Separation ray shape for 2D collisions. Separation ray shape for 2D collisions. A ray is not really a collision body; instead, it tries to separate itself from whatever is touching its far endpoint. It's often useful for characters. The ray's length. If [code]false[/code] (default), the shape always separates and returns a normal along its own direction. If [code]true[/code], the shape can return the correct normal and separate in any direction, allowing sliding motion on slopes.