OffscreenBufferPool.cpp revision 8dc02f99d09130ace2ee738c2e689db1b3f33181 
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 "renderstate/RenderState.h"
21#include "utils/FatVector.h"
22#include "utils/TraceUtils.h"
23
24#include <utils/Color.h>
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, bool wideColorGamut)
38        : GpuMemoryTracker(GpuObjectType::OffscreenBuffer)
39        , renderState(renderState)
40        , viewportWidth(viewportWidth)
41        , viewportHeight(viewportHeight)
42        , texture(caches)
43        , wideColorGamut(wideColorGamut) {
44    uint32_t width = computeIdealDimension(viewportWidth);
45    uint32_t height = computeIdealDimension(viewportHeight);
46    ATRACE_FORMAT("Allocate %ux%u HW Layer", width, height);
47    caches.textureState().activateTexture(0);
48    texture.resize(width, height,
49            wideColorGamut ? GL_RGBA16F : caches.rgbaInternalFormat(), GL_RGBA);
50    texture.blend = true;
51    texture.setWrap(GL_CLAMP_TO_EDGE);
52    // not setting filter on texture, since it's set when drawing, based on transform
53}
54
55Rect OffscreenBuffer::getTextureCoordinates() {
56    const float texX = 1.0f / static_cast<float>(texture.width());
57    const float texY = 1.0f / static_cast<float>(texture.height());
58    return Rect(0, viewportHeight * texY, viewportWidth * texX, 0);
59}
60
61void OffscreenBuffer::dirty(Rect dirtyArea) {
62    dirtyArea.doIntersect(0, 0, viewportWidth, viewportHeight);
63    if (!dirtyArea.isEmpty()) {
64        region.orSelf(android::Rect(dirtyArea.left, dirtyArea.top,
65                dirtyArea.right, dirtyArea.bottom));
66    }
67}
68
69void OffscreenBuffer::updateMeshFromRegion() {
70    // avoid T-junctions as they cause artifacts in between the resultant
71    // geometry when complex transforms occur.
72    // TODO: generate the safeRegion only if necessary based on drawing transform
73    Region safeRegion = Region::createTJunctionFreeRegion(region);
74
75    size_t count;
76    const android::Rect* rects = safeRegion.getArray(&count);
77
78    const float texX = 1.0f / float(texture.width());
79    const float texY = 1.0f / float(texture.height());
80
81    FatVector<TextureVertex, 64> meshVector(count * 4); // uses heap if more than 64 vertices needed
82    TextureVertex* mesh = &meshVector[0];
83    for (size_t i = 0; i < count; i++) {
84        const android::Rect* r = &rects[i];
85
86        const float u1 = r->left * texX;
87        const float v1 = (viewportHeight - r->top) * texY;
88        const float u2 = r->right * texX;
89        const float v2 = (viewportHeight - r->bottom) * texY;
90
91        TextureVertex::set(mesh++, r->left, r->top, u1, v1);
92        TextureVertex::set(mesh++, r->right, r->top, u2, v1);
93        TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
94        TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
95    }
96    elementCount = count * 6;
97    renderState.meshState().genOrUpdateMeshBuffer(&vbo,
98            sizeof(TextureVertex) * count * 4,
99            &meshVector[0],
100            GL_DYNAMIC_DRAW); // TODO: GL_STATIC_DRAW if savelayer
101}
102
103uint32_t OffscreenBuffer::computeIdealDimension(uint32_t dimension) {
104    return uint32_t(ceilf(dimension / float(LAYER_SIZE)) * LAYER_SIZE);
105}
106
107OffscreenBuffer::~OffscreenBuffer() {
108    ATRACE_FORMAT("Destroy %ux%u HW Layer", texture.width(), texture.height());
109    texture.deleteTexture();
110    renderState.meshState().deleteMeshBuffer(vbo);
111    elementCount = 0;
112    vbo = 0;
113}
114
115///////////////////////////////////////////////////////////////////////////////
116// OffscreenBufferPool
117///////////////////////////////////////////////////////////////////////////////
118
119OffscreenBufferPool::OffscreenBufferPool()
120     // 4 screen-sized RGBA_8888 textures
121    : mMaxSize(DeviceInfo::multiplyByResolution(4 * 4)) {
122}
123
124OffscreenBufferPool::~OffscreenBufferPool() {
125    clear(); // TODO: unique_ptr?
126}
127
128int OffscreenBufferPool::Entry::compare(const Entry& lhs, const Entry& rhs) {
129    int deltaInt = int(lhs.width) - int(rhs.width);
130    if (deltaInt != 0) return deltaInt;
131
132    deltaInt = int(lhs.height) - int(rhs.height);
133    if (deltaInt != 0) return deltaInt;
134
135    return int(lhs.wideColorGamut) - int(rhs.wideColorGamut);
136}
137
138void OffscreenBufferPool::clear() {
139    for (auto& entry : mPool) {
140        delete entry.layer;
141    }
142    mPool.clear();
143    mSize = 0;
144}
145
146OffscreenBuffer* OffscreenBufferPool::get(RenderState& renderState,
147        const uint32_t width, const uint32_t height, bool wideColorGamut) {
148    OffscreenBuffer* layer = nullptr;
149
150    Entry entry(width, height, wideColorGamut);
151    auto iter = mPool.find(entry);
152
153    if (iter != mPool.end()) {
154        entry = *iter;
155        mPool.erase(iter);
156
157        layer = entry.layer;
158        layer->viewportWidth = width;
159        layer->viewportHeight = height;
160        mSize -= layer->getSizeInBytes();
161    } else {
162        layer = new OffscreenBuffer(renderState, Caches::getInstance(),
163                width, height, wideColorGamut);
164    }
165
166    return layer;
167}
168
169OffscreenBuffer* OffscreenBufferPool::resize(OffscreenBuffer* layer,
170        const uint32_t width, const uint32_t height) {
171    RenderState& renderState = layer->renderState;
172    if (layer->texture.width() == OffscreenBuffer::computeIdealDimension(width)
173            && layer->texture.height() == OffscreenBuffer::computeIdealDimension(height)) {
174        // resize in place
175        layer->viewportWidth = width;
176        layer->viewportHeight = height;
177
178        // entire area will be repainted (and may be smaller) so clear usage region
179        layer->region.clear();
180        return layer;
181    }
182    putOrDelete(layer);
183    return get(renderState, width, height, layer->wideColorGamut);
184}
185
186void OffscreenBufferPool::dump() {
187    for (auto entry : mPool) {
188        ALOGD("  Layer size %dx%d", entry.width, entry.height);
189    }
190}
191
192void OffscreenBufferPool::putOrDelete(OffscreenBuffer* layer) {
193    const uint32_t size = layer->getSizeInBytes();
194    // Don't even try to cache a layer that's bigger than the cache
195    if (size < mMaxSize) {
196        // TODO: Use an LRU
197        while (mSize + size > mMaxSize) {
198            OffscreenBuffer* victim = mPool.begin()->layer;
199            mSize -= victim->getSizeInBytes();
200            delete victim;
201            mPool.erase(mPool.begin());
202        }
203
204        // clear region, since it's no longer valid
205        layer->region.clear();
206
207        Entry entry(layer);
208
209        mPool.insert(entry);
210        mSize += size;
211    } else {
212        delete layer;
213    }
214}
215
216}; // namespace uirenderer
217}; // namespace android
218