GIMP :: Simulation Of Real World Painting

I mainly use MyPaint, Gimp and Inkscape, but I also made a quick tour ofother painting softwares. If all of them take into account the color (asis, without any characteristic like viscosity, nature of a paint - oily oraqueous) and the toools to apply the color (with a stiking inventivenessregarding the brushes !), I have not found any that directly simulate thebehavior of the media on which the color is applied. However, to take justthe example of the watercolor, the paper has a fundamental importance onthe effects that can be applied and on the final rendering.

Of course, with a good expertise - and dexterity - in a particularsoftware, one can, by manipulating the image, achieve a very close if notidentical result. But this is akin to a Grand Chef cooking, with secretrecipes, tricks and tips, subtle dosages...

why the medias are not implemented in the paintingsoftwares ? There is some few basic parameters as the substrate porosity,surface roughness, anisotropy of the porosity and/or roughness, inclinationof the surface of work, and if this is coupled to some parameters of theink, like viscosity, attractive or repulsive power of the ink, you can workreally more intuitively.