TextureCache.h revision 5f0c6a483900f3989f4d2a8f913cf5b6a9777d03
1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ANDROID_UI_TEXTURE_CACHE_H 18#define ANDROID_UI_TEXTURE_CACHE_H 19 20#include <SkBitmap.h> 21 22#include "Texture.h" 23#include "GenerationCache.h" 24 25namespace android { 26namespace uirenderer { 27 28/** 29 * A simple LRU texture cache. The cache has a maximum size expressed in bytes. 30 * Any texture added to the cache causing the cache to grow beyond the maximum 31 * allowed size will also cause the oldest texture to be kicked out. 32 */ 33class TextureCache: public OnEntryRemoved<SkBitmap*, Texture*> { 34public: 35 TextureCache(uint32_t maxByteSize); 36 ~TextureCache(); 37 38 /** 39 * Used as a callback when an entry is removed from the cache. 40 * Do not invoke directly. 41 */ 42 void operator()(SkBitmap*& bitmap, Texture*& texture); 43 44 /** 45 * Returns the texture associated with the specified bitmap. If the texture 46 * cannot be found in the cache, a new texture is generated. 47 */ 48 Texture* get(SkBitmap* bitmap); 49 /** 50 * Removes the texture associated with the specified bitmap. Returns NULL 51 * if the texture cannot be found. Upon remove the texture is freed. 52 */ 53 void remove(SkBitmap* bitmap); 54 /** 55 * Clears the cache. This causes all textures to be deleted. 56 */ 57 void clear(); 58 59 /** 60 * Sets the maximum size of the cache in bytes. 61 */ 62 void setMaxSize(uint32_t maxSize); 63 /** 64 * Returns the maximum size of the cache in bytes. 65 */ 66 uint32_t getMaxSize(); 67 /** 68 * Returns the current size of the cache in bytes. 69 */ 70 uint32_t getSize(); 71 72private: 73 /** 74 * Generates the texture from a bitmap into the specified texture structure. 75 * 76 * @param regenerate If true, the bitmap data is reuploaded into the texture, but 77 * no new texture is generated. 78 */ 79 void generateTexture(SkBitmap* bitmap, Texture* texture, bool regenerate = false); 80 81 GenerationSingleCache<SkBitmap*, Texture*> mCache; 82 83 uint32_t mSize; 84 uint32_t mMaxSize; 85}; // class TextureCache 86 87}; // namespace uirenderer 88}; // namespace android 89 90#endif // ANDROID_UI_TEXTURE_CACHE_H 91