HarfBuzz text shaping engine http://harfbuzz.github.io/
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/*
* Copyright © 2016 Igalia S.L.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Igalia Author(s): Frédéric Wang
*/
#if !defined(HB_OT_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
#error "Include <hb-ot.h> instead."
#endif
#ifndef HB_OT_MATH_H
#define HB_OT_MATH_H
#include "hb.h"
HB_BEGIN_DECLS
/*
* MATH
*/
/**
* HB_OT_TAG_MATH:
*
* OpenType [Mathematical Typesetting Table](https://docs.microsoft.com/en-us/typography/opentype/spec/math).
*
* Since: 1.3.3
*/
#define HB_OT_TAG_MATH HB_TAG('M','A','T','H')
/**
* HB_OT_TAG_MATH_SCRIPT:
*
* OpenType script tag, `math`, for features specific to math shaping.
*
* <note>#HB_OT_TAG_MATH_SCRIPT is not a valid #hb_script_t and should only be
* used with functions that accept raw OpenType script tags, such as
* #hb_ot_layout_collect_features. In other cases, #HB_SCRIPT_MATH should be
* used instead.</note>
*
* Since: 3.4.0
*/
#define HB_OT_TAG_MATH_SCRIPT HB_TAG('m','a','t','h')
/* Types */
/**
* hb_ot_math_constant_t:
* @HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN: scriptPercentScaleDown
* @HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN: scriptScriptPercentScaleDown
* @HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT: delimitedSubFormulaMinHeight
* @HB_OT_MATH_CONSTANT_DISPLAY_OPERATOR_MIN_HEIGHT: displayOperatorMinHeight
* @HB_OT_MATH_CONSTANT_MATH_LEADING: mathLeading
* @HB_OT_MATH_CONSTANT_AXIS_HEIGHT: axisHeight
* @HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT: accentBaseHeight
* @HB_OT_MATH_CONSTANT_FLATTENED_ACCENT_BASE_HEIGHT: flattenedAccentBaseHeight
* @HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN: subscriptShiftDown
* @HB_OT_MATH_CONSTANT_SUBSCRIPT_TOP_MAX: subscriptTopMax
* @HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN: subscriptBaselineDropMin
* @HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP: superscriptShiftUp
* @HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED: superscriptShiftUpCramped
* @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MIN: superscriptBottomMin
* @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX: superscriptBaselineDropMax
* @HB_OT_MATH_CONSTANT_SUB_SUPERSCRIPT_GAP_MIN: subSuperscriptGapMin
* @HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MAX_WITH_SUBSCRIPT: superscriptBottomMaxWithSubscript
* @HB_OT_MATH_CONSTANT_SPACE_AFTER_SCRIPT: spaceAfterScript
* @HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN: upperLimitGapMin
* @HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN: upperLimitBaselineRiseMin
* @HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN: lowerLimitGapMin
* @HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN: lowerLimitBaselineDropMin
* @HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP: stackTopShiftUp
* @HB_OT_MATH_CONSTANT_STACK_TOP_DISPLAY_STYLE_SHIFT_UP: stackTopDisplayStyleShiftUp
* @HB_OT_MATH_CONSTANT_STACK_BOTTOM_SHIFT_DOWN: stackBottomShiftDown
