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      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_HWUI_TEXTURE_CACHE_H
     18 #define ANDROID_HWUI_TEXTURE_CACHE_H
     19 
     20 #include <SkBitmap.h>
     21 
     22 #include <utils/Vector.h>
     23 
     24 #include "Debug.h"
     25 #include "Texture.h"
     26 #include "utils/GenerationCache.h"
     27 
     28 namespace android {
     29 namespace uirenderer {
     30 
     31 ///////////////////////////////////////////////////////////////////////////////
     32 // Defines
     33 ///////////////////////////////////////////////////////////////////////////////
     34 
     35 // Debug
     36 #if DEBUG_TEXTURES
     37     #define TEXTURE_LOGD(...) LOGD(__VA_ARGS__)
     38 #else
     39     #define TEXTURE_LOGD(...)
     40 #endif
     41 
     42 ///////////////////////////////////////////////////////////////////////////////
     43 // Classes
     44 ///////////////////////////////////////////////////////////////////////////////
     45 
     46 /**
     47  * A simple LRU texture cache. The cache has a maximum size expressed in bytes.
     48  * Any texture added to the cache causing the cache to grow beyond the maximum
     49  * allowed size will also cause the oldest texture to be kicked out.
     50  */
     51 class TextureCache: public OnEntryRemoved<SkBitmap*, Texture*> {
     52 public:
     53     TextureCache();
     54     TextureCache(uint32_t maxByteSize);
     55     ~TextureCache();
     56 
     57     /**
     58      * Used as a callback when an entry is removed from the cache.
     59      * Do not invoke directly.
     60      */
     61     void operator()(SkBitmap*& bitmap, Texture*& texture);
     62 
     63     /**
     64      * Returns the texture associated with the specified bitmap. If the texture
     65      * cannot be found in the cache, a new texture is generated.
     66      */
     67     Texture* get(SkBitmap* bitmap);
     68     /**
     69      * Removes the texture associated with the specified bitmap.
     70      * Upon remove the texture is freed.
     71      */
     72     void remove(SkBitmap* bitmap);
     73     /**
     74      * Removes the texture associated with the specified bitmap. This is meant
     75      * to be called from threads that are not the EGL context thread.
     76      */
     77     void removeDeferred(SkBitmap* bitmap);
     78     /**
     79      * Process deferred removals.
     80      */
     81     void clearGarbage();
     82 
     83     /**
     84      * Clears the cache. This causes all textures to be deleted.
     85      */
     86     void clear();
     87 
     88     /**
     89      * Sets the maximum size of the cache in bytes.
     90      */
     91     void setMaxSize(uint32_t maxSize);
     92     /**
     93      * Returns the maximum size of the cache in bytes.
     94      */
     95     uint32_t getMaxSize();
     96     /**
     97      * Returns the current size of the cache in bytes.
     98      */
     99     uint32_t getSize();
    100 
    101 private:
    102     /**
    103      * Generates the texture from a bitmap into the specified texture structure.
    104      *
    105      * @param regenerate If true, the bitmap data is reuploaded into the texture, but
    106      *        no new texture is generated.
    107      */
    108     void generateTexture(SkBitmap* bitmap, Texture* texture, bool regenerate = false);
    109 
    110     void uploadLoFiTexture(bool resize, SkBitmap* bitmap, uint32_t width, uint32_t height);
    111     void uploadToTexture(bool resize, GLenum format, GLsizei width, GLsizei height,
    112             GLenum type, const GLvoid * data);
    113 
    114     void init();
    115 
    116     GenerationCache<SkBitmap*, Texture*> mCache;
    117 
    118     uint32_t mSize;
    119     uint32_t mMaxSize;
    120     GLint mMaxTextureSize;
    121 
    122     bool mDebugEnabled;
    123 
    124     Vector<SkBitmap*> mGarbage;
    125     mutable Mutex mLock;
    126 }; // class TextureCache
    127 
    128 }; // namespace uirenderer
    129 }; // namespace android
    130 
    131 #endif // ANDROID_HWUI_TEXTURE_CACHE_H
    132