I can merge two rectangular video like first picture, using AVMutableComposition.
I want to merge two triangle shape video to make rectangular video like second one, also I can crop the video in to rectangle shape, but now am stuck on make the video in to triangle shape feel. When I try to add triangle overlay, It hide the second video, So I want to know, we can add overlay on a video without affect the second video while merge two video, like the second image.
