third_party/harfbuzz-ng/src/hb-old.cc

   1 /*
   2  * Copyright © 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 #define HB_SHAPER old
  28 #define hb_old_shaper_face_data_t HB_FaceRec_
  29 #define hb_old_shaper_font_data_t HB_Font_
  30 #include "hb-shaper-impl-private.hh"
  31
  32 #include <harfbuzz.h>
  33
  34
  35 #ifndef HB_DEBUG_OLD
  36 #define HB_DEBUG_OLD (HB_DEBUG+0)
  37 #endif
  38
  39
  40 static HB_Script
  41 hb_old_script_from_script (hb_script_t script)
  42 {
  43   switch ((hb_tag_t) script)
  44   {
  45     default:
  46     case HB_SCRIPT_COMMON:              return HB_Script_Common;
  47     case HB_SCRIPT_GREEK:               return HB_Script_Greek;
  48     case HB_SCRIPT_CYRILLIC:            return HB_Script_Cyrillic;
  49     case HB_SCRIPT_ARMENIAN:            return HB_Script_Armenian;
  50     case HB_SCRIPT_HEBREW:              return HB_Script_Hebrew;
  51     case HB_SCRIPT_ARABIC:              return HB_Script_Arabic;
  52     case HB_SCRIPT_SYRIAC:              return HB_Script_Syriac;
  53     case HB_SCRIPT_THAANA:              return HB_Script_Thaana;
  54     case HB_SCRIPT_DEVANAGARI:          return HB_Script_Devanagari;
  55     case HB_SCRIPT_BENGALI:             return HB_Script_Bengali;
  56     case HB_SCRIPT_GURMUKHI:            return HB_Script_Gurmukhi;
  57     case HB_SCRIPT_GUJARATI:            return HB_Script_Gujarati;
  58     case HB_SCRIPT_ORIYA:               return HB_Script_Oriya;
  59     case HB_SCRIPT_TAMIL:               return HB_Script_Tamil;
  60     case HB_SCRIPT_TELUGU:              return HB_Script_Telugu;
  61     case HB_SCRIPT_KANNADA:             return HB_Script_Kannada;
  62     case HB_SCRIPT_MALAYALAM:           return HB_Script_Malayalam;
  63     case HB_SCRIPT_SINHALA:             return HB_Script_Sinhala;
  64     case HB_SCRIPT_THAI:                return HB_Script_Thai;
  65     case HB_SCRIPT_LAO:                 return HB_Script_Lao;
  66     case HB_SCRIPT_TIBETAN:             return HB_Script_Tibetan;
  67     case HB_SCRIPT_MYANMAR:             return HB_Script_Myanmar;
  68     case HB_SCRIPT_GEORGIAN:            return HB_Script_Georgian;
  69     case HB_SCRIPT_HANGUL:              return HB_Script_Hangul;
  70     case HB_SCRIPT_OGHAM:               return HB_Script_Ogham;
  71     case HB_SCRIPT_RUNIC:               return HB_Script_Runic;
  72     case HB_SCRIPT_KHMER:               return HB_Script_Khmer;
  73     case HB_SCRIPT_NKO:                 return HB_Script_Nko;
  74     case HB_SCRIPT_INHERITED:           return HB_Script_Inherited;
  75   }
  76 }
  77
  78
  79 static HB_Bool
  80 hb_old_convertStringToGlyphIndices (HB_Font old_font,
  81                                     const HB_UChar16 *string,
  82                                     hb_uint32 length,
  83                                     HB_Glyph *glyphs,
  84                                     hb_uint32 *numGlyphs,
  85                                     HB_Bool rightToLeft)
  86 {
  87   hb_font_t *font = (hb_font_t *) old_font->userData;
  88
  89   for (unsigned int i = 0; i < length; i++)
  90   {
  91     hb_codepoint_t u;
  92
  93     /* XXX Handle UTF-16.  Ugh */
  94     u = string[i];
  95
  96     if (rightToLeft)
