Re: BA Volume texture deformation?

[pingo van der brinkloev <xsilist(at)comxnet.dk>]

Hey Morten. I dunno if you solved this but you can do it with the XSI enhance shaders. There's a vortex coordinate distorter. You can do some math with Holgers Mesh distance, as he sais, and subtract some noise with the vortex on. just model a simple "tube". doesn't even have to be twisted. use a hit point and you can rotate the whole "cloud" system.

ok that's confusing. Like this

BA_meshdistance 

> BA_simplemath(subtract) -> BA_VolumeCloud -> Material (volume)

HitPoint -> vortex -> noise 

Call me if you need more info. I've made one and it works.

pingo

On 03/04/2008, at 10.49, Morten Bartholdy wrote:

I meant an implicit texture...

 

----- Original Message -----

From: Morten Bartholdy

To: XSI(at)Softimage.COM

Sent: Thursday, April 03, 2008 9:51 AM

Subject: Re: BA Volume texture deformation?

Thanks Peter - those are my observations too - I can deform 2D projected textures but not a spatial one, . I would just like to apply a spatial projection and have that deform with my geometry. Like you say I need to deform an explicit projection like with a lattice or other deformers, which seems partly possible only with the new Texcoord feature, which Holger points out. I guess I need to upgrade now - I am still on 2.1

 

Morten Bartholdy
3D & VFX Artist

 

----- Original Message -----

From: Schoenberger

To: XSI(at)Softimage.COM

Sent: Wednesday, April 02, 2008 1:05 PM

Subject: RE: BA Volume texture deformation?

 

One thing you can try is the BA_Texcoord:

http://www.binaryalchemy.de/develop/clouds/vid/Volume_Texcoord_grids.mov

Check the sample scene.

 

Get a grid (converted to triangles, planar projection, freezed) on the right side and exactely the same on the left side of your cylinder.

(I assume your twist is bottom to top)

If you cut your object horizontally, you get a planar projection, but from bottom to top this projection rotates.

 

Otherwise it would only be possible with some maths in the render tree. I am not sure if you can use the XSI edit_coord (or similar) and drive the rotation vector by an input shader.

Holger Schönberger 
technical director
The day has 24 hours, if that does not suffice, I will take the night

 

---

From: owner-xsi(at)Softimage.COM [mailto:owner-xsi(at)Softimage.COM] On Behalf Of Morten Bartholdy
Sent: Tuesday, April 01, 2008 5:26 PM
To: XSI(at)Softimage.COM
Subject: BA Volume texture deformation?

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