Line data Source code
1 : /*
2 : * Copyright © 2011,2012 Google, Inc.
3 : *
4 : * This is part of HarfBuzz, a text shaping library.
5 : *
6 : * Permission is hereby granted, without written agreement and without
7 : * license or royalty fees, to use, copy, modify, and distribute this
8 : * software and its documentation for any purpose, provided that the
9 : * above copyright notice and the following two paragraphs appear in
10 : * all copies of this software.
11 : *
12 : * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 : * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 : * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 : * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 : * DAMAGE.
17 : *
18 : * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 : * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 : * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 : * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 : * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 : *
24 : * Google Author(s): Behdad Esfahbod
25 : */
26 :
27 : #include "hb-ot-shape-fallback-private.hh"
28 : #include "hb-ot-layout-gsubgpos-private.hh"
29 :
30 : static unsigned int
31 0 : recategorize_combining_class (hb_codepoint_t u,
32 : unsigned int klass)
33 : {
34 0 : if (klass >= 200)
35 0 : return klass;
36 :
37 : /* Thai / Lao need some per-character work. */
38 0 : if ((u & ~0xFF) == 0x0E00u)
39 : {
40 0 : if (unlikely (klass == 0))
41 : {
42 0 : switch (u)
43 : {
44 : case 0x0E31u:
45 : case 0x0E34u:
46 : case 0x0E35u:
47 : case 0x0E36u:
48 : case 0x0E37u:
49 : case 0x0E47u:
50 : case 0x0E4Cu:
51 : case 0x0E4Du:
52 : case 0x0E4Eu:
53 0 : klass = HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT;
54 0 : break;
55 :
56 : case 0x0EB1u:
57 : case 0x0EB4u:
58 : case 0x0EB5u:
59 : case 0x0EB6u:
60 : case 0x0EB7u:
61 : case 0x0EBBu:
62 : case 0x0ECCu:
63 : case 0x0ECDu:
64 0 : klass = HB_UNICODE_COMBINING_CLASS_ABOVE;
65 0 : break;
66 :
67 : case 0x0EBCu:
68 0 : klass = HB_UNICODE_COMBINING_CLASS_BELOW;
69 0 : break;
70 : }
71 : } else {
72 : /* Thai virama is below-right */
73 0 : if (u == 0x0E3Au)
74 0 : klass = HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT;
75 : }
76 : }
77 :
78 0 : switch (klass)
79 : {
80 :
81 : /* Hebrew */
82 :
83 : case HB_MODIFIED_COMBINING_CLASS_CCC10: /* sheva */
84 : case HB_MODIFIED_COMBINING_CLASS_CCC11: /* hataf segol */
85 : case HB_MODIFIED_COMBINING_CLASS_CCC12: /* hataf patah */
86 : case HB_MODIFIED_COMBINING_CLASS_CCC13: /* hataf qamats */
87 : case HB_MODIFIED_COMBINING_CLASS_CCC14: /* hiriq */
88 : case HB_MODIFIED_COMBINING_CLASS_CCC15: /* tsere */
89 : case HB_MODIFIED_COMBINING_CLASS_CCC16: /* segol */
90 : case HB_MODIFIED_COMBINING_CLASS_CCC17: /* patah */
91 : case HB_MODIFIED_COMBINING_CLASS_CCC18: /* qamats */
92 : case HB_MODIFIED_COMBINING_CLASS_CCC20: /* qubuts */
93 : case HB_MODIFIED_COMBINING_CLASS_CCC22: /* meteg */
94 0 : return HB_UNICODE_COMBINING_CLASS_BELOW;
95 :
96 : case HB_MODIFIED_COMBINING_CLASS_CCC23: /* rafe */
97 0 : return HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE;
98 :
99 : case HB_MODIFIED_COMBINING_CLASS_CCC24: /* shin dot */
100 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT;
101 :
