LayerCache.cpp revision 8550c4c7b5952b7a4e1e0ede95c9492d03099a13 
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#define LOG_TAG "OpenGLRenderer"
18
19#include <GLES2/gl2.h>
20
21#include <utils/Log.h>
22
23#include "LayerCache.h"
24#include "Properties.h"
25
26namespace android {
27namespace uirenderer {
28
29///////////////////////////////////////////////////////////////////////////////
30// Constructors/destructor
31///////////////////////////////////////////////////////////////////////////////
32
33LayerCache::LayerCache(): mSize(0), mMaxSize(MB(DEFAULT_LAYER_CACHE_SIZE)) {
34    char property[PROPERTY_VALUE_MAX];
35    if (property_get(PROPERTY_LAYER_CACHE_SIZE, property, NULL) > 0) {
36        LOGD("  Setting layer cache size to %sMB", property);
37        setMaxSize(MB(atof(property)));
38    } else {
39        LOGD("  Using default layer cache size of %.2fMB", DEFAULT_LAYER_CACHE_SIZE);
40    }
41}
42
43LayerCache::~LayerCache() {
44    clear();
45}
46
47///////////////////////////////////////////////////////////////////////////////
48// Size management
49///////////////////////////////////////////////////////////////////////////////
50
51uint32_t LayerCache::getSize() {
52    return mSize;
53}
54
55uint32_t LayerCache::getMaxSize() {
56    return mMaxSize;
57}
58
59void LayerCache::setMaxSize(uint32_t maxSize) {
60    clear();
61    mMaxSize = maxSize;
62}
63
64///////////////////////////////////////////////////////////////////////////////
65// Caching
66///////////////////////////////////////////////////////////////////////////////
67
68void LayerCache::deleteLayer(Layer* layer) {
69    if (layer) {
70        mSize -= layer->width * layer->height * 4;
71
72        glDeleteTextures(1, &layer->texture);
73        delete layer;
74    }
75}
76
77void LayerCache::clear() {
78    size_t count = mCache.size();
79    for (size_t i = 0; i < count; i++) {
80        deleteLayer(mCache.itemAt(i).mLayer);
81    }
82    mCache.clear();
83}
84
85Layer* LayerCache::get(const uint32_t width, const uint32_t height) {
86    Layer* layer = NULL;
87
88    LayerEntry entry(width, height);
89    ssize_t index = mCache.indexOf(entry);
90
91    if (index >= 0) {
92        entry = mCache.itemAt(index);
93        mCache.removeAt(index);
94
95        layer = entry.mLayer;
96        mSize -= layer->width * layer->height * 4;
97
98        LAYER_LOGD("Reusing layer %dx%d", layer->width, layer->height);
99    } else {
100        LAYER_LOGD("Creating new layer %dx%d", entry.mWidth, entry.mHeight);
101
102        layer = new Layer(entry.mWidth, entry.mHeight);
103        layer->blend = true;
104        layer->empty = true;
105        layer->fbo = 0;
106
107        glGenTextures(1, &layer->texture);
108        glBindTexture(GL_TEXTURE_2D, layer->texture);
109
110        glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
111
112        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
113        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
114
115        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
116        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
117
118#if DEBUG_LAYERS
119        size_t size = mCache.size();
120        for (size_t i = 0; i < size; i++) {
121            const LayerEntry& entry = mCache.itemAt(i);
122            LAYER_LOGD("  Layer size %dx%d", entry.mWidth, entry.mHeight);
123        }
124#endif
125    }
126
127    return layer;
128}
129
130bool LayerCache::put(Layer* layer) {
131    const uint32_t size = layer->width * layer->height * 4;
132    // Don't even try to cache a layer that's bigger than the cache
133    if (size < mMaxSize) {
134        // TODO: Use an LRU
135        while (mSize + size > mMaxSize) {
136            Layer* biggest = mCache.top().mLayer;
137            deleteLayer(biggest);
138            mCache.removeAt(mCache.size() - 1);
139
140            LAYER_LOGD("  Deleting layer %.2fx%.2f", biggest->layer.getWidth(),
141                    biggest->layer.getHeight());
142        }
143
144        LayerEntry entry(layer);
145
146        mCache.add(entry);
147        mSize += size;
148
149        return true;
150    }
151    return false;
152}
153
154}; // namespace uirenderer
155}; // namespace android
156