canvas/source/tools/elapsedtime.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <sal/config.h>
  21
  22 #include <canvas/elapsedtime.hxx>
  23
  24 #include <tools/time.hxx>
  25
  26 namespace canvas::tools {
  27
  28 double ElapsedTime::getSystemTime()
  29 {
  30     return ::tools::Time::GetMonotonicTicks() / 1.0E6;
  31 }
  32
  33 ElapsedTime::ElapsedTime()
  34     : m_pTimeBase(),
  35       m_fLastQueriedTime( 0.0 ),
  36       m_fStartTime( getSystemTime() ),
  37       m_fFrozenTime( 0.0 ),
  38       m_bInPauseMode( false ),
  39       m_bInHoldMode( false )
  40 {
  41 }
  42
  43 ElapsedTime::ElapsedTime(
  44     std::shared_ptr<ElapsedTime> const & pTimeBase )
  45     : m_pTimeBase( pTimeBase ),
  46       m_fLastQueriedTime( 0.0 ),
  47       m_fStartTime( getCurrentTime() ),
  48       m_fFrozenTime( 0.0 ),
  49       m_bInPauseMode( false ),
  50       m_bInHoldMode( false )
  51 {
  52 }
  53
  54 void ElapsedTime::reset()
  55 {
  56     m_fLastQueriedTime = 0.0;
  57     m_fStartTime = getCurrentTime();
  58     m_fFrozenTime = 0.0;
  59     m_bInPauseMode = false;
  60     m_bInHoldMode = false;
  61 }
  62
  63 void ElapsedTime::adjustTimer( double fOffset )
  64 {
  65     // to make getElapsedTime() become _larger_, have to reduce
  66     // m_fStartTime.
  67     m_fStartTime -= fOffset;
  68
  69     // also adjust frozen time, this method must _always_ affect the
  70     // value returned by getElapsedTime()!
  71     if (m_bInHoldMode || m_bInPauseMode)
  72         m_fFrozenTime += fOffset;
  73 }
  74
  75 double ElapsedTime::getCurrentTime() const
  76 {
  77     return m_pTimeBase == nullptr ? getSystemTime() : m_pTimeBase->getElapsedTimeImpl();
  78 }
  79
  80 double ElapsedTime::getElapsedTime() const
  81 {
  82     m_fLastQueriedTime = getElapsedTimeImpl();
  83     return m_fLastQueriedTime;
  84 }
  85
  86 double ElapsedTime::getElapsedTimeImpl() const
  87 {
  88     if (m_bInHoldMode || m_bInPauseMode)
  89         return m_fFrozenTime;
  90
  91     return getCurrentTime() - m_fStartTime;
  92 }
  93
  94 void ElapsedTime::pauseTimer()
  95 {
  96     m_fFrozenTime = getElapsedTimeImpl();
  97     m_bInPauseMode = true;
  98 }
  99
 100 void ElapsedTime::continueTimer()
 101 {
 102     m_bInPauseMode = false;
 103
 104     // stop pausing, time runs again. Note that
 105     // getElapsedTimeImpl() honors hold mode, i.e. a
 106     // continueTimer() in hold mode will preserve the latter
 107     const double fPauseDuration( getElapsedTimeImpl() - m_fFrozenTime );
 108
 109     // adjust start time, such that subsequent getElapsedTime() calls
 110     // will virtually start from m_fFrozenTime.
 111     m_fStartTime += fPauseDuration;
 112 }
 113
 114 void ElapsedTime::holdTimer()
 115 {
 116     // when called during hold mode (e.g. more than once per time
 117     // object), the original hold time will be maintained.
 118     m_fFrozenTime = getElapsedTimeImpl();
 119     m_bInHoldMode = true;
 120 }
 121
 122 void ElapsedTime::releaseTimer()
 123 {
 124     m_bInHoldMode = false;
 125 }
 126
 127 } // namespace
 128
 129 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */