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/*
* Copyright © 2019 Ebrahim Byagowi
*
* 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.
*/
#if !defined(HB_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
#error "Include <hb.h> instead."
#endif
#ifndef HB_STYLE_H
#define HB_STYLE_H
#include "hb.h"
HB_BEGIN_DECLS
/**
* hb_style_tag_t:
* @HB_STYLE_TAG_ITALIC: Used to vary between non-italic and italic.
* A value of 0 can be interpreted as "Roman" (non-italic); a value of 1 can
* be interpreted as (fully) italic.
* @HB_STYLE_TAG_OPTICAL_SIZE: Used to vary design to suit different text sizes.
* Non-zero. Values can be interpreted as text size, in points.
* @HB_STYLE_TAG_SLANT_ANGLE: Used to vary between upright and slanted text. Values
* must be greater than -90 and less than +90. Values can be interpreted as
* the angle, in counter-clockwise degrees, of oblique slant from whatever the
* designer considers to be upright for that font design. Typical right-leaning
* Italic fonts have a negative slant angle (typically around -12)
* @HB_STYLE_TAG_SLANT_RATIO: same as @HB_STYLE_TAG_SLANT_ANGLE expression as ratio.
* Typical right-leaning Italic fonts have a positive slant ratio (typically around 0.2)
* @HB_STYLE_TAG_WIDTH: Used to vary width of text from narrower to wider.
* Non-zero. Values can be interpreted as a percentage of whatever the font
* designer considers “normal width” for that font design.
* @HB_STYLE_TAG_WEIGHT: Used to vary stroke thicknesses or other design details
* to give variation from lighter to blacker. Values can be interpreted in direct
* comparison to values for usWeightClass in the OS/2 table,
* or the CSS font-weight property.
*
* Defined by [OpenType Design-Variation Axis Tag Registry](https://docs.microsoft.com/en-us/typography/opentype/spec/dvaraxisreg).
*
* Since: 3.0.0
**/
typedef enum
{
HB_STYLE_TAG_ITALIC = HB_TAG ('i','t','a','l'),
HB_STYLE_TAG_OPTICAL_SIZE = HB_TAG ('o','p','s','z'),
HB_STYLE_TAG_SLANT_ANGLE = HB_TAG ('s','l','n','t'),
HB_STYLE_TAG_SLANT_RATIO = HB_TAG ('S','l','n','t'),
HB_STYLE_TAG_WIDTH = HB_TAG ('w','d','t','h'),
HB_STYLE_TAG_WEIGHT = HB_TAG ('w','g','h','t'),
/*< private >*/
_HB_STYLE_TAG_MAX_VALUE = HB_TAG_MAX_SIGNED /*< skip >*/
} hb_style_tag_t;
HB_EXTERN float
hb_style_get_value (hb_font_t *font, hb_style_tag_t style_tag);
HB_END_DECLS
#endif /* HB_STYLE_H */
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