Orbits and PatchedConicsOrbit methods and info

When porting from KSP1 to KSP2, one of the first things you're likely to encounter is the fact that where KSP1 defined an orbit using the Orbit class, in KSP2 it's now the PatchedConicsOrbit class. These classes have a lot in common; for example, there are a number of methods and properties where the names are almost identical other than a change of case for the initial character. Nevertheless, there are a few differences that you should know about when porting KSP1 code to work in KSP2.

So where you might have a variable of type Orbit, now you'll mostly use a variable of type PatchedConicsOrbit.

KSP1	KSP2
`Orbit o;`	`PatchedConicsOrbit o;`
`o.referenceBody.position`	`o.referenceBody.Position.localPosition`
`o.referenceBody.transform.up`	`o.referenceBody.transform.up.vector`
`o.referenceBody.transform.right`	`o.referenceBody.transform.right.vector`
`o.referenceBody.Radius`	`o.referenceBody.radius`
`o.referenceBody.orbit`	`o.referenceBody.Orbit`
`o.LAN`	`o.longitudeOfAscendingNode`
`Planetarium.up`	`o.ReferenceFrame.up.vector`
`Planetarium.right`	`o.ReferenceFrame.right.vector`
`o.PeR`	`o.Periapsis`
`o.PeA`	`o.PeriapsisArl`
`o.ApR`	`o.Apoapsis`
`o.ApA`	`o.ApoapsisArl`
`o.trueAnomaly`	`o.TrueAnomaly`
`o.patchEndTransition`	`o.PatchEndTransition`
`o.referenceBody.timeWarpAltitudeLimits [n]`	`o.referenceBody.TimeWarpAltitudeOffset*n`

KSP1	KSP2
`o.getOrbitalVelocityAtUT()`	`o.GetOrbitalVelocityAtUTZup()`
`o.getRelativePositionAtUT()`	`o.GetRelativePositionAtUT()`
`o.GetOrbitNormal()`	`o.GetRelativeOrbitNormal()`
`o.referenceBody.GetLatitude()`	`o.referenceBody.GetLatLonAltFromRadius()`

Body Type: Properties and Methods

TypeCelestialBody -> CelestialBodyComponent

Vessel Type: Properties and Methods

Coordinate Systems

Useful Code Block Conversions

Was

o.GetOrbitalStateVectorsAtUT(UT, out pos, out vel);

newOrbit.UpdateFromStateVectors(pos, vel, o.referenceBody, UT);

o.GetOrbitalStateVectorsAtUT(UT, out pos, out vel);

KSP.Sim.Position position = new KSP.Sim.Position(o.referenceBody.coordinateSystem, OrbitExtensions.SwapYZ(pos - o.referenceBody.Position.localPosition));

KSP.Sim.Velocity velocity = new KSP.Sim.Velocity(o.referenceBody.relativeToMotion, OrbitExtensions.SwapYZ(vel));

newOrbit.UpdateFromStateVectors(position, velocity, o.referenceBody, UT);

Was

PatchedConics.SolverParameters solverParameters = new PatchedConics.SolverParameters();

PatchedConicSolver.SolverParameters solverParameters = new PatchedConicSolver.SolverParameters();

Was

PatchedConics.CalculatePatch(o, nextOrbit, UT, solverParameters, null);

nextOrbit = o.NextPatch as PatchedConicsOrbit;

Was

o.UTAtMeanAnomaly(o.GetMeanAnomalyAtEccentricAnomaly(o.GetEccentricAnomalyAtTrueAnomaly(trueAnomaly)), UT);

o.GetUTforTrueAnomaly(trueAnomaly*UtilMath.Deg2Rad, o.period);

New Code

public static Vector3d DvToBurnVec(PatchedConicsOrbit o, Vector3d dV, double UT)

{

Vector3d burnVec;

burnVec.x = Vector3d.Dot(dV, o.RadialPlus(UT));

burnVec.y = Vector3d.Dot(dV, o.NormalPlus(UT));

burnVec.z = Vector3d.Dot(dV, -1 * o.Prograde(UT)); return burnVec;

}

public static Vector3d BurnVecToDv(PatchedConicsOrbit o, Vector3d burnVec, double UT) { return burnVec.x * o.RadialPlus(UT) + burnVec.y * o.NormalPlus(UT) - burnVec.z * o.Prograde(UT); }