Whilst working on my "Worlbowl" image I've noticed that due to
the change of perspective, the individual disc which make up the
clouds inside the bowl itself are easily identified. Since this image
will ultimately be traced in a fairly high resolution, that effect will
be even more visible then.

So I've decided to move from stacked-planes, a rather old technique,
to scattering media. I've got some relativ good experience using media
for clouds (I've very satisfied by some of the comments I got for
"Iced Land") and can find my way around modifying the brightness
and extinction and such to fit my needs.

I'm rather curious on how I might be able to convert the texture-driven
density from the stacked-planes to one I might use with my media,
as several effects (like clouds diminishing in size as reaching upwards)
could be done fairly easily with texture-mapping and color-map access.

My first guess would be to take the texture, create a density-macro off of
it, and then use gradient to move from one texture to the next. I'll try it
as a first attempt when I've got the time to do so, but I was curious if
others have tried something similiar, or got a better/other approach to
achieve what I am trying to do.

Regards,
Tim


--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

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So, took some time and was some effort to get the
density behave like the stacked planes, but the result
is much more smoother and easily altered in how the
light is scattered etc, that it was well worth the effort.

Doing this I've found that applying some effects from
texture-mapping to density-scattering is quite useful,
I'm thinking about creating some sort of easy access
for this kind of media-interaction, but that'll take a while.

Those interested might give a note and state some features
they'd like to see, so that the result might actually be of
some use. Please note that I'm not into functions, though
that's definitely on my to-learn list.

I've also stumbled across the issue of multiple scattering
containers overlapping, which results in darkening of scattering
media on overlapping parts. I've just put both medias in
one container, which doesn't have the same nullifying effect,
though scattering parts will obviously add to each other.
Higher absorption takes care of that, in case anyone wants
to know...

Regards,
Tim

PS: Other suggestions on how to model clouds are welcome,
I'm interested in how this might be achieved differently!

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

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