GradientCache.cpp revision eb61cd8296ed7e3f3aef5bd430d846aa54d5d7e2 
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 <SkCanvas.h>
22#include <SkGradientShader.h>
23
24#include <utils/threads.h>
25
26#include "Debug.h"
27#include "GradientCache.h"
28#include "Properties.h"
29
30namespace android {
31namespace uirenderer {
32
33///////////////////////////////////////////////////////////////////////////////
34// Constructors/destructor
35///////////////////////////////////////////////////////////////////////////////
36
37GradientCache::GradientCache():
38        mCache(GenerationCache<GradientCacheEntry, Texture*>::kUnlimitedCapacity),
39        mSize(0), mMaxSize(MB(DEFAULT_GRADIENT_CACHE_SIZE)) {
40    char property[PROPERTY_VALUE_MAX];
41    if (property_get(PROPERTY_GRADIENT_CACHE_SIZE, property, NULL) > 0) {
42        INIT_LOGD("  Setting gradient cache size to %sMB", property);
43        setMaxSize(MB(atof(property)));
44    } else {
45        INIT_LOGD("  Using default gradient cache size of %.2fMB", DEFAULT_GRADIENT_CACHE_SIZE);
46    }
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    SkBitmap bitmap;
120    bitmap.setConfig(SkBitmap::kARGB_8888_Config, 256 * (count - 1), 1);
121    bitmap.allocPixels();
122    bitmap.eraseColor(0);
123
124    SkCanvas canvas(bitmap);
125
126    SkPoint points[2];
127    points[0].set(0.0f, 0.0f);
128    points[1].set(bitmap.width(), 0.0f);
129
130    SkShader* localShader = SkGradientShader::CreateLinear(points,
131            reinterpret_cast<const SkColor*>(colors), positions, count, tileMode);
132
133    SkPaint p;
134    p.setStyle(SkPaint::kStrokeAndFill_Style);
135    p.setShader(localShader)->unref();
136
137    canvas.drawRectCoords(0.0f, 0.0f, bitmap.width(), 1.0f, p);
138
139    // Asume the cache is always big enough
140    const uint32_t size = bitmap.rowBytes() * bitmap.height();
141    while (mSize + size > mMaxSize) {
142        mCache.removeOldest();
143    }
144
145    Texture* texture = new Texture;
146    generateTexture(&bitmap, texture);
147
148    mSize += size;
149    mCache.put(gradient, texture);
150
151    return texture;
152}
153
154void GradientCache::generateTexture(SkBitmap* bitmap, Texture* texture) {
155    SkAutoLockPixels autoLock(*bitmap);
156    if (!bitmap->readyToDraw()) {
157        ALOGE("Cannot generate texture from shader");
158        return;
159    }
160
161    texture->generation = bitmap->getGenerationID();
162    texture->width = bitmap->width();
163    texture->height = bitmap->height();
164
165    glGenTextures(1, &texture->id);
166
167    glBindTexture(GL_TEXTURE_2D, texture->id);
168    glPixelStorei(GL_UNPACK_ALIGNMENT, bitmap->bytesPerPixel());
169
170    texture->blend = !bitmap->isOpaque();
171    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bitmap->rowBytesAsPixels(), texture->height, 0,
172            GL_RGBA, GL_UNSIGNED_BYTE, bitmap->getPixels());
173
174    texture->setFilter(GL_LINEAR);
175    texture->setWrap(GL_CLAMP_TO_EDGE);
176}
177
178}; // namespace uirenderer
179}; // namespace android
180