Hi,

I am wondering whether this is a bug. I found that strange silhouette appears whenever painting with Color Smudge Brush over the soft edges of existing color covering the transparent area on a layer.


The problem can be replicated by the following steps with a Mix_dull preset brush ("Color Smudge Brush" with pressure sensitive "Smudge Length" & "Color Rate" enabled in "Dulling" Smudge mode):
1. Create a new empty layer
2. Paint a stroke with fading ends

3. Paint another stroke with a different color over the fading edge of previous stroke

A strange silhouette of previous stroke then appears. More obvious result can be obtained if the colors of painted stroke and underlying color have larger difference in instensity.

Besides painting with "Color Rate" enabled, I have also tried smudging from existing color with "Color Rate" disabled, and I got the same result.


This strange behavior never happens when blending color at non-transparent area even it is not completely opaque, but always happens at the area with color fading to completely transparent.

It seems the opacity blends correctly but the color does not. I tried to proof this by locking the layer's alpha and painting another color over the strange silhouette produced by Color Smudge Brush. The strange silhouette disappeared and smooth shade left.



Though it is not obvious, "Smearing" Smudge mode seems to have the same problem as "Dulling".

(Paint with "Color Rate" enabled)


(Smudge with "Color Rate" disabled)


(Paint another color over the affected strokes with alpha locked)



The problem exists in both Windows (7 Pro x64) and Linux (openSUSE 13.1 x64) versions (Krita 2.8.X).

I found the Color Smudge Brush is irreplaceable for painting natural and analog like strokes. Working with MyPaint and Krita together is just too tricky. If there is a proper blending brush, I can paint comfortably from start to finish in Krita.

Any help would be appreciated.

Yes, there's a couple of bugs in the colour smudge brush. There's plans to fix them, of course, and if not fixed beforehand, they are on the priority list for the sponsorship drive!

Edit: Here's the bugreport: https://bugs.kde.org/show_bug.cgi?id=333227
Don't feel shy to sign up and add your own observations.

Thank you TheraHedwig.

I just added my observations to the bug report.
I have also filed a new bug (for the first time in my life ) regarding another strange behavior of smudge brush here: https://bugs.kde.org/show_bug.cgi?id=334538
It is great to hear that the fixing of smudge brush is on the priority list! Having more features is definitely good, but I think a flawless smudge brush is the only tool that is critical to complete krita as a painting software.