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/*
* Copyright (C) 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @addtogroup Font
* @{
*/
/**
* @file font.h
* @brief Provides some constants used in system_fonts.h or fonts_matcher.h
*
* Available since API level 29.
*/
#ifndef ANDROID_FONT_H
#define ANDROID_FONT_H
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <sys/cdefs.h>
/******************************************************************
*
* IMPORTANT NOTICE:
*
* This file is part of Android's set of stable system headers
* exposed by the Android NDK (Native Development Kit).
*
* Third-party source AND binary code relies on the definitions
* here to be FROZEN ON ALL UPCOMING PLATFORM RELEASES.
*
* - DO NOT MODIFY ENUMS (EXCEPT IF YOU ADD NEW 32-BIT VALUES)
* - DO NOT MODIFY CONSTANTS OR FUNCTIONAL MACROS
* - DO NOT CHANGE THE SIGNATURE OF FUNCTIONS IN ANY WAY
* - DO NOT CHANGE THE LAYOUT OR SIZE OF STRUCTURES
*/
__BEGIN_DECLS
enum {
/** The minimum value fot the font weight value. */
AFONT_WEIGHT_MIN = 0,
/** A font weight value for the thin weight. */
AFONT_WEIGHT_THIN = 100,
/** A font weight value for the extra-light weight. */
AFONT_WEIGHT_EXTRA_LIGHT = 200,
/** A font weight value for the light weight. */
AFONT_WEIGHT_LIGHT = 300,
/** A font weight value for the normal weight. */
AFONT_WEIGHT_NORMAL = 400,
/** A font weight value for the medium weight. */
AFONT_WEIGHT_MEDIUM = 500,
/** A font weight value for the semi-bold weight. */
AFONT_WEIGHT_SEMI_BOLD = 600,
/** A font weight value for the bold weight. */
AFONT_WEIGHT_BOLD = 700,
/** A font weight value for the extra-bold weight. */
AFONT_WEIGHT_EXTRA_BOLD = 800,
/** A font weight value for the black weight. */
AFONT_WEIGHT_BLACK = 900,
/** The maximum value for the font weight value. */
AFONT_WEIGHT_MAX = 1000
};
struct AFont;
/**
* AFont provides information of the single font configuration.
*/
typedef struct AFont AFont;
/**
* Close an AFont.
*
* Available since API level 29.
*
* \param font a font returned by ASystemFontIterator_next or AFontMatchert_match.
* Do nothing if NULL is passed.
*/
void AFont_close(AFont* _Nullable font) __INTRODUCED_IN(29);
/**
* Return an absolute path to the current font file.
*
* Here is a list of font formats returned by this method:
* <ul>
* <li>OpenType</li>
* <li>OpenType Font Collection</li>
* <li>TrueType</li>
* <li>TrueType Collection</li>
* </ul>
* The file extension could be one of *.otf, *.ttf, *.otc or *.ttc.
*
* The font file returned is guaranteed to be opend with O_RDONLY.
* Note that the returned pointer is valid until AFont_close() is called for the given font.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return a string of the font file path.
*/
const char* _Nonnull AFont_getFontFilePath(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return a weight value associated with the current font.
*
* The weight values are positive and less than or equal to 1000.
* Here are pairs of the common names and their values.
* <p>
* <table>
* <tr>
* <th align="center">Value</th>
* <th align="center">Name</th>
* <th align="center">NDK Definition</th>
* </tr>
* <tr>
* <td align="center">100</td>
* <td align="center">Thin</td>
* <td align="center">{@link AFONT_WEIGHT_THIN}</td>
* </tr>
* <tr>
* <td align="center">200</td>
* <td align="center">Extra Light (Ultra Light)</td>
* <td align="center">{@link AFONT_WEIGHT_EXTRA_LIGHT}</td>
* </tr>
* <tr>
* <td align="center">300</td>
* <td align="center">Light</td>
* <td align="center">{@link AFONT_WEIGHT_LIGHT}</td>
* </tr>
* <tr>
* <td align="center">400</td>
* <td align="center">Normal (Regular)</td>
* <td align="center">{@link AFONT_WEIGHT_NORMAL}</td>
* </tr>
* <tr>
* <td align="center">500</td>
* <td align="center">Medium</td>
* <td align="center">{@link AFONT_WEIGHT_MEDIUM}</td>
* </tr>
* <tr>
* <td align="center">600</td>
* <td align="center">Semi Bold (Demi Bold)</td>
* <td align="center">{@link AFONT_WEIGHT_SEMI_BOLD}</td>
* </tr>
* <tr>
* <td align="center">700</td>
* <td align="center">Bold</td>
* <td align="center">{@link AFONT_WEIGHT_BOLD}</td>
* </tr>
* <tr>
* <td align="center">800</td>
* <td align="center">Extra Bold (Ultra Bold)</td>
* <td align="center">{@link AFONT_WEIGHT_EXTRA_BOLD}</td>
* </tr>
* <tr>
* <td align="center">900</td>
* <td align="center">Black (Heavy)</td>
* <td align="center">{@link AFONT_WEIGHT_BLACK}</td>
* </tr>
* </table>
* </p>
* Note that the weight value may fall in between above values, e.g. 250 weight.
