When visualizing image cubes, Glue’s image viewer extracts axis-parallel slices through the data. You can also extract slices from arbitrary paths through the data, using the slice tool in the image viewer:
Activate this mode and click (or click+drag) a path on an image:
Hitting escape will reset the path. Hitting enter will extract this slice from the original cube, and display it in a new window:
The slice plot is linked to the original image viewer (of course!), so that click+dragging on the slice window will update the orientation of the image window.
This video demonstrates the process, and also shows the power of combining slice extraction and spectrum extraction.
This kind of slice extraction is especially useful for spectral cube analysis, since the extracted images are position-velocity diagrams. However, they can be useful in other contexts as well. For example, here’s a screenshot showing an on-the-fly cross section of a brain tumor MRI:
The script used to load this data into Glue can be found here.