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
|
// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "cc/output/begin_frame_args.h"
#include "ui/gfx/frame_time.h"
namespace cc {
BeginFrameArgs::BeginFrameArgs()
: frame_time(base::TimeTicks()),
deadline(base::TimeTicks()),
interval(base::TimeDelta::FromMicroseconds(-1)) {
}
BeginFrameArgs::BeginFrameArgs(base::TimeTicks frame_time,
base::TimeTicks deadline,
base::TimeDelta interval)
: frame_time(frame_time),
deadline(deadline),
interval(interval)
{}
BeginFrameArgs BeginFrameArgs::Create(base::TimeTicks frame_time,
base::TimeTicks deadline,
base::TimeDelta interval) {
return BeginFrameArgs(frame_time, deadline, interval);
}
BeginFrameArgs BeginFrameArgs::CreateForSynchronousCompositor() {
// For WebView/SynchronousCompositor, we always want to draw immediately,
// so we set the deadline to 0 and guess that the interval is 16 milliseconds.
return BeginFrameArgs(gfx::FrameTime::Now(),
base::TimeTicks(),
DefaultInterval());
}
BeginFrameArgs BeginFrameArgs::CreateForTesting() {
base::TimeTicks now = gfx::FrameTime::Now();
return BeginFrameArgs(now,
now + (DefaultInterval() / 2),
DefaultInterval());
}
BeginFrameArgs BeginFrameArgs::CreateExpiredForTesting() {
base::TimeTicks now = gfx::FrameTime::Now();
return BeginFrameArgs(now,
now - DefaultInterval(),
DefaultInterval());
}
// This is a hard-coded deadline adjustment that assumes 60Hz, to be used in
// cases where a good estimated draw time is not known. Using 1/3 of the vsync
// as the default adjustment gives the Browser the last 1/3 of a frame to
// produce output, the Renderer Impl thread the middle 1/3 of a frame to produce
// ouput, and the Renderer Main thread the first 1/3 of a frame to produce
// output.
base::TimeDelta BeginFrameArgs::DefaultDeadlineAdjustment() {
return base::TimeDelta::FromMicroseconds(-16666 / 3);
}
base::TimeDelta BeginFrameArgs::DefaultInterval() {
return base::TimeDelta::FromMicroseconds(16666);
}
base::TimeDelta BeginFrameArgs::DefaultRetroactiveBeginFramePeriod() {
return base::TimeDelta::FromMicroseconds(4444);
}
} // namespace cc
|
