1. A computing system, comprising: a logic subsystem; a data holding subsystem holding instructions executable by the logic subsystem to: translate a world space position of a hand of a human target to a screen space position of a user interface; lock the hand to a visible handle of the user interface if world space parameters of the hand overcome a grab threshold of the visible handle; when the hand is locked to the visible handle, translate a world space position of the hand to a screen space visible handle position that is constrained along one or more interface guides; unlock the hand from the visible handle at a release position of the visible handle if world space parameters of the hand overcome a release threshold of the visible handle; and retain the visible handle at the release position after the hand is unlocked from the visible handle.