  97       u = hb_unicode_funcs_get_default ()->mirroring (u);
  98
  99     font->get_glyph (u, 0, &u); /* TODO Variation selectors */
 100
 101     glyphs[i] = u;
 102   }
 103   *numGlyphs = length; /* XXX */
 104
 105   return true;
 106 }
 107
 108 static void
 109 hb_old_getGlyphAdvances (HB_Font old_font,
 110                          const HB_Glyph *glyphs,
 111                          hb_uint32 numGlyphs,
 112                          HB_Fixed *advances,
 113                          int flags /*HB_ShaperFlag*/ HB_UNUSED)
 114 {
 115   hb_font_t *font = (hb_font_t *) old_font->userData;
 116
 117   for (unsigned int i = 0; i < numGlyphs; i++)
 118     advances[i] = font->get_glyph_h_advance (glyphs[i]);
 119 }
 120
 121 static HB_Bool
 122 hb_old_canRender (HB_Font old_font,
 123                   const HB_UChar16 *string,
 124                   hb_uint32 length)
 125 {
 126   return true; /* TODO */
 127 }
 128
 129 static HB_Error
 130 hb_old_getPointInOutline (HB_Font old_font,
 131                           HB_Glyph glyph,
 132                           int flags /*HB_ShaperFlag*/,
 133                           hb_uint32 point,
 134                           HB_Fixed *xpos,
 135                           HB_Fixed *ypos,
 136                           hb_uint32 *nPoints)
 137 {
 138   return HB_Err_Ok; /* TODO */
 139 }
 140
 141 static void
 142 hb_old_getGlyphMetrics (HB_Font old_font,
 143                         HB_Glyph glyph,
 144                         HB_GlyphMetrics *metrics)
 145 {
 146   hb_font_t *font = (hb_font_t *) old_font->userData;
 147
 148   hb_glyph_extents_t extents;
 149
 150   font->get_glyph_extents (glyph, &extents);
 151
 152   metrics->x       = extents.x_bearing;
 153   metrics->y       = extents.y_bearing;
 154   metrics->width   = extents.width;
 155   metrics->height  = extents.height;
 156   metrics->xOffset = font->get_glyph_h_advance (glyph);
 157   metrics->yOffset = 0;
 158 }
 159
 160 static HB_Fixed
 161 hb_old_getFontMetric (HB_Font old_font,
 162                       HB_FontMetric metric)
 163 {
 164   hb_font_t *font = (hb_font_t *) old_font->userData;
 165
 166   switch (metric)
 167   {
 168     case HB_FontAscent:
 169        return font->y_scale; /* XXX We don't have ascent data yet. */
 170
 171     default:
 172       return 0;
 173   }
 174 }
 175
 176 static const HB_FontClass hb_old_font_class = {
 177   hb_old_convertStringToGlyphIndices,
 178   hb_old_getGlyphAdvances,
 179   hb_old_canRender,
 180   hb_old_getPointInOutline,
 181   hb_old_getGlyphMetrics,
 182   hb_old_getFontMetric
 183 };
 184
 185
 186
 187 static HB_Error
 188 table_func (void *font, HB_Tag tag, HB_Byte *buffer, HB_UInt *length)
 189 {
 190   hb_face_t *face = (hb_face_t *) font;
 191   hb_blob_t *blob = face->reference_table ((hb_tag_t) tag);
 192   unsigned int capacity = *length;
 193   *length = hb_blob_get_length (blob);
 194   memcpy (buffer, hb_blob_get_data (blob, NULL), MIN (capacity, *length));
 195   hb_blob_destroy (blob);
 196  return HB_Err_Ok;
 197 }
 198
 199
 200 /*
 201  * shaper face data
 202  */
 203
 204 hb_old_shaper_face_data_t *
 205 _hb_old_shaper_face_data_create (hb_face_t *face)
 206 {
 207   return HB_NewFace (face, table_func);
