//ARRIVE
public static Vector2 Arrive(Vector2 CurrentPosition, Vector2 TargetPosition, float MaxSpeed, Vector2 CurrentDirection, float Threshhold)
{
//Get ToTarget vector
Vector2 ToTarget = TargetPosition - CurrentPosition;
//Get Distance to Target
float ToTargetMagnitude = VectorArithmetic.VectorLength(ToTarget);
//If Distance is Less than Threshold...
Vector2 DesiredVelocity = VectorArithmetic.VectorNormalized(ToTarget) * MaxSpeed * (ToTargetMagnitude / Threshhold);
//Get Current Velocity
Vector2 CurrentVelocity = CurrentDirection;
//Return Steering Force
return(DesiredVelocity - CurrentVelocity);
}
//SEEK OR FREE
public static Vector2 SeekOrFlee(Vector2 CurrentPosition, Vector2 TargetPosition, float MaxSpeed, Vector2 CurrentDirection, bool TrueIfSeekFalseIfFlee)
{
//Get Desired Velocity
Vector2 DesiredVelocity;
//Seek Or Flee Algorithm
if (TrueIfSeekFalseIfFlee == true)
{
DesiredVelocity = VectorArithmetic.VectorNormalized(TargetPosition - CurrentPosition) * MaxSpeed;
}
else
{
DesiredVelocity = VectorArithmetic.VectorNormalized(CurrentPosition - TargetPosition) * MaxSpeed;
}
//Get Current Velocity
Vector2 CurrentVelocity = CurrentDirection;
//Return Steering Force
return(DesiredVelocity - CurrentVelocity);
}
//PURSUIT OR EVADE
public static Vector2 PursuitOrEvade(Vector2 SelfCurrentPosition, Vector2 EnemyCurrentPosition, Vector2 SelfCurrentDirection,
Vector2 EnemyCurrentDirection, float SelfMaxSpeed, float EnemyMaxSpeed, bool TrueIfPursuitFalseIfEvade)
{
//Default Values
Vector2 ReturnThis;
float RelativeHeading = 0;
Vector2 ToEnemy = EnemyCurrentPosition - SelfCurrentPosition;
//Find Relative Heading for Pursuit
if (TrueIfPursuitFalseIfEvade == true)
{
RelativeHeading = VectorArithmetic.DotProduct(VectorArithmetic.VectorNormalized(SelfCurrentDirection), VectorArithmetic.VectorNormalized(EnemyCurrentDirection));
}
//If Both Self and Enemy facing the same Direction?
if (RelativeHeading > 0 && TrueIfPursuitFalseIfEvade == true)
{
ReturnThis = SeekOrFlee(SelfCurrentPosition, EnemyCurrentPosition, SelfMaxSpeed, SelfCurrentDirection, true);
}
else
{
//Where the Enemy will be...
float LookAheadTime = VectorArithmetic.VectorLength(ToEnemy) / (SelfMaxSpeed + EnemyMaxSpeed);
Vector2 EnemyFuturePosition = EnemyCurrentPosition + EnemyCurrentDirection * LookAheadTime;
//Pursuit or Evade Future Position
if (TrueIfPursuitFalseIfEvade == true)
{
ReturnThis = SeekOrFlee(SelfCurrentPosition, EnemyFuturePosition, SelfMaxSpeed, SelfCurrentDirection, true);
}
else
{
ReturnThis = SeekOrFlee(SelfCurrentPosition, EnemyFuturePosition, SelfMaxSpeed, SelfCurrentDirection, false);
}
}
return(ReturnThis);
}
