1 #ifndef DALI_PLATFORM_TEXT_ABSTRACTION_FONT_CLIENT_H
2 #define DALI_PLATFORM_TEXT_ABSTRACTION_FONT_CLIENT_H
5 * Copyright (c) 2023 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <dali/devel-api/text-abstraction/font-list.h>
23 #include <dali/devel-api/text-abstraction/glyph-buffer-data.h>
24 #include <dali/devel-api/text-abstraction/text-abstraction-definitions.h>
25 #include <dali/public-api/common/dali-vector.h>
26 #include <dali/public-api/dali-adaptor-common.h>
27 #include <dali/public-api/images/pixel-data.h>
28 #include <dali/public-api/object/base-handle.h>
32 namespace TextAbstraction
38 namespace Internal DALI_INTERNAL
44 * @brief FontClient provides access to font information and resources.
46 * <h3>Querying the System Fonts</h3>
48 * A "system font" is described by a "path" to a font file on the native filesystem, along with a "family" and "style".
49 * For example on the Ubuntu system a "Regular" style font from the "Ubuntu Mono" family can be accessed from "/usr/share/fonts/truetype/ubuntu-font-family/UbuntuMono-R.ttf".
51 * <h3>Accessing Fonts</h3>
53 * A "font" is created from the system for a specific point size in 26.6 fractional points. A "FontId" is used to identify each font.
54 * For example two different fonts with point sizes 10 & 12 can be created from the "Ubuntu Mono" family:
56 * FontClient fontClient = FontClient::Get();
57 * FontId ubuntuMonoTen = fontClient.GetFontId( "/usr/share/fonts/truetype/ubuntu-font-family/UbuntuMono-R.ttf", 10*64 );
58 * FontId ubuntuMonoTwelve = fontClient.GetFontId( "/usr/share/fonts/truetype/ubuntu-font-family/UbuntuMono-R.ttf", 12*64 );
60 * Glyph metrics and bitmap resources can then be retrieved using the FontId.
62 class DALI_ADAPTOR_API FontClient : public BaseHandle
65 static const PointSize26Dot6 DEFAULT_POINT_SIZE; ///< The default point size.
66 static const float DEFAULT_ITALIC_ANGLE; ///< The default software italic angle in radians.
68 static const bool DEFAULT_ATLAS_LIMITATION_ENABLED; ///< The default behavior of whether atlas limitation is enabled in dali.
69 static const uint32_t DEFAULT_TEXT_ATLAS_WIDTH; ///< The default width of text-atlas-block.
70 static const uint32_t DEFAULT_TEXT_ATLAS_HEIGHT; ///< The default height of text-atlas-block.
71 static const Size DEFAULT_TEXT_ATLAS_SIZE; ///< The default size(width, height) of text-atlas-block.
73 static const uint32_t MAX_TEXT_ATLAS_WIDTH; ///< The maximum width of text-atlas-block.
74 static const uint32_t MAX_TEXT_ATLAS_HEIGHT; ///< The maximum height of text-atlas-block.
75 static const Size MAX_TEXT_ATLAS_SIZE; ///< The maximum height of text-atlas-block.
77 static const uint16_t PADDING_TEXT_ATLAS_BLOCK; ///< Padding per edge. How much the block size (width, height) less than the text-atlas-block size (width, height).
78 static const Size MAX_SIZE_FIT_IN_ATLAS; ///< The maximum block's size fit into text-atlas-block.
80 static const uint32_t NUMBER_OF_POINTS_PER_ONE_UNIT_OF_POINT_SIZE; ///< Factor multiply point-size in toolkit.
83 * @brief Used to load an embedded item into the font client.
85 struct EmbeddedItemDescription
87 std::string url; ///< The url path of the image.
88 unsigned int width; ///< The width of the item.
89 unsigned int height; ///< The height of the item.
90 ColorBlendingMode colorblendingMode; ///< Whether the color of the image is multiplied by the color of the text.
95 * @brief Retrieve a handle to the FontClient instance.
