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
|
/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#include "SoftwareVsyncSource.h"
#include "base/task.h"
#include "gfxPlatform.h"
#include "nsThreadUtils.h"
using namespace mozilla;
SoftwareVsyncSource::SoftwareVsyncSource() {
MOZ_ASSERT(NS_IsMainThread());
mGlobalDisplay = new SoftwareDisplay();
}
SoftwareVsyncSource::~SoftwareVsyncSource() {
MOZ_ASSERT(NS_IsMainThread());
mGlobalDisplay = nullptr;
}
SoftwareDisplay::SoftwareDisplay() : mVsyncEnabled(false) {
// Mimic 60 fps
MOZ_ASSERT(NS_IsMainThread());
const double rate = 1000.0 / (double)gfxPlatform::GetSoftwareVsyncRate();
mVsyncRate = mozilla::TimeDuration::FromMilliseconds(rate);
mVsyncThread = new base::Thread("SoftwareVsyncThread");
MOZ_RELEASE_ASSERT(mVsyncThread->Start(),
"GFX: Could not start software vsync thread");
}
SoftwareDisplay::~SoftwareDisplay() = default;
void SoftwareDisplay::EnableVsync() {
MOZ_ASSERT(mVsyncThread->IsRunning());
if (NS_IsMainThread()) {
if (mVsyncEnabled) {
return;
}
mVsyncEnabled = true;
mVsyncThread->message_loop()->PostTask(NewRunnableMethod(
"SoftwareDisplay::EnableVsync", this, &SoftwareDisplay::EnableVsync));
return;
}
MOZ_ASSERT(IsInSoftwareVsyncThread());
TimeStamp vsyncTime = TimeStamp::Now();
TimeStamp outputTime = vsyncTime + mVsyncRate;
NotifyVsync(vsyncTime, outputTime);
}
void SoftwareDisplay::DisableVsync() {
MOZ_ASSERT(mVsyncThread->IsRunning());
if (NS_IsMainThread()) {
if (!mVsyncEnabled) {
return;
}
mVsyncEnabled = false;
mVsyncThread->message_loop()->PostTask(NewRunnableMethod(
"SoftwareDisplay::DisableVsync", this, &SoftwareDisplay::DisableVsync));
return;
}
MOZ_ASSERT(IsInSoftwareVsyncThread());
if (mCurrentVsyncTask) {
mCurrentVsyncTask->Cancel();
mCurrentVsyncTask = nullptr;
}
}
bool SoftwareDisplay::IsVsyncEnabled() {
MOZ_ASSERT(NS_IsMainThread());
return mVsyncEnabled;
}
bool SoftwareDisplay::IsInSoftwareVsyncThread() {
return mVsyncThread->thread_id() == PlatformThread::CurrentId();
}
void SoftwareDisplay::NotifyVsync(const mozilla::TimeStamp& aVsyncTimestamp,
const mozilla::TimeStamp& aOutputTimestamp) {
MOZ_ASSERT(IsInSoftwareVsyncThread());
mozilla::TimeStamp displayVsyncTime = aVsyncTimestamp;
mozilla::TimeStamp now = mozilla::TimeStamp::Now();
// Posted tasks can only have integer millisecond delays
// whereas TimeDurations can have floating point delays.
// Thus the vsync timestamp can be in the future, which large parts
// of the system can't handle, including animations. Force the timestamp to be
// now.
if (aVsyncTimestamp > now) {
displayVsyncTime = now;
}
Display::NotifyVsync(displayVsyncTime, aOutputTimestamp);
// Prevent skew by still scheduling based on the original
// vsync timestamp
ScheduleNextVsync(aVsyncTimestamp);
}
mozilla::TimeDuration SoftwareDisplay::GetVsyncRate() { return mVsyncRate; }
void SoftwareDisplay::ScheduleNextVsync(mozilla::TimeStamp aVsyncTimestamp) {
MOZ_ASSERT(IsInSoftwareVsyncThread());
mozilla::TimeStamp nextVsync = aVsyncTimestamp + mVsyncRate;
mozilla::TimeDuration delay = nextVsync - mozilla::TimeStamp::Now();
if (delay.ToMilliseconds() < 0) {
delay = mozilla::TimeDuration::FromMilliseconds(0);
nextVsync = mozilla::TimeStamp::Now();
}
TimeStamp outputTime = nextVsync + mVsyncRate;
mCurrentVsyncTask =
NewCancelableRunnableMethod<mozilla::TimeStamp, mozilla::TimeStamp>(
"SoftwareDisplay::NotifyVsync", this, &SoftwareDisplay::NotifyVsync,
nextVsync, outputTime);
RefPtr<Runnable> addrefedTask = mCurrentVsyncTask;
mVsyncThread->message_loop()->PostDelayedTask(addrefedTask.forget(),
delay.ToMilliseconds());
}
void SoftwareDisplay::Shutdown() {
MOZ_ASSERT(NS_IsMainThread());
DisableVsync();
mVsyncThread->Stop();
delete mVsyncThread;
}
|