public SteeringBehavior(FlyingEntity agent)
{
_flyingEntity = agent;
TargetAgent1 = null;
TargetAgent2 = null;
decelerationRate = DecelerationRate.NORMAL;
SummingMethod = SumMethod.WEIGHTED_AVG;
_path = new Path
{
Looped = true
};
}
/// <summary>
/// This behaviour will give return a steering force that will which will direct the agent to the TargetPosition.
/// Unlike seek, this behaviour will decelerate when the the agent is close to the targetPosition.
/// </summary>
/// <param name="TargetPos"></param>
/// <param name="deceleration"></param>
/// <returns>Steering Force</returns>
public Vector2D Arrive(Vector2D TargetPos,
DecelerationRate deceleration)
{
if (_flyingEntity.Pos.x == TargetPos.x && _flyingEntity.Pos.y == TargetPos.y)
{
return(Vector2D.Zero);
}
ClampPositions(ref _flyingEntity, TargetPos);
Vector2D ToTarget = TargetPos - _flyingEntity.Pos;
// Calculate the distance to the target.
double dist = ToTarget.Length();
if (dist > 0)
{
/* Because Deceleration is enumerated as an int, this value is required
* to provide fine tweaking of the deceleration. */
const double DecelerationTweaker = 2.0;
/* Calculate the speed required to reach the target given the desired
* deceleration. */
double speed = dist / ((double)deceleration * DecelerationTweaker);
// Make sure the velocity does not exceed the max.
speed = Math.Min(speed, _flyingEntity.MaxSpeed);
/* From here proceed just like Seek except we don't need to normalize
* the ToTarget vector because we have already gone to the trouble
* of calculating its length: dist. */
Vector2D DesiredVelocity = ToTarget * speed / dist;
return(DesiredVelocity - _flyingEntity.Velocity);
}
return(new Vector2D(0, 0));
}
