gfx/harfbuzz/src/hb-ot-shape-complex-syllabic.cc

   1 /*
   2  * Copyright © 2021  Behdad Esfahbod.
   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
  25 #include "hb.hh"
  26
  27 #ifndef HB_NO_OT_SHAPE
  28
  29 #include "hb-ot-shape-complex-syllabic.hh"
  30
  31
  32 void
  33 hb_syllabic_insert_dotted_circles (hb_font_t *font,
  34                                    hb_buffer_t *buffer,
  35                                    unsigned int broken_syllable_type,
  36                                    unsigned int dottedcircle_category,
  37                                    int repha_category,
  38                                    int dottedcircle_position)
  39 {
  40   if (unlikely (buffer->flags & HB_BUFFER_FLAG_DO_NOT_INSERT_DOTTED_CIRCLE))
  41     return;
  42
  43   /* Note: This loop is extra overhead, but should not be measurable.
  44    * TODO Use a buffer scratch flag to remove the loop. */
  45   bool has_broken_syllables = false;
  46   unsigned int count = buffer->len;
  47   hb_glyph_info_t *info = buffer->info;
  48   for (unsigned int i = 0; i < count; i++)
  49     if ((info[i].syllable() & 0x0F) == broken_syllable_type)
  50     {
  51       has_broken_syllables = true;
  52       break;
  53     }
  54   if (likely (!has_broken_syllables))
  55     return;
  56
  57
  58   hb_codepoint_t dottedcircle_glyph;
  59   if (!font->get_nominal_glyph (0x25CCu, &dottedcircle_glyph))
  60     return;
  61
  62   hb_glyph_info_t dottedcircle = {0};
  63   dottedcircle.codepoint = 0x25CCu;
  64   dottedcircle.complex_var_u8_category() = dottedcircle_category;
  65   if (dottedcircle_position != -1)
  66     dottedcircle.complex_var_u8_auxiliary() = dottedcircle_position;
  67   dottedcircle.codepoint = dottedcircle_glyph;
  68
  69   buffer->clear_output ();
  70
  71   buffer->idx = 0;
  72   unsigned int last_syllable = 0;
  73   while (buffer->idx < buffer->len && buffer->successful)
  74   {
  75     unsigned int syllable = buffer->cur().syllable();
  76     if (unlikely (last_syllable != syllable && (syllable & 0x0F) == broken_syllable_type))
  77     {
  78       last_syllable = syllable;
  79
  80       hb_glyph_info_t ginfo = dottedcircle;
  81       ginfo.cluster = buffer->cur().cluster;
  82       ginfo.mask = buffer->cur().mask;
  83       ginfo.syllable() = buffer->cur().syllable();
  84
  85       /* Insert dottedcircle after possible Repha. */
  86       if (repha_category != -1)
  87       {
  88         while (buffer->idx < buffer->len && buffer->successful &&
  89                last_syllable == buffer->cur().syllable() &&
  90                buffer->cur().complex_var_u8_category() == (unsigned) repha_category)
  91           (void) buffer->next_glyph ();
  92       }
  93
  94       (void) buffer->output_info (ginfo);
  95     }
  96     else
  97       (void) buffer->next_glyph ();
  98   }
  99   buffer->sync ();
 100 }
 101
 102
 103 #endif