97 * @return A handle to the FontClient
99 static FontClient Get();
102 * @brief Create a handle to the new FontClient instance.
104 * @param[in] horizontalDpi The horizontal resolution in DPI.
105 * @param[in] verticalDpi The vertical resolution in DPI.
106 * @return A handle to the FontClient
108 static FontClient New(uint32_t horizontalDpi, uint32_t verticalDpi);
111 * @brief Create an uninitialized TextAbstraction handle.
118 * This is non-virtual since derived Handle types must not contain data or virtual methods.
123 * @brief This copy constructor is required for (smart) pointer semantics.
125 * @param[in] handle A reference to the copied handle.
127 FontClient(const FontClient& handle);
130 * @brief This assignment operator is required for (smart) pointer semantics.
132 * @param [in] handle A reference to the copied handle.
133 * @return A reference to this.
135 FontClient& operator=(const FontClient& handle);
138 * @brief This move constructor is required for (smart) pointer semantics.
140 * @param[in] handle A reference to the moved handle.
142 FontClient(FontClient&& handle);
145 * @brief This move assignment operator is required for (smart) pointer semantics.
147 * @param [in] handle A reference to the moved handle.
148 * @return A reference to this.
150 FontClient& operator=(FontClient&& handle);
152 ////////////////////////////////////////
153 // Font management and validation.
154 ////////////////////////////////////////
157 * @brief Clear all caches in FontClient
163 * @brief Set the DPI of the target window.
165 * @note Multiple windows are not currently supported.
166 * @param[in] horizontalDpi The horizontal resolution in DPI.
167 * @param[in] verticalDpi The vertical resolution in DPI.
169 void SetDpi(unsigned int horizontalDpi, unsigned int verticalDpi);
172 * @brief Retrieves the DPI previously set to the target window.
174 * @note Multiple windows are not currently supported.
175 * @param[out] horizontalDpi The horizontal resolution in DPI.
176 * @param[out] verticalDpi The vertical resolution in DPI.
178 void GetDpi(unsigned int& horizontalDpi, unsigned int& verticalDpi);
181 * @brief Called by Dali to retrieve the default font size for the platform.
183 * This is an accessibility size, which is mapped to a UI Control specific point-size in stylesheets.
184 * For example if zero the smallest size, this could potentially map to TextLabel point-size 8.
185 * @return The default font size.
187 int GetDefaultFontSize();
190 * @brief Called when the user changes the system defaults.
192 * @post Previously cached system defaults are removed.
194 void ResetSystemDefaults();
197 * @brief Retrieve the list of default fonts supported by the system.
199 * @param[out] defaultFonts A list of default font paths, family, width, weight and slant.
201 void GetDefaultFonts(FontList& defaultFonts);
204 * @brief Retrieve the active default font from the system.
206 * @param[out] fontDescription font structure describing the default font.
208 void GetDefaultPlatformFontDescription(FontDescription& fontDescription);
211 * @brief Retrieve the list of fonts supported by the system.
213 * @param[out] systemFonts A list of font paths, family, width, weight and slant.
215 void GetSystemFonts(FontList& systemFonts);
218 * @brief Retrieves the font description of a given font @p fontId.
220 * @param[in] fontId The font identifier.
221 * @param[out] fontDescription The path, family & style (width, weight and slant) describing the font.
223 void GetDescription(FontId fontId, FontDescription& fontDescription);
226 * @brief Retrieves the font point size of a given font @p fontId.
228 * @param[in] fontId The font identifier.
230 * @return The point size in 26.6 fractional points.
232 PointSize26Dot6 GetPointSize(FontId fontId);
235 * @brief Whether the given @p character is supported by the font.
237 * @param[in] fontId The id of the font.
238 * @param[in] character The character.
240 * @return @e true if the character is supported by the font.
242 bool IsCharacterSupportedByFont(FontId fontId, Character character);
245 * @brief Find the default font for displaying a UTF-32 character.
247 * This is useful when localised strings are provided for multiple languages
248 * i.e. when a single default font does not work for all languages.
250 * @param[in] charcode The character for which a font is needed.
