OffscreenBufferPool.cpp revision aff230f6f9f9e44a5e111ba3f087d03f7a0e24f3 
1/*
2 * Copyright (C) 2015 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#include "OffscreenBufferPool.h"
18
19#include "Caches.h"
20#include "Properties.h"
21#include "renderstate/RenderState.h"
22#include "utils/FatVector.h"
23#include "utils/TraceUtils.h"
24
25#include <utils/Log.h>
26
27#include <GLES2/gl2.h>
28
29namespace android {
30namespace uirenderer {
31
32////////////////////////////////////////////////////////////////////////////////
33// OffscreenBuffer
34////////////////////////////////////////////////////////////////////////////////
35
36OffscreenBuffer::OffscreenBuffer(RenderState& renderState, Caches& caches,
37        uint32_t viewportWidth, uint32_t viewportHeight)
38        : GpuMemoryTracker(GpuObjectType::OffscreenBuffer)
39        , renderState(renderState)
40        , viewportWidth(viewportWidth)
41        , viewportHeight(viewportHeight)
42        , texture(caches) {
43    uint32_t width = computeIdealDimension(viewportWidth);
44    uint32_t height = computeIdealDimension(viewportHeight);
45    ATRACE_FORMAT("Allocate %ux%u HW Layer", width, height);
46    caches.textureState().activateTexture(0);
47    texture.resize(width, height, GL_RGBA);
48    texture.blend = true;
49    texture.setWrap(GL_CLAMP_TO_EDGE);
50    // not setting filter on texture, since it's set when drawing, based on transform
51}
52
53Rect OffscreenBuffer::getTextureCoordinates() {
54    const float texX = 1.0f / static_cast<float>(texture.width());
55    const float texY = 1.0f / static_cast<float>(texture.height());
56    return Rect(0, viewportHeight * texY, viewportWidth * texX, 0);
57}
58
59void OffscreenBuffer::dirty(Rect dirtyArea) {
60    dirtyArea.doIntersect(0, 0, viewportWidth, viewportHeight);
61    if (!dirtyArea.isEmpty()) {
62        region.orSelf(android::Rect(dirtyArea.left, dirtyArea.top,
63                dirtyArea.right, dirtyArea.bottom));
64    }
65}
66
67void OffscreenBuffer::updateMeshFromRegion() {
68    // avoid T-junctions as they cause artifacts in between the resultant
69    // geometry when complex transforms occur.
70    // TODO: generate the safeRegion only if necessary based on drawing transform
71    Region safeRegion = Region::createTJunctionFreeRegion(region);
72
73    size_t count;
74    const android::Rect* rects = safeRegion.getArray(&count);
75
76    const float texX = 1.0f / float(texture.width());
77    const float texY = 1.0f / float(texture.height());
78
79    FatVector<TextureVertex, 64> meshVector(count * 4); // uses heap if more than 64 vertices needed
80    TextureVertex* mesh = &meshVector[0];
81    for (size_t i = 0; i < count; i++) {
82        const android::Rect* r = &rects[i];
83
84        const float u1 = r->left * texX;
85        const float v1 = (viewportHeight - r->top) * texY;
86        const float u2 = r->right * texX;
87        const float v2 = (viewportHeight - r->bottom) * texY;
88
89        TextureVertex::set(mesh++, r->left, r->top, u1, v1);
90        TextureVertex::set(mesh++, r->right, r->top, u2, v1);
91        TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
92        TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
93    }
94    elementCount = count * 6;
95    renderState.meshState().genOrUpdateMeshBuffer(&vbo,
96            sizeof(TextureVertex) * count * 4,
97            &meshVector[0],
98            GL_DYNAMIC_DRAW); // TODO: GL_STATIC_DRAW if savelayer
99}
100
101uint32_t OffscreenBuffer::computeIdealDimension(uint32_t dimension) {
102    return uint32_t(ceilf(dimension / float(LAYER_SIZE)) * LAYER_SIZE);
103}
104
105OffscreenBuffer::~OffscreenBuffer() {
106    ATRACE_FORMAT("Destroy %ux%u HW Layer", texture.width(), texture.height());
107    texture.deleteTexture();
108    renderState.meshState().deleteMeshBuffer(vbo);
109    elementCount = 0;
110    vbo = 0;
111}
112
113///////////////////////////////////////////////////////////////////////////////
114// OffscreenBufferPool
115///////////////////////////////////////////////////////////////////////////////
116
117OffscreenBufferPool::OffscreenBufferPool()
118    : mMaxSize(Properties::layerPoolSize) {
119}
120
121OffscreenBufferPool::~OffscreenBufferPool() {
122    clear(); // TODO: unique_ptr?
123}
124
125int OffscreenBufferPool::Entry::compare(const Entry& lhs, const Entry& rhs) {
126    int deltaInt = int(lhs.width) - int(rhs.width);
127    if (deltaInt != 0) return deltaInt;
128
129    return int(lhs.height) - int(rhs.height);
130}
131
132void OffscreenBufferPool::clear() {
133    for (auto& entry : mPool) {
134        delete entry.layer;
135    }
136    mPool.clear();
137    mSize = 0;
138}
139
140OffscreenBuffer* OffscreenBufferPool::get(RenderState& renderState,
141        const uint32_t width, const uint32_t height) {
142    OffscreenBuffer* layer = nullptr;
143
144    Entry entry(width, height);
145    auto iter = mPool.find(entry);
146
147    if (iter != mPool.end()) {
148        entry = *iter;
149        mPool.erase(iter);
150
151        layer = entry.layer;
152        layer->viewportWidth = width;
153        layer->viewportHeight = height;
154        mSize -= layer->getSizeInBytes();
155    } else {
156        layer = new OffscreenBuffer(renderState, Caches::getInstance(), width, height);
157    }
158
159    return layer;
160}
161
162OffscreenBuffer* OffscreenBufferPool::resize(OffscreenBuffer* layer,
163        const uint32_t width, const uint32_t height) {
164    RenderState& renderState = layer->renderState;
165    if (layer->texture.width() == OffscreenBuffer::computeIdealDimension(width)
166            && layer->texture.height() == OffscreenBuffer::computeIdealDimension(height)) {
167        // resize in place
168        layer->viewportWidth = width;
169        layer->viewportHeight = height;
170
171        // entire area will be repainted (and may be smaller) so clear usage region
172        layer->region.clear();
173        return layer;
174    }
175    putOrDelete(layer);
176    return get(renderState, width, height);
177}
178
179void OffscreenBufferPool::dump() {
180    for (auto entry : mPool) {
181        ALOGD("  Layer size %dx%d", entry.width, entry.height);
182    }
183}
184
185void OffscreenBufferPool::putOrDelete(OffscreenBuffer* layer) {
186    const uint32_t size = layer->getSizeInBytes();
187    // Don't even try to cache a layer that's bigger than the cache
188    if (size < mMaxSize) {
189        // TODO: Use an LRU
190        while (mSize + size > mMaxSize) {
191            OffscreenBuffer* victim = mPool.begin()->layer;
192            mSize -= victim->getSizeInBytes();
193            delete victim;
194            mPool.erase(mPool.begin());
195        }
196
197        // clear region, since it's no longer valid
198        layer->region.clear();
199
200        Entry entry(layer);
201
202        mPool.insert(entry);
203        mSize += size;
204    } else {
205        delete layer;
206    }
207}
208
209}; // namespace uirenderer
210}; // namespace android
211