* @HB_OT_MATH_CONSTANT_STACK_BOTTOM_DISPLAY_STYLE_SHIFT_DOWN: stackBottomDisplayStyleShiftDown
* @HB_OT_MATH_CONSTANT_STACK_GAP_MIN: stackGapMin
* @HB_OT_MATH_CONSTANT_STACK_DISPLAY_STYLE_GAP_MIN: stackDisplayStyleGapMin
* @HB_OT_MATH_CONSTANT_STRETCH_STACK_TOP_SHIFT_UP: stretchStackTopShiftUp
* @HB_OT_MATH_CONSTANT_STRETCH_STACK_BOTTOM_SHIFT_DOWN: stretchStackBottomShiftDown
* @HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_ABOVE_MIN: stretchStackGapAboveMin
* @HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_BELOW_MIN: stretchStackGapBelowMin
* @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP: fractionNumeratorShiftUp
* @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP: fractionNumeratorDisplayStyleShiftUp
* @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN: fractionDenominatorShiftDown
* @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN: fractionDenominatorDisplayStyleShiftDown
* @HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_GAP_MIN: fractionNumeratorGapMin
* @HB_OT_MATH_CONSTANT_FRACTION_NUM_DISPLAY_STYLE_GAP_MIN: fractionNumDisplayStyleGapMin
* @HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS: fractionRuleThickness
* @HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_GAP_MIN: fractionDenominatorGapMin
* @HB_OT_MATH_CONSTANT_FRACTION_DENOM_DISPLAY_STYLE_GAP_MIN: fractionDenomDisplayStyleGapMin
* @HB_OT_MATH_CONSTANT_SKEWED_FRACTION_HORIZONTAL_GAP: skewedFractionHorizontalGap
* @HB_OT_MATH_CONSTANT_SKEWED_FRACTION_VERTICAL_GAP: skewedFractionVerticalGap
* @HB_OT_MATH_CONSTANT_OVERBAR_VERTICAL_GAP: overbarVerticalGap
* @HB_OT_MATH_CONSTANT_OVERBAR_RULE_THICKNESS: overbarRuleThickness
* @HB_OT_MATH_CONSTANT_OVERBAR_EXTRA_ASCENDER: overbarExtraAscender
* @HB_OT_MATH_CONSTANT_UNDERBAR_VERTICAL_GAP: underbarVerticalGap
* @HB_OT_MATH_CONSTANT_UNDERBAR_RULE_THICKNESS: underbarRuleThickness
* @HB_OT_MATH_CONSTANT_UNDERBAR_EXTRA_DESCENDER: underbarExtraDescender
* @HB_OT_MATH_CONSTANT_RADICAL_VERTICAL_GAP: radicalVerticalGap
* @HB_OT_MATH_CONSTANT_RADICAL_DISPLAY_STYLE_VERTICAL_GAP: radicalDisplayStyleVerticalGap
* @HB_OT_MATH_CONSTANT_RADICAL_RULE_THICKNESS: radicalRuleThickness
* @HB_OT_MATH_CONSTANT_RADICAL_EXTRA_ASCENDER: radicalExtraAscender
* @HB_OT_MATH_CONSTANT_RADICAL_KERN_BEFORE_DEGREE: radicalKernBeforeDegree
* @HB_OT_MATH_CONSTANT_RADICAL_KERN_AFTER_DEGREE: radicalKernAfterDegree
* @HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT: radicalDegreeBottomRaisePercent
*
* The 'MATH' table constants, refer to
* [OpenType documentation](https://docs.microsoft.com/en-us/typography/opentype/spec/math#mathconstants-table)
* For more explanations.
*
* Since: 1.3.3
*/
typedef enum {
HB_OT_MATH_CONSTANT_SCRIPT_PERCENT_SCALE_DOWN = 0,
HB_OT_MATH_CONSTANT_SCRIPT_SCRIPT_PERCENT_SCALE_DOWN = 1,
HB_OT_MATH_CONSTANT_DELIMITED_SUB_FORMULA_MIN_HEIGHT = 2,
HB_OT_MATH_CONSTANT_DISPLAY_OPERATOR_MIN_HEIGHT = 3,
HB_OT_MATH_CONSTANT_MATH_LEADING = 4,
HB_OT_MATH_CONSTANT_AXIS_HEIGHT = 5,
HB_OT_MATH_CONSTANT_ACCENT_BASE_HEIGHT = 6,
HB_OT_MATH_CONSTANT_FLATTENED_ACCENT_BASE_HEIGHT = 7,
