The Fusion planar tracker is a simple and capable tracking tool in DaVinci Resolve. It allows you to track even surfaces and you can corner-pin effects on top of them.
After adding the Planar Tracker node, you first select the area of interest with a Polygon. This area needs to be in the same flat plane where you want to work on for your final effect. But, the two areas do not need to be identical. Good trackable contrast often lies outside of the area of your final composite.
The planar tracker has two Tracker types: “Point” and “Hybrid Point/Area”. Typically, “Hybrid Point/Area” is more accurate, but not always. This option can still work well if there are only a few high contrast points available to track.
The downside is that this method always considers the whole area and cannot discard false information. Strong highlights, objects that pass through, or reflections can literally throw the tracker off track. In case of such conflicting data, the “Point” tracker may run more stable.
If your tracked area is getting occluded, you have two options. You can attach an occlusion mask or you can change your tracked area for parts of the sequence.
Finally, you can intervene and fix areas that you were unable to track. If you use the Corner Pin, this can be as simple as animating the corner points for those few frames.