PathCache.cpp revision 9e10841c27d973b930e1b49a099c69d866659505 
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 <SkRect.h>
23
24#include <utils/threads.h>
25
26#include "PathCache.h"
27#include "Properties.h"
28
29namespace android {
30namespace uirenderer {
31
32///////////////////////////////////////////////////////////////////////////////
33// Constructors/destructor
34///////////////////////////////////////////////////////////////////////////////
35
36PathCache::PathCache():
37        mCache(GenerationCache<PathCacheEntry, PathTexture*>::kUnlimitedCapacity),
38        mSize(0), mMaxSize(MB(DEFAULT_PATH_CACHE_SIZE)) {
39    char property[PROPERTY_VALUE_MAX];
40    if (property_get(PROPERTY_PATH_CACHE_SIZE, property, NULL) > 0) {
41        LOGD("  Setting path cache size to %sMB", property);
42        setMaxSize(MB(atof(property)));
43    } else {
44        LOGD("  Using default path cache size of %.2fMB", DEFAULT_PATH_CACHE_SIZE);
45    }
46    init();
47}
48
49PathCache::PathCache(uint32_t maxByteSize):
50        mCache(GenerationCache<PathCacheEntry, PathTexture*>::kUnlimitedCapacity),
51        mSize(0), mMaxSize(maxByteSize) {
52    init();
53}
54
55PathCache::~PathCache() {
56    Mutex::Autolock _l(mLock);
57    mCache.clear();
58}
59
60void PathCache::init() {
61    mCache.setOnEntryRemovedListener(this);
62
63    GLint maxTextureSize;
64    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTextureSize);
65    mMaxTextureSize = maxTextureSize;
66}
67
68///////////////////////////////////////////////////////////////////////////////
69// Size management
70///////////////////////////////////////////////////////////////////////////////
71
72uint32_t PathCache::getSize() {
73    Mutex::Autolock _l(mLock);
74    return mSize;
75}
76
77uint32_t PathCache::getMaxSize() {
78    Mutex::Autolock _l(mLock);
79    return mMaxSize;
80}
81
82void PathCache::setMaxSize(uint32_t maxSize) {
83    Mutex::Autolock _l(mLock);
84    mMaxSize = maxSize;
85    while (mSize > mMaxSize) {
86        mCache.removeOldest();
87    }
88}
89
90///////////////////////////////////////////////////////////////////////////////
91// Callbacks
92///////////////////////////////////////////////////////////////////////////////
93
94void PathCache::operator()(PathCacheEntry& path, PathTexture*& texture) {
95    if (texture) {
96        const uint32_t size = texture->width * texture->height;
97        mSize -= size;
98
99        PATH_LOGD("PathCache::callback: delete path: name, size, mSize = %d, %d, %d",
100                texture->id, size, mSize);
101
102        glDeleteTextures(1, &texture->id);
103        delete texture;
104    }
105}
106
107///////////////////////////////////////////////////////////////////////////////
108// Caching
109///////////////////////////////////////////////////////////////////////////////
110
111void PathCache::remove(SkPath* path) {
112    Mutex::Autolock _l(mLock);
113
114    // TODO: Linear search...
115    Vector<uint32_t> pathsToRemove;
116    for (uint32_t i = 0; i < mCache.size(); i++) {
117        if (mCache.getKeyAt(i).path == path) {
118            pathsToRemove.push(i);
119        }
120    }
121
122    for (size_t i = 0; i < pathsToRemove.size(); i++) {
123        mCache.removeAt(pathsToRemove.itemAt(i));
124    }
125}
126
127PathTexture* PathCache::get(SkPath* path, SkPaint* paint) {
128    PathCacheEntry entry(path, paint);
129
130    mLock.lock();
131    PathTexture* texture = mCache.get(entry);
132    mLock.unlock();
133
134    if (!texture) {
135        texture = addTexture(entry, path, paint);
136    } else if (path->getGenerationID() != texture->generation) {
137        mLock.lock();
138        mCache.remove(entry);
139        mLock.unlock();
140        texture = addTexture(entry, path, paint);
141    }
142
143    return texture;
144}
145
146PathTexture* PathCache::addTexture(const PathCacheEntry& entry,
147        const SkPath *path, const SkPaint* paint) {
148    const SkRect& bounds = path->getBounds();
149
150    const float pathWidth = fmax(bounds.width(), 1.0f);
151    const float pathHeight = fmax(bounds.height(), 1.0f);
152
153    if (pathWidth > mMaxTextureSize || pathHeight > mMaxTextureSize) {
154        LOGW("Path too large to be rendered into a texture");
155        return NULL;
156    }
157
158    const float offset = entry.strokeWidth * 1.5f;
159    const uint32_t width = uint32_t(pathWidth + offset * 2.0 + 0.5);
160    const uint32_t height = uint32_t(pathHeight + offset * 2.0 + 0.5);
161
162    const uint32_t size = width * height;
163    // Don't even try to cache a bitmap that's bigger than the cache
164    if (size < mMaxSize) {
165        mLock.lock();
166        while (mSize + size > mMaxSize) {
167            mCache.removeOldest();
168        }
169        mLock.unlock();
170    }
171
172    PathTexture* texture = new PathTexture;
173    texture->left = bounds.fLeft;
174    texture->top = bounds.fTop;
175    texture->offset = offset;
176    texture->width = width;
177    texture->height = height;
178    texture->generation = path->getGenerationID();
179
180    SkBitmap bitmap;
181    bitmap.setConfig(SkBitmap::kA8_Config, width, height);
182    bitmap.allocPixels();
183    bitmap.eraseColor(0);
184
185    SkPaint pathPaint(*paint);
186    if (!pathPaint.getXfermode()) {
187        SkXfermode* mode = SkXfermode::Create(SkXfermode::kSrc_Mode);
188        pathPaint.setXfermode(mode)->safeUnref();
189    }
190
191    SkCanvas canvas(bitmap);
192    canvas.translate(-bounds.fLeft + offset, -bounds.fTop + offset);
193    canvas.drawPath(*path, pathPaint);
194
195    generateTexture(bitmap, texture);
196
197    if (size < mMaxSize) {
198        mLock.lock();
199        mSize += size;
200        PATH_LOGD("PathCache::get: create path: name, size, mSize = %d, %d, %d",
201                texture->id, size, mSize);
202        mCache.put(entry, texture);
203        mLock.unlock();
204    } else {
205        texture->cleanup = true;
206    }
207
208    return texture;
209}
210
211void PathCache::clear() {
212    Mutex::Autolock _l(mLock);
213    mCache.clear();
214}
215
216void PathCache::generateTexture(SkBitmap& bitmap, Texture* texture) {
217    SkAutoLockPixels alp(bitmap);
218    if (!bitmap.readyToDraw()) {
219        LOGE("Cannot generate texture from bitmap");
220        return;
221    }
222
223    glGenTextures(1, &texture->id);
224
225    glBindTexture(GL_TEXTURE_2D, texture->id);
226    // Textures are Alpha8
227    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
228
229    texture->blend = true;
230    glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, texture->width, texture->height, 0,
231            GL_ALPHA, GL_UNSIGNED_BYTE, bitmap.getPixels());
232
233    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
234    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
235
236    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
237    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
238}
239
240}; // namespace uirenderer
241}; // namespace android
242