public void RemoveCollision(Collision c)
{
if (!Enumerable.Contains(_collideables, c)) return;
_collideables.Remove(c);
_pairs.RemoveWhere(pair => pair.A.Equals(c) || pair.B.Equals(c));
}
public void AddCollision(Collision c)
{
//Check if the Collision is already in the list.
if (Enumerable.Contains(_collideables, c)) return;
_collideables.Add(c);
//Generate our pairs
ReconfigurePairs(c);
}
/// <summary>
/// Reconfigures the pairs for a Collision c
/// </summary>
/// <param name="c">A collision.</param>
public void ReconfigurePairs(Collision c)
{
//Remove pairs with this collision in it
foreach (var pair in _pairs.ToArray().Where(pair => pair.A.Equals(c) || pair.B.Equals(c)))
{
_pairs.Remove(pair);
}
//Recalculate pairs with this new collision
foreach (var other in _collideables)
{
if (c.Equals(other)) continue;
if (CanObjectsPair(c, other))
{
var p = new Pair(c, other);
_pairs.Add(p);
}
}
}
//Collision resolver methods
/// <summary>
/// Uses a table to test collision between various shapes
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static Manifold CheckCollision(Collision a, Collision b)
{
Shape aShape, bShape;
aShape = a.GetDependency<Shape>(Collision.DEPENDENCY_SHAPE);
bShape = b.GetDependency<Shape>(Collision.DEPENDENCY_SHAPE);
Manifold manifold = new Manifold(a,b);
if (aShape is AABB && bShape is AABB)
AABBvsAABB((AABB)aShape, (AABB)bShape, ref manifold);
else if (aShape is Circle && bShape is Circle)
CircleVSCircle((Circle)aShape, (Circle)bShape, ref manifold);
else
throw new Exception("No existing methods for this kind of collision!");
return manifold;
}
public static bool CanObjectsResolve(Collision resolver, Collision other)
{
return resolver.ResolutionGroupMask.HasMatchingBit(other.ResolutionGroupMask) //Compare the pair mask one sided.
&& resolver.Enabled && other.Enabled && !resolver.Immovable;
}
//Static methods
/// <summary>
/// Compares the masks and checks to see if they should be allowed to form a pair.
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns>Whether or not the the two objects should be paired</returns>
public static bool CanObjectsPair(Collision a, Collision b)
{
return (a.GroupMask.HasMatchingBit(b.PairMask) || //Compare the pair masks to the group masks.
a.PairMask.HasMatchingBit(b.GroupMask)) && a.Enabled && b.Enabled;
}
public Manifold(Collision a, Collision b)
: this()
{
_pair = new Pair(a, b);
}
public void OnCollision(Collision c)
{
_collidedWith.Add(c);
if (CollideEvent != null)
CollideEvent(c);
}