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 #define HB_SHAPER graphite2
30 #define hb_graphite2_shaper_font_data_t gr_font
31 #include "hb-shaper-impl-private.hh"
32
33 #include "hb-graphite2.h"
34
35 #include <graphite2/Segment.h>
36
37
38 HB_SHAPER_DATA_ENSURE_DECLARE(graphite2, face)
39 HB_SHAPER_DATA_ENSURE_DECLARE(graphite2, font)
40
41
42 /*
43 * shaper face data
44 */
45
46 typedef struct hb_graphite2_tablelist_t {
47 struct hb_graphite2_tablelist_t *next;
48 hb_blob_t *blob;
49 unsigned int tag;
50 } hb_graphite2_tablelist_t;
51
52 struct hb_graphite2_shaper_face_data_t {
53 hb_face_t *face;
54 gr_face *grface;
55 hb_graphite2_tablelist_t *tlist;
56 };
57
hb_graphite2_get_table(const void * data,unsigned int tag,size_t * len)58 static const void *hb_graphite2_get_table (const void *data, unsigned int tag, size_t *len)
59 {
60 hb_graphite2_shaper_face_data_t *face_data = (hb_graphite2_shaper_face_data_t *) data;
61 hb_graphite2_tablelist_t *tlist = face_data->tlist;
62
63 hb_blob_t *blob = NULL;
64
65 for (hb_graphite2_tablelist_t *p = tlist; p; p = p->next)
66 if (p->tag == tag) {
67 blob = p->blob;
68 break;
69 }
70
71 if (unlikely (!blob))
72 {
73 blob = face_data->face->reference_table (tag);
74
75 hb_graphite2_tablelist_t *p = (hb_graphite2_tablelist_t *) calloc (1, sizeof (hb_graphite2_tablelist_t));
76 if (unlikely (!p)) {
77 hb_blob_destroy (blob);
78 return NULL;
79 }
80 p->blob = blob;
81 p->tag = tag;
82
83 /* TODO Not thread-safe, but fairly harmless.
84 * We can do the double-chcked pointer cmpexch thing here. */
85 p->next = face_data->tlist;
86 face_data->tlist = p;
87 }
88
89 unsigned int tlen;
90 const char *d = hb_blob_get_data (blob, &tlen);
91 *len = tlen;
92 return d;
93 }
94
95 hb_graphite2_shaper_face_data_t *
_hb_graphite2_shaper_face_data_create(hb_face_t * face)96 _hb_graphite2_shaper_face_data_create (hb_face_t *face)
97 {
98 hb_blob_t *silf_blob = face->reference_table (HB_GRAPHITE2_TAG_SILF);
99 /* Umm, we just reference the table to check whether it exists.
100 * Maybe add better API for this? */
101 if (!hb_blob_get_length (silf_blob))
102 {
103 hb_blob_destroy (silf_blob);
104 return NULL;
105 }
106 hb_blob_destroy (silf_blob);
107
108 hb_graphite2_shaper_face_data_t *data = (hb_graphite2_shaper_face_data_t *) calloc (1, sizeof (hb_graphite2_shaper_face_data_t));
109 if (unlikely (!data))
110 return NULL;
111
112 data->face = face;
113 data->grface = gr_make_face (data, &hb_graphite2_get_table, gr_face_preloadAll);
114
115 if (unlikely (!data->grface)) {
116 free (data);
117 return NULL;
118 }
119
120 return data;
121 }
122
123 void
_hb_graphite2_shaper_face_data_destroy(hb_graphite2_shaper_face_data_t * data)124 _hb_graphite2_shaper_face_data_destroy (hb_graphite2_shaper_face_data_t *data)
125 {
126 hb_graphite2_tablelist_t *tlist = data->tlist;
127
128 while (tlist)
129 {
130 hb_graphite2_tablelist_t *old = tlist;
131 hb_blob_destroy (tlist->blob);
132 tlist = tlist->next;
133 free (old);
134 }
135
136 gr_face_destroy (data->grface);
137
138 free (data);
139 }
140
141 /*
142 * Since: 0.9.10
143 */
144 gr_face *
