/// <summary>
/// Simple calculation of time base for the transfer assuming both are in circular orbit
/// </summary>
private void ComputeBaseTransferTime()
{
double xferOrbit = 0.5 * (shipRadius + moonRadius) / ge.GetPhysicalScale();
double planetMass = ge.GetMass(planet);
timeHohmann = Mathd.PI * Mathd.Sqrt(xferOrbit * xferOrbit * xferOrbit / planetMass);
}
// IFixedOrbit
public void PreEvolve(float physicalScale, float massScale)
{
CalculateRotation();
GravityEngine ge = GravityEngine.Instance();
float a_phy = a_scaled / ge.GetPhysicalScale();
mu = (float)GravityEngine.Instance().GetMass(centerNbody);
orbit_period = Mathf.Sqrt(a_phy * a_phy * a_phy / mu); // G=1
// nu to anomoly (vallado algorithm 5, p77) It *really* is sin not sinh inside.
float sinh_H = Mathf.Sin(phase_nu) * Mathf.Sqrt(ecc * ecc - 1) / (1 + ecc * Mathf.Cos(phase_nu));
// ArcSinh(x) = ln(x + sqrt(x^2+1) )
float H = Mathf.Log(sinh_H + Mathf.Sqrt(sinh_H * sinh_H + 1));
mean_anomoly_phase = ecc * sinh_H - H;
// Debug.LogFormat("PreEvolve: M0={0} H={1} nu0={1}", mean_anomoly_phase, H, nu);
}
public float GetPeriod()
{
if (centerNbody == null)
{
return(0);
}
// Use Find to allow Editor to use method.
if (gravityEngine == null)
{
gravityEngine = (GravityEngine)FindObjectOfType(typeof(GravityEngine));
if (gravityEngine == null)
{
Debug.LogError("Need GravityEngine in the scene");
return(0);
}
base.Init();
}
a_phy = a_scaled / gravityEngine.GetPhysicalScale();
float massScale = gravityEngine.massScale;
orbitPeriod = 2f * Mathf.PI * Mathf.Sqrt(a_phy * a_phy * a_phy / ((float)centerNbody.mass * massScale)); // G=1
return(orbitPeriod);
}