v50

[B.Douille]

the undo stores all changes even on same adjustment. I found 'undo' confusing, because the tool are applied always in the same order. It's not a stack of actions (you cant have the same adjustment more than once), its to have a real time preview.

I agree, the fact the undo/redo buttons stores all changes step by step accross all adjustments can be confusing. That's why I suggested to highlight the corresponding button for each steps back and forward (the adjustment that was changed at the particular step).
It means, if the user change it all following steps should be cleared.

[xnview]

so for example, we change:
Exposure/Gamma/Saturation. undo => Exposure/Gamma, undo => Exposure, redo => Exposure/Gamma
Exposure/Saturation/Gamma. undo => Exposure/Gamma, undo => Exposure, redo => Exposure/Gamma
or undo => Exposure/Saturation, undo => Exposure, redo => Exposure/Saturation
??

[B.Douille]

Exposure/Gamma/Saturation. undo => Exposure/Gamma, undo => Exposure, redo => Exposure/Gamma

Undo follow the same path, the sequence in reverse order.
Redo re-do the last so still the same path but in same order the user did originally

[xnview]

Please check v54

[B.Douille]

Looks good, better
Is it normal that on the way back (undo, undo,...) the values are all zeroes. And when pressing Redo the values appears as they were ?

[xnview]

Is it normal that on the way back (undo, undo,...) the values are all zeroes. And when pressing Redo the values appears as they were ?

??

[B.Douille]

I change in this sequence :
- Exposure +5
- Saturation +12
- Contrast +8
- Brightness -15

Undo Brightness 0 (?)
Undo Contrast 0 (?)
Undo Saturation 0 (?)
Undo Exposure 0 (?)

Redo Exposure +5
Redo Saturation +12
Redo Contrast +8
Redo Brightness -15 and I can readjust

[xnview]

I change in this sequence :
- Exposure +5
- Saturation +12
- Contrast +8
- Brightness -15

Undo Brightness 0 (?)

yes, undo remove the last tool. not what you expect? or you want to go back to contrast tool?

[B.Douille]

undo remove the last tool

You are right, that's the typical behavioral of Undo/Redo. I didn't realise, it just made it obvious

However, did we lost part of the history ? If I change Saturation +12, - Contrast -1, Saturation +10 and I go back I expected to see Saturation +12 at some point

[xnview]

However, did we lost part of the history ? If I change Saturation +12, - Contrast -1, Saturation +10 and I go back I expected to see Saturation +12 at some point

like i said before, only 1 adjustment is applied (to have real time). So if you change Saturation +12, contrast -1, Saturation +10, the process will be Saturation +10, Contrast -1

[B.Douille]

Ok. I was in the impression the Undo stack could store more than one occurrence of a single adjustment. No.pb.