102 : case HB_MODIFIED_COMBINING_CLASS_CCC25: /* sin dot */
103 : case HB_MODIFIED_COMBINING_CLASS_CCC19: /* holam */
104 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT;
105 :
106 : case HB_MODIFIED_COMBINING_CLASS_CCC26: /* point varika */
107 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE;
108 :
109 : case HB_MODIFIED_COMBINING_CLASS_CCC21: /* dagesh */
110 0 : break;
111 :
112 :
113 : /* Arabic and Syriac */
114 :
115 : case HB_MODIFIED_COMBINING_CLASS_CCC27: /* fathatan */
116 : case HB_MODIFIED_COMBINING_CLASS_CCC28: /* dammatan */
117 : case HB_MODIFIED_COMBINING_CLASS_CCC30: /* fatha */
118 : case HB_MODIFIED_COMBINING_CLASS_CCC31: /* damma */
119 : case HB_MODIFIED_COMBINING_CLASS_CCC33: /* shadda */
120 : case HB_MODIFIED_COMBINING_CLASS_CCC34: /* sukun */
121 : case HB_MODIFIED_COMBINING_CLASS_CCC35: /* superscript alef */
122 : case HB_MODIFIED_COMBINING_CLASS_CCC36: /* superscript alaph */
123 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE;
124 :
125 : case HB_MODIFIED_COMBINING_CLASS_CCC29: /* kasratan */
126 : case HB_MODIFIED_COMBINING_CLASS_CCC32: /* kasra */
127 0 : return HB_UNICODE_COMBINING_CLASS_BELOW;
128 :
129 :
130 : /* Thai */
131 :
132 : case HB_MODIFIED_COMBINING_CLASS_CCC103: /* sara u / sara uu */
133 0 : return HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT;
134 :
135 : case HB_MODIFIED_COMBINING_CLASS_CCC107: /* mai */
136 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT;
137 :
138 :
139 : /* Lao */
140 :
141 : case HB_MODIFIED_COMBINING_CLASS_CCC118: /* sign u / sign uu */
142 0 : return HB_UNICODE_COMBINING_CLASS_BELOW;
143 :
144 : case HB_MODIFIED_COMBINING_CLASS_CCC122: /* mai */
145 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE;
146 :
147 :
148 : /* Tibetan */
149 :
150 : case HB_MODIFIED_COMBINING_CLASS_CCC129: /* sign aa */
151 0 : return HB_UNICODE_COMBINING_CLASS_BELOW;
152 :
153 : case HB_MODIFIED_COMBINING_CLASS_CCC130: /* sign i*/
154 0 : return HB_UNICODE_COMBINING_CLASS_ABOVE;
155 :
156 : case HB_MODIFIED_COMBINING_CLASS_CCC132: /* sign u */
157 0 : return HB_UNICODE_COMBINING_CLASS_BELOW;
158 :
159 : }
160 :
161 0 : return klass;
162 : }
163 :
164 : void
165 0 : _hb_ot_shape_fallback_position_recategorize_marks (const hb_ot_shape_plan_t *plan HB_UNUSED,
166 : hb_font_t *font HB_UNUSED,
167 : hb_buffer_t *buffer)
168 : {
169 0 : unsigned int count = buffer->len;
170 0 : hb_glyph_info_t *info = buffer->info;
171 0 : for (unsigned int i = 0; i < count; i++)
172 0 : if (_hb_glyph_info_get_general_category (&info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) {
173 0 : unsigned int combining_class = _hb_glyph_info_get_modified_combining_class (&info[i]);
174 0 : combining_class = recategorize_combining_class (info[i].codepoint, combining_class);
175 0 : _hb_glyph_info_set_modified_combining_class (&info[i], combining_class);
176 : }
177 0 : }
178 :
179 :
180 : static void
181 0 : zero_mark_advances (hb_buffer_t *buffer,
182 : unsigned int start,
183 : unsigned int end)
184 : {
185 0 : hb_glyph_info_t *info = buffer->info;
186 0 : for (unsigned int i = start; i < end; i++)
187 0 : if (_hb_glyph_info_get_general_category (&info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)
188 : {
