1/*
2 * Copyright © 2011 Martin Hosken
3 * Copyright © 2011 SIL International
4 * Copyright © 2011,2012 Google, Inc.
5 *
6 * This is part of HarfBuzz, a text shaping library.
7 *
8 * Permission is hereby granted, without written agreement and without
9 * license or royalty fees, to use, copy, modify, and distribute this
10 * software and its documentation for any purpose, provided that the
11 * above copyright notice and the following two paragraphs appear in
12 * all copies of this software.
13 *
14 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
15 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
17 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
18 * DAMAGE.
19 *
20 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
21 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
22 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
23 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
24 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
25 *
26 * Google Author(s): Behdad Esfahbod
27 */
28
29#include "hb.hh"
30
31#ifdef HAVE_GRAPHITE2
32
33#include "hb-shaper-impl.hh"
34
35#include "hb-graphite2.h"
36
37#include <graphite2/Segment.h>
38
39#include "hb-ot-layout.h"
40
41
42/**
43 * SECTION:hb-graphite2
44 * @title: hb-graphite2
45 * @short_description: Graphite2 integration
46 * @include: hb-graphite2.h
47 *
48 * Functions for using HarfBuzz with the Graphite2 fonts.
49 **/
50
51
52/*
53 * shaper face data
54 */
55
56typedef struct hb_graphite2_tablelist_t
57{
58 struct hb_graphite2_tablelist_t *next;
59 hb_blob_t *blob;
60 unsigned int tag;
61} hb_graphite2_tablelist_t;
62
63struct hb_graphite2_face_data_t
64{
65 hb_face_t *face;
66 gr_face *grface;
67 hb_atomic_ptr_t<hb_graphite2_tablelist_t> tlist;
68};
69
70static const void *hb_graphite2_get_table (const void *data, unsigned int tag, size_t *len)
71{
72 hb_graphite2_face_data_t *face_data = (hb_graphite2_face_data_t *) data;
73 hb_graphite2_tablelist_t *tlist = face_data->tlist;
74
75 hb_blob_t *blob = nullptr;
76
77 for (hb_graphite2_tablelist_t *p = tlist; p; p = p->next)
78 if (p->tag == tag) {
79 blob = p->blob;
80 break;
81 }
82
83 if (unlikely (!blob))
84 {
85 blob = face_data->face->reference_table (tag);
86
87 hb_graphite2_tablelist_t *p = (hb_graphite2_tablelist_t *) calloc (1, sizeof (hb_graphite2_tablelist_t));
88 if (unlikely (!p)) {
89 hb_blob_destroy (blob);
90 return nullptr;
91 }
92 p->blob = blob;
93 p->tag = tag;
94
95retry:
96 hb_graphite2_tablelist_t *tlist = face_data->tlist;
97 p->next = tlist;
98
99 if (unlikely (!face_data->tlist.cmpexch (tlist, p)))
100 goto retry;
101 }
102
103 unsigned int tlen;
104 const char *d = hb_blob_get_data (blob, &tlen);
105 *len = tlen;
106 return d;
107}
108
109hb_graphite2_face_data_t *
110_hb_graphite2_shaper_face_data_create (hb_face_t *face)
111{
112 hb_blob_t *silf_blob = face->reference_table (HB_GRAPHITE2_TAG_SILF);
113 /* Umm, we just reference the table to check whether it exists.
114 * Maybe add better API for this? */
115 if (!hb_blob_get_length (silf_blob))
116 {
117 hb_blob_destroy (silf_blob);
118 return nullptr;
119 }
120 hb_blob_destroy (silf_blob);
121
122 hb_graphite2_face_data_t *data = (hb_graphite2_face_data_t *) calloc (1, sizeof (hb_graphite2_face_data_t));
123 if (unlikely (!data))
124 return nullptr;
125
126 data->face = face;
127 data->grface = gr_make_face (data, &hb_graphite2_get_table, gr_face_preloadAll);
128
129 if (unlikely (!data->grface)) {
130 free (data);
131 return nullptr;
132 }
133
134 return data;
135}
136
137void
138_hb_graphite2_shaper_face_data_destroy (hb_graphite2_face_data_t *data)
139{
140 hb_graphite2_tablelist_t *tlist = data->tlist;
141
142 while (tlist)
143 {
144 hb_graphite2_tablelist_t *old = tlist;
145 hb_blob_destroy (tlist->blob);
146 tlist = tlist->next;
147 free (old);
148 }
149
150 gr_face_destroy (data->grface);
151
152 free (data);
153}
154
155/*
156 * Since: 0.9.10
157 */
158gr_face *
159hb_graphite2_face_get_gr_face (hb_face_t *face)
160{
161 const hb_graphite2_face_data_t *data = face->data.graphite2;
