1/*
2 * Copyright © 2016 Igalia S.L.
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 * Igalia Author(s): Frédéric Wang
25 */
26
27#ifndef HB_OT_H_IN
28#error "Include <hb-ot.h> instead."
29#endif
30
31#ifndef HB_OT_MATH_H
32#define HB_OT_MATH_H
33
34#include "hb.h"
35
36HB_BEGIN_DECLS
37
38
39/*
40 * MATH
41 */
42
43#define HB_OT_TAG_MATH HB_TAG('M','A','T','H')
44
45/* Use with hb_buffer_set_script() for math shaping. */
46#define HB_OT_MATH_SCRIPT HB_TAG('m','a','t','h')
47
48/* Types */
49
50/**
51 * hb_ot_math_constant_t:
52 *
53 * The 'MATH' table constants specified at
54 * https://docs.microsoft.com/en-us/typography/opentype/spec/math
55 *
56 * Since: 1.3.3
57 */
58typedef enum {
59 HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN = 0,
60 HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN = 1,
61 HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT = 2,
62 HB_OT_MATH_CONSTANT_DISPLAY_OPERATOR_MIN_HEIGHT = 3,
63 HB_OT_MATH_CONSTANT_MATH_LEADING = 4,
64 HB_OT_MATH_CONSTANT_AXIS_HEIGHT = 5,
65 HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT = 6,
66 HB_OT_MATH_CONSTANT_FLATTENED_ACCENT_BASE_HEIGHT = 7,
67 HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN = 8,
68 HB_OT_MATH_CONSTANT_SUBSCRIPT_TOP_MAX = 9,
69 HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN = 10,
70 HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP = 11,
71 HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED = 12,
72 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MIN = 13,
73 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX = 14,
74 HB_OT_MATH_CONSTANT_SUB_SUPERSCRIPT_GAP_MIN = 15,
75 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MAX_WITH_SUBSCRIPT = 16,
76 HB_OT_MATH_CONSTANT_SPACE_AFTER_SCRIPT = 17,
77 HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN = 18,
78 HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN = 19,
79 HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN = 20,
80 HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN = 21,
81 HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP = 22,
82 HB_OT_MATH_CONSTANT_STACK_TOP_DISPLAY_STYLE_SHIFT_UP = 23,
83 HB_OT_MATH_CONSTANT_STACK_BOTTOM_SHIFT_DOWN = 24,
84 HB_OT_MATH_CONSTANT_STACK_BOTTOM_DISPLAY_STYLE_SHIFT_DOWN = 25,
85 HB_OT_MATH_CONSTANT_STACK_GAP_MIN = 26,
86 HB_OT_MATH_CONSTANT_STACK_DISPLAY_STYLE_GAP_MIN = 27,
87 HB_OT_MATH_CONSTANT_STRETCH_STACK_TOP_SHIFT_UP = 28,
88 HB_OT_MATH_CONSTANT_STRETCH_STACK_BOTTOM_SHIFT_DOWN = 29,
89 HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_ABOVE_MIN = 30,
90 HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_BELOW_MIN = 31,
91 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP = 32,
92 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP = 33,
93 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN = 34,
94 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN = 35,
95 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_GAP_MIN = 36,
96 HB_OT_MATH_CONSTANT_FRACTION_NUM_DISPLAY_STYLE_GAP_MIN = 37,
97 HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS = 38,
98 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_GAP_MIN = 39,
99 HB_OT_MATH_CONSTANT_FRACTION_DENOM_DISPLAY_STYLE_GAP_MIN = 40,
100 HB_OT_MATH_CONSTANT_SKEWED_FRACTION_HORIZONTAL_GAP = 41,
101 HB_OT_MATH_CONSTANT_SKEWED_FRACTION_VERTICAL_GAP = 42,
102 HB_OT_MATH_CONSTANT_OVERBAR_VERTICAL_GAP = 43,
103 HB_OT_MATH_CONSTANT_OVERBAR_RULE_THICKNESS = 44,
104 HB_OT_MATH_CONSTANT_OVERBAR_EXTRA_ASCENDER = 45,
105 HB_OT_MATH_CONSTANT_UNDERBAR_VERTICAL_GAP = 46,
106 HB_OT_MATH_CONSTANT_UNDERBAR_RULE_THICKNESS = 47,
107 HB_OT_MATH_CONSTANT_UNDERBAR_EXTRA_DESCENDER = 48,
108 HB_OT_MATH_CONSTANT_RADICAL_VERTICAL_GAP = 49,
109 HB_OT_MATH_CONSTANT_RADICAL_DISPLAY_STYLE_VERTICAL_GAP = 50,
110 HB_OT_MATH_CONSTANT_RADICAL_RULE_THICKNESS = 51,
111 HB_OT_MATH_CONSTANT_RADICAL_EXTRA_ASCENDER = 52,
112 HB_OT_MATH_CONSTANT_RADICAL_KERN_BEFORE_DEGREE = 53,
113 HB_OT_MATH_CONSTANT_RADICAL_KERN_AFTER_DEGREE = 54,
114 HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT = 55
115} hb_ot_math_constant_t;
116
117/**
118 * hb_ot_math_kern_t:
119 *
120 * The math kerning-table types defined for the four corners
121 * of a glyph.
