aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/gpu/gl/GrGLBufferImpl.cpp
blob: 52ef946cff6db24db792bf912a0a43c25b497047 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "GrGLBufferImpl.h"
#include "GrGLGpu.h"

#define GL_CALL(GPU, X) GR_GL_CALL(GPU->glInterface(), X)

#ifdef SK_DEBUG
#define VALIDATE() this->validate()
#else
#define VALIDATE() do {} while(false)
#endif

// GL_STREAM_DRAW triggers an optimization in Chromium's GPU process where a client's vertex buffer
// objects are implemented as client-side-arrays on tile-deferred architectures.
#define DYNAMIC_USAGE_PARAM GR_GL_STREAM_DRAW

GrGLBufferImpl::GrGLBufferImpl(GrGLGpu* gpu, const Desc& desc, GrGLenum bufferType)
    : fDesc(desc)
    , fBufferType(bufferType)
    , fMapPtr(nullptr) {
    if (0 == desc.fID) {
        if (gpu->caps()->mustClearUploadedBufferData()) {
            fCPUData = sk_calloc_throw(desc.fSizeInBytes);
        } else {
            fCPUData = sk_malloc_flags(desc.fSizeInBytes, SK_MALLOC_THROW);
        }
        fGLSizeInBytes = 0;
    } else {
        fCPUData = nullptr;
        // We assume that the GL buffer was created at the desc's size initially.
        fGLSizeInBytes = fDesc.fSizeInBytes;
    }
    VALIDATE();
}

void GrGLBufferImpl::release(GrGLGpu* gpu) {
    VALIDATE();
    // make sure we've not been abandoned or already released
    if (fCPUData) {
        sk_free(fCPUData);
        fCPUData = nullptr;
    } else if (fDesc.fID) {
        GL_CALL(gpu, DeleteBuffers(1, &fDesc.fID));
        if (GR_GL_ARRAY_BUFFER == fBufferType) {
            gpu->notifyVertexBufferDelete(fDesc.fID);
        } else {
            SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
            gpu->notifyIndexBufferDelete(fDesc.fID);
        }
        fDesc.fID = 0;
        fGLSizeInBytes = 0;
    }
    fMapPtr = nullptr;
    VALIDATE();
}

void GrGLBufferImpl::abandon() {
    fDesc.fID = 0;
    fGLSizeInBytes = 0;
    fMapPtr = nullptr;
    sk_free(fCPUData);
    fCPUData = nullptr;
    VALIDATE();
}

void GrGLBufferImpl::bind(GrGLGpu* gpu) const {
    VALIDATE();
    if (GR_GL_ARRAY_BUFFER == fBufferType) {
        gpu->bindVertexBuffer(fDesc.fID);
    } else {
        SkASSERT(GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
        gpu->bindIndexBufferAndDefaultVertexArray(fDesc.fID);
    }
    VALIDATE();
}

void* GrGLBufferImpl::map(GrGLGpu* gpu) {
    VALIDATE();
    SkASSERT(!this->isMapped());
    if (0 == fDesc.fID) {
        fMapPtr = fCPUData;
    } else {
        switch (gpu->glCaps().mapBufferType()) {
            case GrGLCaps::kNone_MapBufferType:
                VALIDATE();
                return nullptr;
            case GrGLCaps::kMapBuffer_MapBufferType:
                this->bind(gpu);
                // Let driver know it can discard the old data
                if (GR_GL_USE_BUFFER_DATA_NULL_HINT || fDesc.fSizeInBytes != fGLSizeInBytes) {
                    fGLSizeInBytes = fDesc.fSizeInBytes;
                    GL_CALL(gpu,
                            BufferData(fBufferType, fGLSizeInBytes, nullptr,
                                       fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                }
                GR_GL_CALL_RET(gpu->glInterface(), fMapPtr,
                               MapBuffer(fBufferType, GR_GL_WRITE_ONLY));
                break;
            case GrGLCaps::kMapBufferRange_MapBufferType: {
                this->bind(gpu);
                // Make sure the GL buffer size agrees with fDesc before mapping.
                if (fDesc.fSizeInBytes != fGLSizeInBytes) {
                    fGLSizeInBytes = fDesc.fSizeInBytes;
                    GL_CALL(gpu,
                            BufferData(fBufferType, fGLSizeInBytes, nullptr,
                                       fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                }
                static const GrGLbitfield kAccess = GR_GL_MAP_INVALIDATE_BUFFER_BIT |
                                                    GR_GL_MAP_WRITE_BIT;
                GR_GL_CALL_RET(gpu->glInterface(),
                               fMapPtr,
                               MapBufferRange(fBufferType, 0, fGLSizeInBytes, kAccess));
                break;
            }
            case GrGLCaps::kChromium_MapBufferType:
                this->bind(gpu);
                // Make sure the GL buffer size agrees with fDesc before mapping.
                if (fDesc.fSizeInBytes != fGLSizeInBytes) {
                    fGLSizeInBytes = fDesc.fSizeInBytes;
                    GL_CALL(gpu,
                            BufferData(fBufferType, fGLSizeInBytes, nullptr,
                                       fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW));
                }
                GR_GL_CALL_RET(gpu->glInterface(),
                               fMapPtr,
                               MapBufferSubData(fBufferType, 0, fGLSizeInBytes, GR_GL_WRITE_ONLY));
                break;
        }
    }
    VALIDATE();
    return fMapPtr;
}

