public static double GalAtPosition(Vessel vessel)
{
GravityMap LocalMap = ThisGravityMap(vessel.orbitDriver.orbit.referenceBody.GetName());
double meanGal = LocalMap.meanGal;
Mascon MasCon = LocalMasCon(vessel);
double CentreGal = MasCon.centreGal;
double CentreLat = MasCon.centreLat;
double CentreLong = MasCon.centreLong;
double radiusdeg = MasCon.diamdeg / 2;
double EdgeLat = CentreLat + radiusdeg;
double EdgeLong = CentreLong + radiusdeg;
double GalAtDistance = 0.0;
double R = vessel.orbitDriver.orbit.referenceBody.Radius;
double A = ToRadians(CentreLat);
double B = ToRadians(EdgeLat);
double C = ToRadians(EdgeLat) - ToRadians(CentreLat);
double D = ToRadians(EdgeLong) - ToRadians(CentreLong);
double E = Math.Sin(C / 2) * Math.Sin(C / 2) +
Math.Cos(A) * Math.Cos(B) *
Math.Sin(D / 2) * Math.Sin(D / 2);
double F = 2 * Math.Atan2(Math.Sqrt(E), Math.Sqrt(1 - E));
double Edgedistance = R * F;
double φ1 = ToRadians(CentreLat);
double φ2 = ToRadians(vessel.latitude);
double Δφ = ToRadians(vessel.latitude) - ToRadians(CentreLat);
double Δλ = ToRadians(vessel.longitude) - ToRadians(CentreLong);
double a = Math.Sin(Δφ / 2) * Math.Sin(Δφ / 2) +
Math.Cos(φ1) * Math.Cos(φ2) *
Math.Sin(Δλ / 2) * Math.Sin(Δλ / 2);
double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a));
double Vesseldistance = R * c;
GalAtDistance = Math.Abs(CentreGal) / Edgedistance * Vesseldistance; // Work out negative push mascons for 1.6.0 removed absolute CentreGal
/*
* double GravitationalConstant = 6.67408 * Math.Pow(10.0, -11.0); // G [Newton Meter Squared per Square Kilograms]
* double AccelerationToGal = 100.0;
* double GalAtSurface = ((GravitationalConstant * vessel.orbitDriver.orbit.referenceBody.Mass * vessel.GetCorrectVesselMass()));
* double GalAtVerticalDistance = ((GravitationalConstant * vessel.orbitDriver.orbit.referenceBody.Mass * vessel.GetCorrectVesselMass()) / (Math.Pow(vessel.orbitDriver.orbit.altitude,2.0))) * AccelerationToGal;
* GalAtDistance = GalAtDistance + GalAtVerticalDistance;
*/
return(GalAtDistance);
}
internal static Mascon LocalMasCon(Vessel vessel)
{
GravityMap LocalGravityMap = ThisGravityMap(vessel.orbitDriver.orbit.referenceBody.GetName());
Mascon Local = new Mascon();
if (LocalGravityMap.masconAr.Count() > 0)
{
double VesselLat = vessel.latitude;
double VesselLong = vessel.longitude;
bool LatitudeWithin = false;
bool LongitudeWithin = false;
foreach (Mascon MasCon in LocalGravityMap.masconAr)
{
int idx = MasCon.id;
double CentreGal = MasCon.centreGal;
double CentreLat = MasCon.centreLat;
double CentreLong = MasCon.centreLong;
double DegDiam = MasCon.diamdeg;
double DegRad = DegDiam / 2.0;
double UpperBoundLat = CentreLat + DegRad;
double LowerBoundLat = CentreLat - DegRad;
double UpperBoundLong = CentreLong + DegRad;
double LowerBoundLong = CentreLong - DegRad;
if (UpperBoundLat > 90)
{
UpperBoundLat = Math.Abs(UpperBoundLat - 180);
}
if (LowerBoundLat < 90)
{
LowerBoundLat = -1 * (UpperBoundLat + 180);
}
if (UpperBoundLong > 180)
{
UpperBoundLong = UpperBoundLong - 360;
}
if (LowerBoundLong < -180)
{
LowerBoundLong = LowerBoundLong + 360;
}
if (IsBetween(VesselLat, UpperBoundLat, LowerBoundLat))
{
LatitudeWithin = true;
}
if (IsBetween(VesselLong, UpperBoundLong, LowerBoundLong))
{
LongitudeWithin = true;
}
if (LatitudeWithin && LongitudeWithin)
{
Local = MasCon;
break;
}
}
}
return(Local);
}
