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 gr_face *
hb_graphite2_face_get_gr_face(hb_face_t * face)142 hb_graphite2_face_get_gr_face (hb_face_t *face)
143 {
144 if (unlikely (!hb_graphite2_shaper_face_data_ensure (face))) return NULL;
145 return HB_SHAPER_DATA_GET (face)->grface;
146 }
147
148
149 /*
150 * shaper font data
151 */
152
hb_graphite2_get_advance(const void * hb_font,unsigned short gid)153 static float hb_graphite2_get_advance (const void *hb_font, unsigned short gid)
154 {
155 return ((hb_font_t *) hb_font)->get_glyph_h_advance (gid);
156 }
157
158 hb_graphite2_shaper_font_data_t *
_hb_graphite2_shaper_font_data_create(hb_font_t * font)159 _hb_graphite2_shaper_font_data_create (hb_font_t *font)
160 {
161 if (unlikely (!hb_graphite2_shaper_face_data_ensure (font->face))) return NULL;
162
163 hb_face_t *face = font->face;
164 hb_graphite2_shaper_face_data_t *face_data = HB_SHAPER_DATA_GET (face);
165
166 return gr_make_font_with_advance_fn (font->x_scale, font, &hb_graphite2_get_advance, face_data->grface);
167 }
168
169 void
_hb_graphite2_shaper_font_data_destroy(hb_graphite2_shaper_font_data_t * data)170 _hb_graphite2_shaper_font_data_destroy (hb_graphite2_shaper_font_data_t *data)
171 {
172 gr_font_destroy (data);
173 }
174
175 gr_font *
hb_graphite2_font_get_gr_font(hb_font_t * font)176 hb_graphite2_font_get_gr_font (hb_font_t *font)
177 {
178 if (unlikely (!hb_graphite2_shaper_font_data_ensure (font))) return NULL;
179 return HB_SHAPER_DATA_GET (font);
180 }
181
182
183 /*
184 * shaper shape_plan data
185 */
186
187 struct hb_graphite2_shaper_shape_plan_data_t {};
188
189 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)190 _hb_graphite2_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan HB_UNUSED,
191 const hb_feature_t *user_features HB_UNUSED,
192 unsigned int num_user_features HB_UNUSED)
193 {
194 return (hb_graphite2_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
195 }
196
197 void
_hb_graphite2_shaper_shape_plan_data_destroy(hb_graphite2_shaper_shape_plan_data_t * data HB_UNUSED)198 _hb_graphite2_shaper_shape_plan_data_destroy (hb_graphite2_shaper_shape_plan_data_t *data HB_UNUSED)
199 {
200 }
201
202
203 /*
204 * shaper
205 */
206
207 struct hb_graphite2_cluster_t {
208 unsigned int base_char;
209 unsigned int num_chars;
210 unsigned int base_glyph;
211 unsigned int num_glyphs;
212 unsigned int cluster;
213 };
214
215 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)216 _hb_graphite2_shape (hb_shape_plan_t *shape_plan,
217 hb_font_t *font,
218 hb_buffer_t *buffer,
219 const hb_feature_t *features,
220 unsigned int num_features)
221 {
222 hb_face_t *face = font->face;
223 gr_face *grface = HB_SHAPER_DATA_GET (face)->grface;
224 gr_font *grfont = HB_SHAPER_DATA_GET (font);
225
226 const char *lang = hb_language_to_string (hb_buffer_get_language (buffer));
227 const char *lang_end = lang ? strchr (lang, '-') : NULL;
228 int lang_len = lang_end ? lang_end - lang : -1;
229 gr_feature_val *feats = gr_face_featureval_for_lang (grface, lang ? hb_tag_from_string (lang, lang_len) : 0);
230
231 while (num_features--)
232 {
233 const gr_feature_ref *fref = gr_face_find_fref (grface, features->tag);
234 if (fref)
235 gr_fref_set_feature_value (fref, features->value, feats);
236 features++;
237 }
238
239 gr_segment *seg = NULL;
240 const gr_slot *is;
241 unsigned int ci = 0, ic = 0;
242 float curradvx = 0., curradvy = 0.;
243
244 unsigned int scratch_size;
245 hb_buffer_t::scratch_buffer_t *scratch = buffer->get_scratch_buffer (&scratch_size);
246
247 uint32_t *chars = (uint32_t *) scratch;
248
249 for (unsigned int i = 0; i < buffer->len; ++i)
250 chars[i] = buffer->info[i].codepoint;
251
252 hb_tag_t script_tag[2];
253 hb_ot_tags_from_script (hb_buffer_get_script (buffer), &script_tag[0], &script_tag[1]);
254
255 seg = gr_make_seg (grfont, grface,
256 script_tag[1] == HB_TAG_NONE ? script_tag[0] : script_tag[1],
257 feats,
258 gr_utf32, chars, buffer->len,
