/// <summary>
/// Checks if the specified geom intersect the specified point.
/// </summary>
/// <param name="geom">The geom.</param>
/// <param name="point">The point.</param>
/// <returns></returns>
public bool Intersect(Geom geom, ref Vector2 point)
{
//Lookup the geometry's distancegrid
DistanceGridData gridData = _distanceGrids[geom.id];
Feature feature;
return(gridData.Intersect(ref point, out feature));
}
/// <summary>
/// Finds the contactpoints between the two geometries.
/// </summary>
/// <param name="geomA">The first geom.</param>
/// <param name="geomB">The second geom.</param>
/// <param name="contactList">The contact list.</param>
public void Collide(Geom geomA, Geom geomB, ContactList contactList)
{
int vertexIndex = -1;
//Lookup distancegrid A data from list
DistanceGridData geomAGridData = _distanceGrids[geomA.id];
//Iterate the second geometry vertices
for (int i = 0; i < geomB.worldVertices.Count; i++)
{
if (contactList.Count == PhysicsSimulator.MaxContactsToDetect)
{
break;
}
vertexIndex += 1;
_vertRef = geomB.WorldVertices[i];
geomA.TransformToLocalCoordinates(ref _vertRef, out _localVertex);
//The geometry intersects when distance <= 0
//Continue in the list if the current vector does not intersect
if (!geomAGridData.Intersect(ref _localVertex, out _feature))
{
continue;
}
//If the geometries collide, create a new contact and add it to the contact list.
if (_feature.Distance < 0f)
{
geomA.TransformNormalToWorld(ref _feature.Normal, out _feature.Normal);
Contact contact = new Contact(geomB.WorldVertices[i], _feature.Normal, _feature.Distance, new ContactId(geomB.id, vertexIndex, geomA.id));
contactList.Add(contact);
}
}
//Lookup distancegrid B data from list
DistanceGridData geomBGridData = _distanceGrids[geomB.id];
//Iterate the first geometry vertices
for (int i = 0; i < geomA.WorldVertices.Count; i++)
{
if (contactList.Count == PhysicsSimulator.MaxContactsToDetect)
{
break;
}
vertexIndex += 1;
_vertRef = geomA.WorldVertices[i];
geomB.TransformToLocalCoordinates(ref _vertRef, out _localVertex);
if (!geomBGridData.Intersect(ref _localVertex, out _feature))
{
continue;
}
if (_feature.Distance < 0f)
{
geomB.TransformNormalToWorld(ref _feature.Normal, out _feature.Normal);
_feature.Normal = -_feature.Normal;
Contact contact = new Contact(geomA.WorldVertices[i], _feature.Normal, _feature.Distance, new ContactId(geomA.id, vertexIndex, geomB.id));
contactList.Add(contact);
}
}
}
