/// <summary>
/// Creates on Orbit at current location from a given velocity
/// </summary>
/// <returns>The Orbit Does not attach the OrbitDB to the entity!</returns>
/// <param name="parent">Parent.</param>
/// <param name="entity">Entity.</param>
/// <param name="velocityAU">Velocity.</param>
public static OrbitDB FromVector(Entity parent, Entity entity, Vector3 velocityAU, DateTime atDateTime)
{
var parentMass = parent.GetDataBlob <MassVolumeDB>().Mass;
var myMass = entity.GetDataBlob <MassVolumeDB>().Mass;
var epoch1 = parent.Manager.ManagerSubpulses.StarSysDateTime; //getting epoch from here is incorrect as the local datetime doesn't change till after the subpulse.
var parentPos = OrbitProcessor.GetAbsolutePosition_AU(parent.GetDataBlob <OrbitDB>(), atDateTime); //need to use the parent position at the epoch
var posdb = entity.GetDataBlob <PositionDB>();
posdb.SetParent(parent);
var ralitivePos = posdb.RelativePosition_AU;//entity.GetDataBlob<PositionDB>().AbsolutePosition_AU - parentPos;
if (ralitivePos.Length() > OrbitProcessor.GetSOI(parent))
{
throw new Exception("Entity not in target SOI");
}
var sgp = GameConstants.Science.GravitationalConstant * (myMass + parentMass) / 3.347928976e33;
var ke = OrbitMath.KeplerFromPositionAndVelocity(sgp, ralitivePos, velocityAU, atDateTime);
var epoch = atDateTime;// - TimeSpan.FromSeconds(ke.Epoch); //ke.Epoch is seconds from periapsis.
OrbitDB orbit = new OrbitDB(parent, parentMass, myMass,
Math.Abs(ke.SemiMajorAxis),
ke.Eccentricity,
Angle.ToDegrees(ke.Inclination),
Angle.ToDegrees(ke.LoAN),
Angle.ToDegrees(ke.AoP),
Angle.ToDegrees(ke.MeanAnomalyAtEpoch),
epoch);
var pos = OrbitProcessor.GetPosition_AU(orbit, atDateTime);
var d = Distance.AuToKm(pos - ralitivePos).Length();
if (d > 1)
{
var e = new Event(atDateTime, "Positional difference of " + d + "Km when creating orbit from velocity");
e.Entity = entity;
e.SystemGuid = entity.Manager.ManagerGuid;
e.EventType = EventType.Opps;
//e.Faction = entity.FactionOwner;
StaticRefLib.EventLog.AddEvent(e);
//other info:
var keta = Angle.ToDegrees(ke.TrueAnomalyAtEpoch);
var obta = Angle.ToDegrees(OrbitProcessor.GetTrueAnomaly(orbit, atDateTime));
var tadif = Angle.ToDegrees(Angle.DifferenceBetweenRadians(keta, obta));
var pos1 = OrbitProcessor.GetPosition_AU(orbit, atDateTime);
var pos2 = OrbitProcessor.GetPosition_AU(orbit, ke.TrueAnomalyAtEpoch);
var d2 = Distance.AuToKm(pos1 - pos2).Length();
}
return(orbit);
}
public static OrbitDB FromVectorKM(Entity parent, double myMass, double parentMass, double sgp, Vector3 position, Vector3 velocity, DateTime atDateTime)
{
if (Distance.KmToAU(position.Length()) > OrbitProcessor.GetSOI(parent))
{
throw new Exception("Entity not in target SOI");
}
//var sgp = GameConstants.Science.GravitationalConstant * (myMass + parentMass) / 3.347928976e33;
var ke = OrbitMath.KeplerFromPositionAndVelocity(sgp, position, velocity, atDateTime);
OrbitDB orbit = new OrbitDB(parent, parentMass, myMass,
Distance.KmToAU(ke.SemiMajorAxis),
ke.Eccentricity,
Angle.ToDegrees(ke.Inclination),
Angle.ToDegrees(ke.LoAN),
Angle.ToDegrees(ke.AoP),
Angle.ToDegrees(ke.MeanAnomalyAtEpoch),
atDateTime);// - TimeSpan.FromSeconds(ke.Epoch));
