//-*****************************************************************************
void GetRelevantSampleTimes( ProcArgs &args, TimeSamplingPtr timeSampling,
size_t numSamples, SampleTimeSet &output )
{
if ( numSamples < 2 )
{
output.insert( 0.0 );
return;
}
chrono_t frameTime = args.frame / args.fps;
chrono_t shutterOpenTime = ( args.frame + args.shutterOpen ) / args.fps;
chrono_t shutterCloseTime = ( args.frame + args.shutterClose ) / args.fps;
std::pair<index_t, chrono_t> shutterOpenFloor =
timeSampling->getFloorIndex( shutterOpenTime, numSamples );
std::pair<index_t, chrono_t> shutterCloseCeil =
timeSampling->getCeilIndex( shutterCloseTime, numSamples );
//TODO, what's a reasonable episilon?
static const chrono_t epsilon = 1.0 / 10000.0;
//check to see if our second sample is really the
//floor that we want due to floating point slop
//first make sure that we have at least two samples to work with
if ( shutterOpenFloor.first < shutterCloseCeil.first )
{
//if our open sample is less than open time,
//look at the next index time
if ( shutterOpenFloor.second < shutterOpenTime )
{
chrono_t nextSampleTime =
timeSampling->getSampleTime( shutterOpenFloor.first + 1 );
if ( fabs( nextSampleTime - shutterOpenTime ) < epsilon )
{
shutterOpenFloor.first += 1;
shutterOpenFloor.second = nextSampleTime;
}
}
}
for ( index_t i = shutterOpenFloor.first; i < shutterCloseCeil.first; ++i )
{
output.insert( timeSampling->getSampleTime( i ) );
}
//no samples above? put frame time in there and get out
if ( output.size() == 0 )
{
output.insert( frameTime );
return;
}
chrono_t lastSample = *(output.rbegin() );
//determine whether we need the extra sample at the end
if ( ( fabs( lastSample - shutterCloseTime ) > epsilon )
&& lastSample < shutterCloseTime )
{
output.insert( shutterCloseCeil.second );
}
}
