1 /* 2 * Copyright (C) 2011 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 COMPUTER, 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 #include "platform/Clock.h" 28 29 #include "wtf/CurrentTime.h" 30 31 namespace WebCore { 32 33 Clock::Clock() 34 : m_running(false) 35 , m_rate(1) 36 , m_offset(0) 37 { 38 m_startTime = m_lastTime = now(); 39 } 40 41 void Clock::setCurrentTime(double time) 42 { 43 m_startTime = m_lastTime = now(); 44 m_offset = time; 45 } 46 47 double Clock::currentTime() const 48 { 49 return currentDelta() + m_offset; 50 } 51 52 void Clock::setPlayRate(double rate) 53 { 54 m_offset += currentDelta(); 55 m_lastTime = m_startTime = now(); 56 m_rate = rate; 57 } 58 59 void Clock::start() 60 { 61 if (m_running) 62 return; 63 64 m_lastTime = m_startTime = now(); 65 m_running = true; 66 } 67 68 void Clock::stop() 69 { 70 if (!m_running) 71 return; 72 73 m_offset += currentDelta(); 74 m_lastTime = m_startTime = now(); 75 m_running = false; 76 } 77 78 double Clock::now() const 79 { 80 return WTF::currentTime(); 81 } 82 83 double Clock::currentDelta() const 84 { 85 if (m_running) 86 m_lastTime = now(); 87 return (m_lastTime - m_startTime) * m_rate; 88 } 89 90 PassOwnPtr<Clock> Clock::create() 91 { 92 return adoptPtr(new Clock()); 93 } 94 95 } // namespace WebCore 96