1/*
2 * Copyright (C) 2010 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27
28#if USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR)
29
30#include "DisplayRefreshMonitor.h"
31
32#include <QuartzCore/QuartzCore.h>
33#include <wtf/CurrentTime.h>
34#include <wtf/MainThread.h>
35
36namespace WebCore {
37
38static CVReturn displayLinkCallback(CVDisplayLinkRef, const CVTimeStamp* now, const CVTimeStamp* outputTime, CVOptionFlags, CVOptionFlags*, void* data)
39{
40    DisplayRefreshMonitor* monitor = static_cast<DisplayRefreshMonitor*>(data);
41
42    double nowSeconds = static_cast<double>(now->videoTime) / static_cast<double>(now->videoTimeScale);
43    double outputTimeSeconds = static_cast<double>(outputTime->videoTime) / static_cast<double>(outputTime->videoTimeScale);
44    monitor->displayLinkFired(nowSeconds, outputTimeSeconds);
45
46    return kCVReturnSuccess;
47}
48
49DisplayRefreshMonitor::~DisplayRefreshMonitor()
50{
51    if (m_displayLink) {
52        CVDisplayLinkStop(m_displayLink);
53        CVDisplayLinkRelease(m_displayLink);
54        m_displayLink = 0;
55    }
56
57    cancelCallOnMainThread(DisplayRefreshMonitor::handleDisplayRefreshedNotificationOnMainThread, this);
58}
59
60bool DisplayRefreshMonitor::requestRefreshCallback()
61{
62    if (!m_active)
63        return false;
64
65    if (!m_displayLink) {
66        m_active = false;
67        CVReturn error = CVDisplayLinkCreateWithCGDisplay(m_displayID, &m_displayLink);
68        if (error)
69            return false;
70
71        error = CVDisplayLinkSetOutputCallback(m_displayLink, displayLinkCallback, this);
72        if (error)
73            return false;
74
75        error = CVDisplayLinkStart(m_displayLink);
76        if (error)
77            return false;
78
79        m_active = true;
80    }
81
82    MutexLocker lock(m_mutex);
83    m_scheduled = true;
84    return true;
85}
86
87void DisplayRefreshMonitor::displayLinkFired(double nowSeconds, double outputTimeSeconds)
88{
89    MutexLocker lock(m_mutex);
90    if (!m_previousFrameDone)
91        return;
92
93    m_previousFrameDone = false;
94
95    double webKitMonotonicNow = monotonicallyIncreasingTime();
96    double timeUntilOutput = outputTimeSeconds - nowSeconds;
97    // FIXME: Should this be using webKitMonotonicNow?
98    m_monotonicAnimationStartTime = webKitMonotonicNow + timeUntilOutput;
99
100    callOnMainThread(handleDisplayRefreshedNotificationOnMainThread, this);
101}
102
103}
104
105#endif // USE(REQUEST_ANIMATION_FRAME_DISPLAY_MONITOR)
106