public override void Initialize(Collidable newCollidableA, Collidable newCollidableB)
{
sphereA = (ConvexCollidable<SphereShape>)newCollidableA;
sphereB = (ConvexCollidable<SphereShape>)newCollidableB;
if (sphereA == null || sphereB == null)
{
throw new Exception("Inappropriate types used to initialize pair.");
}
}