251 * @param[in] requestedPointSize The point size in 26.6 fractional points; the default point size is 12*64.
252 * @param[in] preferColor @e true if a color font is preferred.
254 * @return A valid font identifier, or zero if the font does not exist.
256 FontId FindDefaultFont(Character charcode,
257 PointSize26Dot6 requestedPointSize = DEFAULT_POINT_SIZE,
258 bool preferColor = false);
261 * @brief Find a fallback-font for displaying a UTF-32 character.
263 * This is useful when localised strings are provided for multiple languages
264 * i.e. when a single default font does not work for all languages.
266 * @param[in] charcode The character for which a font is needed.
267 * @param[in] preferredFontDescription Description of the preferred font which may not provide a glyph for @p charcode.
268 * The fallback-font will be the closest match to @p preferredFontDescription, which does support the required glyph.
269 * @param[in] requestedPointSize The point size in 26.6 fractional points; the default point size is 12*64.
270 * @param[in] preferColor @e true if a color font is preferred.
272 * @return A valid font identifier, or zero if the font does not exist.
274 FontId FindFallbackFont(Character charcode,
275 const FontDescription& preferredFontDescription,
276 PointSize26Dot6 requestedPointSize = DEFAULT_POINT_SIZE,
277 bool preferColor = false);
280 * @brief Retrieve the unique identifier for a font.
282 * @param[in] path The path to a font file.
283 * @param[in] requestedPointSize The point size in 26.6 fractional points; the default point size is 12*64.
284 * @param[in] faceIndex The index of the font face (optional).
286 * @return A valid font identifier, or zero if the font does not exist.
288 FontId GetFontId(const FontPath& path,
289 PointSize26Dot6 requestedPointSize = DEFAULT_POINT_SIZE,
290 FaceIndex faceIndex = 0);
293 * @brief Retrieves a unique font identifier for a given description.
295 * @param[in] preferredFontDescription Description of the preferred font.
296 * The font will be the closest match to @p preferredFontDescription.
297 * @param[in] requestedPointSize The point size in 26.6 fractional points; the default point size is 12*64.
298 * @param[in] faceIndex The index of the font face (optional).
300 * @return A valid font identifier, or zero if no font is found.
302 FontId GetFontId(const FontDescription& preferredFontDescription,
303 PointSize26Dot6 requestedPointSize = DEFAULT_POINT_SIZE,
304 FaceIndex faceIndex = 0);
307 * @brief Retrieves a unique font identifier for a given bitmap font.
308 * If the font is not present, it will cache the given font, and give it a new font id.
310 * @param[in] bitmapFont A bitmap font.
312 * @return A valid font identifier.
314 FontId GetFontId(const BitmapFont& bitmapFont);
317 * @brief Check to see if a font is scalable.
319 * @param[in] path The path to a font file.
320 * @return true if scalable.
322 bool IsScalable(const FontPath& path);
325 * @brief Check to see if a font is scalable.
327 * @note It the font style is not empty, it will be used instead the font weight and font slant slant.
329 * @param[in] fontDescription A font description.
331 * @return true if scalable
333 bool IsScalable(const FontDescription& fontDescription);
336 * @brief Get a list of sizes available for a fixed size font.
338 * @param[in] path The path to a font file.
339 * @param[out] sizes A list of the available sizes, if no sizes available will return empty.
341 void GetFixedSizes(const FontPath& path, Dali::Vector<PointSize26Dot6>& sizes);
344 * @brief Get a list of sizes available for a fixed size font.
346 * @note It the font style is not empty, it will be used instead the font weight and font slant slant.
348 * @param[in] fontDescription A font description.
349 * @param[out] sizes A list of the available sizes, if no sizes available will return empty.
351 void GetFixedSizes(const FontDescription& fontDescription,
352 Dali::Vector<PointSize26Dot6>& sizes);
355 * @brief Whether the font has Italic style.
357 * @param[in] fontId The font identifier.
359 * @return true if the font has italic style.
