1 /*
2  * Copyright © 2010,2012  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-complex-private.hh"
28 
29 
30 static bool
compose_hebrew(const hb_ot_shape_normalize_context_t * c,hb_codepoint_t a,hb_codepoint_t b,hb_codepoint_t * ab)31 compose_hebrew (const hb_ot_shape_normalize_context_t *c,
32 		hb_codepoint_t  a,
33 		hb_codepoint_t  b,
34 		hb_codepoint_t *ab)
35 {
36   /* Hebrew presentation-form shaping.
37    * https://bugzilla.mozilla.org/show_bug.cgi?id=728866
38    * Hebrew presentation forms with dagesh, for characters U+05D0..05EA;
39    * Note that some letters do not have a dagesh presForm encoded.
40    */
41   static const hb_codepoint_t sDageshForms[0x05EAu - 0x05D0u + 1] = {
42     0xFB30u, /* ALEF */
43     0xFB31u, /* BET */
44     0xFB32u, /* GIMEL */
45     0xFB33u, /* DALET */
46     0xFB34u, /* HE */
47     0xFB35u, /* VAV */
48     0xFB36u, /* ZAYIN */
49     0x0000u, /* HET */
50     0xFB38u, /* TET */
51     0xFB39u, /* YOD */
52     0xFB3Au, /* FINAL KAF */
53     0xFB3Bu, /* KAF */
54     0xFB3Cu, /* LAMED */
55     0x0000u, /* FINAL MEM */
56     0xFB3Eu, /* MEM */
57     0x0000u, /* FINAL NUN */
58     0xFB40u, /* NUN */
59     0xFB41u, /* SAMEKH */
60     0x0000u, /* AYIN */
61     0xFB43u, /* FINAL PE */
62     0xFB44u, /* PE */
63     0x0000u, /* FINAL TSADI */
64     0xFB46u, /* TSADI */
65     0xFB47u, /* QOF */
66     0xFB48u, /* RESH */
67     0xFB49u, /* SHIN */
68     0xFB4Au /* TAV */
69   };
70 
71   bool found = (bool) c->unicode->compose (a, b, ab);
72 
73   if (!found && !c->plan->has_mark)
74   {
75       /* Special-case Hebrew presentation forms that are excluded from
76        * standard normalization, but wanted for old fonts. */
77       switch (b) {
78       case 0x05B4u: /* HIRIQ */
79 	  if (a == 0x05D9u) { /* YOD */
80 	      *ab = 0xFB1Du;
81 	      found = true;
82 	  }
83 	  break;
84       case 0x05B7u: /* patah */
85 	  if (a == 0x05F2u) { /* YIDDISH YOD YOD */
86 	      *ab = 0xFB1Fu;
87 	      found = true;
88 	  } else if (a == 0x05D0u) { /* ALEF */
89 	      *ab = 0xFB2Eu;
90 	      found = true;
91 	  }
92 	  break;
93       case 0x05B8u: /* QAMATS */
94 	  if (a == 0x05D0u) { /* ALEF */
95 	      *ab = 0xFB2Fu;
96 	      found = true;
97 	  }
98 	  break;
99       case 0x05B9u: /* HOLAM */
100 	  if (a == 0x05D5u) { /* VAV */
101 	      *ab = 0xFB4Bu;
102 	      found = true;
103 	  }
104 	  break;
105       case 0x05BCu: /* DAGESH */
106 	  if (a >= 0x05D0u && a <= 0x05EAu) {
107 	      *ab = sDageshForms[a - 0x05D0u];
108 	      found = (*ab != 0);
109 	  } else if (a == 0xFB2Au) { /* SHIN WITH SHIN DOT */
110 	      *ab = 0xFB2Cu;
111 	      found = true;
112 	  } else if (a == 0xFB2Bu) { /* SHIN WITH SIN DOT */
113 	      *ab = 0xFB2Du;
114 	      found = true;
115 	  }
116 	  break;
117       case 0x05BFu: /* RAFE */
118 	  switch (a) {
119 	  case 0x05D1u: /* BET */
120 	      *ab = 0xFB4Cu;
121 	      found = true;
122 	      break;
123 	  case 0x05DBu: /* KAF */
124 	      *ab = 0xFB4Du;
125 	      found = true;
126 	      break;
127 	  case 0x05E4u: /* PE */
128 	      *ab = 0xFB4Eu;
129 	      found = true;
130 	      break;
131 	  }
132 	  break;
133       case 0x05C1u: /* SHIN DOT */
134 	  if (a == 0x05E9u) { /* SHIN */
135 	      *ab = 0xFB2Au;
136 	      found = true;
137 	  } else if (a == 0xFB49u) { /* SHIN WITH DAGESH */
138 	      *ab = 0xFB2Cu;
139 	      found = true;
140 	  }
141 	  break;
142       case 0x05C2u: /* SIN DOT */
143 	  if (a == 0x05E9u) { /* SHIN */
144 	      *ab = 0xFB2Bu;
145 	      found = true;
146 	  } else if (a == 0xFB49u) { /* SHIN WITH DAGESH */
147 	      *ab = 0xFB2Du;
148 	      found = true;
149 	  }
150 	  break;
151       }
152   }
153 
154   return found;
155 }
156 
157 static bool
disable_otl_hebrew(const hb_ot_shape_plan_t * plan)158 disable_otl_hebrew (const hb_ot_shape_plan_t *plan)
159 {
160   /* For Hebrew shaper, use fallback if GPOS does not have 'hebr'
161    * script.  This matches Uniscribe better, and makes fonts like
162    * Arial that have GSUB/GPOS/GDEF but no data for Hebrew work.
163    * See:
164    * https://github.com/behdad/harfbuzz/issues/347#issuecomment-267838368
165    */
166   return plan->map.chosen_script[1] != HB_TAG ('h','e','b','r');
167 }
168 
169 
170 const hb_ot_complex_shaper_t _hb_ot_complex_shaper_hebrew =
171 {
172   "hebrew",
173   NULL, /* collect_features */
174   NULL, /* override_features */
175   NULL, /* data_create */
176   NULL, /* data_destroy */
177   NULL, /* preprocess_text */
178   NULL, /* postprocess_glyphs */
179   HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT,
180   NULL, /* decompose */
181   compose_hebrew,
182   NULL, /* setup_masks */
183   disable_otl_hebrew,
184   HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE,
185   true, /* fallback_position */
186 };
187