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upstream
10-30-2006, 01:50 PM
I'm working on a series of 3D illustrations of geological rock formations.

One thing I have used successfully is procedural shaders. This has allowed me to create and infinite number of colors, textures and layers in a formation easily (Fig. 1).

Fig. 1
http://www.ranainteractive.com/images/fig1.jpg


However, if your working on a more complex formation, anything other than horizontal or angled layers of rock, this technique falls short. The easiest way I have found to get the exact formation I need, is to model it and texture the layers separately. This also works well with the same shaders I've been using (Fig. 2).

Fig. 2
http://www.ranainteractive.com/images/fig2.jpg


I only have one problem. Most layers of rock are made up of other fractured layers of the same material (Fig 3). It's easy to get these perpendicular cracks and layers using the bump and diffusion channels in the shader. But, the texture also needs to follow the geometry (the layer of rock), unlike my sample above (Fig 2), where layers I've added to the grey rock are horizontal.

Fig 3
http://www.ranainteractive.com/images/fig3.jpg


Does any one have any idea how I might get the textures I create in the shader to follow the geometry I apply the material to?

Or any other ideas (texture maps, Bodypaint, etc.) that might work for this type of project?

Thanks,
John
Srek
10-30-2006, 07:29 PM
How about not modelling the shape but deforming it from a box shape with Bend deformers? That way the UV mapping would remain intact and follow the deformed contour correctly.
The othe roption is to adjust the UVs to the flow of the shape, but that would be much more work imo.
Cheers
Björn
upstream
10-30-2006, 08:04 PM
Björn,
Thanks for the reply... I'm really new to this, could I still use the same volumetric shaders that I'm using now with ether of these techniques? Any other info you could point me to would be appreciated.

I found a lot of great info on the personal site a few weeks ago while working with TP. Thanks for the effort there as well.

Regards,
John
LucentDreams
10-30-2006, 08:15 PM
yea modeling with nurbs, or using straight surfaces that you then deform into the appropriate shape would be best ways to get the texture to lay properly.

Using nurbs the textures will just work automaticlally no fiddling.

With a flat shape that you then deform (I'd use FFD more likely than bend btw) you'll need to turn off the deformers, apply the material, then apply the texture on UVW space. if the UV is junk and you use a different projection type and use whats called a stick texture tag. Then turn deformers back on and your good to go.
Srek
10-30-2006, 08:22 PM
Unfortunately this will not work with volumetric shaders. You will have to use normal materials with channel shaders to create the needed look.
Cheers
Björn
vid2k2
10-30-2006, 10:16 PM
You could also modify what's been said by using a cube
to the length and width with appropriate Z segments.

-push pull Y points for the wave
-drop into a HN cage
-select edges- and weight them
upstream
10-30-2006, 10:30 PM
David,
That's what I'm looking for... but, I don't know enough to understand your explaination. Can you give me more info, a tutorial or a .c4d to look at.

Thanks
vid2k2
10-30-2006, 11:13 PM
Here's another sample using banzi.
Youll see how I structured the file,
it's really easy. Glad to help out :)

File attached for both.
upstream
10-30-2006, 11:49 PM
That did the trick and allows me to use the shaders I've already set up. It also helps solve a couple of other problems I had, with even more complex formations. Thanks for all of the help.

John
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