improved mirroring

[barrettMCW]

Fixed the jitter from panning while rotated, and it seems at some point in the pr process drawing the rois while mirrored broke. Fixed it up. Still couldn't get projections to work. I do think that would be the most robust way to handle this but I'll take another crack at projections next time something breaks. Thanks y'all!

[will-moore]

Thanks for this - apologies for the delayed response.
It's working nicely and fixes the crazy jitter on dragging when rotated. It also fixes the ROI drawing when flipped.
However, the dragging of the image when flipped is opposite to the expected direction (the flipping is not taken into account to reverse the direction of drag).

NB: I also found it a little tricky to know when the image was flipped as there's no indicator. This is outside the scope of the PR so no need to address it now unless you want to, e.g. add some visual clue to the flip buttons when they are enabled?

[barrettMCW]

That's strange... I added a mitigation specifically to fix that on my end line 80

Can you give me some more info about how you're testing it? I'm viewing it with npm run dev on chrome.
I like the flipped indicator idea! I'll add it quick.

[will-moore]

That's weird. I'm building with npm run debug or npm run prod then opening iviewer from webclient.
However, if I use npm run dev then I don't see the bug (same as you).

[barrettMCW]

added flip indicator, not pretty lol but distinct between flipped and not flipped.
the prod vs dev is a real head scratcher though, I'll keep looking into it

[barrettMCW]

Think I might have gotten it figured out? I was looking at the name of the constructor which gets minified in prod. Hopefully that was it, I don't have an easy way of testing this out, let me know if it's still an issue then I'll set up a proper dev environment to test this more thoroughly.
Thanks!

[will-moore]

That's fixed it - thanks!
Looking good - approved.

I noticed one tiny issue which I'll mention in case you can find a fix (but isn't a blocker on this PR which already has plenty of fixes)... The blue rectangle that appears when you hold Command-drag to select a bunch of ROIs is flipped on the screen (although the ROIs are correctly selected from the area that was actually dragged over).

[barrettMCW]

Great catch! Thanks! (didn't know you could do that lol) It's mostly fixed. It captures extents properly but for whatever reason it doesn't render when only X is mirrored. When just Y or X and Y are mirrored it works perfectly but X is misbehaving. Still captures properly so I think it's better than it was.

[barrettMCW]

Still haven't figured out roi popups yet. I'll skip that this PR, but if there's anything else you find, let me know. Thanks!