LayerCache.h revision f607bdc167f66b3e7003acaa4736ae46d78c1492
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_LAYER_CACHE_H 18#define ANDROID_UI_LAYER_CACHE_H 19 20#include "Layer.h" 21#include "GenerationCache.h" 22 23namespace android { 24namespace uirenderer { 25 26/////////////////////////////////////////////////////////////////////////////// 27// Defines 28/////////////////////////////////////////////////////////////////////////////// 29 30// Debug 31#define DEBUG_LAYERS 0 32 33// Debug 34#if DEBUG_LAYERS 35 #define LAYER_LOGD(...) LOGD(__VA_ARGS__) 36#else 37 #define LAYER_LOGD(...) 38#endif 39 40/////////////////////////////////////////////////////////////////////////////// 41// Cache 42/////////////////////////////////////////////////////////////////////////////// 43 44class LayerCache: public OnEntryRemoved<LayerSize, Layer*> { 45public: 46 LayerCache(); 47 LayerCache(uint32_t maxByteSize); 48 ~LayerCache(); 49 50 /** 51 * Used as a callback when an entry is removed from the cache. 52 * Do not invoke directly. 53 */ 54 void operator()(LayerSize& size, Layer*& layer); 55 56 /** 57 * Returns the layer of specified dimensions. If not suitable layer 58 * can be found, a new one is created and returned. If creating a new 59 * layer fails, NULL is returned. 60 * 61 * When a layer is obtained from the cache, it is removed and the total 62 * size of the cache goes down. 63 * 64 * @param size The dimensions of the desired layer 65 */ 66 Layer* get(LayerSize& size); 67 /** 68 * Adds the layer to the cache. The layer will not be added if there is 69 * not enough space available. 70 * 71 * @param size The dimensions of the layer 72 * @param layer The layer to add to the cache 73 * 74 * @return True if the layer was added, false otherwise. 75 */ 76 bool put(LayerSize& size, Layer* layer); 77 /** 78 * Clears the cache. This causes all layers to be deleted. 79 */ 80 void clear(); 81 82 /** 83 * Sets the maximum size of the cache in bytes. 84 */ 85 void setMaxSize(uint32_t maxSize); 86 /** 87 * Returns the maximum size of the cache in bytes. 88 */ 89 uint32_t getMaxSize(); 90 /** 91 * Returns the current size of the cache in bytes. 92 */ 93 uint32_t getSize(); 94 95private: 96 void deleteLayer(Layer* layer); 97 98 GenerationCache<LayerSize, Layer*> mCache; 99 uint32_t mIdGenerator; 100 101 uint32_t mSize; 102 uint32_t mMaxSize; 103}; // class LayerCache 104 105}; // namespace uirenderer 106}; // namespace android 107 108#endif // ANDROID_UI_LAYER_CACHE_H 109