elapsedtime.cxx

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#include <sal/config.h>
 
#include <canvas/elapsedtime.hxx>
 
#include <tools/time.hxx>
#include <utility>
 
namespace canvas::tools {
 
double ElapsedTime::getSystemTime()
{
    return ::tools::Time::GetMonotonicTicks() / 1.0E6;
}
 
ElapsedTime::ElapsedTime()
    : m_pTimeBase(),
      m_fLastQueriedTime( 0.0 ),
      m_fStartTime( getSystemTime() ),
      m_fFrozenTime( 0.0 ),
      m_bInPauseMode( false ),
      m_bInHoldMode( false )
{
}
 
ElapsedTime::ElapsedTime(
    std::shared_ptr<ElapsedTime> pTimeBase )
    : m_pTimeBase(std::move( pTimeBase )),
      m_fLastQueriedTime( 0.0 ),
      m_fStartTime( getCurrentTime() ),
      m_fFrozenTime( 0.0 ),
      m_bInPauseMode( false ),
      m_bInHoldMode( false )
{
}
 
void ElapsedTime::reset()
{
    m_fLastQueriedTime = 0.0;
    m_fStartTime = getCurrentTime();
    m_fFrozenTime = 0.0;
    m_bInPauseMode = false;
    m_bInHoldMode = false;
}
 
void ElapsedTime::adjustTimer( double fOffset )
{
    // to make getElapsedTime() become _larger_, have to reduce
    // m_fStartTime.
    m_fStartTime -= fOffset;
 
    // also adjust frozen time, this method must _always_ affect the
    // value returned by getElapsedTime()!
    if (m_bInHoldMode || m_bInPauseMode)
        m_fFrozenTime += fOffset;
}
 
double ElapsedTime::getCurrentTime() const
{
    return m_pTimeBase == nullptr ? getSystemTime() : m_pTimeBase->getElapsedTimeImpl();
}
 
double ElapsedTime::getElapsedTime() const
{
    m_fLastQueriedTime = getElapsedTimeImpl();
    return m_fLastQueriedTime;
}
 
double ElapsedTime::getElapsedTimeImpl() const
{
    if (m_bInHoldMode || m_bInPauseMode)
        return m_fFrozenTime;
 
    return getCurrentTime() - m_fStartTime;
}
 
void ElapsedTime::pauseTimer()
{
    m_fFrozenTime = getElapsedTimeImpl();
    m_bInPauseMode = true;
}
 
void ElapsedTime::continueTimer()
{
    m_bInPauseMode = false;
 
    // stop pausing, time runs again. Note that
    // getElapsedTimeImpl() honors hold mode, i.e. a
    // continueTimer() in hold mode will preserve the latter
    const double fPauseDuration( getElapsedTimeImpl() - m_fFrozenTime );
 
    // adjust start time, such that subsequent getElapsedTime() calls
    // will virtually start from m_fFrozenTime.
    m_fStartTime += fPauseDuration;
}
 
void ElapsedTime::holdTimer()
{
    // when called during hold mode (e.g. more than once per time
    // object), the original hold time will be maintained.
    m_fFrozenTime = getElapsedTimeImpl();
    m_bInHoldMode = true;
}
 
void ElapsedTime::releaseTimer()
{
    m_bInHoldMode = false;
}
 
} // namespace
 
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