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/Color.h>
26 #include <utils/Log.h>
27 
28 #include <GLES2/gl2.h>
29 
30 namespace android {
31 namespace uirenderer {
32 
33 ////////////////////////////////////////////////////////////////////////////////
34 // OffscreenBuffer
35 ////////////////////////////////////////////////////////////////////////////////
36 
OffscreenBuffer(RenderState & renderState,Caches & caches,uint32_t viewportWidth,uint32_t viewportHeight)37 OffscreenBuffer::OffscreenBuffer(RenderState& renderState, Caches& caches,
38         uint32_t viewportWidth, uint32_t viewportHeight)
39         : GpuMemoryTracker(GpuObjectType::OffscreenBuffer)
40         , renderState(renderState)
41         , viewportWidth(viewportWidth)
42         , viewportHeight(viewportHeight)
43         , texture(caches) {
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, caches.rgbaInternalFormat(), GL_RGBA);
49     texture.blend = true;
50     texture.setWrap(GL_CLAMP_TO_EDGE);
51     // not setting filter on texture, since it's set when drawing, based on transform
52 }
53 
getTextureCoordinates()54 Rect OffscreenBuffer::getTextureCoordinates() {
55     const float texX = 1.0f / static_cast<float>(texture.width());
56     const float texY = 1.0f / static_cast<float>(texture.height());
57     return Rect(0, viewportHeight * texY, viewportWidth * texX, 0);
58 }
59 
dirty(Rect dirtyArea)60 void OffscreenBuffer::dirty(Rect dirtyArea) {
61     dirtyArea.doIntersect(0, 0, viewportWidth, viewportHeight);
62     if (!dirtyArea.isEmpty()) {
63         region.orSelf(android::Rect(dirtyArea.left, dirtyArea.top,
64                 dirtyArea.right, dirtyArea.bottom));
65     }
66 }
67 
updateMeshFromRegion()68 void OffscreenBuffer::updateMeshFromRegion() {
69     // avoid T-junctions as they cause artifacts in between the resultant
70     // geometry when complex transforms occur.
71     // TODO: generate the safeRegion only if necessary based on drawing transform
72     Region safeRegion = Region::createTJunctionFreeRegion(region);
73 
74     size_t count;
75     const android::Rect* rects = safeRegion.getArray(&count);
76 
77     const float texX = 1.0f / float(texture.width());
78     const float texY = 1.0f / float(texture.height());
79 
80     FatVector<TextureVertex, 64> meshVector(count * 4); // uses heap if more than 64 vertices needed
81     TextureVertex* mesh = &meshVector[0];
82     for (size_t i = 0; i < count; i++) {
83         const android::Rect* r = &rects[i];
84 
85         const float u1 = r->left * texX;
86         const float v1 = (viewportHeight - r->top) * texY;
87         const float u2 = r->right * texX;
88         const float v2 = (viewportHeight - r->bottom) * texY;
89 
90         TextureVertex::set(mesh++, r->left, r->top, u1, v1);
91         TextureVertex::set(mesh++, r->right, r->top, u2, v1);
92         TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
93         TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
94     }
95     elementCount = count * 6;
96     renderState.meshState().genOrUpdateMeshBuffer(&vbo,
97             sizeof(TextureVertex) * count * 4,
98             &meshVector[0],
99             GL_DYNAMIC_DRAW); // TODO: GL_STATIC_DRAW if savelayer
100 }
101 
computeIdealDimension(uint32_t dimension)102 uint32_t OffscreenBuffer::computeIdealDimension(uint32_t dimension) {
103     return uint32_t(ceilf(dimension / float(LAYER_SIZE)) * LAYER_SIZE);
104 }
105 
~OffscreenBuffer()106 OffscreenBuffer::~OffscreenBuffer() {
107     ATRACE_FORMAT("Destroy %ux%u HW Layer", texture.width(), texture.height());
108     texture.deleteTexture();
109     renderState.meshState().deleteMeshBuffer(vbo);
110     elementCount = 0;
111     vbo = 0;
112 }
113 
114 ///////////////////////////////////////////////////////////////////////////////
115 // OffscreenBufferPool
116 ///////////////////////////////////////////////////////////////////////////////
117 
OffscreenBufferPool()118 OffscreenBufferPool::OffscreenBufferPool()
119     : mMaxSize(Properties::layerPoolSize) {
120 }
121 
~OffscreenBufferPool()122 OffscreenBufferPool::~OffscreenBufferPool() {
123     clear(); // TODO: unique_ptr?
124 }
125 
compare(const Entry & lhs,const Entry & rhs)126 int OffscreenBufferPool::Entry::compare(const Entry& lhs, const Entry& rhs) {
127     int deltaInt = int(lhs.width) - int(rhs.width);
128     if (deltaInt != 0) return deltaInt;
129 
130     return int(lhs.height) - int(rhs.height);
131 }
132 
clear()133 void OffscreenBufferPool::clear() {
134     for (auto& entry : mPool) {
135         delete entry.layer;
136     }
137     mPool.clear();
138     mSize = 0;
139 }
140 
get(RenderState & renderState,const uint32_t width,const uint32_t height)141 OffscreenBuffer* OffscreenBufferPool::get(RenderState& renderState,
142         const uint32_t width, const uint32_t height) {
143     OffscreenBuffer* layer = nullptr;
144 
145     Entry entry(width, height);
146     auto iter = mPool.find(entry);
147 
148     if (iter != mPool.end()) {
149         entry = *iter;
150         mPool.erase(iter);
151 
152         layer = entry.layer;
153         layer->viewportWidth = width;
154         layer->viewportHeight = height;
155         mSize -= layer->getSizeInBytes();
156     } else {
157         layer = new OffscreenBuffer(renderState, Caches::getInstance(), width, height);
158     }
159 
160     return layer;
161 }
162 
resize(OffscreenBuffer * layer,const uint32_t width,const uint32_t height)163 OffscreenBuffer* OffscreenBufferPool::resize(OffscreenBuffer* layer,
164         const uint32_t width, const uint32_t height) {
165     RenderState& renderState = layer->renderState;
166     if (layer->texture.width() == OffscreenBuffer::computeIdealDimension(width)
167             && layer->texture.height() == OffscreenBuffer::computeIdealDimension(height)) {
168         // resize in place
169         layer->viewportWidth = width;
170         layer->viewportHeight = height;
171 
172         // entire area will be repainted (and may be smaller) so clear usage region
173         layer->region.clear();
174         return layer;
175     }
176     putOrDelete(layer);
177     return get(renderState, width, height);
178 }
179 
dump()180 void OffscreenBufferPool::dump() {
181     for (auto entry : mPool) {
182         ALOGD("  Layer size %dx%d", entry.width, entry.height);
183     }
184 }
185 
putOrDelete(OffscreenBuffer * layer)186 void OffscreenBufferPool::putOrDelete(OffscreenBuffer* layer) {
187     const uint32_t size = layer->getSizeInBytes();
188     // Don't even try to cache a layer that's bigger than the cache
189     if (size < mMaxSize) {
190         // TODO: Use an LRU
191         while (mSize + size > mMaxSize) {
192             OffscreenBuffer* victim = mPool.begin()->layer;
193             mSize -= victim->getSizeInBytes();
194             delete victim;
195             mPool.erase(mPool.begin());
196         }
197 
198         // clear region, since it's no longer valid
199         layer->region.clear();
200 
201         Entry entry(layer);
202 
203         mPool.insert(entry);
204         mSize += size;
205     } else {
206         delete layer;
207     }
208 }
209 
210 }; // namespace uirenderer
211 }; // namespace android
212