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/LruCache.h>
23 #include <utils/Mutex.h>
24 #include <utils/Vector.h>
25 
26 #include "Debug.h"
27 
28 namespace android {
29 namespace uirenderer {
30 
31 class Texture;
32 
33 ///////////////////////////////////////////////////////////////////////////////
34 // Defines
35 ///////////////////////////////////////////////////////////////////////////////
36 
37 // Debug
38 #if DEBUG_TEXTURES
39     #define TEXTURE_LOGD(...) ALOGD(__VA_ARGS__)
40 #else
41     #define TEXTURE_LOGD(...)
42 #endif
43 
44 ///////////////////////////////////////////////////////////////////////////////
45 // Classes
46 ///////////////////////////////////////////////////////////////////////////////
47 
48 class AssetAtlas;
49 
50 /**
51  * A simple LRU texture cache. The cache has a maximum size expressed in bytes.
52  * Any texture added to the cache causing the cache to grow beyond the maximum
53  * allowed size will also cause the oldest texture to be kicked out.
54  */
55 class TextureCache : public OnEntryRemoved<uint32_t, Texture*> {
56 public:
57     TextureCache();
58     ~TextureCache();
59 
60     /**
61      * Used as a callback when an entry is removed from the cache.
62      * Do not invoke directly.
63      */
64     void operator()(uint32_t&, Texture*& texture) override;
65 
66     /**
67      * Resets all Textures to not be marked as in use
68      */
69     void resetMarkInUse(void* ownerToken);
70 
71     /**
72      * Attempts to precache the SkBitmap. Returns true if a Texture was successfully
73      * acquired for the bitmap, false otherwise. If a Texture was acquired it is
74      * marked as in use.
75      */
76     bool prefetchAndMarkInUse(void* ownerToken, const SkBitmap* bitmap);
77 
78     /**
79      * Returns the texture associated with the specified bitmap from either within the cache, or
80      * the AssetAtlas. If the texture cannot be found in the cache, a new texture is generated.
81      */
get(const SkBitmap * bitmap)82     Texture* get(const SkBitmap* bitmap) {
83         return get(bitmap, AtlasUsageType::Use);
84     }
85 
86     /**
87      * Returns the texture associated with the specified bitmap. If the texture cannot be found in
88      * the cache, a new texture is generated, even if it resides in the AssetAtlas.
89      */
getAndBypassAtlas(const SkBitmap * bitmap)90     Texture* getAndBypassAtlas(const SkBitmap* bitmap) {
91         return get(bitmap, AtlasUsageType::Bypass);
92     }
93 
94     /**
95      * Removes the texture associated with the specified pixelRef. This is meant
96      * to be called from threads that are not the EGL context thread.
97      */
98     ANDROID_API void releaseTexture(uint32_t pixelRefStableID);
99     /**
100      * Process deferred removals.
101      */
102     void clearGarbage();
103 
104     /**
105      * Clears the cache. This causes all textures to be deleted.
106      */
107     void clear();
108 
109     /**
110      * Sets the maximum size of the cache in bytes.
111      */
112     void setMaxSize(uint32_t maxSize);
113     /**
114      * Returns the maximum size of the cache in bytes.
115      */
116     uint32_t getMaxSize();
117     /**
118      * Returns the current size of the cache in bytes.
119      */
120     uint32_t getSize();
121 
122     /**
123      * Partially flushes the cache. The amount of memory freed by a flush
124      * is defined by the flush rate.
125      */
126     void flush();
127     /**
128      * Indicates the percentage of the cache to retain when a
129      * memory trim is requested (see Caches::flush).
130      */
131     void setFlushRate(float flushRate);
132 
133     void setAssetAtlas(AssetAtlas* assetAtlas);
134 
135 private:
136     enum class AtlasUsageType {
137         Use,
138         Bypass,
139     };
140 
141     bool canMakeTextureFromBitmap(const SkBitmap* bitmap);
142 
143     Texture* get(const SkBitmap* bitmap, AtlasUsageType atlasUsageType);
144     Texture* getCachedTexture(const SkBitmap* bitmap, AtlasUsageType atlasUsageType);
145 
146     /**
147      * Generates the texture from a bitmap into the specified texture structure.
148      *
149      * @param regenerate If true, the bitmap data is reuploaded into the texture, but
150      *        no new texture is generated.
151      */
152     void generateTexture(const SkBitmap* bitmap, Texture* texture, bool regenerate = false);
153 
154     void uploadLoFiTexture(bool resize, const SkBitmap* bitmap, uint32_t width, uint32_t height);
155     void uploadToTexture(bool resize, GLenum format, GLsizei stride, GLsizei bpp,
156             GLsizei width, GLsizei height, GLenum type, const GLvoid * data);
157 
158     LruCache<uint32_t, Texture*> mCache;
159 
160     uint32_t mSize;
161     uint32_t mMaxSize;
162     GLint mMaxTextureSize;
163 
164     float mFlushRate;
165 
166     bool mDebugEnabled;
167 
168     Vector<uint32_t> mGarbage;
169     mutable Mutex mLock;
170 
171     AssetAtlas* mAssetAtlas;
172 }; // class TextureCache
173 
174 }; // namespace uirenderer
175 }; // namespace android
176 
177 #endif // ANDROID_HWUI_TEXTURE_CACHE_H
178