 208 }
 209
 210 void
 211 _hb_old_shaper_face_data_destroy (hb_old_shaper_face_data_t *data)
 212 {
 213   HB_FreeFace (data);
 214 }
 215
 216
 217 /*
 218  * shaper font data
 219  */
 220
 221 hb_old_shaper_font_data_t *
 222 _hb_old_shaper_font_data_create (hb_font_t *font)
 223 {
 224   HB_FontRec *data = (HB_FontRec *) calloc (1, sizeof (HB_FontRec));
 225   if (unlikely (!data)) {
 226     DEBUG_MSG (OLD, font, "malloc()ing HB_Font failed");
 227     return NULL;
 228   }
 229
 230   data->klass = &hb_old_font_class;
 231   data->x_ppem = font->x_ppem;
 232   data->y_ppem = font->y_ppem;
 233   data->x_scale = font->x_scale; /* XXX */
 234   data->y_scale = font->y_scale; /* XXX */
 235   data->userData = font;
 236
 237   return data;
 238 }
 239
 240 void
 241 _hb_old_shaper_font_data_destroy (hb_old_shaper_font_data_t *data)
 242 {
 243   free (data);
 244 }
 245
 246
 247 /*
 248  * shaper shape_plan data
 249  */
 250
 251 struct hb_old_shaper_shape_plan_data_t {};
 252
 253 hb_old_shaper_shape_plan_data_t *
 254 _hb_old_shaper_shape_plan_data_create (hb_shape_plan_t    *shape_plan HB_UNUSED,
 255                                        const hb_feature_t *user_features HB_UNUSED,
 256                                        unsigned int        num_user_features HB_UNUSED)
 257 {
 258   return (hb_old_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
 259 }
 260
 261 void
 262 _hb_old_shaper_shape_plan_data_destroy (hb_old_shaper_shape_plan_data_t *data HB_UNUSED)
 263 {
 264 }
 265
 266
 267 /*
 268  * shaper
 269  */
 270
 271 hb_bool_t
 272 _hb_old_shape (hb_shape_plan_t    *shape_plan HB_UNUSED,
 273                hb_font_t          *font,
 274                hb_buffer_t        *buffer,
 275                const hb_feature_t *features,
 276                unsigned int        num_features)
 277 {
 278   hb_face_t *face = font->face;
 279   HB_Face old_face = HB_SHAPER_DATA_GET (face);
 280   HB_Font old_font = HB_SHAPER_DATA_GET (font);
 281
 282   bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
 283
 284 retry:
 285
 286   unsigned int scratch_size;
 287   char *scratch = (char *) buffer->get_scratch_buffer (&scratch_size);
 288
 289 #define utf16_index() var1.u32
 290   HB_UChar16 *pchars = (HB_UChar16 *) scratch;
 291   unsigned int chars_len = 0;
 292   for (unsigned int i = 0; i < buffer->len; i++) {
 293     hb_codepoint_t c = buffer->info[i].codepoint;
 294     buffer->info[i].utf16_index() = chars_len;
 295     if (likely (c < 0x10000))
 296       pchars[chars_len++] = c;
 297     else if (unlikely (c >= 0x110000))
 298       pchars[chars_len++] = 0xFFFD;
 299     else {
 300       pchars[chars_len++] = 0xD800 + ((c - 0x10000) >> 10);
 301       pchars[chars_len++] = 0xDC00 + ((c - 0x10000) & ((1 << 10) - 1));
 302     }
 303   }
 304
 305
 306 #define ALLOCATE_ARRAY(Type, name, len) \
 307   name = (Type *) scratch; \
 308   scratch += (len) * sizeof ((name)[0]); \
 309   scratch_size -= (len) * sizeof ((name)[0]);
 310
 311
 312   HB_ShaperItem item = {0};
 313
 314   ALLOCATE_ARRAY (const HB_UChar16, item.string, chars_len);
 315   ALLOCATE_ARRAY (unsigned short, item.log_clusters, chars_len + 2);
 316   item.stringLength = chars_len;
 317   item.item.pos = 0;