hb_graphite2_face_get_gr_face(hb_face_t * face)145 hb_graphite2_face_get_gr_face (hb_face_t *face)
146 {
147 if (unlikely (!hb_graphite2_shaper_face_data_ensure (face))) return NULL;
148 return HB_SHAPER_DATA_GET (face)->grface;
149 }
150
151
152 /*
153 * shaper font data
154 */
155
hb_graphite2_get_advance(const void * hb_font,unsigned short gid)156 static float hb_graphite2_get_advance (const void *hb_font, unsigned short gid)
157 {
158 return ((hb_font_t *) hb_font)->get_glyph_h_advance (gid);
159 }
160
161 hb_graphite2_shaper_font_data_t *
_hb_graphite2_shaper_font_data_create(hb_font_t * font)162 _hb_graphite2_shaper_font_data_create (hb_font_t *font)
163 {
164 if (unlikely (!hb_graphite2_shaper_face_data_ensure (font->face))) return NULL;
165
166 hb_face_t *face = font->face;
167 hb_graphite2_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
168
169 return gr_make_font_with_advance_fn (font->x_scale, font, &hb_graphite2_get_advance, face_data->grface);
170 }
171
172 void
_hb_graphite2_shaper_font_data_destroy(hb_graphite2_shaper_font_data_t * data)173 _hb_graphite2_shaper_font_data_destroy (hb_graphite2_shaper_font_data_t *data)
174 {
175 gr_font_destroy (data);
176 }
177
178 /*
179 * Since: 0.9.10
180 */
181 gr_font *
hb_graphite2_font_get_gr_font(hb_font_t * font)182 hb_graphite2_font_get_gr_font (hb_font_t *font)
183 {
184 if (unlikely (!hb_graphite2_shaper_font_data_ensure (font))) return NULL;
185 return HB_SHAPER_DATA_GET (font);
186 }
187
188
189 /*
190 * shaper shape_plan data
191 */
192
193 struct hb_graphite2_shaper_shape_plan_data_t {};
194
195 hb_graphite2_shaper_shape_plan_data_t *
_hb_graphite2_shaper_shape_plan_data_create(hb_shape_plan_t * shape_plan HB_UNUSED,const hb_feature_t * user_features HB_UNUSED,unsigned int num_user_features HB_UNUSED,const int * coords HB_UNUSED,unsigned int num_coords HB_UNUSED)196 _hb_graphite2_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan HB_UNUSED,
197 const hb_feature_t *user_features HB_UNUSED,
198 unsigned int num_user_features HB_UNUSED,
199 const int *coords HB_UNUSED,
200 unsigned int num_coords HB_UNUSED)
201 {
202 return (hb_graphite2_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
203 }
204
205 void
_hb_graphite2_shaper_shape_plan_data_destroy(hb_graphite2_shaper_shape_plan_data_t * data HB_UNUSED)206 _hb_graphite2_shaper_shape_plan_data_destroy (hb_graphite2_shaper_shape_plan_data_t *data HB_UNUSED)
207 {
208 }
209
210
211 /*
212 * shaper
213 */
214
215 struct hb_graphite2_cluster_t {
216 unsigned int base_char;
217 unsigned int num_chars;
218 unsigned int base_glyph;
219 unsigned int num_glyphs;
220 unsigned int cluster;
221 float advance;
222 };
223
224 hb_bool_t
_hb_graphite2_shape(hb_shape_plan_t * shape_plan,hb_font_t * font,hb_buffer_t * buffer,const hb_feature_t * features,unsigned int num_features)225 _hb_graphite2_shape (hb_shape_plan_t *shape_plan,
226 hb_font_t *font,
227 hb_buffer_t *buffer,
228 const hb_feature_t *features,
229 unsigned int num_features)
230 {
231 hb_face_t *face = font->face;
232 gr_face *grface = HB_SHAPER_DATA_GET (face)->grface;
233 gr_font *grfont = HB_SHAPER_DATA_GET (font);
234
235 const char *lang = hb_language_to_string (hb_buffer_get_language (buffer));
