• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 #ifndef HB_OT_SHAPE_COMPLEX_INDIC_PRIVATE_HH
28 #define HB_OT_SHAPE_COMPLEX_INDIC_PRIVATE_HH
29 
30 #include "hb-private.hh"
31 
32 
33 #include "hb-ot-shape-complex-private.hh"
34 #include "hb-ot-shape-private.hh" /* XXX Remove */
35 
36 
37 #define INDIC_TABLE_ELEMENT_TYPE uint16_t
38 
39 /* Cateories used in the OpenType spec:
40  * https://www.microsoft.com/typography/otfntdev/devanot/shaping.aspx
41  */
42 /* Note: This enum is duplicated in the -machine.rl source file.
43  * Not sure how to avoid duplication. */
44 enum indic_category_t {
45   OT_X = 0,
46   OT_C = 1,
47   OT_V = 2,
48   OT_N = 3,
49   OT_H = 4,
50   OT_ZWNJ = 5,
51   OT_ZWJ = 6,
52   OT_M = 7,
53   OT_SM = 8,
54   OT_VD = 9,
55   OT_A = 10,
56   OT_PLACEHOLDER = 11,
57   OT_DOTTEDCIRCLE = 12,
58   OT_RS = 13, /* Register Shifter, used in Khmer OT spec. */
59   OT_Coeng = 14, /* Khmer-style Virama. */
60   OT_Repha = 15, /* Atomically-encoded logical or visual repha. */
61   OT_Ra = 16,
62   OT_CM = 17,  /* Consonant-Medial. */
63   OT_Symbol = 18 /* Avagraha, etc that take marks (SM,A,VD). */
64 };
65 
66 #define MEDIAL_FLAGS (FLAG (OT_CM))
67 
68 /* Note:
69  *
70  * We treat Vowels and placeholders as if they were consonants.  This is safe because Vowels
71  * cannot happen in a consonant syllable.  The plus side however is, we can call the
72  * consonant syllable logic from the vowel syllable function and get it all right! */
73 #define CONSONANT_FLAGS (FLAG (OT_C) | FLAG (OT_Ra) | MEDIAL_FLAGS | FLAG (OT_V) | FLAG (OT_PLACEHOLDER) | FLAG (OT_DOTTEDCIRCLE))
74 #define JOINER_FLAGS (FLAG (OT_ZWJ) | FLAG (OT_ZWNJ))
75 #define HALANT_OR_COENG_FLAGS (FLAG (OT_H) | FLAG (OT_Coeng))
76 
77 
78 /* Visual positions in a syllable from left to right. */
79 enum indic_position_t {
80   POS_START,
81 
82   POS_RA_TO_BECOME_REPH,
83   POS_PRE_M,
84   POS_PRE_C,
85 
86   POS_BASE_C,
87   POS_AFTER_MAIN,
88 
89   POS_ABOVE_C,
90 
91   POS_BEFORE_SUB,
92   POS_BELOW_C,
93   POS_AFTER_SUB,
94 
95   POS_BEFORE_POST,
96   POS_POST_C,
97   POS_AFTER_POST,
98 
99   POS_FINAL_C,
100   POS_SMVD,
101 
102   POS_END
103 };
104 
105 /* Categories used in IndicSyllabicCategory.txt from UCD. */
106 enum indic_syllabic_category_t {
107   INDIC_SYLLABIC_CATEGORY_OTHER				= OT_X,
108 
109   INDIC_SYLLABIC_CATEGORY_AVAGRAHA			= OT_Symbol,
110   INDIC_SYLLABIC_CATEGORY_BINDU				= OT_SM,
111   INDIC_SYLLABIC_CATEGORY_BRAHMI_JOINING_NUMBER		= OT_PLACEHOLDER, /* Don't care. */
112   INDIC_SYLLABIC_CATEGORY_CANTILLATION_MARK		= OT_A,
113   INDIC_SYLLABIC_CATEGORY_CONSONANT			= OT_C,
114   INDIC_SYLLABIC_CATEGORY_CONSONANT_DEAD		= OT_C,
115   INDIC_SYLLABIC_CATEGORY_CONSONANT_FINAL		= OT_CM,
116   INDIC_SYLLABIC_CATEGORY_CONSONANT_HEAD_LETTER		= OT_C,
117   INDIC_SYLLABIC_CATEGORY_CONSONANT_KILLER		= OT_M, /* U+17CD only. */
118   INDIC_SYLLABIC_CATEGORY_CONSONANT_MEDIAL		= OT_CM,
119   INDIC_SYLLABIC_CATEGORY_CONSONANT_PLACEHOLDER		= OT_PLACEHOLDER,
120   INDIC_SYLLABIC_CATEGORY_CONSONANT_PRECEDING_REPHA	= OT_Repha,
121   INDIC_SYLLABIC_CATEGORY_CONSONANT_PREFIXED		= OT_X, /* Don't care. */