189 0 : buffer->pos[i].x_advance = 0;
190 0 : buffer->pos[i].y_advance = 0;
191 : }
192 0 : }
193 :
194 : static inline void
195 0 : position_mark (const hb_ot_shape_plan_t *plan,
196 : hb_font_t *font,
197 : hb_buffer_t *buffer,
198 : hb_glyph_extents_t &base_extents,
199 : unsigned int i,
200 : unsigned int combining_class)
201 : {
202 : hb_glyph_extents_t mark_extents;
203 0 : if (!font->get_glyph_extents (buffer->info[i].codepoint,
204 : &mark_extents))
205 0 : return;
206 :
207 0 : hb_position_t y_gap = font->y_scale / 16;
208 :
209 0 : hb_glyph_position_t &pos = buffer->pos[i];
210 0 : pos.x_offset = pos.y_offset = 0;
211 :
212 :
213 : /* We dont position LEFT and RIGHT marks. */
214 :
215 : /* X positioning */
216 0 : switch (combining_class)
217 : {
218 : case HB_UNICODE_COMBINING_CLASS_DOUBLE_BELOW:
219 : case HB_UNICODE_COMBINING_CLASS_DOUBLE_ABOVE:
220 0 : if (buffer->props.direction == HB_DIRECTION_LTR) {
221 0 : pos.x_offset += base_extents.x_bearing - mark_extents.width / 2 - mark_extents.x_bearing;
222 0 : break;
223 0 : } else if (buffer->props.direction == HB_DIRECTION_RTL) {
224 0 : pos.x_offset += base_extents.x_bearing + base_extents.width - mark_extents.width / 2 - mark_extents.x_bearing;
225 0 : break;
226 : }
227 : HB_FALLTHROUGH;
228 :
229 : default:
230 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW:
231 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE:
232 : case HB_UNICODE_COMBINING_CLASS_BELOW:
233 : case HB_UNICODE_COMBINING_CLASS_ABOVE:
234 : /* Center align. */
235 0 : pos.x_offset += base_extents.x_bearing + (base_extents.width - mark_extents.width) / 2 - mark_extents.x_bearing;
236 0 : break;
237 :
238 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW_LEFT:
239 : case HB_UNICODE_COMBINING_CLASS_BELOW_LEFT:
240 : case HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT:
241 : /* Left align. */
242 0 : pos.x_offset += base_extents.x_bearing - mark_extents.x_bearing;
243 0 : break;
244 :
245 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE_RIGHT:
246 : case HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT:
247 : case HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT:
248 : /* Right align. */
249 0 : pos.x_offset += base_extents.x_bearing + base_extents.width - mark_extents.width - mark_extents.x_bearing;
250 0 : break;
251 : }
252 :
253 : /* Y positioning */
254 0 : switch (combining_class)
255 : {
256 : case HB_UNICODE_COMBINING_CLASS_DOUBLE_BELOW:
257 : case HB_UNICODE_COMBINING_CLASS_BELOW_LEFT:
258 : case HB_UNICODE_COMBINING_CLASS_BELOW:
259 : case HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT:
260 : /* Add gap, fall-through. */
261 0 : base_extents.height -= y_gap;
262 : HB_FALLTHROUGH;
263 :
264 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW_LEFT:
265 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW:
266 0 : pos.y_offset = base_extents.y_bearing + base_extents.height - mark_extents.y_bearing;
267 : /* Never shift up "below" marks. */
268 0 : if ((y_gap > 0) == (pos.y_offset > 0))
269 : {
270 0 : base_extents.height -= pos.y_offset;
271 0 : pos.y_offset = 0;
272 : }
273 0 : base_extents.height += mark_extents.height;
274 0 : break;
275 :
276 : case HB_UNICODE_COMBINING_CLASS_DOUBLE_ABOVE:
