Occlusion also present significant challenges in positional tracking. The problem is especially prominent in optical-based tracking systems when objects are hidden from the tracking camera because they are behind other objects.
AR and VR
One of two main problems standing in the way of a seamless integration of virtual objects into a real scene is the lack of information using traditional methods for 3D reconstruction. This lack of detail makes an accurate estimation of boundaries very difficult. The second problem is camera movement between two frames. VR or AR applications that are not completely aware of all differences cannot adequately compensate for this movement, which can result in jittering of virtual objects.
Several different methods and techniques for dealing with interactive occlusion between real and virtual objects were already proposed. These include simulating the occlusion of virtual objects by a representation of the user modeled as kinematic chains of articulated solids, or, for example, by computation and taking into account of the uncertainty on the viewpoints.
In positional tracking, objects can become hidden from the tracking camera when they are behind other objects.