negative scale causes problem with volume rendering

Hi, I need to align several datasets, by rotating and scaling one of them to match the others.

When I apply a -1 scale in the y direction to a Resample to Image data, the volume data is not entirely rendered anymore but only some surfaces remain. See attachments for the before/after scaling.

Any guess on what’s happening or what I’m doing wrong?




Hi Matthieu,

Looks like your attachements are missing.

afaik, Resample To Image filter does not support -1 as a parameter for sampling dimensions.

Hi Mathieu,

attachement was indeed missing, sorry about that. The same thing happens for a direct import of an image volume.

Would adding this support be difficult? it’s quite useful for me as I have multiple volumes coming from multiple sources that do not match, and I may not have access to the pre-process of each volume to change their orientation.


You mean -1 in the transform of the representation !
Indeed, it does not seems to work with volume representation, definitely a bug.

You are welcome to open an issue on our gitlab :

FYI, contribution are very welcome.

Yes, in the transform, I wasn’t clear enough.

OK, i’ll open an issue in the afternoon, thanks for you reply.

What kind of contribution do you mean? in the bug reports or in the bug fixes?

All are welcome : issue reports, issue investigation, bugfixes and merge requests :slight_smile:

Sure, i’ll definitely try to get more involved in this. But I guess I’ve got to sharpen my C++ coding skills for the later ones.

Are you working with the 5.6.0 release ? I see this issue only with a builded master.