122 *
123 * Since: 1.3.3
124 */
125typedef enum {
126 HB_OT_MATH_KERN_TOP_RIGHT = 0,
127 HB_OT_MATH_KERN_TOP_LEFT = 1,
128 HB_OT_MATH_KERN_BOTTOM_RIGHT = 2,
129 HB_OT_MATH_KERN_BOTTOM_LEFT = 3
130} hb_ot_math_kern_t;
131
132/**
133 * hb_ot_math_glyph_variant_t:
134 * @glyph: The glyph index of the variant
135 * @advance: The advance width of the variant
136 *
137 * Data type to hold math-variant information for a glyph.
138 *
139 * Since: 1.3.3
140 */
141typedef struct hb_ot_math_glyph_variant_t {
142 hb_codepoint_t glyph;
143 hb_position_t advance;
144} hb_ot_math_glyph_variant_t;
145
146/**
147 * hb_ot_math_glyph_part_flags_t:
148 *
149 * Flags for math glyph parts.
150 *
151 * Since: 1.3.3
152 */
153typedef enum { /*< flags >*/
154 HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER = 0x00000001u /* Extender glyph */
155} hb_ot_math_glyph_part_flags_t;
156
157/**
158 * hb_ot_math_glyph_part_t:
159 * @glyph: The glyph index of the variant part
160 * @start_connector_length: The length of the connector on the starting side of the variant part
161 * @end_connector_length: The length of the connector on the ending side of the variant part
162 * @full_advance: The total advance of the part
163 * @flags: #hb_ot_math_glyph_part_flags_t flags for the part
164 *
165 * Data type to hold information for a "part" component of a math-variant glyph.
166 * Large variants for stretchable math glyphs (such as parentheses) can be constructed
167 * on the fly from parts.
168 *
169 * Since: 1.3.3
170 */
171typedef struct hb_ot_math_glyph_part_t {
172 hb_codepoint_t glyph;
173 hb_position_t start_connector_length;
174 hb_position_t end_connector_length;
175 hb_position_t full_advance;
176 hb_ot_math_glyph_part_flags_t flags;
177} hb_ot_math_glyph_part_t;
178
179/* Methods */
180
181HB_EXTERN hb_bool_t
182hb_ot_math_has_data (hb_face_t *face);
183
184HB_EXTERN hb_position_t
185hb_ot_math_get_constant (hb_font_t *font,
186 hb_ot_math_constant_t constant);
187
188HB_EXTERN hb_position_t
189hb_ot_math_get_glyph_italics_correction (hb_font_t *font,
190 hb_codepoint_t glyph);
191
192HB_EXTERN hb_position_t
193hb_ot_math_get_glyph_top_accent_attachment (hb_font_t *font,
194 hb_codepoint_t glyph);
195
196HB_EXTERN hb_bool_t
197hb_ot_math_is_glyph_extended_shape (hb_face_t *face,
198 hb_codepoint_t glyph);
199
200HB_EXTERN hb_position_t
201hb_ot_math_get_glyph_kerning (hb_font_t *font,
202 hb_codepoint_t glyph,
203 hb_ot_math_kern_t kern,
204 hb_position_t correction_height);
205
206HB_EXTERN unsigned int
207hb_ot_math_get_glyph_variants (hb_font_t *font,
208 hb_codepoint_t glyph,
209 hb_direction_t direction,
210 unsigned int start_offset,
211 unsigned int *variants_count, /* IN/OUT */
212 hb_ot_math_glyph_variant_t *variants /* OUT */);
213
214HB_EXTERN hb_position_t
215hb_ot_math_get_min_connector_overlap (hb_font_t *font,
216 hb_direction_t direction);
217
218HB_EXTERN unsigned int
219hb_ot_math_get_glyph_assembly (hb_font_t *font,
220 hb_codepoint_t glyph,
221 hb_direction_t direction,
222 unsigned int start_offset,
223 unsigned int *parts_count, /* IN/OUT */
224 hb_ot_math_glyph_part_t *parts, /* OUT */
225 hb_position_t *italics_correction /* OUT */);
226
227
228HB_END_DECLS
229
230#endif /* HB_OT_MATH_H */
231

source code of include/harfbuzz/hb-ot-math.h