I have no Idea how this would be done without using lots of tiny particles,
and even then Icouldn't give you much of an Idea of how to write such a macro.

Maybe you should try Megapov's Mechsim function, it might give you the desired
effect.  you could write a recursive distribution macro.  something that would
randomly distribute the particles throughout a given area (translate <randx,
vector_supplied_by_mechsim+particle_radius, randz>).

I don't know, maybe this is totally crazy, I haven't worked much with
MegaPov.  But the only other thing I can think of is writing your own gravity
sim to make the distributed particles fall until the trace macro detects a
surface.

A.D.B.

Vladimir wrote:

> the dust I would be moddelling would be on the upper surfaces of objects -
> airborne dust can be pretty well simulated with media. The one thought I
> had would be this: Is there any way to create a loop that distinguishes all
> surfaces facing in a single direction or at least partly in a direction ie
> set to pick up y facing surfaces would also pick up the line x*y. Dont know
> whether that makes sense. It would then add a semi transparent layer on top
> of the current texture. Im not sure how I would go about writing this or
> even if it is possible in povray.
> Peter

Post a reply to this message