face replacement, Nuke

- roto face you want to replace.
- cameraTrack the face. (keep the errors less than 1px in the output window.), solve camera and create scene.
- readGeo and add 3d face model to the scene
- project the footage onto the face obj from the camera just created.
- place the obj where it matches the projected image.
- connect the scene to a  scanlineRenderer and  the projection mode to uv.
- Now u have animating texture on the face obj.
- track original face wih trackers  apply the positions to SplineWarp points. or use GridWarp.