hb-coretext.cc revision ac2085d4b391b0a72473ecac3dd6c22efe66833f 
1/*
2 * Copyright © 2012  Mozilla Foundation.
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 * Mozilla Author(s): Jonathan Kew
25 */
26
27#include "hb-private.hh"
28
29#define GlyphID GlyphID_mac
30#include <ApplicationServices/ApplicationServices.h>
31#undef GlyphID
32
33#include "hb-coretext.h"
34
35#include "hb-ot-name-table.hh"
36#include "hb-ot-tag.h"
37
38#include "hb-font-private.hh"
39#include "hb-buffer-private.hh"
40
41
42#ifndef HB_DEBUG_CORETEXT
43#define HB_DEBUG_CORETEXT (HB_DEBUG+0)
44#endif
45
46
47static hb_user_data_key_t hb_coretext_data_key;
48
49static struct hb_coretext_face_data_t {
50  CGFontRef  cg_font;
51} _hb_coretext_face_data_nil = {0};
52
53static void
54_hb_coretext_face_data_destroy (hb_coretext_face_data_t *data)
55{
56  if (data->cg_font)
57    CFRelease (data->cg_font);
58  free (data);
59}
60
61static void
62release_data (void *info, const void *data, size_t size)
63{
64  assert (hb_blob_get_length ((hb_blob_t *) info) == size &&
65          hb_blob_get_data ((hb_blob_t *) info, NULL) == data);
66
67  hb_blob_destroy ((hb_blob_t *) info);
68}
69
70static hb_coretext_face_data_t *
71_hb_coretext_face_get_data (hb_face_t *face)
72{
73  hb_coretext_face_data_t *data = (hb_coretext_face_data_t *) hb_face_get_user_data (face, &hb_coretext_data_key);
74  if (likely (data)) return data;
75
76  data = (hb_coretext_face_data_t *) calloc (1, sizeof (hb_coretext_face_data_t));
77  if (unlikely (!data))
78    return &_hb_coretext_face_data_nil;
79
80
81  hb_blob_t *blob = hb_face_reference_blob (face);
82  unsigned int blob_length;
83  const char *blob_data = hb_blob_get_data (blob, &blob_length);
84  if (unlikely (!blob_length))
85    DEBUG_MSG (CORETEXT, face, "Face has empty blob");
86
87  CGDataProviderRef provider = CGDataProviderCreateWithData (blob, blob_data, blob_length, &release_data);
88  data->cg_font = CGFontCreateWithDataProvider (provider);
89  CGDataProviderRelease (provider);
90
91  if (unlikely (!data->cg_font))
92    DEBUG_MSG (CORETEXT, face, "Face CGFontCreateWithDataProvider() failed");
93
94
95  if (unlikely (!hb_face_set_user_data (face, &hb_coretext_data_key, data,
96                                        (hb_destroy_func_t) _hb_coretext_face_data_destroy,
97                                        false)))
98  {
99    _hb_coretext_face_data_destroy (data);
100    data = (hb_coretext_face_data_t *) hb_face_get_user_data (face, &hb_coretext_data_key);
101    if (data)
102      return data;
103    else
104      return &_hb_coretext_face_data_nil;
105  }
106
107  return data;
108}
109
110
111static struct hb_coretext_font_data_t {
112  CTFontRef ct_font;
113} _hb_coretext_font_data_nil = {0};
114
115static void
116_hb_coretext_font_data_destroy (hb_coretext_font_data_t *data)
117{
118  if (data->ct_font)
119    CFRelease (data->ct_font);
120  free (data);
121}
122
123static hb_coretext_font_data_t *
124_hb_coretext_font_get_data (hb_font_t *font)
125{
126  hb_coretext_font_data_t *data = (hb_coretext_font_data_t *) hb_font_get_user_data (font, &hb_coretext_data_key);
127  if (likely (data)) return data;
128
129  data = (hb_coretext_font_data_t *) calloc (1, sizeof (hb_coretext_font_data_t));
130  if (unlikely (!data))
131    return &_hb_coretext_font_data_nil;
132
133  hb_coretext_face_data_t *face_data = _hb_coretext_face_get_data (font->face);
134
135  data->ct_font = CTFontCreateWithGraphicsFont (face_data->cg_font, font->y_scale, NULL, NULL);
136  if (unlikely (!data->ct_font))
137    DEBUG_MSG (CORETEXT, font, "Font CTFontCreateWithGraphicsFont() failed");
138
139  if (unlikely (!hb_font_set_user_data (font, &hb_coretext_data_key, data,
140                                        (hb_destroy_func_t) _hb_coretext_font_data_destroy,
141                                        false)))
142  {
143    _hb_coretext_font_data_destroy (data);
