I’ve implemented this, it’s available in latest Slicer Preview Release (I’ve pushed some more fixes today, so if inverse transform computation is not robust then wait for tomorrow’s release). The Curve Planar Reformat module provides a “straightening” transform, which transforms points from original image space to the straightened image. You can then add/delete/modify points in the straightened image space. To get these point positions in the original image space again, remove the straightening transform. See demo video here:
