public static AgcTuple nodeVector(double inc, string direction)
{
var b = Math.Tan(90 - inc) *
Math.Tan(Globals.KrpConnection.SpaceCenter().ActiveVessel.Flight().Latitude);
b = Math.Asin(Math.Min(Math.Max(-1, b), 1));
var yVec = new AgcTuple(0, 1, 0);
var longitudeVector = AgcMath.map(
yVec,
AgcMath.normalize(Globals.KrpConnection.SpaceCenter().ActiveVessel.Orbit.Body.Position(
Globals.KrpConnection.SpaceCenter().ActiveVessel.ReferenceFrame
))
);
switch (direction)
{
case "north":
return(rodrigues(longitudeVector, yVec, b));
case "south":
return(rodrigues(longitudeVector, yVec, 180 - b));
default:
return(nodeVector(inc, "north"));
}
}
public static AgcTuple rodrigues(AgcTuple inVector, AgcTuple axis, double angle)
{
axis = AgcMath.normalize(axis);
var outVector = inVector * Math.Cos(angle);
outVector += AgcMath.cross(axis, inVector) * Math.Sin(angle);
outVector += axis * AgcMath.dot(axis, inVector) * (1 - Math.Cos(angle));
return(outVector);
}
public static AgcTuple solarPrimeVector(ReferenceFrame referenceFrame)
{
var sun = Globals.KrpConnection.SpaceCenter().Bodies["Sun"];
var secondsPerDegree = sun.RotationalPeriod / 360;
var rotationOffset = (Globals.KrpConnection.SpaceCenter().UT / secondsPerDegree) % 360;
AgcTuple sunPosition = sun.Position(referenceFrame);
AgcTuple sunPosition2 = sun.SurfacePosition(0, 0 - rotationOffset, referenceFrame);
var primeVector = sunPosition2 - sunPosition;
return(AgcMath.normalize(primeVector));
}