Intuitive selection

[mbaeuerle]

This PR will introduce a new way of how crop rects are selected.
Prevously:

• Resizing a rect was possible without being selected
• Selection/deselection was done with ctrl + click
• Moving and scaling multiple rects synchronous was only possible while holding shift

With this PR:

• Clicking on a rect will select it
• Shift + click adds a rect to the selection (or removes it if it was already part of it)
• Deselection of all rects is done by either
  • clicking anywhere else but the selected rects
  • pressing ESC
  • A new selection is started by clicking on a rect which was not selected before (without shift)
• Moving and scaling multiple rects synchronously is now done without a modifier

I think that is a more natural way for selecting objects, less cumbersome and is also more familiar from other tools like Powerpoint, Keynote, etc.

[cleydyr]

Hey, @mbaeuerle . I've made just a comment in the PR with a suggestion. Other than that, it looks good to me.

Regards

[mbaeuerle]

@cleydyr thanks for reviewing. Maybe I'm a bit blind today, but unfortunately I could not find your comment. Maybe it's still pending?

[cleydyr]

Didn't mention you. 🤦 I thought Github would notify you anyway. Fixed.

[mbaeuerle]

@cleydyr Still cannot see any comment 😮 if you started a review (instead of writing a single comment) you need to submit it first before I can see it. Otherwise the comments are still in pending state.
https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/reviewing-proposed-changes-in-a-pull-request#submitting-your-review