hb-ot-math.h (13761B)
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 #if !defined(HB_OT_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR) 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 36 HB_BEGIN_DECLS 37 38 39 /* 40 * MATH 41 */ 42 43 /** 44 * HB_OT_TAG_MATH: 45 * 46 * OpenType [Mathematical Typesetting Table](https://docs.microsoft.com/en-us/typography/opentype/spec/math). 47 * 48 * Since: 1.3.3 49 */ 50 #define HB_OT_TAG_MATH HB_TAG('M','A','T','H') 51 52 /** 53 * HB_OT_TAG_MATH_SCRIPT: 54 * 55 * OpenType script tag, `math`, for features specific to math shaping. 56 * 57 * <note>#HB_OT_TAG_MATH_SCRIPT is not a valid #hb_script_t and should only be 58 * used with functions that accept raw OpenType script tags, such as 59 * #hb_ot_layout_collect_features. In other cases, #HB_SCRIPT_MATH should be 60 * used instead.</note> 61 * 62 * Since: 3.4.0 63 */ 64 #define HB_OT_TAG_MATH_SCRIPT HB_TAG('m','a','t','h') 65 66 /* Types */ 67 68 /** 69 * hb_ot_math_constant_t: 70 * @HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN: scriptPercentScaleDown 71 * @HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN: scriptScriptPercentScaleDown 72 * @HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT: delimitedSubFormulaMinHeight 73 * @HB_OT_MATH_CONSTANT_DISPLAY_OPERATOR_MIN_HEIGHT: displayOperatorMinHeight 74 * @HB_OT_MATH_CONSTANT_MATH_LEADING: mathLeading 75 * @HB_OT_MATH_CONSTANT_AXIS_HEIGHT: axisHeight 76 * @HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT: accentBaseHeight 77 * @HB_OT_MATH_CONSTANT_FLATTENED_ACCENT_BASE_HEIGHT: flattenedAccentBaseHeight 78 * @HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN: subscriptShiftDown 79 * @HB_OT_MATH_CONSTANT_SUBSCRIPT_TOP_MAX: subscriptTopMax 80 * @HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN: subscriptBaselineDropMin 81 * @HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP: superscriptShiftUp 82 * @HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED: superscriptShiftUpCramped 83 * @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MIN: superscriptBottomMin 84 * @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX: superscriptBaselineDropMax 85 * @HB_OT_MATH_CONSTANT_SUB_SUPERSCRIPT_GAP_MIN: subSuperscriptGapMin 86 * @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MAX_WITH_SUBSCRIPT: superscriptBottomMaxWithSubscript 87 * @HB_OT_MATH_CONSTANT_SPACE_AFTER_SCRIPT: spaceAfterScript 88 * @HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN: upperLimitGapMin 89 * @HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN: upperLimitBaselineRiseMin 90 * @HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN: lowerLimitGapMin 91 * @HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN: lowerLimitBaselineDropMin 92 * @HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP: stackTopShiftUp 93 * @HB_OT_MATH_CONSTANT_STACK_TOP_DISPLAY_STYLE_SHIFT_UP: stackTopDisplayStyleShiftUp 94 * @HB_OT_MATH_CONSTANT_STACK_BOTTOM_SHIFT_DOWN: stackBottomShiftDown 95 * @HB_OT_MATH_CONSTANT_STACK_BOTTOM_DISPLAY_STYLE_SHIFT_DOWN: stackBottomDisplayStyleShiftDown 96 * @HB_OT_MATH_CONSTANT_STACK_GAP_MIN: stackGapMin 97 * @HB_OT_MATH_CONSTANT_STACK_DISPLAY_STYLE_GAP_MIN: stackDisplayStyleGapMin 98 * @HB_OT_MATH_CONSTANT_STRETCH_STACK_TOP_SHIFT_UP: stretchStackTopShiftUp 99 * @HB_OT_MATH_CONSTANT_STRETCH_STACK_BOTTOM_SHIFT_DOWN: stretchStackBottomShiftDown 100 * @HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_ABOVE_MIN: