I cannot reproduce the "bug".
But it is not realy a bug but correct. If you do not reinit on brain.nrrd before making the planar figure, it is tilted. Therefore no statistics can be computed.

When I do this:

• Open brain.nrrd
• reinit nrrd
• Draw a planar circle
• Try to select both in image statistics

everything works.

@nolden have you done a reinit before using the statistic?

With a reinit it works but boy is this unintuitive for users. Like when starting the Workbench and opening brain.nrrd, there's no indication that a reinit is necessary (and what a reinit is and where to find it is another story). You can draw a planar figure on it just fine.

I just tried the Segmentation view as it should have similar issues but it does automatically reinit the image. Maybe the Measurement view should do it like that as well?

Hm, yes, As we also define a reference image like in the segmentation view. I think it is the most pragmatic and consistent approach to introduce the same/simelar behavior:
warn users if the rendering is not alligned with the reference image and only allow making planar figures if the geometry was reinit.
I am not sure if reinit as soon as the click on a planar figure button wouldn't be irritating.

We should clarify how we handle the reinit or reinit warning in the Measurement view. Should be very simelar to the Segmentation view.