Can't really recall that feature from the S4. What I do know, however, is that the 'Light Effect' from the lockscreen did not refer to the light sensor in any way. It was the animation effect that would show up on your screen if you hovered your finger over it and when you eventually unlocked your screen. If the feature you're referring to existed, it would have been under Gestures settings (probably Air Gestures?) but not on the lockscreen ones.