1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
|
/* Pango
* hebrew-fc.h: Hebrew shaper for FreeType-based backends
*
* Copyright (C) 2000 Red Hat Software
* Author: Owen Taylor <otaylor@redhat.com>
* Dov Grobgeld <dov.grobgeld@weizmann.ac.il> OpenType support.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include <string.h>
#include <pango/pango-ot.h>
#include "pango-engine.h"
#include "pango-utils.h"
#include "pangofc-font.h"
#include "hebrew-shaper.h"
/* No extra fields needed */
typedef PangoEngineShape HebrewEngineFc;
typedef PangoEngineShapeClass HebrewEngineFcClass ;
#define MAX_CLUSTER_CHRS 20
static PangoEngineScriptInfo hebrew_scripts[] = {
{ PANGO_SCRIPT_HEBREW, "*" }
};
#define SCRIPT_ENGINE_NAME "HebrewScriptEngineFc"
#define RENDER_TYPE PANGO_RENDER_TYPE_FC
static PangoEngineInfo script_engines[] = {
{
SCRIPT_ENGINE_NAME,
PANGO_ENGINE_TYPE_SHAPE,
RENDER_TYPE,
hebrew_scripts, G_N_ELEMENTS(hebrew_scripts)
}
};
static void
get_cluster_glyphs(PangoFont *font,
gunichar cluster[],
gint cluster_size,
gboolean do_mirror,
/* output */
gint glyph_num[],
PangoGlyph glyph[],
gint widths[],
PangoRectangle ink_rects[])
{
int i;
for (i=0; i<cluster_size; i++)
{
PangoRectangle logical_rect;
gunichar wc = cluster[i];
gunichar mirrored_ch;
if (do_mirror)
if (pango_get_mirror_char (wc, &mirrored_ch))
wc = mirrored_ch;
if (pango_is_zero_width (wc))
glyph_num[i] = PANGO_GLYPH_EMPTY;
else
{
glyph_num[i] = pango_fc_font_get_glyph ((PangoFcFont *)font, wc);
if (!glyph_num[i])
glyph_num[i] = PANGO_GET_UNKNOWN_GLYPH ( wc);
}
glyph[i] = glyph_num[i];
pango_font_get_glyph_extents (font,
glyph[i], &ink_rects[i], &logical_rect);
/* Assign the base char width to the last character in the cluster */
if (i==0)
{
widths[i] = 0;
widths[cluster_size-1] = logical_rect.width;
}
else if (i < cluster_size-1)
widths[i] = 0;
}
}
static void
add_glyph (PangoGlyphString *glyphs,
gint cluster_start,
PangoGlyph glyph,
gboolean is_combining,
gint width,
gint x_offset,
gint y_offset
)
{
gint index = glyphs->num_glyphs;
pango_glyph_string_set_size (glyphs, index + 1);
glyphs->glyphs[index].glyph = glyph;
glyphs->glyphs[index].attr.is_cluster_start = is_combining ? 0 : 1;
glyphs->log_clusters[index] = cluster_start;
glyphs->glyphs[index].geometry.x_offset = x_offset;
glyphs->glyphs[index].geometry.y_offset = y_offset;
glyphs->glyphs[index].geometry.width = width;
}
static void
add_cluster(PangoFont *font,
PangoGlyphString *glyphs,
int cluster_size,
int cluster_start,
int glyph_num[],
PangoGlyph glyph[],
int width[],
int x_offset[],
int y_offset[])
{
int i;
for (i=0; i<cluster_size; i++)
{
add_glyph (glyphs, cluster_start, glyph[i],
i == 0 ? FALSE : TRUE, width[i], x_offset[i], y_offset[i]);
}
}
static void
maybe_add_gsub_feature (PangoOTRuleset *ruleset,
PangoOTInfo *info,
guint script_index,
PangoOTTag tag,
gulong property_bit)
{
guint feature_index;
/* 0xffff == default language system */
if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GSUB,
tag, script_index, 0xffff, &feature_index))
pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GSUB, feature_index,
property_bit);
}
static void
maybe_add_gpos_feature (PangoOTRuleset *ruleset,
PangoOTInfo *info,
guint script_index,
PangoOTTag tag,
gulong property_bit)
{
guint feature_index;
/* 0xffff == default language system */
if (pango_ot_info_find_feature (info, PANGO_OT_TABLE_GPOS,
tag, script_index, 0xffff, &feature_index))
pango_ot_ruleset_add_feature (ruleset, PANGO_OT_TABLE_GPOS, feature_index,
property_bit);
}
static PangoOTRuleset *
get_ruleset (FT_Face face)
{
PangoOTRuleset *ruleset;
static GQuark ruleset_quark = 0;
static const PangoOTTag hebr_tag = FT_MAKE_TAG ('h', 'e', 'b', 'r');
guint script_index;
PangoOTInfo *info = pango_ot_info_get (face);
if (!ruleset_quark)
ruleset_quark = g_quark_from_string ("pango-hebrew-ruleset");
if (!info)
return NULL;
ruleset = g_object_get_qdata (G_OBJECT (info), ruleset_quark);
if (!ruleset)
{
if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GPOS,
hebr_tag, &script_index))
{
ruleset = pango_ot_ruleset_new (info);
/* Again, tags from the SBL font. */
maybe_add_gpos_feature (ruleset, info, script_index,
FT_MAKE_TAG ('k','e','r','n'), 0xFFFF);
maybe_add_gpos_feature (ruleset, info, script_index,
FT_MAKE_TAG ('m','a','r','k'), 0xFFFF);
}
else
/* Return NULL to trigger use of heuristics if there is no
* GPOS table in the font.
