PixelBuffer.cpp revision 51d6a3db97bdd5315f1a17a4b447d10a92217b98 
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#define LOG_TAG "OpenGLRenderer"
18
19#include <utils/Log.h>
20
21#include "Caches.h"
22#include "Debug.h"
23#include "Extensions.h"
24#include "PixelBuffer.h"
25#include "Properties.h"
26
27namespace android {
28namespace uirenderer {
29
30///////////////////////////////////////////////////////////////////////////////
31// CPU pixel buffer
32///////////////////////////////////////////////////////////////////////////////
33
34class CpuPixelBuffer: public PixelBuffer {
35public:
36    CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
37
38    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
39    void unmap();
40
41    uint8_t* getMappedPointer() const;
42
43    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
44
45private:
46    std::unique_ptr<uint8_t[]> mBuffer;
47};
48
49CpuPixelBuffer::CpuPixelBuffer(GLenum format, uint32_t width, uint32_t height)
50        : PixelBuffer(format, width, height)
51        , mBuffer(new uint8_t[width * height * formatSize(format)]) {
52}
53
54uint8_t* CpuPixelBuffer::map(AccessMode mode) {
55    if (mAccessMode == kAccessMode_None) {
56        mAccessMode = mode;
57    }
58    return mBuffer.get();
59}
60
61void CpuPixelBuffer::unmap() {
62    mAccessMode = kAccessMode_None;
63}
64
65uint8_t* CpuPixelBuffer::getMappedPointer() const {
66    return mAccessMode == kAccessMode_None ? nullptr : mBuffer.get();
67}
68
69void CpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
70    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height,
71            mFormat, GL_UNSIGNED_BYTE, &mBuffer[offset]);
72}
73
74///////////////////////////////////////////////////////////////////////////////
75// GPU pixel buffer
76///////////////////////////////////////////////////////////////////////////////
77
78class GpuPixelBuffer: public PixelBuffer {
79public:
80    GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height);
81    ~GpuPixelBuffer();
82
83    uint8_t* map(AccessMode mode = kAccessMode_ReadWrite);
84    void unmap();
85
86    uint8_t* getMappedPointer() const;
87
88    void upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset);
89
90private:
91    GLuint mBuffer;
92    uint8_t* mMappedPointer;
93    Caches& mCaches;
94};
95
96GpuPixelBuffer::GpuPixelBuffer(GLenum format, uint32_t width, uint32_t height):
97        PixelBuffer(format, width, height), mMappedPointer(0), mCaches(Caches::getInstance()) {
98    glGenBuffers(1, &mBuffer);
99    mCaches.bindPixelBuffer(mBuffer);
100    glBufferData(GL_PIXEL_UNPACK_BUFFER, getSize(), NULL, GL_DYNAMIC_DRAW);
101    mCaches.unbindPixelBuffer();
102}
103
104GpuPixelBuffer::~GpuPixelBuffer() {
105    glDeleteBuffers(1, &mBuffer);
106}
107
108uint8_t* GpuPixelBuffer::map(AccessMode mode) {
109    if (mAccessMode == kAccessMode_None) {
110        mCaches.bindPixelBuffer(mBuffer);
111        mMappedPointer = (uint8_t*) glMapBufferRange(GL_PIXEL_UNPACK_BUFFER, 0, getSize(), mode);
112#if DEBUG_OPENGL
113        if (!mMappedPointer) {
114            GLenum status = GL_NO_ERROR;
115            while ((status = glGetError()) != GL_NO_ERROR) {
116                ALOGE("Could not map GPU pixel buffer: 0x%x", status);
117            }
118        }
119#endif
120        mAccessMode = mode;
121    }
122
123    return mMappedPointer;
124}
125
126void GpuPixelBuffer::unmap() {
127    if (mAccessMode != kAccessMode_None) {
128        if (mMappedPointer) {
129            mCaches.bindPixelBuffer(mBuffer);
130            GLboolean status = glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
131            if (status == GL_FALSE) {
132                ALOGE("Corrupted GPU pixel buffer");
133            }
134        }
135        mAccessMode = kAccessMode_None;
136        mMappedPointer = NULL;
137    }
138}
139
140uint8_t* GpuPixelBuffer::getMappedPointer() const {
141    return mMappedPointer;
142}
143
144void GpuPixelBuffer::upload(uint32_t x, uint32_t y, uint32_t width, uint32_t height, int offset) {
145    // If the buffer is not mapped, unmap() will not bind it
146    mCaches.bindPixelBuffer(mBuffer);
147    unmap();
148    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, width, height, mFormat,
149            GL_UNSIGNED_BYTE, reinterpret_cast<void*>(offset));
150}
151
152///////////////////////////////////////////////////////////////////////////////
153// Factory
154///////////////////////////////////////////////////////////////////////////////
155
156PixelBuffer* PixelBuffer::create(GLenum format, uint32_t width, uint32_t height, BufferType type) {
157    if (type == kBufferType_Auto && Caches::getInstance().gpuPixelBuffersEnabled) {
158        return new GpuPixelBuffer(format, width, height);
159    }
160    return new CpuPixelBuffer(format, width, height);
161}
162
163}; // namespace uirenderer
164}; // namespace android
165