361 bool HasItalicStyle(FontId fontId) const;
363 ////////////////////////////////////////
364 // Font metrics, glyphs and bitmaps.
365 ////////////////////////////////////////
368 * @brief Query the metrics for a font.
370 * @param[in] fontId The identifier of the font for the required glyph.
371 * @param[out] metrics The font metrics.
373 void GetFontMetrics(FontId fontId, FontMetrics& metrics);
376 * @brief Retrieve the glyph index for a UTF-32 character code.
378 * @param[in] fontId The identifier of the font for the required glyph.
379 * @param[in] charcode The UTF-32 character code.
381 * @return The glyph index, or zero if the character code is undefined.
383 GlyphIndex GetGlyphIndex(FontId fontId, Character charcode);
386 * @brief Return the glyph index of a given character code as modified by the variation selector.
388 * @param[in] fontId The identifier of the font for the required glyph.
389 * @param[in] charcode The UTF-32 character code.
390 * @param[in] variantSelector The UTF-32 character code point of the variation selector.
392 * @return The glyph index, or zero if the character code is undefined.
394 GlyphIndex GetGlyphIndex(FontId fontId, Character charcode, Character variantSelector);
397 * @brief Retrieve the metrics for a series of glyphs.
399 * @param[in,out] array An array of glyph-info structures with initialized FontId & GlyphIndex values.
400 * It may contain the advance and an offset set into the bearing from the shaping tool.
401 * On return, the glyph's size value will be initialized. The bearing value will be updated by adding the font's glyph bearing to the one set by the shaping tool.
402 * @param[in] size The size of the array.
403 * @param[in] type The type of glyphs used for rendering; either bitmaps or vectors.
404 * @param[in] horizontal True for horizontal layouts (set to false for vertical layouting).
406 * @return @e true if all of the requested metrics were found.
408 bool GetGlyphMetrics(GlyphInfo* array, uint32_t size, GlyphType type, bool horizontal = true);
411 * @brief Create a bitmap representation of a glyph.
413 * @note The caller is responsible for deallocating the bitmap data @p data.buffer using delete[].
415 * @param[in] fontId The identifier of the font.
416 * @param[in] glyphIndex The index of a glyph within the specified font.
417 * @param[in] isItalicRequired Whether the glyph requires italic style.
418 * @param[in] isBoldRequired Whether the glyph requires bold style.
419 * @param[out] data The bitmap data.
420 * @param[in] outlineWidth The width of the glyph outline in pixels.
422 void CreateBitmap(FontId fontId, GlyphIndex glyphIndex, bool isItalicRequired, bool isBoldRequired, GlyphBufferData& data, int outlineWidth);
425 * @brief Create a bitmap representation of a glyph.
427 * @param[in] fontId The identifier of the font.
428 * @param[in] glyphIndex The index of a glyph within the specified font.
429 * @param[in] outlineWidth The width of the glyph outline in pixels.
431 * @return A valid PixelData, or an empty handle if the glyph could not be rendered.
433 PixelData CreateBitmap(FontId fontId, GlyphIndex glyphIndex, int outlineWidth);
436 * @brief Create a vector representation of a glyph.
438 * @note This feature requires highp shader support and is not available on all platforms
439 * @param[in] fontId The identifier of the font.
440 * @param[in] glyphIndex The index of a glyph within the specified font.
441 * @param[out] blob A blob of data; this is owned by FontClient and should be copied by the caller of CreateVectorData().
442 * @param[out] blobLength The length of the blob data, or zero if the blob creation failed.
443 * @param[out] nominalWidth The width of the blob.
444 * @param[out] nominalHeight The height of the blob.
446 void CreateVectorBlob(FontId fontId,
447 GlyphIndex glyphIndex,
449 unsigned int& blobLength,
450 unsigned int& nominalWidth,
451 unsigned int& nominalHeight);
454 * @brief Retrieves the ellipsis glyph for a requested point size.
456 * @param[in] requestedPointSize The requested point size.
458 * @return The ellipsis glyph.
460 const GlyphInfo& GetEllipsisGlyph(PointSize26Dot6 requestedPointSize);
463 * @brief Whether the given glyph @p glyphIndex is a color glyph.
