private static IEnumerable <SusceptibleRigidbody2D> GetSusceptibleBodies(ForceKind kind)
{
// TODO: cache 'em, cache em all!
var bodies = GameObject.FindObjectsOfType <Rigidbody2D> ();
foreach (var body in bodies)
{
var material = ForceReceiver.GetMaterial(body.gameObject);
float influence = material.GetInfluence(kind);
if (influence == 0)
{
continue;
}
yield return(new SusceptibleRigidbody2D(body, influence, material));
}
}
void OnCollisionEnter(Collision collision)
{
if (collision.gameObject.layer != LayerMask.NameToLayer("Destructable"))
{
return;
}
ForceReceiver receiver = collision.gameObject.GetComponent <ForceReceiver>();
if (receiver != null)
{
receiver.OnHit(Velocity);
}
// print("Hit with force: " + Velocity + " magnitude: " + Velocity.magnitude);
// Debug.
// foreach (ContactPoint contact in collision.contacts)
// {
// Debug.DrawRay(contact.point, contact.normal, Color.white, 1f);
// }
}
private void ApplyToBodies(float timeFactor)
{
var ignoreSelfCollisionPredicate = Spatial.IgnoreSelfCollisionPredicate(rigidbody2D);
// TODO: consider using CircleCollider2D trigger. I don't know how much faster trigger will be.
var contactsByBody = Spatial.GetCircleContactsByBody(
Origin, Radius, 0, Radius,
hit => hit.collider.attachedRigidbody == null || ignoreSelfCollisionPredicate(hit),
NumSweepDirections,
LayerMask
);
#if UNITY_EDITOR
lastFrameContacts = contactsByBody;
#endif
foreach (var bodyAndContacts in contactsByBody)
{
var body = bodyAndContacts.Key;
var bodyContacts = bodyAndContacts.Value;
float influence = ForceReceiver.GetInfluence(body.gameObject, Kind);
if (influence == 0)
{
continue;
}
float forceAmount = PhysicsHelper.ConvertToNewtons(Amount, Mode, body.gameObject);
forceAmount *= influence * timeFactor * AnimatedMultiplier;
if (DecreaseWithDistance)
{
var contactForceFactors = new ContactForceFactor [bodyContacts.Count];
float maxDistanceFactor = float.NegativeInfinity;
float distanceFactorSum = 0;
for (int i = 0; i < bodyContacts.Count; i++)
{
var contact = bodyContacts [i];
float distanceFactor = 1 - contact.Distance / Radius;
if (distanceFactor > maxDistanceFactor)
{
maxDistanceFactor = distanceFactor;
}
distanceFactorSum += distanceFactor;
var cff = new ContactForceFactor(contact, distanceFactor);
contactForceFactors [i] = cff;
}
forceAmount *= maxDistanceFactor;
/* Sum of all contact factors multiplied
* by following factorScale will be 1. */
float factorScale = 1 / distanceFactorSum;
foreach (var cff in contactForceFactors)
{
var contact = cff.Contact;
float distanceFactor = cff.Factor * factorScale;
float contactForceAmount = forceAmount * distanceFactor;
var forceVector = contact.Direction * contactForceAmount;
if (SendForceMessage(body.gameObject, forceVector, contact.Point))
{
body.AddForceAtPosition(forceVector, contact.Point);
}
}
}
else
{
forceAmount /= bodyContacts.Count;
foreach (var contact in bodyContacts)
{
var forceVector = contact.Direction * forceAmount;
if (SendForceMessage(body.gameObject, forceVector, contact.Point))
{
body.AddForceAtPosition(forceVector, contact.Point);
}
}
}
}
}