*
* For more information about font weight, read [OpenType usWeightClass](https://docs.microsoft.com/en-us/typography/opentype/spec/os2#usweightclass)
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return a positive integer less than or equal to {@link AFONT_WEIGHT_MAX} is returned.
*/
uint16_t AFont_getWeight(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return true if the current font is italic, otherwise returns false.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return true if italic, otherwise false.
*/
bool AFont_isItalic(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return a IETF BCP47 compliant language tag associated with the current font.
*
* For information about IETF BCP47, read [Locale.forLanguageTag(java.lang.String)](https://developer.android.com/reference/java/util/Locale.html#forLanguageTag(java.lang.String)")
*
* Note that the returned pointer is valid until AFont_close() is called.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return a IETF BCP47 compliant language tag or nullptr if not available.
*/
const char* _Nullable AFont_getLocale(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return a font collection index value associated with the current font.
*
* In case the target font file is a font collection (e.g. .ttc or .otc), this
* returns a non-negative value as an font offset in the collection. This
* always returns 0 if the target font file is a regular font.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return a font collection index.
*/
size_t AFont_getCollectionIndex(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return a count of font variation settings associated with the current font
*
* The font variation settings are provided as multiple tag-values pairs.
*
* For example, bold italic font may have following font variation settings:
* 'wght' 700, 'slnt' -12
* In this case, AFont_getAxisCount returns 2 and AFont_getAxisTag
* and AFont_getAxisValue will return following values.
* \code{.cpp}
* AFont* font = ASystemFontIterator_next(ite);
*
* // Returns the number of axes
* AFont_getAxisCount(font); // Returns 2
*
* // Returns the tag-value pair for the first axis.
* AFont_getAxisTag(font, 0); // Returns 'wght'(0x77676874)
* AFont_getAxisValue(font, 0); // Returns 700.0
*
* // Returns the tag-value pair for the second axis.
* AFont_getAxisTag(font, 1); // Returns 'slnt'(0x736c6e74)
* AFont_getAxisValue(font, 1); // Returns -12.0
* \endcode
*
* For more information about font variation settings, read [Font Variations Table](https://docs.microsoft.com/en-us/typography/opentype/spec/fvar)
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \return a number of font variation settings.
*/
size_t AFont_getAxisCount(const AFont* _Nonnull font) __INTRODUCED_IN(29);
/**
* Return an OpenType axis tag associated with the current font.
*
* See AFont_getAxisCount for more details.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \param axisIndex an index to the font variation settings. Passing value larger than or
* equal to {@link AFont_getAxisCount} is not allowed.
* \return an OpenType axis tag value for the given font variation setting.
*/
uint32_t AFont_getAxisTag(const AFont* _Nonnull font, uint32_t axisIndex)
__INTRODUCED_IN(29);
/**
* Return an OpenType axis value associated with the current font.
*
* See AFont_getAxisCount for more details.
*
* Available since API level 29.
*
* \param font a font object. Passing NULL is not allowed.
* \param axisIndex an index to the font variation settings. Passing value larger than or
* equal to {@link AFont_getAxisCount} is not allowed.
* \return a float value for the given font variation setting.
*/
float AFont_getAxisValue(const AFont* _Nonnull font, uint32_t axisIndex)
__INTRODUCED_IN(29);
__END_DECLS
#endif // ANDROID_FONT_H
/** @} */