259 2 | (hb_buffer_get_direction (buffer) == HB_DIRECTION_RTL ? 1 : 0));
260
261 if (unlikely (!seg)) {
262 if (feats) gr_featureval_destroy (feats);
263 return false;
264 }
265
266 unsigned int glyph_count = gr_seg_n_slots (seg);
267 if (unlikely (!glyph_count)) {
268 if (feats) gr_featureval_destroy (feats);
269 gr_seg_destroy (seg);
270 return false;
271 }
272
273 scratch = buffer->get_scratch_buffer (&scratch_size);
274 while ((DIV_CEIL (sizeof (hb_graphite2_cluster_t) * buffer->len, sizeof (*scratch)) +
275 DIV_CEIL (sizeof (hb_codepoint_t) * glyph_count, sizeof (*scratch))) > scratch_size)
276 {
277 if (unlikely (!buffer->ensure (buffer->allocated * 2)))
278 {
279 if (feats) gr_featureval_destroy (feats);
280 gr_seg_destroy (seg);
281 return false;
282 }
283 scratch = buffer->get_scratch_buffer (&scratch_size);
284 }
285
286 #define ALLOCATE_ARRAY(Type, name, len) \
287 Type *name = (Type *) scratch; \
288 { \
289 unsigned int _consumed = DIV_CEIL ((len) * sizeof (Type), sizeof (*scratch)); \
290 assert (_consumed <= scratch_size); \
291 scratch += _consumed; \
292 scratch_size -= _consumed; \
293 }
294
295 ALLOCATE_ARRAY (hb_graphite2_cluster_t, clusters, buffer->len);
296 ALLOCATE_ARRAY (hb_codepoint_t, gids, glyph_count);
297
298 #undef ALLOCATE_ARRAY
299
300 memset (clusters, 0, sizeof (clusters[0]) * buffer->len);
301
302 hb_codepoint_t *pg = gids;
303 clusters[0].cluster = buffer->info[0].cluster;
304 for (is = gr_seg_first_slot (seg), ic = 0; is; is = gr_slot_next_in_segment (is), ic++)
305 {
306 unsigned int before = gr_slot_before (is);
307 unsigned int after = gr_slot_after (is);
308 *pg = gr_slot_gid (is);
309 pg++;
310 while (clusters[ci].base_char > before && ci)
311 {
312 clusters[ci-1].num_chars += clusters[ci].num_chars;
313 clusters[ci-1].num_glyphs += clusters[ci].num_glyphs;
314 ci--;
315 }
316
317 if (gr_slot_can_insert_before (is) && clusters[ci].num_chars && before >= clusters[ci].base_char + clusters[ci].num_chars)
318 {
319 hb_graphite2_cluster_t *c = clusters + ci + 1;
320 c->base_char = clusters[ci].base_char + clusters[ci].num_chars;
321 c->cluster = buffer->info[c->base_char].cluster;
322 c->num_chars = before - c->base_char;
323 c->base_glyph = ic;
324 c->num_glyphs = 0;
325 ci++;
326 }
327 clusters[ci].num_glyphs++;
328
329 if (clusters[ci].base_char + clusters[ci].num_chars < after + 1)
330 clusters[ci].num_chars = after + 1 - clusters[ci].base_char;
331 }
332 ci++;
333
334 //buffer->clear_output ();
335 for (unsigned int i = 0; i < ci; ++i)
336 {
337 for (unsigned int j = 0; j < clusters[i].num_glyphs; ++j)
338 {
339 hb_glyph_info_t *info = &buffer->info[clusters[i].base_glyph + j];
340 info->codepoint = gids[clusters[i].base_glyph + j];
341 info->cluster = clusters[i].cluster;
342 }
343 }
344 buffer->len = glyph_count;
345 //buffer->swap_buffers ();
346
347 if (HB_DIRECTION_IS_BACKWARD(buffer->props.direction))
348 curradvx = gr_seg_advance_X(seg);
349
350 hb_glyph_position_t *pPos;
351 for (pPos = hb_buffer_get_glyph_positions (buffer, NULL), is = gr_seg_first_slot (seg);
352 is; pPos++, is = gr_slot_next_in_segment (is))
353 {
354 pPos->x_offset = gr_slot_origin_X (is) - curradvx;
355 pPos->y_offset = gr_slot_origin_Y (is) - curradvy;
356 pPos->x_advance = gr_slot_advance_X (is, grface, grfont);
357 pPos->y_advance = gr_slot_advance_Y (is, grface, grfont);
358 if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
359 curradvx -= pPos->x_advance;
360 pPos->x_offset = gr_slot_origin_X (is) - curradvx;
361 if (!HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
362 curradvx += pPos->x_advance;
363 pPos->y_offset = gr_slot_origin_Y (is) - curradvy;
364 curradvy += pPos->y_advance;
365 }
366 if (!HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
367 pPos[-1].x_advance += gr_seg_advance_X(seg) - curradvx;
368
369 if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
370 hb_buffer_reverse_clusters (buffer);
371
372 if (feats) gr_featureval_destroy (feats);
373 gr_seg_destroy (seg);
374
375 return true;
376 }
377