public static BoidObject[] GetNeighbours(BoidObject Boid) // get array of neighbouring boids within vision distance
{
int viewLeft = Boid.IntPosX - (VisionDistance / 2);
int viewRight = Boid.IntPosX + (VisionDistance / 2);
int viewUp = Boid.IntPosY + (VisionDistance / 2);
int viewDown = Boid.IntPosY - (VisionDistance / 2);
BoidObject[] Neighbours = new BoidObject[] {};
int neighbourCount = 0;
for (int i = 0; i < BoidArray.Length; i++)
{
if (viewLeft <BoidArray[i].IntPosX& viewRight> BoidArray[i].IntPosX)
{
if (viewDown <BoidArray[i].IntPosY& viewUp> BoidArray[i].IntPosY)
{
Array.Resize(ref Neighbours, Neighbours.Length + 1);
Neighbours[neighbourCount] = BoidArray[i];
neighbourCount = neighbourCount + 1;
}
}
}
return(Neighbours);
}
public static float GetDistance(BoidObject Boid1, BoidObject Boid2)
{
double DiffX = Boid1.PosX - Boid2.PosX;
double DiffY = Boid1.PosY - Boid2.PosY;
float PosDiff = (float)Math.Sqrt(DiffX * DiffX + DiffY * DiffY);
return(PosDiff);
}
public static void GenerateBoids(int x, int y)
{
BoidObject Boid = new BoidObject();
Array.Resize(ref BoidArray, BoidArray.Length + 1);
Boid.PosX = x;
Boid.PosY = y;
BoidArray[BoidArray.Length - 1] = Boid;
}
// public static ParallelOptions LimitCores = new ParallelOptions();
public static void Reset(int StartX, int StartY)
{
int BoidCount = 0; // initial number of boids
BoidArray = new BoidObject[BoidCount];
for (int i = 0; i < BoidCount; i++)
{
BoidObject Boid = new BoidObject();
Boid.PosX = StartX;
Boid.PosY = StartY;
BoidArray[i] = Boid;
}
}
public static double[] CohesionCalc(BoidObject Boid, BoidObject[] Neighbours) // Aim to center of surrounding boids
{
double SumOfPosX = 0;
double SumOfPosY = 0;
for (int i = 0; i < Neighbours.Length; i++)
{
SumOfPosX = SumOfPosX + Neighbours[i].PosX;
SumOfPosY = SumOfPosY + Neighbours[i].PosY;
}
double AveragePosX = SumOfPosX / Neighbours.Length;
double AveragePosY = SumOfPosY / Neighbours.Length;
double[] PosDiff = new double[2];
PosDiff[0] = (AveragePosX - Boid.PosX) * CohesionWeight;
PosDiff[1] = (AveragePosY - Boid.PosY) * CohesionWeight;
return(PosDiff);
}
public static double[] AlignmentCalc(BoidObject Boid, BoidObject[] Neighbours) // Aim to match the velocity of surrounding boids
{
double SumOfVelX = 0;
double SumOfVelY = 0;
for (int i = 0; i < Neighbours.Length; i++)
{
SumOfVelX = SumOfVelX + Neighbours[i].VelX;
SumOfVelY = SumOfVelY + Neighbours[i].VelY;
}
double AvgVelX = SumOfVelX / Neighbours.Length;
double AvgVelY = SumOfVelY / Neighbours.Length;
double[] VelocityDiff = new double[2];
VelocityDiff[0] = (AvgVelX - Boid.VelX) * AlignmentWeight;
VelocityDiff[1] = (AvgVelY - Boid.VelY) * AlignmentWeight;
return(VelocityDiff);
}
public static double[] SeparateCalc(BoidObject Boid, BoidObject[] Neighbours) // find vector in opposite direction of neighbouring boids
{
double SumCloseX = 0;
double SumCloseY = 0;
for (int i = 0; i < Neighbours.Length; i++)
{
float PosDiff = GetDistance(Boid, Neighbours[i]);
if (PosDiff < 10)
{
SumCloseX = SumCloseX + (Boid.PosX - Neighbours[i].PosX);
SumCloseY = SumCloseY + (Boid.PosY - Neighbours[i].PosY);
}
}
double[] Separate = new double[2];
Separate[0] = SumCloseX * SeparateWeight;
Separate[1] = SumCloseY * SeparateWeight;
return(Separate);
}