A user, a manipulator such as a hand, and at least one entity such as a virtual or augmented reality object are in an interface such as a 3D environmental interface. The manipulation distance is the distance between a reference feature of the user and a manipulation feature of the manipulator. The entity distance is the distance between the reference feature and an entity feature of the entity. When the manipulation distance becomes greater than the entity distance, the entity is caused to fade, disappear, move out of the way, shrink, etc. so as to be less of an obstruction to the user's field of view, for example to avoid obstructing more distant entities. Other factors than the manipulation distance and entity distance may be considered in determining whether to reduce the obstructivity of the entity, and exceptions to the obstruction relation may be considered.