| /* |
| * Copyright (C) 2018 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. |
| */ |
| |
| /** |
| * @file system_fonts.h |
| * @brief Provides the system font configurations. |
| * |
| * These APIs provides the list of system installed font files with additional metadata about the |
| * font. |
| * |
| * The ASystemFontIterator_open method will give you an iterator which can iterate all system |
| * installed font files as shown in the following example. |
| * |
| * \code{.cpp} |
| * ASystemFontIterator* iterator = ASystemFontIterator_open(); |
| * ASystemFont* font = NULL; |
| * |
| * while ((font = ASystemFontIterator_next(iterator)) != nullptr) { |
| * // Look if the font is your desired one. |
| * if (ASystemFont_getWeight(font) == 400 && !ASystemFont_isItalic(font) |
| * && ASystemFont_getLocale(font) == NULL) { |
| * break; |
| * } |
| * ASystemFont_close(font); |
| * } |
| * ASystemFontIterator_close(iterator); |
| * |
| * int fd = open(ASystemFont_getFontFilePath(font), O_RDONLY); |
| * int collectionIndex = ASystemFont_getCollectionINdex(font); |
| * std::vector<std::pair<uint32_t, float>> variationSettings; |
| * for (size_t i = 0; i < ASystemFont_getAxisCount(font); ++i) { |
| * variationSettings.push_back(std::make_pair( |
| * ASystemFont_getAxisTag(font, i), |
| * ASystemFont_getAxisValue(font, i))); |
| * } |
| * ASystemFont_close(font); |
| * |
| * // Use this font for your text rendering engine. |
| * |
| * \endcode |
| * |
| * Available since API level 29. |
| */ |
| |
| #ifndef ANDROID_SYSTEM_FONTS_H |
| #define ANDROID_SYSTEM_FONTS_H |
| |
| #include <stdbool.h> |
| #include <stddef.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 |
| |
| #if __ANDROID_API__ >= 29 |
| |
| enum { |
| /** The minimum value fot the font weight value. */ |
| ASYSTEM_FONT_WEIGHT_MIN = 0, |
| |
| /** A font weight value for the thin weight. */ |
| ASYSTEM_FONT_WEIGHT_THIN = 100, |
| |
| /** A font weight value for the extra-light weight. */ |
| ASYSTEM_FONT_WEIGHT_EXTRA_LIGHT = 200, |
| |
| /** A font weight value for the light weight. */ |
| ASYSTEM_FONT_WEIGHT_LIGHT = 300, |
| |
| /** A font weight value for the normal weight. */ |
| ASYSTEM_FONT_WEIGHT_NORMAL = 400, |
| |
| /** A font weight value for the medium weight. */ |
| ASYSTEM_FONT_WEIGHT_MEDIUM = 500, |
| |
| /** A font weight value for the semi-bold weight. */ |
| ASYSTEM_FONT_WEIGHT_SEMI_BOLD = 600, |
| |
| /** A font weight value for the bold weight. */ |
| ASYSTEM_FONT_WEIGHT_BOLD = 700, |
| |
| /** A font weight value for the extra-bold weight. */ |
| ASYSTEM_FONT_WEIGHT_EXTRA_BOLD = 800, |
| |
| /** A font weight value for the black weight. */ |
| ASYSTEM_FONT_WEIGHT_BLACK = 900, |
| |
| /** The maximum value for the font weight value. */ |
| ASYSTEM_FONT_WEIGHT_MAX = 1000 |
| }; |
| |
| /** |
| * ASystemFontIterator provides access to the system font configuration. |
| * |
| * ASystemFontIterator is an iterator for all available system font settings. |
| * This iterator is not a thread-safe object. Do not pass this iterator to other threads. |
| */ |
| struct ASystemFontIterator; |
| |
| /** |
| * ASystemFont provides information of the single system font configuration. |
| */ |
| struct ASystemFont; |
| |
| /** |
| * Create a system font iterator. |
| * |
| * Use ASystemFont_close() to close the iterator. |
| * |
| * \return a pointer for a newly allocated iterator, nullptr on failure. |
| */ |
| ASystemFontIterator* _Nullable ASystemFontIterator_open() __INTRODUCED_IN(29); |
| |
| /** |
| * Close an opened system font iterator, freeing any related resources. |
| * |
| * \param iterator a pointer of an iterator for the system fonts. Do nothing if NULL is passed. |
| */ |
| void ASystemFontIterator_close(ASystemFontIterator* _Nullable iterator) __INTRODUCED_IN(29); |
| |
| /** |
| * Move to the next system font. |
| * |
| * \param iterator an iterator for the system fonts. Passing NULL is not allowed. |
| * \return a font. If no more font is available, returns nullptr. You need to release the returned |