HB_OT_MATH_CONSTANT_SUBSCRIPT_SHIFT_DOWN = 8,
HB_OT_MATH_CONSTANT_SUBSCRIPT_TOP_MAX = 9,
HB_OT_MATH_CONSTANT_SUBSCRIPT_BASELINE_DROP_MIN = 10,
HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP = 11,
HB_OT_MATH_CONSTANT_SUPERSCRIPT_SHIFT_UP_CRAMPED = 12,
HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MIN = 13,
HB_OT_MATH_CONSTANT_SUPERSCRIPT_BASELINE_DROP_MAX = 14,
HB_OT_MATH_CONSTANT_SUB_SUPERSCRIPT_GAP_MIN = 15,
HB_OT_MATH_CONSTANT_SUPERSCRIPT_BOTTOM_MAX_WITH_SUBSCRIPT = 16,
HB_OT_MATH_CONSTANT_SPACE_AFTER_SCRIPT = 17,
HB_OT_MATH_CONSTANT_UPPER_LIMIT_GAP_MIN = 18,
HB_OT_MATH_CONSTANT_UPPER_LIMIT_BASELINE_RISE_MIN = 19,
HB_OT_MATH_CONSTANT_LOWER_LIMIT_GAP_MIN = 20,
HB_OT_MATH_CONSTANT_LOWER_LIMIT_BASELINE_DROP_MIN = 21,
HB_OT_MATH_CONSTANT_STACK_TOP_SHIFT_UP = 22,
HB_OT_MATH_CONSTANT_STACK_TOP_DISPLAY_STYLE_SHIFT_UP = 23,
HB_OT_MATH_CONSTANT_STACK_BOTTOM_SHIFT_DOWN = 24,
HB_OT_MATH_CONSTANT_STACK_BOTTOM_DISPLAY_STYLE_SHIFT_DOWN = 25,
HB_OT_MATH_CONSTANT_STACK_GAP_MIN = 26,
HB_OT_MATH_CONSTANT_STACK_DISPLAY_STYLE_GAP_MIN = 27,
HB_OT_MATH_CONSTANT_STRETCH_STACK_TOP_SHIFT_UP = 28,
HB_OT_MATH_CONSTANT_STRETCH_STACK_BOTTOM_SHIFT_DOWN = 29,
HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_ABOVE_MIN = 30,
HB_OT_MATH_CONSTANT_STRETCH_STACK_GAP_BELOW_MIN = 31,
HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_SHIFT_UP = 32,
HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_DISPLAY_STYLE_SHIFT_UP = 33,
HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_SHIFT_DOWN = 34,
HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_DISPLAY_STYLE_SHIFT_DOWN = 35,
HB_OT_MATH_CONSTANT_FRACTION_NUMERATOR_GAP_MIN = 36,
HB_OT_MATH_CONSTANT_FRACTION_NUM_DISPLAY_STYLE_GAP_MIN = 37,
HB_OT_MATH_CONSTANT_FRACTION_RULE_THICKNESS = 38,
HB_OT_MATH_CONSTANT_FRACTION_DENOMINATOR_GAP_MIN = 39,
HB_OT_MATH_CONSTANT_FRACTION_DENOM_DISPLAY_STYLE_GAP_MIN = 40,
HB_OT_MATH_CONSTANT_SKEWED_FRACTION_HORIZONTAL_GAP = 41,
HB_OT_MATH_CONSTANT_SKEWED_FRACTION_VERTICAL_GAP = 42,
HB_OT_MATH_CONSTANT_OVERBAR_VERTICAL_GAP = 43,
HB_OT_MATH_CONSTANT_OVERBAR_RULE_THICKNESS = 44,
HB_OT_MATH_CONSTANT_OVERBAR_EXTRA_ASCENDER = 45,
HB_OT_MATH_CONSTANT_UNDERBAR_VERTICAL_GAP = 46,
HB_OT_MATH_CONSTANT_UNDERBAR_RULE_THICKNESS = 47,
HB_OT_MATH_CONSTANT_UNDERBAR_EXTRA_DESCENDER = 48,
HB_OT_MATH_CONSTANT_RADICAL_VERTICAL_GAP = 49,
HB_OT_MATH_CONSTANT_RADICAL_DISPLAY_STYLE_VERTICAL_GAP = 50,
HB_OT_MATH_CONSTANT_RADICAL_RULE_THICKNESS = 51,
HB_OT_MATH_CONSTANT_RADICAL_EXTRA_ASCENDER = 52,
HB_OT_MATH_CONSTANT_RADICAL_KERN_BEFORE_DEGREE = 53,
HB_OT_MATH_CONSTANT_RADICAL_KERN_AFTER_DEGREE = 54,
HB_OT_MATH_CONSTANT_RADICAL_DEGREE_BOTTOM_RAISE_PERCENT = 55
} hb_ot_math_constant_t;
/**
* hb_ot_math_kern_t:
* @HB_OT_MATH_KERN_TOP_RIGHT: The top right corner of the glyph.
* @HB_OT_MATH_KERN_TOP_LEFT: The top left corner of the glyph.
* @HB_OT_MATH_KERN_BOTTOM_RIGHT: The bottom right corner of the glyph.
* @HB_OT_MATH_KERN_BOTTOM_LEFT: The bottom left corner of the glyph.
*
* The math kerning-table types defined for the four corners
* of a glyph.
