With Krita 4.2.2, the Liquify tool makes pixelated transformations, or fuzzy ones. I haven't tried another 4.2.x versions.
I tried with the 4.2.1 & 4.1.7 version, the same kind of transformations makes much more clean and smooth transformation.
It seems there is a regression. Can you confirm ?

Hm, I can't say I actually can see any difference, but my eyes are notoriously bad. The only thing remotely relevant that changed was the nearest neighbour scaling algorithm, but liquify doesn't use that, afaik

It does look that way going from 4.2.1 to 4.2.2, testing with the appimage version. I was careful to use the same mode and parameter values in both cases and tried to do the same 'sweeping ' action through the original straight line. There is pixelation in the preview but this disappears (mostly) when the transform is applied.

Here are two screenshots of the applied transform, superimposed, showing use of 4.2.1 to the left and 4.2.2 to the right. There is roughness on the edges with 4.2.2.

I made same kind of liquify transformation on same file, on time with 4.2.1, one time with 4.2.2 (app images). We can see differences.
(Nota : If it is a bug, do I have to report it, and where ?)

Please make a bug report?

boudewijn wrote:Please make a bug report?

Can you tell me where ?

The formal bug reporting system is here: https://bugs.kde.org/

You need to register then sign in to create a bug report or add comments to other bug reports.
You can add your images as attachments to your initial report and any additional comment posts you make.

Please reply in this topic giving a link to any bug report you make.

Bug report is here :
https://bugs.kde.org/show_bug.cgi?id=409280

I close the topic.
Thanks for your fast responses !

Ghevan is looking into it right now

Krita fever, Krita for ever

Courage for all of you.