144    data = (hb_coretext_font_data_t *) hb_font_get_user_data (font, &hb_coretext_data_key);
145    if (data)
146      return data;
147    else
148      return &_hb_coretext_font_data_nil;
149  }
150
151  return data;
152}
153
154CTFontRef
155hb_coretext_font_get_ct_font (hb_font_t *font)
156{
157  hb_coretext_font_data_t *font_data = _hb_coretext_font_get_data (font);
158  if (unlikely (!font_data))
159    return 0;
160  return font_data->ct_font;
161}
162
163
164hb_bool_t
165_hb_coretext_shape (hb_font_t          *font,
166                    hb_buffer_t        *buffer,
167                    const hb_feature_t *features,
168                    unsigned int        num_features)
169{
170  buffer->guess_properties ();
171
172#define FAIL(...) \
173  HB_STMT_START { \
174    DEBUG_MSG (CORETEXT, NULL, __VA_ARGS__); \
175    return false; \
176  } HB_STMT_END;
177
178  hb_coretext_face_data_t *face_data = _hb_coretext_face_get_data (font->face);
179  if (unlikely (!face_data->cg_font))
180    FAIL ("Couldn't get face data");
181
182  hb_coretext_font_data_t *font_data = _hb_coretext_font_get_data (font);
183  if (unlikely (!font_data->ct_font))
184    FAIL ("Couldn't get font font");
185
186  if (unlikely (!buffer->len))
187    return true;
188
189  unsigned int scratch_size;
190  char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
191
192#define utf16_index() var1.u32
193
194  UniChar *pchars = (UniChar *) scratch;
195  unsigned int chars_len = 0;
196  for (unsigned int i = 0; i < buffer->len; i++) {
197    hb_codepoint_t c = buffer->info[i].codepoint;
198    buffer->info[i].utf16_index() = chars_len;
199    if (likely (c < 0x10000))
200      pchars[chars_len++] = c;
201    else if (unlikely (c >= 0x110000))
202      pchars[chars_len++] = 0xFFFD;
203    else {
204      pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
205      pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
206    }
207  }
208
209#undef utf16_index
210
211  CFStringRef string_ref = CFStringCreateWithCharactersNoCopy (kCFAllocatorDefault,
212                                                               pchars, chars_len,
213                                                               kCFAllocatorNull);
214
215  CFDictionaryRef attrs = CFDictionaryCreate (kCFAllocatorDefault,
216                                              (const void**) &kCTFontAttributeName,
217                                              (const void**) &font_data->ct_font,
218                                              1, // count of attributes
219                                              &kCFTypeDictionaryKeyCallBacks,
220                                              &kCFTypeDictionaryValueCallBacks);
221
222  // TODO: support features
223
224  // Now we can create an attributed string
225  CFAttributedStringRef attr_string = CFAttributedStringCreate (kCFAllocatorDefault, string_ref, attrs);
226  CFRelease (string_ref);
227  CFRelease (attrs);
228
229  // Create the CoreText line from our string, then we're done with it
230  CTLineRef line = CTLineCreateWithAttributedString (attr_string);
231  CFRelease (attr_string);
232
233  // and finally retrieve the glyph data and store into the gfxTextRun
234  CFArrayRef glyph_runs = CTLineGetGlyphRuns (line);
235  unsigned int num_runs = CFArrayGetCount (glyph_runs);
236
237  // Iterate through the glyph runs.
238  bool success = true;
239  buffer->len = 0;
240
241  const CFRange range_all = CFRangeMake (0, 0);
242
243  for (unsigned int i = 0; i < num_runs; i++) {
244    CTRunRef run = (CTRunRef) CFArrayGetValueAtIndex (glyph_runs, i);
245
246    unsigned int num_glyphs = CTRunGetGlyphCount (run);
247    if (num_glyphs == 0)
248      continue;
249
250    buffer->ensure (buffer->len + num_glyphs);
251
252    // retrieve the laid-out glyph data from the CTRun
253
254    // Testing indicates that CTRunGetGlyphsPtr (almost?) always succeeds,
255    // and so copying data to our own buffer with CTRunGetGlyphs will be
256    // extremely rare.