277 : case HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT:
278 : case HB_UNICODE_COMBINING_CLASS_ABOVE:
279 : case HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT:
280 : /* Add gap, fall-through. */
281 0 : base_extents.y_bearing += y_gap;
282 0 : base_extents.height -= y_gap;
283 : HB_FALLTHROUGH;
284 :
285 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE:
286 : case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE_RIGHT:
287 0 : pos.y_offset = base_extents.y_bearing - (mark_extents.y_bearing + mark_extents.height);
288 : /* Don't shift down "above" marks too much. */
289 0 : if ((y_gap > 0) != (pos.y_offset > 0))
290 : {
291 0 : unsigned int correction = -pos.y_offset / 2;
292 0 : base_extents.y_bearing += correction;
293 0 : base_extents.height -= correction;
294 0 : pos.y_offset += correction;
295 : }
296 0 : base_extents.y_bearing -= mark_extents.height;
297 0 : base_extents.height += mark_extents.height;
298 0 : break;
299 : }
300 : }
301 :
302 : static inline void
303 0 : position_around_base (const hb_ot_shape_plan_t *plan,
304 : hb_font_t *font,
305 : hb_buffer_t *buffer,
306 : unsigned int base,
307 : unsigned int end)
308 : {
309 0 : hb_direction_t horiz_dir = HB_DIRECTION_INVALID;
310 : hb_glyph_extents_t base_extents;
311 0 : if (!font->get_glyph_extents (buffer->info[base].codepoint,
312 : &base_extents))
313 : {
314 : /* If extents don't work, zero marks and go home. */
315 0 : zero_mark_advances (buffer, base + 1, end);
316 0 : return;
317 : }
318 0 : base_extents.x_bearing += buffer->pos[base].x_offset;
319 0 : base_extents.y_bearing += buffer->pos[base].y_offset;
320 :
321 0 : unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[base]);
322 0 : unsigned int num_lig_components = _hb_glyph_info_get_lig_num_comps (&buffer->info[base]);
323 :
324 0 : hb_position_t x_offset = 0, y_offset = 0;
325 0 : if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) {
326 0 : x_offset -= buffer->pos[base].x_advance;
327 0 : y_offset -= buffer->pos[base].y_advance;
328 : }
329 :
330 0 : hb_glyph_extents_t component_extents = base_extents;
331 0 : unsigned int last_lig_component = (unsigned int) -1;
332 0 : unsigned int last_combining_class = 255;
333 0 : hb_glyph_extents_t cluster_extents = base_extents; /* Initialization is just to shut gcc up. */
334 0 : hb_glyph_info_t *info = buffer->info;
335 0 : for (unsigned int i = base + 1; i < end; i++)
336 0 : if (_hb_glyph_info_get_modified_combining_class (&info[i]))
337 : {
338 0 : if (num_lig_components > 1) {
339 0 : unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&info[i]);
340 0 : unsigned int this_lig_component = _hb_glyph_info_get_lig_comp (&info[i]) - 1;
341 : /* Conditions for attaching to the last component. */
342 0 : if (!lig_id || lig_id != this_lig_id || this_lig_component >= num_lig_components)
343 0 : this_lig_component = num_lig_components - 1;
344 0 : if (last_lig_component != this_lig_component)
345 : {
346 0 : last_lig_component = this_lig_component;
347 0 : last_combining_class = 255;
348 0 : component_extents = base_extents;
349 0 : if (unlikely (horiz_dir == HB_DIRECTION_INVALID)) {
350 0 : if (HB_DIRECTION_IS_HORIZONTAL (plan->props.direction))
351 0 : horiz_dir = plan->props.direction;
352 : else