465 * @param[in] fontId The font id.
466 * @param[in] glyphIndex The glyph index.
468 * @return @e true if the glyph is a color one.
470 bool IsColorGlyph(FontId fontId, GlyphIndex glyphIndex);
473 * @brief Add custom fonts directory
475 * @param[in] path to the fonts directory
477 * @return true if the fonts can be added.
479 bool AddCustomFontDirectory(const FontPath& path);
482 * @brief Creates and stores an embedded item and it's metrics.
484 * If in the @p description there is a non empty url, it calls Dali::LoadImageFromFile() internally.
485 * If in the @p description there is a url and @e width or @e height are zero it stores the default size. Otherwise the image is resized.
486 * If the url in the @p description is empty it stores the size.
488 * @param[in] description The description of the embedded item.
489 * @param[out] pixelFormat The pixel format of the image.
491 * return The index within the vector of embedded items.
493 GlyphIndex CreateEmbeddedItem(const EmbeddedItemDescription& description, Pixel::Format& pixelFormat);
496 * @brief true to enable Atlas-Limitation.
498 * @note Used default configuration.
499 * @param[in] enabled The on/off value to enable/disable Atlas-Limitation.
501 void EnableAtlasLimitation(bool enabled);
504 * @brief Check Atlas-Limitation is enabled or disabled.
506 * @note Used default configuration.
507 * return true if Atlas-Limitation is enabled, otherwise false.
509 bool IsAtlasLimitationEnabled() const;
512 * @brief retrieve the maximum allowed width and height for text-atlas-block.
514 * @note Used default configuration.
515 * return the maximum width and height of text-atlas-block.
517 Size GetMaximumTextAtlasSize() const;
520 * @brief retrieve the default width and height for text-atlas-block.
522 * @note Used default configuration.
523 * return the default width and height of text-atlas-block.
525 Size GetDefaultTextAtlasSize() const;
528 * @brief retrieve the current maximum width and height for text-atlas-block.
530 * @note Used default configuration.
531 * return the current maximum width and height of text-atlas-block.
533 Size GetCurrentMaximumBlockSizeFitInAtlas() const;
536 * @brief set the achieved size (width and height) for text-atlas-block.
537 * If @p currentMaximumBlockSizeFitInAtlas larger than the current maximum text atlas then store, otherwise ignore.
539 * @note Used default configuration.
540 * return true if the current maximum text atlas size is changed, otherwise false.
542 bool SetCurrentMaximumBlockSizeFitInAtlas(const Size& currentMaximumBlockSizeFitInAtlas);
545 * @brief retrieve the number of points to scale-up one unit of point-size.
547 * @note Used default configuration.
548 * return the number of points per one unit of point-size
550 uint32_t GetNumberOfPointsPerOneUnitOfPointSize() const;
552 public: // Not intended for application developers
554 * @brief This constructor is used by FontClient::Get().
556 * @param[in] fontClient A pointer to the internal fontClient object.
558 explicit DALI_INTERNAL FontClient(Internal::FontClient* fontClient);
562 * @brief This is used to improve application launch performance
564 * @return A pre-initialized FontClient
566 DALI_ADAPTOR_API FontClient FontClientPreInitialize();
569 * @brief This is used to pre-cache fonts in order to improve the runtime performance of the application.
571 * @param[in] fallbackFamilyList A list of fallback font families to be pre-cached.
572 * @param[in] extraFamilyList A list of additional font families to be pre-cached.
573 * @param[in] localeFamily A locale font family to be pre-cached.
574 * @param[in] useThread True if the font client should create thread and perform pre-caching, false otherwise.
576 DALI_ADAPTOR_API void FontClientPreCache(const FontFamilyList& fallbackFamilyList, const FontFamilyList& extraFamilyList, const FontFamily& localeFamily, bool useThread);
578 } // namespace TextAbstraction
582 #endif // DALI_PLATFORM_TEXT_ABSTRACTION_FONT_CLIENT_H