var pos = OrbitProcessor.GetAbsolutePosition_AU(orbit, atDateTime);
return(orbit);
}
void SetOrbitHere(Entity entity, PropulsionAbilityDB propulsionDB, PositionDB positionDB, TranslateMoveDB moveDB, DateTime atDateTime)
{
propulsionDB.CurrentVectorMS = new Vector3(0, 0, 0);
double targetSOI = OrbitProcessor.GetSOI(moveDB.TargetEntity);
Entity targetEntity;
if (moveDB.TargetEntity.GetDataBlob <PositionDB>().GetDistanceTo(positionDB) > targetSOI)
{
targetEntity = moveDB.TargetEntity.GetDataBlob <OrbitDB>().Parent; //TODO: it's concevable we could be in another SOI not the parent (ie we could be in a target's moon's SOI)
}
else
{
targetEntity = moveDB.TargetEntity;
}
OrbitDB targetOrbit = targetEntity.GetDataBlob <OrbitDB>();
var orbitalVector = OrbitProcessor.GetOrbitalVector(targetOrbit, atDateTime);
var insertionVector2d = OrbitProcessor.GetOrbitalInsertionVector(moveDB.SavedNewtonionVector_AU, targetOrbit, atDateTime);
Vector3 parentOrbitalVector = new Vector3(orbitalVector.X, orbitalVector.Y, 0);
Vector3 insertionVector = new Vector3(insertionVector2d.X, insertionVector2d.Y, 0);
insertionVector += moveDB.ExpendDeltaV_AU; //TODO: only use it if we have it.
propulsionDB.RemainingDV_MS -= (float)Distance.AuToMt(moveDB.ExpendDeltaV_AU).Length();
OrbitDB newOrbit = OrbitDB.FromVector(targetEntity, entity, insertionVector, atDateTime);
if (newOrbit.Periapsis > targetSOI)
{
//TODO: find who's SOI we're currently in and create an orbit for that;
}
if (newOrbit.Apoapsis > targetSOI)
{
//TODO: change orbit to new parent at SOI change
}
positionDB.SetParent(targetEntity);
moveDB.IsAtTarget = true;
entity.RemoveDataBlob <TranslateMoveDB>();
entity.SetDataBlob(newOrbit);
newOrbit.SetParent(targetEntity);
}
/// <summary>
/// This was designed so that fast moving objects will get interpolated a lot more than slow moving objects
/// so fast moving objects shouldn't loose positional acuracy when close to a planet,
/// and slow moving objects won't have processor time wasted on them by calulcating too often.
/// However this seems to be unstable and looses energy, unsure why. currently set it to just itterate/interpolate every second.
/// so currently will be using more time to get through this than neccisary.
/// </summary>
/// <param name="entity">Entity.</param>
/// <param name="deltaSeconds">Delta seconds.</param>
public static void NewtonMove(Entity entity, int deltaSeconds)
{
NewtonMoveDB newtonMoveDB = entity.GetDataBlob <NewtonMoveDB>();
PositionDB positionDB = entity.GetDataBlob <PositionDB>();
double Mass_Kg = entity.GetDataBlob <MassVolumeDB>().Mass;
double ParentMass_kg = newtonMoveDB.ParentMass;
var manager = entity.Manager;
DateTime dateTimeFrom = newtonMoveDB.LastProcessDateTime;
DateTime dateTimeNow = manager.ManagerSubpulses.StarSysDateTime;
DateTime dateTimeFuture = dateTimeNow + TimeSpan.FromSeconds(deltaSeconds);
double deltaT = (dateTimeFuture - dateTimeFrom).TotalSeconds;
double secondsToItterate = deltaT;
while (secondsToItterate > 0)
{
double speed_kms = newtonMoveDB.CurrentVector_kms.Length();
//double timeStep = Math.Max(secondsToItterate / speed_kms, 1);
//timeStep = Math.Min(timeStep, secondsToItterate);
double timeStep = 1;//because the above seems unstable and looses energy.
