/// <summary>
/// Assigning the target group and the fringe group
/// </summary>
private void UpdateActiveGroups(List <Boid> boidList)
{
targetGroup.Clear();
fringeGroup.Clear();
if (boidList == null || boidList.Count == 0)
{
return;
}
//find the nearest boid and form the target group from it and its neighbours
Boid nearestBoid = BoidUtility.GetNearest(boidList, Position);
targetGroup.Add(nearestBoid);
foreach (var boid in nearestBoid.Neighbours)
{
targetGroup.Add(boid);
}
//form the fringe group from the neighbours of the target group that arent in the target group
foreach (var boid in targetGroup)
{
foreach (var neighbour in boid.Neighbours)
{
if (!targetGroup.Contains(neighbour) && !fringeGroup.Contains(neighbour))
{
fringeGroup.Add(neighbour);
}
}
}
}
/// <summary>
/// Vector towards the nearest target.
/// This is the actual attack of a particular boid. As we get closer to a boid,
/// our tendency to attack it increases.
/// </summary>
private Vector3 CalculateAttackEagerness(HashSet <Boid> targets, float currentWithdrawalWeight)
{
if (targets == null || targets.Count == 0)
{
return(Vector3.zero);
}
var toNearestBoid = BoidUtility.GetNearest(targets, Position).Position - Position;
var weight = 1f - Mathf.Clamp01(toNearestBoid.sqrMagnitude / attackRadiusSqr); //weight nearer boids most heavily
return(toNearestBoid.normalized * weight * (1f - currentWithdrawalWeight));
}
/// <summary>
/// Vector away from other predators.
/// This prevents the predator from targeting boids that are also
/// being targeted by other predators.
/// </summary>
private Vector3 CalculateIndependence(List <BoidPredator> predators)
{
HashSet <BoidPredator> others = new HashSet <BoidPredator>(predators);
others.Remove(this);
if (others.Count > 0)
{
var toNearestPred = BoidUtility.GetNearest(others, Position).Position - Position;
var weight = 1f - Mathf.Clamp01(toNearestPred.sqrMagnitude / viewRadius); //weight nearer predators most heavily
return(-toNearestPred.normalized * weight);
}
return(Vector3.zero);
}
private bool CheckForTargetCapture()
{
if (targetGroup == null || targetGroup.Count == 0)
{
return(false);
}
var nearestBoid = BoidUtility.GetNearest(targetGroup, Position);
if ((nearestBoid.Position - Position).sqrMagnitude <= captureRadiusSqr)
{
nearestBoid.Kill();
killCount++;
return(true);
}
return(false);
}