162 return data ? data->grface : nullptr;
163}
164
165
166/*
167 * shaper font data
168 */
169
170struct hb_graphite2_font_data_t {};
171
172hb_graphite2_font_data_t *
173_hb_graphite2_shaper_font_data_create (hb_font_t *font HB_UNUSED)
174{
175 return (hb_graphite2_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
176}
177
178void
179_hb_graphite2_shaper_font_data_destroy (hb_graphite2_font_data_t *data HB_UNUSED)
180{
181}
182
183#ifndef HB_DISABLE_DEPRECATED
184/**
185 * hb_graphite2_font_get_gr_font:
186 *
187 * Since: 0.9.10
188 * Deprecated: 1.4.2
189 */
190gr_font *
191hb_graphite2_font_get_gr_font (hb_font_t *font HB_UNUSED)
192{
193 return nullptr;
194}
195#endif
196
197
198/*
199 * shaper
200 */
201
202struct hb_graphite2_cluster_t {
203 unsigned int base_char;
204 unsigned int num_chars;
205 unsigned int base_glyph;
206 unsigned int num_glyphs;
207 unsigned int cluster;
208 unsigned int advance;
209};
210
211hb_bool_t
212_hb_graphite2_shape (hb_shape_plan_t *shape_plan HB_UNUSED,
213 hb_font_t *font,
214 hb_buffer_t *buffer,
215 const hb_feature_t *features,
216 unsigned int num_features)
217{
218 hb_face_t *face = font->face;
219 gr_face *grface = face->data.graphite2->grface;
220
221 const char *lang = hb_language_to_string (hb_buffer_get_language (buffer));
222 const char *lang_end = lang ? strchr (lang, '-') : nullptr;
223 int lang_len = lang_end ? lang_end - lang : -1;
224 gr_feature_val *feats = gr_face_featureval_for_lang (grface, lang ? hb_tag_from_string (lang, lang_len) : 0);
225
226 for (unsigned int i = 0; i < num_features; i++)
227 {
228 const gr_feature_ref *fref = gr_face_find_fref (grface, features[i].tag);
229 if (fref)
230 gr_fref_set_feature_value (fref, features[i].value, feats);
231 }
232
233 gr_segment *seg = nullptr;
234 const gr_slot *is;
235 unsigned int ci = 0, ic = 0;
236 unsigned int curradvx = 0, curradvy = 0;
237
238 unsigned int scratch_size;
239 hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
240
241 uint32_t *chars = (uint32_t *) scratch;
242
243 for (unsigned int i = 0; i < buffer->len; ++i)
244 chars[i] = buffer->info[i].codepoint;
245
246 /* TODO ensure_native_direction. */
247
248 hb_tag_t script_tag[HB_OT_MAX_TAGS_PER_SCRIPT];
249 unsigned int count = HB_OT_MAX_TAGS_PER_SCRIPT;
250 hb_ot_tags_from_script_and_language (hb_buffer_get_script (buffer),
251 HB_LANGUAGE_INVALID,
252 &count,
253 script_tag,
254 nullptr, nullptr);
255
256 seg = gr_make_seg (nullptr, grface,
257 count ? script_tag[count - 1] : HB_OT_TAG_DEFAULT_SCRIPT,
258 feats,
259 gr_utf32, chars, buffer->len,
260 2 | (hb_buffer_get_direction (buffer) == HB_DIRECTION_RTL ? 1 : 0));
261
262 if (unlikely (!seg)) {
263 if (feats) gr_featureval_destroy (feats);
264 return false;
265 }
266
267 unsigned int glyph_count = gr_seg_n_slots (seg);
268 if (unlikely (!glyph_count)) {
269 if (feats) gr_featureval_destroy (feats);
270 gr_seg_destroy (seg);
271 buffer->len = 0;
272 return true;
273 }
274
275 buffer->ensure (glyph_count);
276 scratch = buffer->get_scratch_buffer (&scratch_size);
277 while ((DIV_CEIL (sizeof (hb_graphite2_cluster_t) * buffer->len, sizeof (*scratch)) +
278 DIV_CEIL (sizeof (hb_codepoint_t) * glyph_count, sizeof (*scratch))) > scratch_size)
279 {
280 if (unlikely (!buffer->ensure (buffer->allocated * 2)))
281 {
282 if (feats) gr_featureval_destroy (feats);
283 gr_seg_destroy (seg);
284 return false;
285 }
286 scratch = buffer->get_scratch_buffer (&scratch_size);
287 }
288
289#define ALLOCATE_ARRAY(Type, name, len) \
290 Type *name = (Type *) scratch; \
291 do { \
292 unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
293 assert (_consumed <= scratch_size); \
294 scratch += _consumed; \
295 scratch_size -= _consumed; \
296 } while (0)
297
298 ALLOCATE_ARRAY (hb_graphite2_cluster_t, clusters, buffer->len);
299 ALLOCATE_ARRAY (hb_codepoint_t, gids, glyph_count);
300
301#undef ALLOCATE_ARRAY
302
303 memset (clusters, 0, sizeof (clusters[0]) * buffer->len);
304
305 hb_codepoint_t *pg = gids;
306 clusters[0].cluster = buffer->info[0].cluster;
