Limitation or user error?

I am trying to track the door of a car moving across the screen. Moving FASTER than that car and as a result, briefly obscuring it from the viewer, is another car moving across the screen “closer” to the viewer.
The spline on the door of my tracked car gets pushed off by the other car. Am I doing something wrong?
Thank you - any help would be great!

>From what I understand you’re describing, it sounds like you need to draw a spline around the obscuring car and put that in the layer above the door track. Mocha looks at things in the top of the layer pile as closest to the camera and the bottom of the layer pile as farthest from the camera, which means it holds those upper layers out of the layers below them.
If you have obscuring objects throwing your track off, it’s best to garbage roto them out in a layer above as a kind of “holdout matte.”
Let me know if you have any more questions.