stretchStackGapAboveMin 101 * @HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_BELOW_MIN: stretchStackGapBelowMin 102 * @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP: fractionNumeratorShiftUp 103 * @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP: fractionNumeratorDisplayStyleShiftUp 104 * @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN: fractionDenominatorShiftDown 105 * @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN: fractionDenominatorDisplayStyleShiftDown 106 * @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_GAP_MIN: fractionNumeratorGapMin 107 * @HB_OT_MATH_CONSTANT_FRACTION_NUM_DISPLAY_STYLE_GAP_MIN: fractionNumDisplayStyleGapMin 108 * @HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS: fractionRuleThickness 109 * @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_GAP_MIN: fractionDenominatorGapMin 110 * @HB_OT_MATH_CONSTANT_FRACTION_DENOM_DISPLAY_STYLE_GAP_MIN: fractionDenomDisplayStyleGapMin 111 * @HB_OT_MATH_CONSTANT_SKEWED_FRACTION_HORIZONTAL_GAP: skewedFractionHorizontalGap 112 * @HB_OT_MATH_CONSTANT_SKEWED_FRACTION_VERTICAL_GAP: skewedFractionVerticalGap 113 * @HB_OT_MATH_CONSTANT_OVERBAR_VERTICAL_GAP: overbarVerticalGap 114 * @HB_OT_MATH_CONSTANT_OVERBAR_RULE_THICKNESS: overbarRuleThickness 115 * @HB_OT_MATH_CONSTANT_OVERBAR_EXTRA_ASCENDER: overbarExtraAscender 116 * @HB_OT_MATH_CONSTANT_UNDERBAR_VERTICAL_GAP: underbarVerticalGap 117 * @HB_OT_MATH_CONSTANT_UNDERBAR_RULE_THICKNESS: underbarRuleThickness 118 * @HB_OT_MATH_CONSTANT_UNDERBAR_EXTRA_DESCENDER: underbarExtraDescender 119 * @HB_OT_MATH_CONSTANT_RADICAL_VERTICAL_GAP: radicalVerticalGap 120 * @HB_OT_MATH_CONSTANT_RADICAL_DISPLAY_STYLE_VERTICAL_GAP: radicalDisplayStyleVerticalGap 121 * @HB_OT_MATH_CONSTANT_RADICAL_RULE_THICKNESS: radicalRuleThickness 122 * @HB_OT_MATH_CONSTANT_RADICAL_EXTRA_ASCENDER: radicalExtraAscender 123 * @HB_OT_MATH_CONSTANT_RADICAL_KERN_BEFORE_DEGREE: radicalKernBeforeDegree 124 * @HB_OT_MATH_CONSTANT_RADICAL_KERN_AFTER_DEGREE: radicalKernAfterDegree 125 * @HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT: radicalDegreeBottomRaisePercent 126 * 127 * The 'MATH' table constants, refer to 128 * [OpenType documentation](https://docs.microsoft.com/en-us/typography/opentype/spec/math#mathconstants-table) 129 * For more explanations. 130 * 131 * Since: 1.3.3 132 */ 133 typedef enum { 134 HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN = 0, 135 HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN = 1, 136 HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT = 2, 137 HB_OT_MATH_CONSTANT_DISPLAY_OPERATOR_MIN_HEIGHT = 3, 138 HB_OT_MATH_CONSTANT_MATH_LEADING = 4, 139 HB_OT_MATH_CONSTANT_AXIS_HEIGHT = 5, 140 HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT = 6, 141 HB_OT_MATH_CONSTANT_FLATTENED_ACCENT_BASE_HEIGHT = 7, 142 HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN = 8, 143 HB_OT_MATH_CONSTANT_SUBSCRIPT_TOP_MAX = 9, 144 HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN = 10, 145 HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP = 11, 146 HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED = 12, 147 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MIN = 13, 148 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX = 14, 149 HB_OT_MATH_CONSTANT_SUB_SUPERSCRIPT_GAP_MIN = 15, 150 HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MAX_WITH_SUBSCRIPT = 16, 151 