void GrGLBufferImpl::unmap(GrGLGpu* gpu) {
    VALIDATE();
    SkASSERT(this->isMapped());
    if (0 != fDesc.fID) {
        switch (gpu->glCaps().mapBufferType()) {
            case GrGLCaps::kNone_MapBufferType:
                SkDEBUGFAIL("Shouldn't get here.");
                return;
            case GrGLCaps::kMapBuffer_MapBufferType: // fall through
            case GrGLCaps::kMapBufferRange_MapBufferType:
                this->bind(gpu);
                GL_CALL(gpu, UnmapBuffer(fBufferType));
                break;
            case GrGLCaps::kChromium_MapBufferType:
                this->bind(gpu);
                GR_GL_CALL(gpu->glInterface(), UnmapBufferSubData(fMapPtr));
                break;
        }
    }
    fMapPtr = nullptr;
}

bool GrGLBufferImpl::isMapped() const {
    VALIDATE();
    return SkToBool(fMapPtr);
}

bool GrGLBufferImpl::updateData(GrGLGpu* gpu, const void* src, size_t srcSizeInBytes) {
    SkASSERT(!this->isMapped());
    VALIDATE();
    if (srcSizeInBytes > fDesc.fSizeInBytes) {
        return false;
    }
    if (0 == fDesc.fID) {
        memcpy(fCPUData, src, srcSizeInBytes);
        return true;
    }
    this->bind(gpu);
    GrGLenum usage = fDesc.fDynamic ? DYNAMIC_USAGE_PARAM : GR_GL_STATIC_DRAW;

#if GR_GL_USE_BUFFER_DATA_NULL_HINT
    if (fDesc.fSizeInBytes == srcSizeInBytes) {
        GL_CALL(gpu, BufferData(fBufferType, (GrGLsizeiptr) srcSizeInBytes, src, usage));
    } else {
        // Before we call glBufferSubData we give the driver a hint using
        // glBufferData with nullptr. This makes the old buffer contents
        // inaccessible to future draws. The GPU may still be processing
        // draws that reference the old contents. With this hint it can
        // assign a different allocation for the new contents to avoid
        // flushing the gpu past draws consuming the old contents.
        fGLSizeInBytes = fDesc.fSizeInBytes;
        GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, nullptr, usage));
        GL_CALL(gpu, BufferSubData(fBufferType, 0, (GrGLsizeiptr) srcSizeInBytes, src));
    }
#else
    // Note that we're cheating on the size here. Currently no methods
    // allow a partial update that preserves contents of non-updated
    // portions of the buffer (map() does a glBufferData(..size, nullptr..))
    bool doSubData = false;
#if GR_GL_MAC_BUFFER_OBJECT_PERFOMANCE_WORKAROUND
    static int N = 0;
    // 128 was chosen experimentally. At 256 a slight hitchiness was noticed
    // when dragging a Chromium window around with a canvas tab backgrounded.
    doSubData = 0 == (N % 128);
    ++N;
#endif
    if (doSubData) {
        // The workaround is to do a glBufferData followed by glBufferSubData.
        // Chromium's command buffer may turn a glBufferSubData where the size
        // exactly matches the buffer size into a glBufferData. So we tack 1
        // extra byte onto the glBufferData.
        fGLSizeInBytes = srcSizeInBytes + 1;
        GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, nullptr, usage));
        GL_CALL(gpu, BufferSubData(fBufferType, 0, srcSizeInBytes, src));
    } else {
        fGLSizeInBytes = srcSizeInBytes;
        GL_CALL(gpu, BufferData(fBufferType, fGLSizeInBytes, src, usage));
    }
#endif
    return true;
}

void GrGLBufferImpl::validate() const {
    SkASSERT(GR_GL_ARRAY_BUFFER == fBufferType || GR_GL_ELEMENT_ARRAY_BUFFER == fBufferType);
    // The following assert isn't valid when the buffer has been abandoned:
    // SkASSERT((0 == fDesc.fID) == (fCPUData));
    SkASSERT(nullptr == fCPUData || 0 == fGLSizeInBytes);
    SkASSERT(nullptr == fMapPtr || fCPUData || fGLSizeInBytes == fDesc.fSizeInBytes);
    SkASSERT(nullptr == fCPUData || nullptr == fMapPtr || fCPUData == fMapPtr);
}