*/
return NULL;
if (pango_ot_info_find_script (info, PANGO_OT_TABLE_GSUB,
hebr_tag, &script_index))
{
/* Add the features that we want */
maybe_add_gsub_feature (ruleset, info, script_index,
FT_MAKE_TAG ('c','c','m','p'), 0xFFFF);
maybe_add_gsub_feature (ruleset, info, script_index,
FT_MAKE_TAG ('r','l','i','g'), 0xFFFF);
}
g_object_set_qdata_full (G_OBJECT (info), ruleset_quark, ruleset,
(GDestroyNotify)g_object_unref);
}
return ruleset;
}
static void
fallback_shape (PangoEngineShape *engine,
PangoFont *font,
const char *text,
gint length,
const PangoAnalysis *analysis,
PangoGlyphString *glyphs)
{
const char *p;
const char *log_cluster;
gunichar cluster[MAX_CLUSTER_CHRS];
gint cluster_size;
gint glyph_num[MAX_CLUSTER_CHRS];
gint glyph_width[MAX_CLUSTER_CHRS], x_offset[MAX_CLUSTER_CHRS], y_offset[MAX_CLUSTER_CHRS];
PangoRectangle ink_rects[MAX_CLUSTER_CHRS];
PangoGlyph glyph[MAX_CLUSTER_CHRS];
pango_glyph_string_set_size (glyphs, 0);
p = text;
while (p < text + length)
{
log_cluster = p;
p = hebrew_shaper_get_next_cluster (p, text + length - p,
/* output */
cluster, &cluster_size);
get_cluster_glyphs(font,
cluster,
cluster_size,
analysis->level % 2,
/* output */
glyph_num,
glyph,
glyph_width,
ink_rects);
/* Kern the glyphs! */
hebrew_shaper_get_cluster_kerning(cluster,
cluster_size,
/* Input and output */
ink_rects,
glyph_width,
/* output */
x_offset,
y_offset);
add_cluster(font,
glyphs,
cluster_size,
log_cluster - text,
glyph_num,
glyph,
glyph_width,
x_offset,
y_offset);
}
if (analysis->level % 2)
hebrew_shaper_bidi_reorder(glyphs);
}
static void
hebrew_engine_shape (PangoEngineShape *engine,
PangoFont *font,
const char *text,
gint length,
const PangoAnalysis *analysis,
PangoGlyphString *glyphs)
{
PangoFcFont *fc_font;
FT_Face face;
PangoOTRuleset *ruleset;
PangoOTBuffer *buffer;
gint unknown_property = 0;
glong n_chars;
const char *p;
int cluster = 0;
int i;
g_return_if_fail (font != NULL);
g_return_if_fail (text != NULL);
g_return_if_fail (length >= 0);
g_return_if_fail (analysis != NULL);
fc_font = PANGO_FC_FONT (font);
face = pango_fc_font_lock_face (fc_font);
if (!face)
return;
ruleset = get_ruleset (face);
if (!ruleset)
{
fallback_shape (engine, font, text, length, analysis, glyphs);
goto out;
}
buffer = pango_ot_buffer_new (fc_font);
pango_ot_buffer_set_rtl (buffer, analysis->level % 2 != 0);
n_chars = g_utf8_strlen (text, length);
p = text;
for (i=0; i < n_chars; i++)
{
gunichar wc;
gunichar mirrored_ch;
PangoGlyph index;
char buf[6];
wc = g_utf8_get_char (p);
if (analysis->level % 2)
if (pango_get_mirror_char (wc, &mirrored_ch))
{
wc = mirrored_ch;
g_unichar_to_utf8 (wc, buf);
}
if (pango_is_zero_width (wc)) /* Zero-width characters */
{
pango_ot_buffer_add_glyph (buffer, PANGO_GLYPH_EMPTY, unknown_property, p - text);
}
else
{
index = pango_fc_font_get_glyph (fc_font, wc);
if (!index)
{
pango_ot_buffer_add_glyph (buffer, PANGO_GET_UNKNOWN_GLYPH ( wc),
unknown_property, p - text);
}
else
{
cluster = p - text;
pango_ot_buffer_add_glyph (buffer, index,
unknown_property, cluster);
}
}
p = g_utf8_next_char (p);
}
pango_ot_ruleset_substitute (ruleset, buffer);
pango_ot_ruleset_position (ruleset, buffer);
pango_ot_buffer_output (buffer, glyphs);
pango_ot_buffer_destroy (buffer);
out:
pango_fc_font_unlock_face (fc_font);
}
static void
hebrew_engine_fc_class_init (PangoEngineShapeClass *class)
{
class->script_shape = hebrew_engine_shape;
}
PANGO_ENGINE_SHAPE_DEFINE_TYPE (HebrewEngineFc, hebrew_engine_fc,
hebrew_engine_fc_class_init, NULL)
void
PANGO_MODULE_ENTRY(init) (GTypeModule *module)
{
hebrew_engine_fc_register_type (module);
}
void
PANGO_MODULE_ENTRY(exit) (void)
{
}
void
PANGO_MODULE_ENTRY(list) (PangoEngineInfo **engines,
int *n_engines)
{
*engines = script_engines;
*n_engines = G_N_ELEMENTS (script_engines);
}
PangoEngine *
PANGO_MODULE_ENTRY(create) (const char *id)
{
if (!strcmp (id, SCRIPT_ENGINE_NAME))
return g_object_new (hebrew_engine_fc_type, NULL);
else
return NULL;
}
|