353 0 : horiz_dir = hb_script_get_horizontal_direction (plan->props.script);
354 : }
355 0 : if (horiz_dir == HB_DIRECTION_LTR)
356 0 : component_extents.x_bearing += (this_lig_component * component_extents.width) / num_lig_components;
357 : else
358 0 : component_extents.x_bearing += ((num_lig_components - 1 - this_lig_component) * component_extents.width) / num_lig_components;
359 0 : component_extents.width /= num_lig_components;
360 : }
361 : }
362 :
363 0 : unsigned int this_combining_class = _hb_glyph_info_get_modified_combining_class (&info[i]);
364 0 : if (last_combining_class != this_combining_class)
365 : {
366 0 : last_combining_class = this_combining_class;
367 0 : cluster_extents = component_extents;
368 : }
369 :
370 0 : position_mark (plan, font, buffer, cluster_extents, i, this_combining_class);
371 :
372 0 : buffer->pos[i].x_advance = 0;
373 0 : buffer->pos[i].y_advance = 0;
374 0 : buffer->pos[i].x_offset += x_offset;
375 0 : buffer->pos[i].y_offset += y_offset;
376 :
377 : } else {
378 0 : if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) {
379 0 : x_offset -= buffer->pos[i].x_advance;
380 0 : y_offset -= buffer->pos[i].y_advance;
381 : } else {
382 0 : x_offset += buffer->pos[i].x_advance;
383 0 : y_offset += buffer->pos[i].y_advance;
384 : }
385 : }
386 : }
387 :
388 : static inline void
389 0 : position_cluster (const hb_ot_shape_plan_t *plan,
390 : hb_font_t *font,
391 : hb_buffer_t *buffer,
392 : unsigned int start,
393 : unsigned int end)
394 : {
395 0 : if (end - start < 2)
396 0 : return;
397 :
398 : /* Find the base glyph */
399 0 : hb_glyph_info_t *info = buffer->info;
400 0 : for (unsigned int i = start; i < end; i++)
401 0 : if (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])))
402 : {
403 : /* Find mark glyphs */
404 : unsigned int j;
405 0 : for (j = i + 1; j < end; j++)
406 0 : if (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[j])))
407 0 : break;
408 :
409 0 : position_around_base (plan, font, buffer, i, j);
410 :
411 0 : i = j - 1;
412 : }
413 : }
414 :
415 : void
416 0 : _hb_ot_shape_fallback_position (const hb_ot_shape_plan_t *plan,
417 : hb_font_t *font,
418 : hb_buffer_t *buffer)
419 : {
420 0 : _hb_buffer_assert_gsubgpos_vars (buffer);
421 :
422 0 : unsigned int start = 0;
423 0 : unsigned int count = buffer->len;
424 0 : hb_glyph_info_t *info = buffer->info;
425 0 : for (unsigned int i = 1; i < count; i++)
426 0 : if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])))) {
427 0 : position_cluster (plan, font, buffer, start, i);
428 0 : start = i;
429 : }
430 0 : position_cluster (plan, font, buffer, start, count);
431 0 : }
432 :
433 :
434 : /* Performs old-style TrueType kerning. */
435 : void
436 0 : _hb_ot_shape_fallback_kern (const hb_ot_shape_plan_t *plan,
437 : hb_font_t *font,
438 : hb_buffer_t *buffer)
439 : {
440 0 : if (!plan->has_kern) return;
441 :
442 0 : OT::hb_apply_context_t c (1, font, buffer);
443 0 : c.set_lookup_mask (plan->kern_mask);
444 0 : c.set_lookup_props (OT::LookupFlag::IgnoreMarks);
445 0 : OT::hb_apply_context_t::skipping_iterator_t &skippy_iter = c.iter_input;
446 0 : skippy_iter.init (&c);
447 :
448 0 : unsigned int count = buffer->len;
449 0 : hb_glyph_info_t *info = buffer->info;
