Long brush dabs in SPainter ?

Or only square ones are possible?  

I mean something like in corel painter , 3d coat , zbrush and lots of other soft where you can take a photo of long more or less straight seam or crack, make a brush from it and then you can paint it having each stroke starts from random V value ? Having extra start /end dabs if necessary , alternate to another long dab ID at certain V point etc.

Never looking repeating or artificial .

I hate square shaped brushes , either in Photoshop or elsewhere , they always look fake whatever random things you put over .

My guess it should be possible now with pen curve based strokes at least , right ? like in almost evry vector soft . Have anyone managed to do one?