PixelBuffer.cpp revision 5a4690bf26932c0d6940e4af8516d920e09ae81a 
1/*
2 * Copyright (C) 2013 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 "PixelBuffer.h"
18
19#include "Debug.h"
20#include "Extensions.h"
21#include "Properties.h"
22#include "renderstate/RenderState.h"
23
24#include <utils/Log.h>
25
26namespace android {
27namespace uirenderer {
28
29///////////////////////////////////////////////////////////////////////////////
30// CPU pixel buffer
31///////////////////////////////////////////////////////////////////////////////
32
33class CpuPixelBuffer: public PixelBuffer {
34public:
35    CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
36
37    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite) override;
38    void unmap() override;
39
40    uint8_t* getMappedPointer() const override;
41
42    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) override;
43
44private:
45    std::unique_ptr<uint8_t[]> mBuffer;
46};
47
48CpuPixelBuffer::CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height)
49        : PixelBuffer(format, width, height)
50        , mBuffer(new uint8_t[width * height * formatSize(format)]) {
51}
52
53uint8_t* CpuPixelBuffer::map(AccessMode mode) {
54    if (mAccessMode == kAccessMode_None) {
55        mAccessMode = mode;
56    }
57    return mBuffer.get();
58}
59
60void CpuPixelBuffer::unmap() {
61    mAccessMode = kAccessMode_None;
62}
63
64uint8_t* CpuPixelBuffer::getMappedPointer() const {
65    return mAccessMode == kAccessMode_None ? nullptr : mBuffer.get();
66}
67
68void CpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
69    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height,
70            mFormat, GL_UNSIGNED_BYTE, &mBuffer[offset]);
71}
72
73///////////////////////////////////////////////////////////////////////////////
74// GPU pixel buffer
75///////////////////////////////////////////////////////////////////////////////
76
77class GpuPixelBuffer: public PixelBuffer {
78public:
79    GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
80    ~GpuPixelBuffer();
81
82    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite) override;
83    void unmap() override;
84
85    uint8_t* getMappedPointer() const override;
86
87    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) override;
88
89private:
90    GLuint mBuffer;
91    uint8_t* mMappedPointer;
92    Caches& mCaches;
93};
94
95GpuPixelBuffer::GpuPixelBuffer(GLenum format,
96        uint32_t width, uint32_t height)
97        : PixelBuffer(format, width, height)
98        , mMappedPointer(nullptr)
99        , mCaches(Caches::getInstance()){
100    glGenBuffers(1, &mBuffer);
101
102    mCaches.pixelBufferState().bind(mBuffer);
103    glBufferData(GL_PIXEL_UNPACK_BUFFER, getSize(), nullptr, GL_DYNAMIC_DRAW);
104    mCaches.pixelBufferState().unbind();
105}
106
107GpuPixelBuffer::~GpuPixelBuffer() {
108    glDeleteBuffers(1, &mBuffer);
109}
110
111uint8_t* GpuPixelBuffer::map(AccessMode mode) {
112    if (mAccessMode == kAccessMode_None) {
113        mCaches.pixelBufferState().bind(mBuffer);
114        mMappedPointer = (uint8_t*) glMapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, getSize(), mode);
115#if DEBUG_OPENGL
116        if (!mMappedPointer) {
117            GLenum status = GL_NO_ERROR;
118            while ((status = glGetError()) != GL_NO_ERROR) {
119                ALOGE("Could not map GPU pixel buffer: 0x%x", status);
120            }
121        }
122#endif
123        mAccessMode = mode;
124    }
125
126    return mMappedPointer;
127}
128
129void GpuPixelBuffer::unmap() {
130    if (mAccessMode != kAccessMode_None) {
131        if (mMappedPointer) {
132            mCaches.pixelBufferState().bind(mBuffer);
133            GLboolean status = glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
134            if (status == GL_FALSE) {
135                ALOGE("Corrupted GPU pixel buffer");
136            }
137        }
138        mAccessMode = kAccessMode_None;
139        mMappedPointer = nullptr;
140    }
141}
142
143uint8_t* GpuPixelBuffer::getMappedPointer() const {
144    return mMappedPointer;
145}
146
147void GpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
148    // If the buffer is not mapped, unmap() will not bind it
149    mCaches.pixelBufferState().bind(mBuffer);
150    unmap();
151    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, mFormat,
152            GL_UNSIGNED_BYTE, reinterpret_cast<void*>(offset));
153}
154
155///////////////////////////////////////////////////////////////////////////////
156// Factory
157///////////////////////////////////////////////////////////////////////////////
158
159PixelBuffer* PixelBuffer::create(GLenum format,
160        uint32_t width, uint32_t height, BufferType type) {
161    if (type == kBufferType_Auto && Caches::getInstance().gpuPixelBuffersEnabled) {
162        return new GpuPixelBuffer(format, width, height);
163    }
164    return new CpuPixelBuffer(format, width, height);
165}
166
167}; // namespace uirenderer
168}; // namespace android
169