Show affected area in Clone Tool?

[davidh]

I was wondering whether it would be feasible without much intrusion into already quite complex Clone Tool to have a feature to display sort of affected area. Kind of resulting static (ON/OFF) overlay on the input image where any change was made.

This feature would be useful especially with subtle changes where Lighten only and Darken only were applied. It is often difficult if not impossible to locate such changes retrospectively by viewing input and output in the split preview.

Maybe something in the way of the Show affected region checkbox of Selective color transformation, or show input minus output image checkbox. No history of cloning, nothing synchronized with touches, just the current state of changes when switched ON.

Of course the "minus" of Compare transformation can be used, but this means an extra transformation just for a simple check.

[jsachs]

While you can also flip back and forth between the input and output image to help identify which areas have changed, I do see the potential value in what you are suggesting as well.