HB_OT_MATH_CONSTANT_SPACE_AFTER_SCRIPT = 17, 152 HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN = 18, 153 HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN = 19, 154 HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN = 20, 155 HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN = 21, 156 HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP = 22, 157 HB_OT_MATH_CONSTANT_STACK_TOP_DISPLAY_STYLE_SHIFT_UP = 23, 158 HB_OT_MATH_CONSTANT_STACK_BOTTOM_SHIFT_DOWN = 24, 159 HB_OT_MATH_CONSTANT_STACK_BOTTOM_DISPLAY_STYLE_SHIFT_DOWN = 25, 160 HB_OT_MATH_CONSTANT_STACK_GAP_MIN = 26, 161 HB_OT_MATH_CONSTANT_STACK_DISPLAY_STYLE_GAP_MIN = 27, 162 HB_OT_MATH_CONSTANT_STRETCH_STACK_TOP_SHIFT_UP = 28, 163 HB_OT_MATH_CONSTANT_STRETCH_STACK_BOTTOM_SHIFT_DOWN = 29, 164 HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_ABOVE_MIN = 30, 165 HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_BELOW_MIN = 31, 166 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP = 32, 167 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP = 33, 168 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN = 34, 169 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN = 35, 170 HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_GAP_MIN = 36, 171 HB_OT_MATH_CONSTANT_FRACTION_NUM_DISPLAY_STYLE_GAP_MIN = 37, 172 HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS = 38, 173 HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_GAP_MIN = 39, 174 HB_OT_MATH_CONSTANT_FRACTION_DENOM_DISPLAY_STYLE_GAP_MIN = 40, 175 HB_OT_MATH_CONSTANT_SKEWED_FRACTION_HORIZONTAL_GAP = 41, 176 HB_OT_MATH_CONSTANT_SKEWED_FRACTION_VERTICAL_GAP = 42, 177 HB_OT_MATH_CONSTANT_OVERBAR_VERTICAL_GAP = 43, 178 HB_OT_MATH_CONSTANT_OVERBAR_RULE_THICKNESS = 44, 179 HB_OT_MATH_CONSTANT_OVERBAR_EXTRA_ASCENDER = 45, 180 HB_OT_MATH_CONSTANT_UNDERBAR_VERTICAL_GAP = 46, 181 HB_OT_MATH_CONSTANT_UNDERBAR_RULE_THICKNESS = 47, 182 HB_OT_MATH_CONSTANT_UNDERBAR_EXTRA_DESCENDER = 48, 183 HB_OT_MATH_CONSTANT_RADICAL_VERTICAL_GAP = 49, 184 HB_OT_MATH_CONSTANT_RADICAL_DISPLAY_STYLE_VERTICAL_GAP = 50, 185 HB_OT_MATH_CONSTANT_RADICAL_RULE_THICKNESS = 51, 186 HB_OT_MATH_CONSTANT_RADICAL_EXTRA_ASCENDER = 52, 187 HB_OT_MATH_CONSTANT_RADICAL_KERN_BEFORE_DEGREE = 53, 188 HB_OT_MATH_CONSTANT_RADICAL_KERN_AFTER_DEGREE = 54, 189 HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT = 55 190 } hb_ot_math_constant_t; 191 192 /** 193 * hb_ot_math_kern_t: 194 * @HB_OT_MATH_KERN_TOP_RIGHT: The top right corner of the glyph. 195 * @HB_OT_MATH_KERN_TOP_LEFT: The top left corner of the glyph. 196 * @HB_OT_MATH_KERN_BOTTOM_RIGHT: The bottom right corner of the glyph. 197 * @HB_OT_MATH_KERN_BOTTOM_LEFT: The bottom left corner of the glyph. 198 * 199 * The math kerning-table types defined for the four corners 200 * of a glyph. 201 * 202 * Since: 1.3.3 203 */ 204 typedef enum { 205 HB_OT_MATH_KERN_TOP_RIGHT = 0, 206 HB_OT_MATH_KERN_TOP_LEFT = 1, 207 HB_OT_MATH_KERN_BOTTOM_RIGHT = 2, 208 HB_OT_MATH_KERN_BOTTOM_LEFT = 3 209 } hb_ot_math_kern_t; 210 211 /** 212 * hb_ot_math_kern_entry_t: 213 * @max_correction_height: The maximum height at which this entry should be used 214 * @kern_value: The kern value of the entry 215 * 216 * Data type to hold math kerning (cut-in) information for a glyph. 217 * 218 * Since: 3.4.0 219 */ 220 typedef struct { 221 hb_position_t max_correction_height; 222 hb_position_t kern_value; 223 } hb_ot_math_kern_entry_t; 224 225 /** 226 * hb_ot_math_glyph_variant_t: 227 * @glyph: The glyph index of the variant 228 * @advance: The advance width of the variant 229 * 230 * Data type to hold math-variant information for a glyph. 