Aye, thought so. Can't remember the name of the thread either, just that it was a long one. I think it might have been started to find a way to make a tornado's funnel shape.
As for my new idea, all I got was tripped at the very first step! I figured to take a Get Normal in Geometry or even just a Visualise Normal shader node, then convert that to a vector, and finally Vector to Colour, to use as a cloud's Final Density Modulator. Simple, eh? Haha! Anyone see the one minor error I made? ... ... ... Yup! You can only plug an object output node into a couple of select things, populators and renderers, so there's no way to take the normal of the shader after it's applied to the object, only before. Doh! :/
However, after the first facepalm moment, I spent(wasted) hours and HOURS trying out a new method, that I still do think has some merit, maybe you guys can help? I figured this time that GI would be a great way to light a volume, via an object's surface that is luminous but invisible to the camera, good eh! Made good progress with that but, ultimately, I think a horrendous GI/ray detail setting would be required to make it take the actual object shape from its luminance. I tried everything I could think of yesterday, got a good glow in the volume from the hidden object, but no well defined, hard GI-light edges... Started now on the opposite track - Shadows instead of light, I'll report back with any developements. I still really think there's something in this GI thing, though, I'll mess around some more when I have time...