| * font by ASystemFont_close when it is no longer needed. |
| */ |
| ASystemFont* _Nullable ASystemFontIterator_next(ASystemFontIterator* _Nonnull iterator) __INTRODUCED_IN(29); |
| |
| /** |
| * Close an ASystemFont returned by ASystemFontIterator_next. |
| * |
| * \param font a font returned by ASystemFontIterator_next or ASystemFont_matchFamilyStyleCharacter. |
| * Do nothing if NULL is passed. |
| */ |
| void ASystemFont_close(ASystemFont* _Nullable font) __INTRODUCED_IN(29); |
| |
| |
| /** |
| * Select the best font from given parameters. |
| * |
| * Only generic font families are supported. |
| * For more information about generic font families, read [W3C spec](https://www.w3.org/TR/css-fonts-4/#generic-font-families) |
| * |
| * Even if no font can render the given text, this function will return a non-null result for |
| * drawing Tofu character. |
| * |
| * Examples: |
| * \code{.cpp} |
| * // Simple font query for the ASCII character. |
| * std::vector<uint16_t> text = { 'A' }; |
| * ASystemFont font = ASystemFont_matchFamilyStyleCharacter( |
| * "sans", 400, false, "en-US", text.data(), text.length(), &runLength); |
| * // runLength will be 1 and the font will points a valid font file. |
| * |
| * // Querying font for CJK characters |
| * std::vector<uint16_t> text = { 0x9AA8 }; |
| * ASystemFont font = ASystemFont_matchFamilyStyleCharacter( |
| * "sans", 400, false, "zh-CN,ja-JP", text.data(), text.length(), &runLength); |
| * // runLength will be 1 and the font will points a Simplified Chinese font. |
| * ASystemFont font = ASystemFont_matchFamilyStyleCharacter( |
| * "sans", 400, false, "ja-JP,zh-CN", text.data(), text.length(), &runLength); |
| * // runLength will be 1 and the font will points a Japanese font. |
| * |
| * // Querying font for text/color emoji |
| * std::vector<uint16_t> text = { 0xD83D, 0xDC68, 0x200D, 0x2764, 0xFE0F, 0x200D, 0xD83D, 0xDC68 }; |
| * ASystemFont font = ASystemFont_matchFamilyStyleCharacter( |
| * "sans", 400, false, "en-US", text.data(), text.length(), &runLength); |
| * // runLength will be 8 and the font will points a color emoji font. |
| * |
| * // Mixture of multiple script of characters. |
| * // 0x05D0 is a Hebrew character and 0x0E01 is a Thai character. |
| * std::vector<uint16_t> text = { 0x05D0, 0x0E01 }; |
| * ASystemFont font = ASystemFont_matchFamilyStyleCharacter( |
| * "sans", 400, false, "en-US", text.data(), text.length(), &runLength); |
| * // runLength will be 1 and the font will points a Hebrew font. |
| * \endcode |
| * |
| * \param familyName a null character terminated font family name |
| * \param weight a font weight value. Only from 0 to 1000 value is valid |
| * \param italic true if italic, otherwise false. |
| * \param languageTags a null character terminated comma separated IETF BCP47 compliant language |
| * tags. |
| * \param text a UTF-16 encoded text buffer to be rendered. Do not pass empty string. |
| * \param textLength a length of the given text buffer. This must not be zero. |
| * \param runLengthOut if not null, the font run length will be filled. |
| * \return a font to be used for given text and params. You need to release the returned font by |
| * ASystemFont_close when it is no longer needed. |
| */ |
| ASystemFont* _Nonnull ASystemFont_matchFamilyStyleCharacter( |
| const char* _Nonnull familyName, |
| uint16_t weight, |
| bool italic, |
| const char* _Nonnull languageTags, |
| const uint16_t* _Nonnull text, |
| uint32_t textLength, |
| uint32_t* _Nullable runLengthOut) __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 ASystemFont_close() is called for the given font. |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return a string of the font file path. |
| */ |
| const char* _Nonnull ASystemFont_getFontFilePath(const ASystemFont* _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 ASYSTEM_FONT_WEIGHT_THIN}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">200</td> |
| * <td align="center">Extra Light (Ultra Light)</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_EXTRA_LIGHT}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">300</td> |
