Quoting blacktoon <for...@gimpusers.com>:
> I found s.th. like a mistake in gimp, is this a already well-known bug?
> I described it here:
Not really a bug. You are misconstruing the action of the Smudge Tool.
GIMP's smudge only smears the colors that already exist on the canvas;
whereas it appears that MyPaint introduces some amount of the
foreground color to the start of the smudge operation. Without
introducing new color to the canvas, the laws of entropy dictate that
repeated application of the Smudge Tool will have a dimensioning
effect (this is what you describe as the canvas being "frozen").
Your assertion that "every other image manipul.app" behaves like
MyPaint is not to my knowledge entirely accurate. Coral Painter
behaves the same as GIMP; and Photoshop's default smudge behavior is
identical to GIMP unless you choose the "Fingerpaint" option (which
makes it behave like MyPaint).
Perhaps you wish to propose enhancing GIMP's Smudge Tool by adding an
option to introduce some amount of the foreground color at the start
of the smudging; but until such an enhancement is supplied, a ready
work-around is to manually paint a spot with the paintbrush and then
switch to the Smudge Tool to smear that spot.
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