public double DEC_degrees_to(MechanicalPoint b)
{
Contract.Requires(!(b is null));
// RA is circular, DEC is not
return((b._DECm - _DECm) / 3600.0);
}
public static double Subtract(MechanicalPoint a, MechanicalPoint b)
{
Contract.Requires(!(a is null));
Contract.Requires(!(b is null));
double ra_distance = a.RA_degrees_to(b);
double dec_distance = a.DEC_degrees_to(b);
// FIXME: Incorrect distance calculation, but enough for our purpose
return(Math.Sqrt(ra_distance * ra_distance + dec_distance * dec_distance));
}
public double RA_degrees_to(MechanicalPoint b)
{
Contract.Requires(!(b is null));
// RA is circular, DEC is not
// We have hours and not degrees because that's what the mount is handling in terms of precision
// We need to be cautious, as if we were to use real degrees, the RA movement would need to be 15 times more precise
long delta = b._RAm - _RAm;
if (delta > +12 * 3600)
{
delta -= 24 * 3600;
}
if (delta < -12 * 3600)
{
delta += 24 * 3600;
}
return((double)(delta * 15) / 3600.0);
}
