void
task(void)
{
// Return if task is not active.
if (!isActive())
return;
double slat, slon, dx, dy, dz;
slat = m_last_state.lat;
slon = m_last_state.lon;
// get absolute (simulated) position
WGS84::displace(m_last_state.x, m_last_state.y, &slat, &slon);
// compute offset from plume peak
WGS84::displacement(slat, slon, 0, m_args.peak_lat, m_args.peak_lon, 0, &dx, &dy, &dz);
// calculate value based on 2d gaussian function
double expn = exp(-1 * ((dx * dx + dy * dy)
/(2 * m_args.peak_width * m_args.peak_width)));
double val = m_args.away_val + (m_args.peak_val - m_args.away_val) * expn;
val += m_prng->gaussian() * m_args.std_dev;
m_msg->setValueFP(val);
dispatch(m_msg);
}
