/// <summary>
/// The squared distance does not require the square root. Hence, it is
/// computationally more efficient than the distance.
/// </summary>
/// <param name="self"></param>
/// <param name="other"></param>
/// <returns></returns>
public static double GetSquaredDistanceToPrimaryParticle(this PrimaryParticle self, PrimaryParticle other)
{
var x = Math.Pow(self.Position.X - other.Position.X, 2);
var y = Math.Pow(self.Position.Y - other.Position.Y, 2);
var z = Math.Pow(self.Position.Z - other.Position.Z, 2);
return(Math.Round(x + y + z, 6));
}
public static double GetDistanceToPosition(this PrimaryParticle self, Vector3 other)
{
var x = Math.Pow(self.Position.X - other.X, 2);
var y = Math.Pow(self.Position.Y - other.Y, 2);
var z = Math.Pow(self.Position.Z - other.Z, 2);
var distance = Math.Round(Math.Sqrt(x + y + z), 6);
return(distance);
}
public INeighborslist BuildEmpty3DNeighborsList()
{
// The neighborslist requires a particle to be build. Therefore, a dummy particle
// which can never be reached is added to the neighborslist
// this particle will never show up in an aggregate
var dummyPP = new PrimaryParticle(-1, new Vector3(-999999, -999999, -999999), 0);
return(new Accord3DNeighborslist(new List <PrimaryParticle> {
dummyPP
}));
}
private void CheckPeriodicBoundary(PrimaryParticle virtualParticle, double oneDPosition, double maxRadius, BoxDimension dim)
{
if (oneDPosition + virtualParticle.Radius >= dim.Upper - maxRadius)
{
virtualParticle.Position.X -= dim.Width;
AddParticlesToNeighborsList(virtualParticle);
}
else if (oneDPosition - virtualParticle.Radius <= dim.Lower + maxRadius)
{
virtualParticle.Position.X += dim.Width;
AddParticlesToNeighborsList(virtualParticle);
}
}
/// <summary>
/// A virtual particle is only within the neighborslist to ensure that any
/// particle that would hit another particle through periodic boundary conditions
/// can see this virtual particle
/// </summary>
/// <param name="primaryParticle"></param>
/// <returns></returns>
private PrimaryParticle GetVirtualParticle(PrimaryParticle primaryParticle)
{
return(new PrimaryParticle
{
Id = -1 * primaryParticle.Id,
Position = new Vector3
(
primaryParticle.Position.X,
primaryParticle.Position.Y,
primaryParticle.Position.Z
),
Radius = primaryParticle.Radius
});
}
public virtual void AddParticlesToNeighborsList(PrimaryParticle primaryParticle)
{
_kdTree.Add(primaryParticle.Position.ToArray(), primaryParticle);
}
public override void AddParticlesToNeighborsList(PrimaryParticle primaryParticle)
{
_kdTree.Add(primaryParticle.Position.ToXYArray(), primaryParticle);
}
public static double GetDistanceToVerticalAxis(this PrimaryParticle primaryParticle, PrimaryParticle neighbor)
{
return(Math.Sqrt(Math.Pow(primaryParticle.Position.X - neighbor.Position.X, 2) +
Math.Pow(primaryParticle.Position.Y - neighbor.Position.Y, 2)
));
}
public static double GetDistanceToVerticalAxis(this PrimaryParticle primaryParticle, double[] neighborPosition)
{
return(Math.Sqrt(Math.Pow(primaryParticle.Position.X - neighborPosition[0], 2) +
Math.Pow(primaryParticle.Position.Y - neighborPosition[1], 2)
));
}