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View Full Version : modeling: how to make low poly screw thread?

Iggy
09-04-2003, 09:29 PM
I'm animating a scene that has multiple threaded pieces including several pieces of threaded rod. I've found several ways to make accurate threads but they are really high poly count, especially on a long piece of rod. Is there a way to fake it? Perhaps a bump or displacement map technique that tiles down a cylinder? I will probably not be up close to it... My knowledge of materials is pretty poor, so I don't know if this is realistically possible or how to begin. Or perhaps there's some other way to cheat it? Any direction would be greatly appreciated.
Neoklassik
09-04-2003, 10:02 PM
A extruded helix spline should give you a good amount of control over the subdivision and point interpolation. Just run the cylinder through the helix. You could make instances if it's extremely long for sections.. but if you're going for just a hint of detail I'd just suggest a pattern or a bump map.
Iggy
09-04-2003, 10:14 PM
Yah, I've built some threads by sweeping a tri spline along a helix. They look great, but poly count gets high very quickly, even adjusting subdivisions down. Since it's going to be animated and there will be several in the scene I'm trying to cut it down. Not to say that I can't use the swept version, but if I can avoid it I'd like to...

What I'd like to know is how to do it with a bump or displacement map, being a noob at such things... How do I build such a map in such a way that it will tile correctly with cylindrical mapping??
AdamT
09-04-2003, 10:14 PM
Another method is to create a subdivided plane and move every other row of points in the Y direction. Then put it in a bend or wrap deformer.
Neoklassik
09-04-2003, 11:23 PM
"Yah, I've built some threads by sweeping a tri spline along a helix"

Hmm yah I think a sweep will add unnecessary polys. I was suggesting a extrude - see link

If you want to use a bump map just go into Photoshop and create some angled diagonal lines for your texture.

http://www.3dfightclub.com/~neoklassik/uploads/threads.jpg
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