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
hb_syllabic_insert_dotted_circles(hb_font_t * font,hb_buffer_t * buffer,unsigned int broken_syllable_type,unsigned int dottedcircle_category,int repha_category,int dottedcircle_position)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
104