450 0 : hb_glyph_position_t *pos = buffer->pos;
451 0 : for (unsigned int idx = 0; idx < count;)
452 : {
453 0 : skippy_iter.reset (idx, 1);
454 0 : if (!skippy_iter.next ())
455 : {
456 0 : idx++;
457 0 : continue;
458 : }
459 :
460 : hb_position_t x_kern, y_kern;
461 0 : font->get_glyph_kerning_for_direction (info[idx].codepoint,
462 0 : info[skippy_iter.idx].codepoint,
463 : buffer->props.direction,
464 0 : &x_kern, &y_kern);
465 :
466 0 : if (x_kern)
467 : {
468 0 : hb_position_t kern1 = x_kern >> 1;
469 0 : hb_position_t kern2 = x_kern - kern1;
470 0 : pos[idx].x_advance += kern1;
471 0 : pos[skippy_iter.idx].x_advance += kern2;
472 0 : pos[skippy_iter.idx].x_offset += kern2;
473 : }
474 :
475 0 : if (y_kern)
476 : {
477 0 : hb_position_t kern1 = y_kern >> 1;
478 0 : hb_position_t kern2 = y_kern - kern1;
479 0 : pos[idx].y_advance += kern1;
480 0 : pos[skippy_iter.idx].y_advance += kern2;
481 0 : pos[skippy_iter.idx].y_offset += kern2;
482 : }
483 :
484 0 : idx = skippy_iter.idx;
485 : }
486 : }
487 :
488 :
489 : /* Adjusts width of various spaces. */
490 : void
491 0 : _hb_ot_shape_fallback_spaces (const hb_ot_shape_plan_t *plan,
492 : hb_font_t *font,
493 : hb_buffer_t *buffer)
494 : {
495 0 : if (!HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction))
496 0 : return;
497 :
498 0 : hb_glyph_info_t *info = buffer->info;
499 0 : hb_glyph_position_t *pos = buffer->pos;
500 0 : unsigned int count = buffer->len;
501 0 : for (unsigned int i = 0; i < count; i++)
502 0 : if (_hb_glyph_info_is_unicode_space (&info[i]) && !_hb_glyph_info_ligated (&info[i]))
503 : {
504 0 : hb_unicode_funcs_t::space_t space_type = _hb_glyph_info_get_unicode_space_fallback_type (&info[i]);
505 : hb_codepoint_t glyph;
506 : typedef hb_unicode_funcs_t t;
507 0 : switch (space_type)
508 : {
509 : case t::NOT_SPACE: /* Shouldn't happen. */
510 : case t::SPACE:
511 0 : break;
512 :
513 : case t::SPACE_EM:
514 : case t::SPACE_EM_2:
515 : case t::SPACE_EM_3:
516 : case t::SPACE_EM_4:
517 : case t::SPACE_EM_5:
518 : case t::SPACE_EM_6:
519 : case t::SPACE_EM_16:
520 0 : pos[i].x_advance = (font->x_scale + ((int) space_type)/2) / (int) space_type;
521 0 : break;
522 :
523 : case t::SPACE_4_EM_18:
524 0 : pos[i].x_advance = font->x_scale * 4 / 18;
525 0 : break;
526 :
527 : case t::SPACE_FIGURE:
528 0 : for (char u = '0'; u <= '9'; u++)
529 0 : if (font->get_nominal_glyph (u, &glyph))
530 : {
531 0 : pos[i].x_advance = font->get_glyph_h_advance (glyph);
532 0 : break;
533 : }
534 0 : break;
535 :
536 : case t::SPACE_PUNCTUATION:
537 0 : if (font->get_nominal_glyph ('.', &glyph))
538 0 : pos[i].x_advance = font->get_glyph_h_advance (glyph);
539 0 : else if (font->get_nominal_glyph (',', &glyph))
540 0 : pos[i].x_advance = font->get_glyph_h_advance (glyph);
541 0 : break;
542 :
543 : case t::SPACE_NARROW:
544 : /* Half-space?
545 : * Unicode doc http://www.unicode.org/charts/PDF/U2000.pdf says ~1/4 or 1/5 of EM.
546 : * However, in my testing, many fonts have their regular space being about that
547 : * size. To me, a percentage of the space width makes more sense. Half is as
548 : * good as any. */
549 0 : pos[i].x_advance /= 2;
550 0 : break;
551 : }
552 : }
553 : }
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