I am rotoscoping an an animation frame by frame. Each picture lasts 2 frames. The bezier mask wants to interpolate and move between the keyframes. I would like it to hold for two frames and then snap into place for the next picture. Motion continues to want to split the difference between the shapes with interpolation. I have tried copying keyframes. I have tried changing interpolation to linear. This seems like it should be so easy, but I'm frustrated right now.