GradientCache.cpp revision 98ba89492a477114148fcb1f89675e41679ca7cc 
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 <SkCanvas.h>
20#include <SkGradientShader.h>
21
22#include <utils/threads.h>
23
24#include "Debug.h"
25#include "GradientCache.h"
26#include "Properties.h"
27
28namespace android {
29namespace uirenderer {
30
31///////////////////////////////////////////////////////////////////////////////
32// Constructors/destructor
33///////////////////////////////////////////////////////////////////////////////
34
35GradientCache::GradientCache():
36        mCache(GenerationCache<GradientCacheEntry, Texture*>::kUnlimitedCapacity),
37        mSize(0), mMaxSize(MB(DEFAULT_GRADIENT_CACHE_SIZE)) {
38    char property[PROPERTY_VALUE_MAX];
39    if (property_get(PROPERTY_GRADIENT_CACHE_SIZE, property, NULL) > 0) {
40        INIT_LOGD("  Setting gradient cache size to %sMB", property);
41        setMaxSize(MB(atof(property)));
42    } else {
43        INIT_LOGD("  Using default gradient cache size of %.2fMB", DEFAULT_GRADIENT_CACHE_SIZE);
44    }
45
46    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &mMaxTextureSize);
47
48    mCache.setOnEntryRemovedListener(this);
49}
50
51GradientCache::GradientCache(uint32_t maxByteSize):
52        mCache(GenerationCache<GradientCacheEntry, Texture*>::kUnlimitedCapacity),
53        mSize(0), mMaxSize(maxByteSize) {
54    mCache.setOnEntryRemovedListener(this);
55}
56
57GradientCache::~GradientCache() {
58    mCache.clear();
59}
60
61///////////////////////////////////////////////////////////////////////////////
62// Size management
63///////////////////////////////////////////////////////////////////////////////
64
65uint32_t GradientCache::getSize() {
66    return mSize;
67}
68
69uint32_t GradientCache::getMaxSize() {
70    return mMaxSize;
71}
72
73void GradientCache::setMaxSize(uint32_t maxSize) {
74    mMaxSize = maxSize;
75    while (mSize > mMaxSize) {
76        mCache.removeOldest();
77    }
78}
79
80///////////////////////////////////////////////////////////////////////////////
81// Callbacks
82///////////////////////////////////////////////////////////////////////////////
83
84void GradientCache::operator()(GradientCacheEntry& shader, Texture*& texture) {
85    if (texture) {
86        const uint32_t size = texture->width * texture->height * 4;
87        mSize -= size;
88    }
89
90    if (texture) {
91        glDeleteTextures(1, &texture->id);
92        delete texture;
93    }
94}
95
96///////////////////////////////////////////////////////////////////////////////
97// Caching
98///////////////////////////////////////////////////////////////////////////////
99
100Texture* GradientCache::get(uint32_t* colors, float* positions,
101        int count, SkShader::TileMode tileMode) {
102
103    GradientCacheEntry gradient(colors, positions, count, tileMode);
104    Texture* texture = mCache.get(gradient);
105
106    if (!texture) {
107        texture = addLinearGradient(gradient, colors, positions, count, tileMode);
108    }
109
110    return texture;
111}
112
113void GradientCache::clear() {
114    mCache.clear();
115}
116
117Texture* GradientCache::addLinearGradient(GradientCacheEntry& gradient,
118        uint32_t* colors, float* positions, int count, SkShader::TileMode tileMode) {
119    int width = 256 * (count - 1);
120    width = width < mMaxTextureSize ? width : mMaxTextureSize;
121
122    SkBitmap bitmap;
123    bitmap.setConfig(SkBitmap::kARGB_8888_Config, width, 4);
124    bitmap.allocPixels();
125    bitmap.eraseColor(0);
126
127    SkCanvas canvas(bitmap);
128
129    SkPoint points[2];
130    points[0].set(0.0f, 0.0f);
131    points[1].set(bitmap.width(), 0.0f);
132
133    SkShader* localShader = SkGradientShader::CreateLinear(points,
134            reinterpret_cast<const SkColor*>(colors), positions, count, tileMode);
135
136    SkPaint p;
137    p.setStyle(SkPaint::kStrokeAndFill_Style);
138    p.setShader(localShader)->unref();
139
140    canvas.drawRectCoords(0.0f, 0.0f, bitmap.width(), 4.0f, p);
141
142    // Asume the cache is always big enough
143    const uint32_t size = bitmap.rowBytes() * bitmap.height();
144    while (mSize + size > mMaxSize) {
145        mCache.removeOldest();
146    }
147
148    Texture* texture = new Texture;
149    generateTexture(&bitmap, texture);
150
151    mSize += size;
152    mCache.put(gradient, texture);
153
154    return texture;
155}
156
157void GradientCache::generateTexture(SkBitmap* bitmap, Texture* texture) {
158    SkAutoLockPixels autoLock(*bitmap);
159    if (!bitmap->readyToDraw()) {
160        ALOGE("Cannot generate texture from shader");
161        return;
162    }
163
164    texture->generation = bitmap->getGenerationID();
165    texture->width = bitmap->width();
166    texture->height = bitmap->height();
167
168    glGenTextures(1, &texture->id);
169
170    glBindTexture(GL_TEXTURE_2D, texture->id);
171    glPixelStorei(GL_UNPACK_ALIGNMENT, bitmap->bytesPerPixel());
172
173    texture->blend = !bitmap->isOpaque();
174    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bitmap->rowBytesAsPixels(), texture->height, 0,
175            GL_RGBA, GL_UNSIGNED_BYTE, bitmap->getPixels());
176
177    texture->setFilter(GL_LINEAR);
178    texture->setWrap(GL_CLAMP_TO_EDGE);
179}
180
181}; // namespace uirenderer
182}; // namespace android
183