Brush types, paint types, etc. - random thoughts

[Matthew Woehlke]

Since we've wandered off into the Weeds of Theory, I thought I'd toss 
out a few thoughts on homogenizing various real media tools. Maybe I'm 
way off base, maybe Krita can never do this, maybe this is 3.0 material, 
whatever. I'm just throwing it out as 'stuff to think about'.

The way I see it, you draw/paint with two types of material... brushes, 
and sponges. Both have properties such as density (both size and 
frequency) and stiffness. For brushes, this should be fairly intuitive; 
density means number and size of the bristles. For sponges, density 
means how big the holes are, and how much of the 'painting surface' is 
holes vs. empty space. Pressure on a sponge usually increases the 
frequency-density.

This seems to cover most types of drawing implements.

I know, you are screaming "what about pens, pencils, chalk, etc?". Well...

A pencil is a very tiny chalk which is a sponge, usually with very high 
frequency density and maximum stiffness. A pen is probably a fully-dense 
sponge with moderate stiffness, although a one-bristle brush might work 
better for some types of pen (e.g. a quill?).

(Ok... this covers *contact* tools. Airbrushes are of course totally 
different. Also, a 'squirt' tool comes to mind...)

The rest is pretty much covered in the paint type, the main 
characteristics of which is wetness/dryness. A "wet" paint (watercolor, 
for example) will run much more and be more easily manipulated with 
water, while a dry paint (which would also be carbon, chalk, etc.) won't 
run at all.

Application is then affected primarily by two characteristics; paint 
wetness/dryness, and brush stiffness. A dry paint will tend to stay put, 
while a wet paint will settle into valleys, and a medium paint will tend 
to give more even coverage. A stiff brush will tend to deposit paint 
mainly on peaks, while a flexible brush will provide more even coverage.

-- 
Matthew
If you can read this, you're too close.