231 * 232 * Since: 1.3.3 233 */ 234 typedef struct hb_ot_math_glyph_variant_t { 235 hb_codepoint_t glyph; 236 hb_position_t advance; 237 } hb_ot_math_glyph_variant_t; 238 239 /** 240 * hb_ot_math_glyph_part_flags_t: 241 * @HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER: This is an extender glyph part that 242 * can be repeated to reach the desired length. 243 * 244 * Flags for math glyph parts. 245 * 246 * Since: 1.3.3 247 */ 248 typedef enum { /*< flags >*/ 249 HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER = 0x00000001u /* Extender glyph */ 250 } hb_ot_math_glyph_part_flags_t; 251 252 /** 253 * hb_ot_math_glyph_part_t: 254 * @glyph: The glyph index of the variant part 255 * @start_connector_length: The length of the connector on the starting side of the variant part 256 * @end_connector_length: The length of the connector on the ending side of the variant part 257 * @full_advance: The total advance of the part 258 * @flags: #hb_ot_math_glyph_part_flags_t flags for the part 259 * 260 * Data type to hold information for a "part" component of a math-variant glyph. 261 * Large variants for stretchable math glyphs (such as parentheses) can be constructed 262 * on the fly from parts. 263 * 264 * Since: 1.3.3 265 */ 266 typedef struct hb_ot_math_glyph_part_t { 267 hb_codepoint_t glyph; 268 hb_position_t start_connector_length; 269 hb_position_t end_connector_length; 270 hb_position_t full_advance; 271 hb_ot_math_glyph_part_flags_t flags; 272 } hb_ot_math_glyph_part_t; 273 274 /* Methods */ 275 276 HB_EXTERN hb_bool_t 277 hb_ot_math_has_data (hb_face_t *face); 278 279 HB_EXTERN hb_position_t 280 hb_ot_math_get_constant (hb_font_t *font, 281 hb_ot_math_constant_t constant); 282 283 HB_EXTERN hb_position_t 284 hb_ot_math_get_glyph_italics_correction (hb_font_t *font, 285 hb_codepoint_t glyph); 286 287 HB_EXTERN hb_position_t 288 hb_ot_math_get_glyph_top_accent_attachment (hb_font_t *font, 289 hb_codepoint_t glyph); 290 291 HB_EXTERN hb_bool_t 292 hb_ot_math_is_glyph_extended_shape (hb_face_t *face, 293 hb_codepoint_t glyph); 294 295 HB_EXTERN hb_position_t 296 hb_ot_math_get_glyph_kerning (hb_font_t *font, 297 hb_codepoint_t glyph, 298 hb_ot_math_kern_t kern, 299 hb_position_t correction_height); 300 301 HB_EXTERN unsigned int 302 hb_ot_math_get_glyph_kernings (hb_font_t *font, 303 hb_codepoint_t glyph, 304 hb_ot_math_kern_t kern, 305 unsigned int start_offset, 306 unsigned int *entries_count, /* IN/OUT */ 307 hb_ot_math_kern_entry_t *kern_entries /* OUT */); 308 309 HB_EXTERN unsigned int 310 hb_ot_math_get_glyph_variants (hb_font_t *font, 311 hb_codepoint_t glyph, 312 hb_direction_t direction, 313 unsigned int start_offset, 314 unsigned int *variants_count, /* IN/OUT */ 315 hb_ot_math_glyph_variant_t *variants /* OUT */); 316 317 HB_EXTERN hb_position_t 318 hb_ot_math_get_min_connector_overlap (hb_font_t *font, 319 hb_direction_t direction); 320 321 HB_EXTERN unsigned int 322 hb_ot_math_get_glyph_assembly (hb_font_t *font, 323 hb_codepoint_t glyph, 324 hb_direction_t direction, 325 unsigned int start_offset, 326 unsigned int *parts_count, /* IN/OUT */ 327 hb_ot_math_glyph_part_t *parts, /* OUT */ 328 hb_position_t *italics_correction /* OUT */); 329 330 331 HB_END_DECLS 332 333 #endif /* HB_OT_MATH_H */