double distanceToParent_m = Distance.AuToMt(positionDB.GetDistanceTo(newtonMoveDB.SOIParent.GetDataBlob <PositionDB>()));
distanceToParent_m = Math.Max(distanceToParent_m, 0.1); //don't let the distance be 0 (once collision is in this will likely never happen anyway)
double gravForce = GameConstants.Science.GravitationalConstant * (Mass_Kg * ParentMass_kg / Math.Pow(distanceToParent_m, 2));
Vector3 gravForceVector = gravForce * -Vector3.Normalise(positionDB.RelativePosition_AU);
double distance = Distance.AuToKm(positionDB.RelativePosition_AU).Length();
Vector3 totalForce = gravForceVector + newtonMoveDB.ThrustVector;
Vector3 acceleration_mps = totalForce / Mass_Kg;
Vector3 newVelocity = (acceleration_mps * timeStep * 0.001) + newtonMoveDB.CurrentVector_kms;
newtonMoveDB.CurrentVector_kms = newVelocity;
Vector3 deltaPos = (newtonMoveDB.CurrentVector_kms + newVelocity) / 2 * timeStep;
//Vector4 deltaPos = newtonMoveDB.CurrentVector_kms * timeStep;
positionDB.RelativePosition_AU += Distance.KmToAU(deltaPos);
double sOIRadius_AU = OrbitProcessor.GetSOI(newtonMoveDB.SOIParent);
if (positionDB.RelativePosition_AU.Length() >= sOIRadius_AU)
{
Entity newParent;
Vector3 parentRalitiveVector;
//if our parent is a regular kepler object (normaly this is the case)
if (newtonMoveDB.SOIParent.HasDataBlob <OrbitDB>())
{
var orbitDB = newtonMoveDB.SOIParent.GetDataBlob <OrbitDB>();
newParent = orbitDB.Parent;
var parentVelocity = OrbitProcessor.InstantaneousOrbitalVelocityVector(orbitDB, entity.Manager.ManagerSubpulses.StarSysDateTime);
parentRalitiveVector = Distance.KmToAU(newtonMoveDB.CurrentVector_kms) + parentVelocity;
var pvlen = Distance.AuToKm(parentVelocity.Length());
var vlen = newtonMoveDB.CurrentVector_kms.Length();
var rvlen = Distance.AuToKm(parentRalitiveVector.Length());
}
else //if (newtonMoveDB.SOIParent.HasDataBlob<NewtonMoveDB>())
{ //this will pretty much never happen.
newParent = newtonMoveDB.SOIParent.GetDataBlob <NewtonMoveDB>().SOIParent;
var parentVelocity = newtonMoveDB.SOIParent.GetDataBlob <NewtonMoveDB>().CurrentVector_kms;
parentRalitiveVector = Distance.KmToAU(newtonMoveDB.CurrentVector_kms + parentVelocity);
}
double newParentMass = newParent.GetDataBlob <MassVolumeDB>().Mass;
double sgp = GameConstants.Science.GravitationalConstant * (newParentMass + Mass_Kg) / 3.347928976e33;
Vector3 posRalitiveToNewParent = positionDB.AbsolutePosition_AU - newParent.GetDataBlob <PositionDB>().AbsolutePosition_AU;
var dateTime = dateTimeNow + TimeSpan.FromSeconds(deltaSeconds - secondsToItterate);
var kE = OrbitMath.KeplerFromPositionAndVelocity(sgp, posRalitiveToNewParent, parentRalitiveVector, dateTime);
if (kE.Eccentricity < 1) //if we're going to end up in a regular orbit around our new parent
{
/*
* var newOrbit = OrbitDB.FromKeplerElements(
* newParent,
* newParentMass,
* Mass_Kg,
* kE,
* dateTime);
*/
var newOrbit = OrbitDB.FromVector(newParent, entity, parentRalitiveVector, dateTime);
entity.RemoveDataBlob <NewtonMoveDB>();
entity.SetDataBlob(newOrbit);
positionDB.SetParent(newParent);
var currentPos = Distance.AuToKm(positionDB.RelativePosition_AU);
var newPos = OrbitProcessor.GetPosition_AU(newOrbit, dateTime);
var newPosKM = Distance.AuToKm(newPos);
positionDB.RelativePosition_AU = newPos;
break;
}
else //else we're in a hyperbolic trajectory around our new parent, so just coninue the newtonion move.
{
positionDB.SetParent(newParent);
newtonMoveDB.ParentMass = newParentMass;
newtonMoveDB.SOIParent = newParent;
}
}
secondsToItterate -= timeStep;
}
newtonMoveDB.LastProcessDateTime = dateTimeFuture;
}