This video recreates a scenario where you are trying to track a surface but due to object movement and camera movement, the objects go off-screen, come back on and go off-screen again. So maintaining a decent track is a tricky challenge. This video will show you how to create isolated areas with Action Gmasks to build a reference pattern which will help the planar tracker perform the track. As with all tracking, there is no perfect method but this will certainly get you 95% of the way there followed by some manual tweaking. You also have the added benefit of having your tracking data in an Axis node that allows you to direct the tracking information within the Action composite.