| * <td align="center">Light</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_LIGHT}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">400</td> |
| * <td align="center">Normal (Regular)</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_NORMAL}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">500</td> |
| * <td align="center">Medium</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_MEDIUM}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">600</td> |
| * <td align="center">Semi Bold (Demi Bold)</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_SEMI_BOLD}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">700</td> |
| * <td align="center">Bold</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_BOLD}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">800</td> |
| * <td align="center">Extra Bold (Ultra Bold)</td> |
| * <td align="center">{@link ASYSTEM_FONT_WEIGHT_EXTRA_BOLD}</td> |
| * </tr> |
| * <tr> |
| * <td align="center">900</td> |
| * <td align="center">Black (Heavy)</td> |
| * <td align="center">{@link ASYSTEM_FONT_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) |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return a positive integer less than or equal to {@link ASYSTEM_FONT_MAX_WEIGHT} is returned. |
| */ |
| uint16_t ASystemFont_getWeight(const ASystemFont* _Nonnull font) __INTRODUCED_IN(29); |
| |
| /** |
| * Return true if the current font is italic, otherwise returns false. |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return true if italic, otherwise false. |
| */ |
| bool ASystemFont_isItalic(const ASystemFont* _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 ASystemFont_close() is called. |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return a IETF BCP47 compliant langauge tag or nullptr if not available. |
| */ |
| const char* _Nullable ASystemFont_getLocale(const ASystemFont* _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. |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return a font collection index. |
| */ |
| size_t ASystemFont_getCollectionIndex(const ASystemFont* _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, ASystemFont_getAxisCount returns 2 and ASystemFont_getAxisTag |
| * and ASystemFont_getAxisValue will return following values. |
| * \code{.cpp} |
| * ASystemFont* font = ASystemFontIterator_next(ite); |
| * |
| * // Returns the number of axes |
| * ASystemFont_getAxisCount(font); // Returns 2 |
| * |
| * // Returns the tag-value pair for the first axis. |
| * ASystemFont_getAxisTag(font, 0); // Returns 'wght'(0x77676874) |
| * ASystemFont_getAxisValue(font, 0); // Returns 700.0 |
| * |
| * // Returns the tag-value pair for the second axis. |
| * ASystemFont_getAxisTag(font, 1); // Returns 'slnt'(0x736c6e74) |
| * ASystemFont_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) |
| * |
| * \param font a font object. Passing NULL is not allowed. |
| * \return a number of font variation settings. |
| */ |
| size_t ASystemFont_getAxisCount(const ASystemFont* _Nonnull font) __INTRODUCED_IN(29); |
| |
| |
| /** |
| * Return an OpenType axis tag associated with the current font. |
| * |
| * See ASystemFont_getAxisCount for more details. |
| * |
| * \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 ASystemFont_getAxisCount} is not allowed. |
| * \return an OpenType axis tag value for the given font variation setting. |
| */ |
| uint32_t ASystemFont_getAxisTag(const ASystemFont* _Nonnull font, uint32_t axisIndex) |
| __INTRODUCED_IN(29); |
| |
| /** |
| * Return an OpenType axis value associated with the current font. |
| * |
| * See ASystemFont_getAxisCount for more details. |
| * |
| * \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 ASYstemFont_getAxisCount} is not allwed. |
| * \return a float value for the given font variation setting. |
| */ |
| float ASystemFont_getAxisValue(const ASystemFont* _Nonnull font, uint32_t axisIndex) |
| __INTRODUCED_IN(29); |
| |
| #endif // __ANDROID_API__ >= 29 |
| |
| __END_DECLS |
| |
| #endif // ANDROID_SYSTEM_FONTS_H |