protected override Vector3 CalculateForce()
{
if (_menace == null || (Vehicle.Position - _menace.Position).sqrMagnitude > _sqrSafetyDistance)
{
return(Vector3.zero);
}
// offset from this to menace, that distance, unit vector toward menace
var position = Vehicle.PredictFutureDesiredPosition(_predictionTime);
var offset = _menace.Position - position;
var distance = offset.magnitude;
var roughTime = distance / _menace.Speed;
var predictionTime = ((roughTime > _predictionTime) ?
_predictionTime :
roughTime);
//var target = _menace.PredictFuturePosition(predictionTime);
var target = _menace.PredictFuturePosition(predictionTime) + _offset;
// This was the totality of SteerToFlee
var desiredVelocity = position - target;
//Debug.DrawRay(Vehicle.Position, desiredVelocity, Color.blue);
return(desiredVelocity - Vehicle.DesiredVelocity);
}
/// <summary>
/// Calculates the force necessary to stay on the navmesh
/// </summary>
/// <returns>
/// Force necessary to stay on the navmesh, or Vector3.zero
/// </returns>
/// <remarks>
/// If the Vehicle is too far off the navmesh, Vector3.zero is retured.
/// This won't lead back to the navmesh, but there's no way to determine
/// a way back onto it.
/// </remarks>
protected override Vector3 CalculateForce()
{
NavMeshHit hit;
/*
* While we could just calculate line as (Velocity * predictionTime)
* and save ourselves the substraction, this allows other vehicles to
* override PredictFuturePosition for their own ends.
*/
var futurePosition = Vehicle.PredictFuturePosition(_minTimeToCollision);
var movement = futurePosition - Vehicle.Position;
#if ANNOTATE_NAVMESH
Debug.DrawRay(Vehicle.Position, movement, Color.cyan);
#endif
if (_offMeshCheckingEnabled)
{
var probePosition = Vehicle.Position + _probePositionOffset;
Profiler.BeginSample("Off-mesh checking");
NavMesh.SamplePosition(probePosition, out hit, _probeRadius, _navMeshLayerMask);
Profiler.EndSample();
if (!hit.hit)
{
// we're not on the navmesh
Profiler.BeginSample("Find closest edge");
NavMesh.FindClosestEdge(probePosition, out hit, _navMeshLayerMask);
Profiler.EndSample();
if (hit.hit)
{
// closest edge found
#if ANNOTATE_NAVMESH
Debug.DrawLine(probePosition, hit.position, Color.red);
#endif
return((hit.position - probePosition).normalized * Vehicle.MaxForce);
} // no closest edge - too far off the mesh
#if ANNOTATE_NAVMESH
Debug.DrawLine(probePosition, probePosition + Vector3.up * 3, Color.red);
#endif
return(Vector3.zero);
}
}
Profiler.BeginSample("NavMesh raycast");
NavMesh.Raycast(Vehicle.Position, futurePosition, out hit, _navMeshLayerMask);
Profiler.EndSample();
if (!hit.hit)
{
return(Vector3.zero);
}
Profiler.BeginSample("Calculate NavMesh avoidance");
var moveDirection = Vehicle.Velocity.normalized;
var avoidance = OpenSteerUtility.PerpendicularComponent(hit.normal, moveDirection);
avoidance.Normalize();
#if ANNOTATE_NAVMESH
Debug.DrawLine(Vehicle.Position, Vehicle.Position + avoidance, Color.white);
#endif
avoidance += moveDirection * Vehicle.MaxForce * _avoidanceForceFactor;
#if ANNOTATE_NAVMESH
Debug.DrawLine(Vehicle.Position, Vehicle.Position + avoidance, Color.yellow);
#endif
Profiler.EndSample();
return(avoidance);
}
