function Collision( node, instance, position, distance, normal, hit )
{
	this.position = vec3.create();
	if(position)
		this.position.set(position);
	this.node = node || null; //the node belonging to this colliding object
	this.instance = instance || null; //could be a RenderInstance or a PhysicsInstance
	this.distance = distance || 0; //distance from the ray start
	this.normal = normal;
	this.hit = hit; //contains info about the collision in local space
}
Contains information about the collision of a ray and the scene
- position: vec3
- node: SceneNode
- instance: could be a RenderInstance or a PhysicsInstance
- distance: number
@class Collision
@namespace LS
@constructor
@param {SceneNode} node
@param {PhysicsInstance|RenderInstance} instance
@param {vec3} position collision position
@param {number} distance