257
258    unsigned int scratch_size;
259    char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
260
261#define ALLOCATE_ARRAY(Type, name, len) \
262  Type *name = (Type *) scratch; \
263  scratch += (len) * sizeof ((name)[0]); \
264  scratch_size -= (len) * sizeof ((name)[0]);
265
266    const CGGlyph* glyphs = CTRunGetGlyphsPtr (run);
267    if (!glyphs) {
268      ALLOCATE_ARRAY (CGGlyph, glyph_buf, num_glyphs);
269      CTRunGetGlyphs (run, range_all, glyph_buf);
270      glyphs = glyph_buf;
271    }
272
273    const CGPoint* positions = CTRunGetPositionsPtr (run);
274    if (!positions) {
275      ALLOCATE_ARRAY (CGPoint, position_buf, num_glyphs);
276      CTRunGetPositions (run, range_all, position_buf);
277      positions = position_buf;
278    }
279
280    const CFIndex* string_indices = CTRunGetStringIndicesPtr (run);
281    if (!string_indices) {
282      ALLOCATE_ARRAY (CFIndex, index_buf, num_glyphs);
283      CTRunGetStringIndices (run, range_all, index_buf);
284      string_indices = index_buf;
285    }
286
287#undef ALLOCATE_ARRAY
288
289    double run_width = CTRunGetTypographicBounds (run, range_all, NULL, NULL, NULL);
290
291    for (unsigned int j = 0; j < num_glyphs; j++) {
292      double advance = (j + 1 < num_glyphs ? positions[j + 1].x : positions[0].x + run_width) - positions[j].x;
293
294      hb_glyph_info_t *info = &buffer->info[buffer->len];
295      hb_glyph_position_t *pos = &buffer->pos[buffer->len];
296
297      info->codepoint = glyphs[j];
298      info->cluster = string_indices[j];
299
300      // currently, we do all x-positioning by setting the advance, we never use x-offset
301      info->mask = advance;
302      info->var1.u32 = 0;
303      info->var2.u32 = positions[j].y;
304
305      buffer->len++;
306    }
307  }
308
309  buffer->clear_positions ();
310
311  unsigned int count = buffer->len;
312  for (unsigned int i = 0; i < count; ++i) {
313    hb_glyph_info_t *info = &buffer->info[i];
314    hb_glyph_position_t *pos = &buffer->pos[i];
315
316    /* TODO vertical */
317    pos->x_advance = info->mask;
318    pos->x_offset = info->var1.u32;
319    pos->y_offset = info->var2.u32;
320  }
321
322  // Fix up clusters so that we never return out-of-order indices;
323  // if core text has reordered glyphs, we'll merge them to the
324  // beginning of the reordered cluster.
325  // This does *not* mean we'll form the same clusters as Uniscribe
326  // or the native OT backend, only that the cluster indices will be
327  // non-decreasing in the output buffer.
328  if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) {
329    unsigned int prev_cluster = 0;
330    for (unsigned int i = 0; i < count; i++) {
331      unsigned int curr_cluster = buffer->info[i].cluster;
332      if (curr_cluster < prev_cluster) {
333        for (unsigned int j = i; j > 0; j--) {
334          if (buffer->info[j - 1].cluster > curr_cluster)
335            buffer->info[j - 1].cluster = curr_cluster;
336          else
337            break;
338        }
339      }
340      prev_cluster = curr_cluster;
341    }
342  } else {
343    // For RTL runs, we make them non-increasing instead.
344    unsigned int prev_cluster = (unsigned int)-1;
345    for (unsigned int i = 0; i < count; i++) {
346      unsigned int curr_cluster = buffer->info[i].cluster;
347      if (curr_cluster > prev_cluster) {
348        for (unsigned int j = i; j > 0; j--) {
349          if (buffer->info[j - 1].cluster < curr_cluster)
350            buffer->info[j - 1].cluster = curr_cluster;
351          else
352            break;
353        }
354      }
355      prev_cluster = curr_cluster;
356    }
357  }
358
359  return true;
360}
361