236 const char *lang_end = lang ? strchr (lang, '-') : NULL;
237 int lang_len = lang_end ? lang_end - lang : -1;
238 gr_feature_val *feats = gr_face_featureval_for_lang (grface, lang ? hb_tag_from_string (lang, lang_len) : 0);
239
240 for (unsigned int i = 0; i < num_features; i++)
241 {
242 const gr_feature_ref *fref = gr_face_find_fref (grface, features[i].tag);
243 if (fref)
244 gr_fref_set_feature_value (fref, features[i].value, feats);
245 }
246
247 gr_segment *seg = NULL;
248 const gr_slot *is;
249 unsigned int ci = 0, ic = 0;
250 float curradvx = 0., curradvy = 0.;
251
252 unsigned int scratch_size;
253 hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
254
255 uint32_t *chars = (uint32_t *) scratch;
256
257 for (unsigned int i = 0; i < buffer->len; ++i)
258 chars[i] = buffer->info[i].codepoint;
259
260 /* TODO ensure_native_direction. */
261
262 hb_tag_t script_tag[2];
263 hb_ot_tags_from_script (hb_buffer_get_script (buffer), &script_tag[0], &script_tag[1]);
264
265 seg = gr_make_seg (grfont, grface,
266 script_tag[1] == HB_TAG_NONE ? script_tag[0] : script_tag[1],
267 feats,
268 gr_utf32, chars, buffer->len,
269 2 | (hb_buffer_get_direction (buffer) == HB_DIRECTION_RTL ? 1 : 0));
270
271 if (unlikely (!seg)) {
272 if (feats) gr_featureval_destroy (feats);
273 return false;
274 }
275
276 unsigned int glyph_count = gr_seg_n_slots (seg);
277 if (unlikely (!glyph_count)) {
278 if (feats) gr_featureval_destroy (feats);
279 gr_seg_destroy (seg);
280 buffer->len = 0;
281 return true;
282 }
283
284 buffer->ensure (glyph_count);
285 scratch = buffer->get_scratch_buffer (&scratch_size);
286 while ((DIV_CEIL (sizeof (hb_graphite2_cluster_t) * buffer->len, sizeof (*scratch)) +
287 DIV_CEIL (sizeof (hb_codepoint_t) * glyph_count, sizeof (*scratch))) > scratch_size)
288 {
289 if (unlikely (!buffer->ensure (buffer->allocated * 2)))
290 {
291 if (feats) gr_featureval_destroy (feats);
292 gr_seg_destroy (seg);
293 return false;
294 }
295 scratch = buffer->get_scratch_buffer (&scratch_size);
296 }
297
298 #define ALLOCATE_ARRAY(Type, name, len) \
299 Type *name = (Type *) scratch; \
300 { \
301 unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
302 assert (_consumed <= scratch_size); \
303 scratch += _consumed; \
304 scratch_size -= _consumed; \
305 }
306
307 ALLOCATE_ARRAY (hb_graphite2_cluster_t, clusters, buffer->len);
308 ALLOCATE_ARRAY (hb_codepoint_t, gids, glyph_count);
309
310 #undef ALLOCATE_ARRAY
311
312 memset (clusters, 0, sizeof (clusters[0]) * buffer->len);
313
314 hb_codepoint_t *pg = gids;
315 clusters[0].cluster = buffer->info[0].cluster;
316 float curradv = HB_DIRECTION_IS_BACKWARD(buffer->props.direction) ? gr_slot_origin_X(gr_seg_first_slot(seg)) : 0.;
317 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
318 {
319 curradv = gr_slot_origin_X(gr_seg_first_slot(seg));
320 clusters[0].advance = gr_seg_advance_X(seg) - curradv;
321 }
322 for (is = gr_seg_first_slot (seg), ic = 0; is; is = gr_slot_next_in_segment (is), ic++)
323 {
324 unsigned int before = gr_slot_before (is);
325 unsigned int after = gr_slot_after (is);
326 *pg = gr_slot_gid (is);