122   INDIC_SYLLABIC_CATEGORY_CONSONANT_SUBJOINED		= OT_CM,
123   INDIC_SYLLABIC_CATEGORY_CONSONANT_SUCCEEDING_REPHA	= OT_N,
124   INDIC_SYLLABIC_CATEGORY_CONSONANT_WITH_STACKER	= OT_C,
125   INDIC_SYLLABIC_CATEGORY_GEMINATION_MARK		= OT_SM,
126   INDIC_SYLLABIC_CATEGORY_INVISIBLE_STACKER		= OT_Coeng,
127   INDIC_SYLLABIC_CATEGORY_JOINER			= OT_ZWJ,
128   INDIC_SYLLABIC_CATEGORY_MODIFYING_LETTER		= OT_X,
129   INDIC_SYLLABIC_CATEGORY_NON_JOINER			= OT_ZWNJ,
130   INDIC_SYLLABIC_CATEGORY_NUKTA				= OT_N,
131   INDIC_SYLLABIC_CATEGORY_NUMBER			= OT_PLACEHOLDER,
132   INDIC_SYLLABIC_CATEGORY_NUMBER_JOINER			= OT_PLACEHOLDER, /* Don't care. */
133   INDIC_SYLLABIC_CATEGORY_PURE_KILLER			= OT_M, /* Is like a vowel matra. */
134   INDIC_SYLLABIC_CATEGORY_REGISTER_SHIFTER		= OT_RS,
135   INDIC_SYLLABIC_CATEGORY_SYLLABLE_MODIFIER		= OT_M, /* Misc Khmer signs. */
136   INDIC_SYLLABIC_CATEGORY_TONE_LETTER			= OT_X,
137   INDIC_SYLLABIC_CATEGORY_TONE_MARK			= OT_N,
138   INDIC_SYLLABIC_CATEGORY_VIRAMA			= OT_H,
139   INDIC_SYLLABIC_CATEGORY_VISARGA			= OT_SM,
140   INDIC_SYLLABIC_CATEGORY_VOWEL				= OT_V,
141   INDIC_SYLLABIC_CATEGORY_VOWEL_DEPENDENT		= OT_M,
142   INDIC_SYLLABIC_CATEGORY_VOWEL_INDEPENDENT		= OT_V
143 };
144 
145 /* Categories used in IndicSMatraCategory.txt from UCD */
146 enum indic_matra_category_t {
147   INDIC_MATRA_CATEGORY_NOT_APPLICABLE			= POS_END,
148 
149   INDIC_MATRA_CATEGORY_LEFT				= POS_PRE_C,
150   INDIC_MATRA_CATEGORY_TOP				= POS_ABOVE_C,
151   INDIC_MATRA_CATEGORY_BOTTOM				= POS_BELOW_C,
152   INDIC_MATRA_CATEGORY_RIGHT				= POS_POST_C,
153 
154   /* These should resolve to the position of the last part of the split sequence. */
155   INDIC_MATRA_CATEGORY_BOTTOM_AND_RIGHT			= INDIC_MATRA_CATEGORY_RIGHT,
156   INDIC_MATRA_CATEGORY_LEFT_AND_RIGHT			= INDIC_MATRA_CATEGORY_RIGHT,
157   INDIC_MATRA_CATEGORY_TOP_AND_BOTTOM			= INDIC_MATRA_CATEGORY_BOTTOM,
158   INDIC_MATRA_CATEGORY_TOP_AND_BOTTOM_AND_RIGHT		= INDIC_MATRA_CATEGORY_RIGHT,
159   INDIC_MATRA_CATEGORY_TOP_AND_LEFT			= INDIC_MATRA_CATEGORY_TOP,
160   INDIC_MATRA_CATEGORY_TOP_AND_LEFT_AND_RIGHT		= INDIC_MATRA_CATEGORY_RIGHT,
161   INDIC_MATRA_CATEGORY_TOP_AND_RIGHT			= INDIC_MATRA_CATEGORY_RIGHT,
162 
163   INDIC_MATRA_CATEGORY_OVERSTRUCK			= POS_AFTER_MAIN,
164   INDIC_MATRA_CATEGORY_VISUAL_ORDER_LEFT		= POS_PRE_M
165 };
166 
167 #define INDIC_COMBINE_CATEGORIES(S,M) \
168   ( \
169     ASSERT_STATIC_EXPR_ZERO (S < 255 && M < 255) + \
170     ( S | \
171      ( \
172       ( \
173        S == INDIC_SYLLABIC_CATEGORY_CONSONANT_MEDIAL || \
174        S == INDIC_SYLLABIC_CATEGORY_GEMINATION_MARK || \
175        S == INDIC_SYLLABIC_CATEGORY_REGISTER_SHIFTER || \
176        S == INDIC_SYLLABIC_CATEGORY_CONSONANT_SUCCEEDING_REPHA || \
177        S == INDIC_SYLLABIC_CATEGORY_VIRAMA || \
178        S == INDIC_SYLLABIC_CATEGORY_VOWEL_DEPENDENT || \
179        false \
180        ? M : INDIC_MATRA_CATEGORY_NOT_APPLICABLE \
181       ) << 8 \
182      ) \
183     ) \
184    )
185 
186 HB_INTERNAL INDIC_TABLE_ELEMENT_TYPE
187 hb_indic_get_categories (hb_codepoint_t u);
188 
189 #endif /* HB_OT_SHAPE_COMPLEX_INDIC_PRIVATE_HH */
190