public CollisionDetector()
{
_collisions = new List<Collision>();
_collisionsWrapper = new ReadOnlyCollection<Collision>(_collisions);
_geometry = new List<Geometry>();
_tester = new SatTester();
}
public void FindContacts(SatTester tester, int maxContacts)
{
if (!IsActive)
return;
// perform SAT collision detection
SatResult? r = tester.FindIntersection(A, B);
if (r == null)
{
Contacts.Clear();
return;
}
SatResult result = r.Value;
_normal = result.NormalAxis;
PenetrationDepth = result.Penetration;
// find all vertices in a which are inside b, add them as contacts
var aVertices = A.GetVertices(result.NormalAxis);
for (int i = 0; i < aVertices.Length; i++)
{
if (_newContacts.Count == maxContacts)
break;
if (B.Contains(aVertices[i]))
_newContacts.Add(new Contact(aVertices[i], A, i));
}
// find all vertices in b which are inside a, add them as contacts
var bVertices = B.GetVertices(-result.NormalAxis);
for (int i = 0; i < bVertices.Length; i++)
{
if (Contacts.Count == maxContacts)
break;
if (A.Contains(bVertices[i]))
_newContacts.Add(new Contact(bVertices[i], B, i));
}
// add the deepest point if we found no others
if (_newContacts.Count == 0)
_newContacts.Add(new Contact(result.DeepestPoint, A, 0));
// merge new contacts with the old ones
MergeContacts();
if (!_initialised)
{
A.collidingWith.Add(B);
B.collidingWith.Add(A);
_initialised = true;
}
}