I would like to add a HU threshold value parameter for DRR calculation, e.g. input cli option --hu-threshold <value>. Values below threshold would have air HU value -1000. That feature could be useful for better visualization of bone structure. Default value will be -1000. I will also add that feature in SlicerRT module that computes DRR image.
What do you think about that? Could it be useful for plastimatch?