Scaling slider for LinearTransform

Dear community,
I am trying to register multiple 2D in-situ images to a 3D CT brain scan. For this purpose I do an initial coarse alignment by a manual linear transform. In a second step I apply landmark registration. I finally use the registered data to segment specific brain areas in the CT scan based on the overlayed in-situ data.

For the first manual alignment it would be very helpful to have an additional “Scaling” slider in the transform module. I currently manually alter the transform matrix for this purpose or use the image spacing parameters from the “volume” module.

I don’t see any technical reason why there should not be a scaling slider in the transformation module.
What am I missing? Thank you in advance!

There’s no technical reason except that typically only rigid registration is used for most volumetric registration (since they are already in calibrated units). But I suppose it wouldn’t hurt to have an advanced checkbox or something that exposes a scale slider. Could also add shears if people would find it useful.

Thank you for the fast reply. This would be very helpful indeed!

I’m not sure if anyone has the time to add this, but you can file a feature request on the issue tracker and anyone can vote for the feature using the :+1: emoji. This is an example of a good intermediate programming task that would be an excellent learning project for a new developer who wants to learn the C++ side of Slicer (adding this involves making changes to the Transforms loadable module).

If you just want a more easy way to scale a transform to accelerate your work of course you can add a little script to implement the feature.