Glyph cache renders different characters on a texture with the font and font size that you use in your Kanzi application. More...
#include <kanzi/core.ui/font/glyph_cache.hpp>
Classes | |
| struct | TextureCoordinates |
| Coordinates to the position of a single glyph in a glyph cache texture. More... | |
Public Member Functions | |
| void | clear () |
| Removes all stored glyphs from the glyph cache. | |
| size_t | getGeneration () const |
| Returns the current generation of the glyph cache, which is incremented whenever the texture coordinates of any glyph are invalidated. | |
| TextureSharedPtr | getTexture () const |
| Returns the texture that the glyph cache uses. | |
| GlyphCache (TextureSharedPtr texture, FontFileSharedPtr font, float glyphSize) | |
| Constructor. | |
| void | remove (const GlyphKey &glyphKey) |
| Removes a stored glyph from the glyph cache. | |
| size_t | retrieveMultipleTextureCoordinates (const GlyphKey *glyphKeys, size_t glyphCount, size_t stride, size_t recycleGeneration, byte *outData) |
| Gets the texture coordinates for multiple glyphs. | |
| size_t | retrieveMultipleTextureCoordinatesWithClipping (const GlyphKey *glyphKeys, size_t glyphCount, size_t stride, const float *clippingCoordinates, size_t recycleGeneration, byte *outData) |
| Gets the texture coordinates for multiple glyphs that can be partially clipped. | |
| TextureCoordinates | retrieveTextureCoordinates (const GlyphKey &glyphKey) |
| Gets the texture coordinates for the given glyph. | |
| TextureCoordinates | retrieveTextureCoordinatesRecycling (const GlyphKey &glyphKey, size_t recycleGeneration) |
| Gets the texture coordinates for the given glyph. | |
| ~GlyphCache () | |
| Destructor. | |
Glyph cache renders different characters on a texture with the font and font size that you use in your Kanzi application.
The default size is 512 by 512 pixels. The upper size limit depends on the GPU, but is usually 2048 by 2048 pixels. To ensure optimal performance of your Kanzi application, adjust the size of the glyph cache so that the size of the glyph cache is large enough to fit all the glyphs that your Kanzi application uses. However, keep in mind that larger glyph cache consumes more memory.
If the glyph cache becomes full, Kanzi removes from the texture the least used glyphs to make room for the new glyphs. This decreases Kanzi application performance. To avoid a decrease in the performance, adjust the size of the glyph cache so that all glyphs fit into the glyph cache. You can fit more glyphs into the glyph cache by using smaller font sizes.
You can adjust the size of glyph cache textures using these application configuration properties:
You can retrieve the coordinates of the glyphs from a glyph cache. If Kanzi already rendered a certain glyph, when you retrieve the coordinates of that glyph, that does not trigger new rendering of that glyph. Kanzi creates a glyph cache for every font and font size combination.
To learn more about the glyph cache, in Kanzi documentation see Working with > Application configuration > Application configuration reference > Glyph cache texture size
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explicit |
Constructor.
| texture | Pointer to the texture that the glyph cache uses. Must be in the format GraphicsFormatLUMINANCE8_ALPHA8_UNORM. |
| font | Pointer to the font that the glyph cache uses. |
| glyphSize | Size of the font in pixels that the glyph cache uses. |
| kanzi::GlyphCache::~GlyphCache | ( | ) |
Destructor.
| void kanzi::GlyphCache::clear | ( | ) |
Removes all stored glyphs from the glyph cache.
Removes a stored glyph from the glyph cache.
| glyphKey | GlyphKey of the glyph in the used font. |
| TextureCoordinates kanzi::GlyphCache::retrieveTextureCoordinates | ( | const GlyphKey & | glyphKey | ) |
Gets the texture coordinates for the given glyph.
If the glyph is not in the glyph cache texture, Kanzi renders it to that textures using the font that Kanzi used to create the glyph cache. If there is no room in the glyph cache for a new glyph, the texture coordinates are zero and TextureCoordinates::success is false.
| glyphKey | GlyphKey of the glyph in the used font. |
| TextureCoordinates kanzi::GlyphCache::retrieveTextureCoordinatesRecycling | ( | const GlyphKey & | glyphKey, |
| size_t | recycleGeneration ) |
Gets the texture coordinates for the given glyph.
If the glyph is not in the glyph cache texture, Kanzi renders it to that texture using the font that Kanzi used to create the glyph cache. If there is no room left in the glyph cache for a new glyph, Kanzi replaces the least used glyphs with the new glyph.
| glyphKey | GlyphKey of the glyph in the used font. |
| recycleGeneration | Recycle generation counter. |
| size_t kanzi::GlyphCache::retrieveMultipleTextureCoordinates | ( | const GlyphKey * | glyphKeys, |
| size_t | glyphCount, | ||
| size_t | stride, | ||
| size_t | recycleGeneration, | ||
| byte * | outData ) |
Gets the texture coordinates for multiple glyphs.
If a glyph is not in the glyph cache texture, Kanzi renders it to that texture using the font that Kanzi used to create the glyph cache. Kanzi writes the 12 texture coordinates of a glyph to the output parameter outData. If there is no room left in the glyph cache for a new glyph, Kanzi does not write that and the following glyphs.
| glyphKeys | Pointer to the array containing multiple glyph keys. See GlyphKey, |
| glyphCount | Number of glyph indices in the array. |
| stride | Stride for the output array. Must be at least 2*sizeof(float). |
| recycleGeneration | Recycle generation counter. |
| outData | Pointer to the byte array for the output data. For each glyph must have at least 2*6*sizeof(float) space. |
| size_t kanzi::GlyphCache::retrieveMultipleTextureCoordinatesWithClipping | ( | const GlyphKey * | glyphKeys, |
| size_t | glyphCount, | ||
| size_t | stride, | ||
| const float * | clippingCoordinates, | ||
| size_t | recycleGeneration, | ||
| byte * | outData ) |
Gets the texture coordinates for multiple glyphs that can be partially clipped.
| glyphKeys | Pointer to the array containing multiple glyph keys. See GlyphKey, |
| glyphCount | Number of glyph indices in the array. |
| stride | Stride for the output array. Must be at least 2*sizeof(float). |
| clippingCoordinates | Pointer to the array with clipping coordinates for the glyphs. Amount of clipping as fraction of glyph size, from the clipped edge. For each glyph: left, right, bottom, and top. |
| recycleGeneration | Recycle generation counter. |
| outData | Pointer to the byte array for the output data. For each glyph must have at least 2*6*sizeof(float) space. |
| TextureSharedPtr kanzi::GlyphCache::getTexture | ( | ) | const |
Returns the texture that the glyph cache uses.
|
inline |
Returns the current generation of the glyph cache, which is incremented whenever the texture coordinates of any glyph are invalidated.