1 // Copyright 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "cc/output/begin_frame_args.h"
6 #include "ui/gfx/frame_time.h"
7
8 namespace cc {
9
BeginFrameArgs()10 BeginFrameArgs::BeginFrameArgs()
11 : frame_time(base::TimeTicks()),
12 deadline(base::TimeTicks()),
13 interval(base::TimeDelta::FromMicroseconds(-1)) {
14 }
15
BeginFrameArgs(base::TimeTicks frame_time,base::TimeTicks deadline,base::TimeDelta interval)16 BeginFrameArgs::BeginFrameArgs(base::TimeTicks frame_time,
17 base::TimeTicks deadline,
18 base::TimeDelta interval)
19 : frame_time(frame_time),
20 deadline(deadline),
21 interval(interval)
22 {}
23
Create(base::TimeTicks frame_time,base::TimeTicks deadline,base::TimeDelta interval)24 BeginFrameArgs BeginFrameArgs::Create(base::TimeTicks frame_time,
25 base::TimeTicks deadline,
26 base::TimeDelta interval) {
27 return BeginFrameArgs(frame_time, deadline, interval);
28 }
29
CreateForSynchronousCompositor()30 BeginFrameArgs BeginFrameArgs::CreateForSynchronousCompositor() {
31 // For WebView/SynchronousCompositor, we always want to draw immediately,
32 // so we set the deadline to 0 and guess that the interval is 16 milliseconds.
33 return BeginFrameArgs(gfx::FrameTime::Now(),
34 base::TimeTicks(),
35 DefaultInterval());
36 }
37
CreateForTesting()38 BeginFrameArgs BeginFrameArgs::CreateForTesting() {
39 base::TimeTicks now = gfx::FrameTime::Now();
40 return BeginFrameArgs(now,
41 now + (DefaultInterval() / 2),
42 DefaultInterval());
43 }
44
CreateExpiredForTesting()45 BeginFrameArgs BeginFrameArgs::CreateExpiredForTesting() {
46 base::TimeTicks now = gfx::FrameTime::Now();
47 return BeginFrameArgs(now,
48 now - DefaultInterval(),
49 DefaultInterval());
50 }
51
52 // This is a hard-coded deadline adjustment that assumes 60Hz, to be used in
53 // cases where a good estimated draw time is not known. Using 1/3 of the vsync
54 // as the default adjustment gives the Browser the last 1/3 of a frame to
55 // produce output, the Renderer Impl thread the middle 1/3 of a frame to produce
56 // ouput, and the Renderer Main thread the first 1/3 of a frame to produce
57 // output.
DefaultDeadlineAdjustment()58 base::TimeDelta BeginFrameArgs::DefaultDeadlineAdjustment() {
59 return base::TimeDelta::FromMicroseconds(-16666 / 3);
60 }
61
DefaultInterval()62 base::TimeDelta BeginFrameArgs::DefaultInterval() {
63 return base::TimeDelta::FromMicroseconds(16666);
64 }
65
DefaultRetroactiveBeginFramePeriod()66 base::TimeDelta BeginFrameArgs::DefaultRetroactiveBeginFramePeriod() {
67 return base::TimeDelta::FromMicroseconds(4444);
68 }
69
70 } // namespace cc
71