*
* Since: 1.3.3
*/
typedef enum {
HB_OT_MATH_KERN_TOP_RIGHT = 0,
HB_OT_MATH_KERN_TOP_LEFT = 1,
HB_OT_MATH_KERN_BOTTOM_RIGHT = 2,
HB_OT_MATH_KERN_BOTTOM_LEFT = 3
} hb_ot_math_kern_t;
/**
* hb_ot_math_kern_entry_t:
* @max_correction_height: The maximum height at which this entry should be used
* @kern_value: The kern value of the entry
*
* Data type to hold math kerning (cut-in) information for a glyph.
*
* Since: 3.4.0
*/
typedef struct {
hb_position_t max_correction_height;
hb_position_t kern_value;
} hb_ot_math_kern_entry_t;
/**
* hb_ot_math_glyph_variant_t:
* @glyph: The glyph index of the variant
* @advance: The advance width of the variant
*
* Data type to hold math-variant information for a glyph.
*
* Since: 1.3.3
*/
typedef struct hb_ot_math_glyph_variant_t {
hb_codepoint_t glyph;
hb_position_t advance;
} hb_ot_math_glyph_variant_t;
/**
* hb_ot_math_glyph_part_flags_t:
* @HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER: This is an extender glyph part that
* can be repeated to reach the desired length.
*
* Flags for math glyph parts.
*
* Since: 1.3.3
*/
typedef enum { /*< flags >*/
HB_OT_MATH_GLYPH_PART_FLAG_EXTENDER = 0x00000001u /* Extender glyph */
} hb_ot_math_glyph_part_flags_t;
/**
* hb_ot_math_glyph_part_t:
* @glyph: The glyph index of the variant part
* @start_connector_length: The length of the connector on the starting side of the variant part
* @end_connector_length: The length of the connector on the ending side of the variant part
* @full_advance: The total advance of the part
* @flags: #hb_ot_math_glyph_part_flags_t flags for the part
*
* Data type to hold information for a "part" component of a math-variant glyph.
* Large variants for stretchable math glyphs (such as parentheses) can be constructed
* on the fly from parts.
*
* Since: 1.3.3
*/
typedef struct hb_ot_math_glyph_part_t {
hb_codepoint_t glyph;
hb_position_t start_connector_length;
hb_position_t end_connector_length;
hb_position_t full_advance;
hb_ot_math_glyph_part_flags_t flags;
} hb_ot_math_glyph_part_t;
/* Methods */
HB_EXTERN hb_bool_t
hb_ot_math_has_data (hb_face_t *face);
HB_EXTERN hb_position_t
hb_ot_math_get_constant (hb_font_t *font,
hb_ot_math_constant_t constant);
HB_EXTERN hb_position_t
hb_ot_math_get_glyph_italics_correction (hb_font_t *font,
hb_codepoint_t glyph);
HB_EXTERN hb_position_t
hb_ot_math_get_glyph_top_accent_attachment (hb_font_t *font,
hb_codepoint_t glyph);
HB_EXTERN hb_bool_t
hb_ot_math_is_glyph_extended_shape (hb_face_t *face,
hb_codepoint_t glyph);
HB_EXTERN hb_position_t
hb_ot_math_get_glyph_kerning (hb_font_t *font,
hb_codepoint_t glyph,
hb_ot_math_kern_t kern,
hb_position_t correction_height);
HB_EXTERN unsigned int
hb_ot_math_get_glyph_kernings (hb_font_t *font,
hb_codepoint_t glyph,
hb_ot_math_kern_t kern,
unsigned int start_offset,
unsigned int *entries_count, /* IN/OUT */
hb_ot_math_kern_entry_t *kern_entries /* OUT */);
HB_EXTERN unsigned int
hb_ot_math_get_glyph_variants (hb_font_t *font,
hb_codepoint_t glyph,
hb_direction_t direction,
unsigned int start_offset,
unsigned int *variants_count, /* IN/OUT */
hb_ot_math_glyph_variant_t *variants /* OUT */);
HB_EXTERN hb_position_t
hb_ot_math_get_min_connector_overlap (hb_font_t *font,
hb_direction_t direction);
HB_EXTERN unsigned int
hb_ot_math_get_glyph_assembly (hb_font_t *font,
hb_codepoint_t glyph,
hb_direction_t direction,
unsigned int start_offset,
unsigned int *parts_count, /* IN/OUT */
hb_ot_math_glyph_part_t *parts, /* OUT */
hb_position_t *italics_correction /* OUT */);
HB_END_DECLS
#endif /* HB_OT_MATH_H */