Patch: Smudge Brush fixes

[JL VT]

Silvio, I downloaded your patch and added it to a git branch called

krita-fixsmudgebrush-silvioheinrich

It's available in the remote repository (the master) such that others can
check it out and play with it.


I noticed a problem with your version of the brush, slightly transparent
colors quickly become opaque:
http://imagebin.org/132048

That doesn't give the impression of smudging very much. This is a problem
the old brush had to an extent, but it was mostly about the darkening (with
black).

I am also having difficulty replicating the "look" of the old smudge brush
defaults. Can you try to tune the defaults of your new brush to look as
identical as possible to the defaults of the old smudge brush?, this will
help avoiding unfamiliar behavior.

I also want to ask you why did you remove this part of the code? -->

        // Both limits defined to be 15 units away from the min (0) or max
(255) to allow actual mixing of colors
        const quint8 MIXABLE_UPPER_LIMIT = 240;
        const quint8 MIXABLE_LOWER_LIMIT = 15;

        /* Without those limits, the smudge brush doesn't smudge anymore, it
either makes a single
        dropplet of color, or drags a frame indefinitely over the canvas. */
        opacity = qBound(MIXABLE_LOWER_LIMIT, opacity, MIXABLE_UPPER_LIMIT);

Is it because you put the limits in the controls or the GUI, or is it
because you deemed it unnecessary?