private void processCollisions() {
		//Quad Tree implementation
		//*
		QuadTree qt = new QuadTree(0, new Rectangle(0, 0, 1280, 720));
		for(Entity e : entities) {
			if(e.hitbox != null) {
				qt.insert(e);
			}
		}
		
		for(Entity e : entities) {
			if(e instanceof Collidable && e.hitbox != null) {
				List<Entity> list = new ArrayList<Entity>();
				qt.retrieve(list, e);
				for(Entity other : list) {
					if(e != other && other.hitbox.intersects(e.hitbox)) {
						((Collidable)e).doCollisionWith(other);
					}
				}
			}
		}
	}