 318   item.item.length = item.stringLength;
 319   item.item.script = hb_old_script_from_script (buffer->props.script);
 320   item.item.bidiLevel = backward ? 1 : 0;
 321
 322   item.font = old_font;
 323   item.face = old_face;
 324   item.shaperFlags = 0;
 325
 326   item.glyphIndicesPresent = false;
 327
 328   /* TODO Alignment. */
 329   unsigned int num_glyphs = scratch_size / (sizeof (HB_Glyph) +
 330                                             sizeof (HB_GlyphAttributes) +
 331                                             sizeof (HB_Fixed) +
 332                                             sizeof (HB_FixedPoint) +
 333                                             sizeof (uint32_t));
 334
 335   item.num_glyphs = num_glyphs;
 336   ALLOCATE_ARRAY (HB_Glyph, item.glyphs, num_glyphs);
 337   ALLOCATE_ARRAY (HB_GlyphAttributes, item.attributes, num_glyphs);
 338   ALLOCATE_ARRAY (HB_Fixed, item.advances, num_glyphs);
 339   ALLOCATE_ARRAY (HB_FixedPoint, item.offsets, num_glyphs);
 340   /* Apparently in some cases the offsets array will not be fully assigned to.
 341    * Clear it. */
 342   memset (item.offsets, 0, num_glyphs * sizeof (item.offsets[0]));
 343   uint32_t *vis_clusters;
 344   ALLOCATE_ARRAY (uint32_t, vis_clusters, num_glyphs);
 345
 346 #undef ALLOCATE_ARRAY
 347
 348   if (!HB_ShapeItem (&item))
 349   {
 350     if (unlikely (item.num_glyphs > num_glyphs))
 351     {
 352       buffer->ensure (buffer->allocated * 2);
 353       if (buffer->in_error)
 354         return false;
 355       goto retry;
 356     }
 357     return false;
 358   }
 359   num_glyphs = item.num_glyphs;
 360
 361   /* Ok, we've got everything we need, now compose output buffer,
 362    * very, *very*, carefully! */
 363
 364   /* Calculate visual-clusters.  That's what we ship. */
 365   for (unsigned int i = 0; i < num_glyphs; i++)
 366     vis_clusters[i] = -1;
 367   for (unsigned int i = 0; i < buffer->len; i++) {
 368     uint32_t *p = &vis_clusters[item.log_clusters[buffer->info[i].utf16_index()]];
 369     *p = MIN (*p, buffer->info[i].cluster);
 370   }
 371   for (unsigned int i = 1; i < num_glyphs; i++)
 372     if (vis_clusters[i] == (uint32_t) -1)
 373       vis_clusters[i] = vis_clusters[i - 1];
 374
 375 #undef utf16_index
 376
 377   buffer->ensure (num_glyphs);
 378   if (buffer->in_error)
 379     return false;
 380
 381
 382   buffer->len = num_glyphs;
 383   hb_glyph_info_t *info = buffer->info;
 384   for (unsigned int i = 0; i < num_glyphs; i++)
 385   {
 386     info[i].codepoint = item.glyphs[i];
 387     info[i].cluster = vis_clusters[i];
 388
 389     info[i].mask = item.advances[i];
 390     info[i].var1.u32 = item.offsets[i].x;
 391     info[i].var2.u32 = item.offsets[i].y;
 392   }
 393
 394   buffer->clear_positions ();
 395
 396   for (unsigned int i = 0; i < num_glyphs; ++i) {
 397     hb_glyph_info_t *info = &buffer->info[i];
 398     hb_glyph_position_t *pos = &buffer->pos[i];
 399
 400     /* TODO vertical */
 401     pos->x_advance = info->mask;
 402     pos->x_offset = info->var1.u32;
 403     pos->y_offset = info->var2.u32;
 404   }
 405
 406   if (HB_DIRECTION_IS_BACKWARD (buffer->props.direction))
 407     buffer->reverse ();
 408
 409   return true;
 410 }