307 unsigned int upem = hb_face_get_upem (face);
308 float xscale = (float) font->x_scale / upem;
309 float yscale = (float) font->y_scale / upem;
310 yscale *= yscale / xscale;
311 unsigned int curradv = 0;
312 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
313 {
314 curradv = gr_slot_origin_X(gr_seg_first_slot(seg)) * xscale;
315 clusters[0].advance = gr_seg_advance_X(seg) * xscale - curradv;
316 }
317 else
318 clusters[0].advance = 0;
319 for (is = gr_seg_first_slot (seg), ic = 0; is; is = gr_slot_next_in_segment (is), ic++)
320 {
321 unsigned int before = gr_slot_before (is);
322 unsigned int after = gr_slot_after (is);
323 *pg = gr_slot_gid (is);
324 pg++;
325 while (clusters[ci].base_char > before && ci)
326 {
327 clusters[ci-1].num_chars += clusters[ci].num_chars;
328 clusters[ci-1].num_glyphs += clusters[ci].num_glyphs;
329 clusters[ci-1].advance += clusters[ci].advance;
330 ci--;
331 }
332
333 if (gr_slot_can_insert_before (is) && clusters[ci].num_chars && before >= clusters[ci].base_char + clusters[ci].num_chars)
334 {
335 hb_graphite2_cluster_t *c = clusters + ci + 1;
336 c->base_char = clusters[ci].base_char + clusters[ci].num_chars;
337 c->cluster = buffer->info[c->base_char].cluster;
338 c->num_chars = before - c->base_char;
339 c->base_glyph = ic;
340 c->num_glyphs = 0;
341 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
342 {
343 c->advance = curradv - gr_slot_origin_X(is) * xscale;
344 curradv -= c->advance;
345 }
346 else
347 {
348 c->advance = 0;
349 clusters[ci].advance += gr_slot_origin_X(is) * xscale - curradv;
350 curradv += clusters[ci].advance;
351 }
352 ci++;
353 }
354 clusters[ci].num_glyphs++;
355
356 if (clusters[ci].base_char + clusters[ci].num_chars < after + 1)
357 clusters[ci].num_chars = after + 1 - clusters[ci].base_char;
358 }
359
360 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
361 clusters[ci].advance += curradv;
362 else
363 clusters[ci].advance += gr_seg_advance_X(seg) * xscale - curradv;
364 ci++;
365
366 for (unsigned int i = 0; i < ci; ++i)
367 {
368 for (unsigned int j = 0; j < clusters[i].num_glyphs; ++j)
369 {
370 hb_glyph_info_t *info = &buffer->info[clusters[i].base_glyph + j];
371 info->codepoint = gids[clusters[i].base_glyph + j];
372 info->cluster = clusters[i].cluster;
373 info->var1.i32 = clusters[i].advance; // all glyphs in the cluster get the same advance
374 }
375 }
376 buffer->len = glyph_count;
377
378 /* Positioning. */
379 unsigned int currclus = (unsigned int) -1;
380 const hb_glyph_info_t *info = buffer->info;
381 hb_glyph_position_t *pPos = hb_buffer_get_glyph_positions (buffer, nullptr);
382 if (!HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
383 {
384 curradvx = 0;
385 for (is = gr_seg_first_slot (seg); is; pPos++, ++info, is = gr_slot_next_in_segment (is))
386 {
387 pPos->x_offset = gr_slot_origin_X (is) * xscale - curradvx;
388 pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
389 if (info->cluster != currclus) {
390 pPos->x_advance = info->var1.i32;
391 curradvx += pPos->x_advance;
392 currclus = info->cluster;
393 } else
394 pPos->x_advance = 0.;
395
396 pPos->y_advance = gr_slot_advance_Y (is, grface, nullptr) * yscale;
397 curradvy += pPos->y_advance;
398 }
399 }
400 else
401 {
402 curradvx = gr_seg_advance_X(seg) * xscale;
403 for (is = gr_seg_first_slot (seg); is; pPos++, info++, is = gr_slot_next_in_segment (is))
404 {
405 if (info->cluster != currclus)
406 {
407 pPos->x_advance = info->var1.i32;
408 curradvx -= pPos->x_advance;
409 currclus = info->cluster;
410 } else
411 pPos->x_advance = 0.;
412
413 pPos->y_advance = gr_slot_advance_Y (is, grface, nullptr) * yscale;
414 curradvy -= pPos->y_advance;
415 pPos->x_offset = gr_slot_origin_X (is) * xscale - info->var1.i32 - curradvx + pPos->x_advance;
416 pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
417 }
418 hb_buffer_reverse_clusters (buffer);
419 }
420
421 if (feats) gr_featureval_destroy (feats);
422 gr_seg_destroy (seg);
423
424 buffer->unsafe_to_break_all ();
425
426 return true;
427}
428
429
430#endif
431