Re: BA Volume texture deformation?

["peter boeykens" <peter_b(at)skynet.be>]

I have done exactly this - for a tornado seen from space.

If I remember correctly I had a flattened and subdivided cube, and used a volume deform to twist it horizontally in the center, avoiding intersections, and making sure the volume remained a perfect flat cube!

Then used a fractal (simply mapped with a frozen planar projection) to drive the min/max height of a vertical gradient that drove the density of the BA_volume.

I first thought of deforming the texture space but didnt get anything usefull out of that.

Then I tried to have the fractal directly drive the density and that didnt work well either, since the volume shader likes implicit projections and you cant deform those.

The vertical gradient was what did the trick really, it was driven by the y component of a vector state set to intersection point. That gave it the nice volumetric look.

 

Hope it all makes sense?

 

 

I am doing a sort of vortex - not a tornado but something a bit like it in nature. It needs to be rendered with volumetric fractals where the BA shaders fit the bill. Now my problem is I'd like the fractals texturespace to deform with the geometry which is basically a cylinder which is twisted, rotates around y and then curve deformed so it can move about some. I have tried different methods and orders of deformation, but so far no go. How do I deform a spatial texture support by its geometry deformations or is that just not possible?

 

Morten Bartholdy
3D & VFX Artist