327 pg++;
328 while (clusters[ci].base_char > before && ci)
329 {
330 clusters[ci-1].num_chars += clusters[ci].num_chars;
331 clusters[ci-1].num_glyphs += clusters[ci].num_glyphs;
332 clusters[ci-1].advance += clusters[ci].advance;
333 ci--;
334 }
335
336 if (gr_slot_can_insert_before (is) && clusters[ci].num_chars && before >= clusters[ci].base_char + clusters[ci].num_chars)
337 {
338 hb_graphite2_cluster_t *c = clusters + ci + 1;
339 c->base_char = clusters[ci].base_char + clusters[ci].num_chars;
340 c->cluster = buffer->info[c->base_char].cluster;
341 c->num_chars = before - c->base_char;
342 c->base_glyph = ic;
343 c->num_glyphs = 0;
344 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
345 {
346 ci++;
347 clusters[ci].advance = curradv - gr_slot_origin_X(is);
348 } else {
349 clusters[ci].advance = gr_slot_origin_X(is) - curradv;
350 ci++;
351 }
352 curradv = gr_slot_origin_X(is);
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 = gr_seg_advance_X(seg) - curradv;
362 ci++;
363
364 for (unsigned int i = 0; i < ci; ++i)
365 {
366 for (unsigned int j = 0; j < clusters[i].num_glyphs; ++j)
367 {
368 hb_glyph_info_t *info = &buffer->info[clusters[i].base_glyph + j];
369 info->codepoint = gids[clusters[i].base_glyph + j];
370 info->cluster = clusters[i].cluster;
371 info->var1.i32 = clusters[i].advance; // all glyphs in the cluster get the same advance
372 }
373 }
374 buffer->len = glyph_count;
375
376 float yscale = font->y_scale / font->x_scale;
377 /* Positioning. */
378 if (!HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
379 {
380 int currclus = -1;
381 const hb_glyph_info_t *info = buffer->info;
382 hb_glyph_position_t *pPos = hb_buffer_get_glyph_positions (buffer, NULL);
383 curradvx = 0;
384 for (is = gr_seg_first_slot (seg); is; pPos++, ++info, is = gr_slot_next_in_segment (is))
385 {
386 pPos->x_offset = gr_slot_origin_X (is) - curradvx;
387 pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
388 if (info->cluster != currclus) {
389 pPos->x_advance = info->var1.i32;
390 curradvx += pPos->x_advance;
391 currclus = info->cluster;
392 } else
393 pPos->x_advance = 0.;
394
395 pPos->y_advance = gr_slot_advance_Y (is, grface, grfont) * yscale;
396 curradvy += pPos->y_advance;
397 }
398 }
399 else
400 {
401 int currclus = -1;
402 const hb_glyph_info_t *info = buffer->info;
403 hb_glyph_position_t *pPos = hb_buffer_get_glyph_positions (buffer, NULL);
404 curradvx = gr_seg_advance_X(seg);
405 for (is = gr_seg_first_slot (seg); is; pPos++, info++, is = gr_slot_next_in_segment (is))
406 {
407 if (info->cluster != currclus)
408 {
409 pPos->x_advance = info->var1.i32;
410 if (currclus != -1) curradvx -= info[-1].var1.i32;
411 currclus = info->cluster;
412 } else
413 pPos->x_advance = 0.;
414
415 pPos->y_advance = gr_slot_advance_Y (is, grface, grfont) * yscale;
416 curradvy -= pPos->y_advance;
417 pPos->x_offset = gr_slot_origin_X (is) - curradvx + pPos->x_advance;
418 pPos->y_offset = gr_slot_origin_Y (is) * yscale - curradvy;
419 }
420 hb_buffer_reverse_clusters (buffer);
421 }
422
423 if (feats) gr_featureval_destroy (feats);
424 gr_seg_destroy (seg);
425
426 return true;
427 }
428