Show top-down atlas coverage during alignment #12
Description
It would be rather handy to know where / how much of the atlas you've covered while aligning.
This allows the user to eyeball whether what's been covered on the atlas matches what they've sliced, and also acts as a quick QA for the user to know whether they're overaligning slices to a particular point on the atlas (some structures can be pretty same-y).
I'm thinking of a top-down projection of the atlas with a boolean slide aligned etc.
Not urgent, this is a would-be-nice-to-have.