_destroy_func_t) FT_Done_Face);
510 }
511
512 static void
513 hb_ft_face_finalize (FT_Face ft_face)
514 {
515 hb_face_destroy ((hb_face_t *) ft_face->generic.data);
516 }
517
518 /**
519 * hb_ft_face_create_cached:
520 * @ft_face:
521 *
522 *
523 *
524 * Return value: (transfer full):
525 * Since: 0.9.2
526 **/
527 hb_face_t *
528 hb_ft_face_create_cached (FT_Face ft_face)
529 {
530 if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize))
531 {
532 if (ft_face->generic.finalizer)
533 ft_face->generic.finalizer (ft_face);
534
535 ft_face->generic.data = hb_ft_face_create (ft_face, NULL);
536 ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize;
537 }
538
539 return hb_face_reference ((hb_face_t *) ft_face->generic.data);
540 }
541
542
543 /**
544 * hb_ft_font_create:
545 * @ft_face: (destroy destroy) (scope notified):
546 * @destroy:
547 *
548 *
549 *
550 * Return value: (transfer full):
551 * Since: 0.9.2
552 **/
553 hb_font_t *
554 hb_ft_font_create (FT_Face ft_face,
555 hb_destroy_func_t destroy)
556 {
557 hb_font_t *font;
558 hb_face_t *face;
559
560 face = hb_ft_face_create (ft_face, destroy);
561 font = hb_font_create (face);
562 hb_face_destroy (face);
563 _hb_ft_font_set_funcs (font, ft_face, false);
564 hb_font_set_scale (font,
565 (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16),
566 (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16));
567 #if 0 /* hb-ft works in no-hinting model */
568 hb_font_set_ppem (font,
569 ft_face->size->metrics.x_ppem,
570 ft_face->size->metrics.y_ppem);
571 #endif
572
573 return font;
574 }
575
576 /**
577 * hb_ft_font_create_referenced:
578 * @ft_face:
579 *
580 *
581 *
582 * Return value: (transfer full):
583 * Since: 0.9.38
584 **/
585 hb_font_t *
586 hb_ft_font_create_referenced (FT_Face ft_face)
587 {
588 FT_Reference_Face (ft_face);
589 return hb_ft_font_create (ft_face, (hb_destroy_func_t) FT_Done_Face);
590 }
591
592
593 /* Thread-safe, lock-free, FT_Library */
594
595 static FT_Library ft_library;
596
597 #ifdef HB_USE_ATEXIT
598 static
599 void free_ft_library (void)
600 {
601 FT_Done_FreeType (ft_library);
602 }
603 #endif
604
605 static FT_Library
606 get_ft_library (void)
607 {
608 retry:
609 FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library);
610
611 if (unlikely (!library))
612 {
613 /* Not found; allocate one. */
614 if (FT_Init_FreeType (&library))
615 return NULL;
616
617 if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) {
618 FT_Done_FreeType (library);
619 goto retry;
620 }
621
622 #ifdef HB_USE_ATEXIT
623 atexit (free_ft_library); /* First person registers atexit() callback. */
624 #endif
625 }
626
627 return library;
628 }
629
630 static void
631 _release_blob (FT_Face ft_face)
632 {
633 hb_blob_destroy ((hb_blob_t *) ft_face->generic.data);
634 }
635
636 void
637 hb_ft_font_set_funcs (hb_font_t *font)
638 {
639 hb_blob_t *blob = hb_face_reference_blob (font->face);
640 unsigned int blob_length;
641 const char *blob_data = hb_blob_get_data (blob, &blob_length);
642 if (unlikely (!blob_length))
643 DEBUG_MSG (FT, font, "Font face has empty blob");
644
645 FT_Face ft_face = NULL;
646 FT_Error err = FT_New_Memory_Face (get_ft_library (),
647 (const FT_Byte *) blob_data,
648 blob_length,
649 hb_face_get_index (font->face),
650 &ft_face);
651
652 if (unlikely (err)) {
653 hb_blob_destroy (blob);
654 DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed");
655 return;
656 }
657
658 FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE);
659
660 FT_Set_Char_Size (ft_face,
661 abs (font->x_scale), abs (font->y_scale),
662 0, 0);
663 #if 0
664 font->x_ppem * 72 * 64 / font->x_scale,
665 font->y_ppem * 72 * 64 / font->y_scale);
666 #endif
667 if (font->x_scale < 0 || font->y_scale < 0)
668 {
669 FT_Matrix matrix = { font->x_scale < 0 ? -1 : +1, 0,
670 0, font->y_scale < 0 ? -1 : +1};
671 FT_Set_Transform (ft_face, &matrix, NULL);
672 }
673
674 ft_face->generic.data = blob;
675 ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob;
676
677 _hb_ft_font_set_funcs (font, ft_face, true);
678 hb_ft_font_set_load_flags (font, FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING);
679 }