Features in color smudge
Dmitry Kazakov and i talked in irc about some things to be improved. i was personally missing these features in color-smudge and i explain why
He provided me this special release https://yadi.sk/d/Rr3sK2fsQ87YDw with 2 new features added in color smudge engine. Ratio and Airbrush.
I have published in Krita Artist to see if this looks interesting to the community. https://krita-artists.org/t/new-color-smudge-features-for-next-release-wip/3667

Ratio
I use Ratio to compress the brushtip in some cases. But I see the limitation of not being able to choose what angle i want to use. X or Y. Also I notice that antialias is more evident when we use Ratio compression with a high value than when we use a brushtip that looks stretched. so if Ratio is not controlled by curves it is better to use brushtips with the desired shape.

Example. What can offer a triangle? Screenshots will go here. WIP

Airbrush
I use a lot this feature in watercolor brushes to mimic some kind of interaction and buildup between stamps. That with changes in opacity and flow curves produce different effects
Masked Brush
I don’t have idea how much time involve this but i use a lot the Masked brush as i shown in the RGBA brushes video and also in Digital Atelier Brushes, specially for Watercolor and Oils.

Overlay Mode
This mode is useful but lags and makes the brushes slower.

Testing AREA
First tests are awesome. Results with this new feature added. I like how some parts of the painting are moved or translated to another area. This creates interesting shapes. When you add spray you multiply this effect a lot . Totally love it. Good job man. I have recorded 2 short videos to show the behavior. (Last one has a sound like darth vader, sorry i forgot to change an adjustment. As these are temp videos and short, here you have.)

Today i have been testing with some kind of oils effects. is good to see the interaction between colors.

If you are interested, now is your turn

ADDITIONAL NOTES:
What makes a good Oil brush?
After a lot of testing and brush making I have in my mind like some guidelines to get nice brushes. Other artists can think in a different way. Each one has a unique workflow. I would say that brushes can be divided into 5 pillars.
Brushtip
It gives the user the traditional media feeling. Digital Atelier has brushtips for that purpose.
Lately i am thinking in a way to create animated brushes for that purpose.
Brush Settings or Brush behavior
You have to balance beauty of the brushstroke and performance. When you activate Pattern or masked brush specially you notice how performance decrease. Obviously is understandable due the computation, but some people can rant then.
Pattern used to recreate the surface feeling
If we use better patterns the feeling of surface improves. Creating a good pattern is not an easy task. tileable or seamless feature without loosing quality is important.
When we use 1024px x 1024px patterns we get some lag if we adjust the parameters in the brush editor. 512 px x 512 px is good.
FX applied to the layer. With filter Mask or layer style.
Layer Styles are quite slow
Fx in layer are a bit faster

Blending mode in brush tool

• Oil painting: normal
• Watercolor: Normal, Gama Dark, Multiply, Greater
• Pastel: normal
• WaxCrayon: Normal and Darken (color smudge) WIP.

Fields to be improved
We have impressive features and people is discovering more and more about Krita.
Patterns
They are used as “Static” patterns. I showed in a video how infinite painter can distort that and that makes interesting effects to simulate variation in the brushtip. Fixed, Rotate, Warp
It can be used a bit as we use masked brush feature. https://drive.google.com/open?id=1uIwLi--4FCeHa2kNSnm_izTz5-17Gu7k