Watertight nurbs geometry.

[BigSky]

Do you mean your joins between 2 patches are misaligned?
If the isos line up, and you have done a global stitch (or whatever method) they should be okay. What might be a problem is that your surface tesselation may not be cutting it at rendertime. Go into your surface shape node, and check display render tesselation, then, use (optimized) best fit for your shot.

[sanex]

Thanks a lot for your Suggestion :). But I am still confused about open holes at the end of the model.
Even you can find out those holes on Default Nurbs sphere.

My question is there any tool or any method that we can fillup these holes for watertight geometry?

[BigSky]

Can you post an image? Watertight...do you mean some kind of "solid" object? The reason I ask is that nurbs are basically rectangular patches with maths in. A sphere is a rectangular patch, pinched at the top and the bottom. All nurbs surfaces, given they need a U and a V direction, are composed like this.

[sanex]

Thanks again BIgSky:) .
Yeah, "solid" object. I am uploading the image. you can see the open hole at the top of the model.

[BigSky]

Well, you might consider a rebuild of your surface to even out the paramatization, but to make it a "solid" (and it never really will be...) you can insert an isoparm at the top, and then scale a hull to 0, then snap the points of the hull together. (ie all the cv's are sitting on top of one another). Getting some clean geometry will help you no end in this regard.

[sanex]

Hey, I got the solution on cap holes, But not in maya. I opened the maya file in "Rhino" which is the best software for Nurbs( I think so). you just have to select the whole model and there is a tool called "Cap Planer Holes".Fixes it right up.and it fixes open edges also.But after that it becomes "solid" mesh which you can't import in maya.


And again Thanks a lot for your support BigSky:) .

[beaker]

I think you misunderstand how nurbs work. Nurbs works kind of like how you build stuff in real life in product design. Everything is built out of little sections or patches. When you build a tube the outside is one piece, the caps are another piece and the inside of the tube is also a separate piece. You build things by making contour curves and lofting/birailing sections.

Tom Capizzi has some cool stuff on his site about nurbs.

http://www.tomcapizzi.com/vfxWorld/char/pg04.html
http://www.tomcapizzi.com/vfxWorld/char/pg07.html

This tutorial is the one I learned from back in 96 when I was using studio tools/power animator.
http://www.tomcapizzi.com/imagesHi/headWebPage/index.html

Also this WRX tut will show you how to use nurbs properly with a hard surface model.
http://www.blissdd.com/WRX/Tutorial/tutorial.html

[sanex]

Thanks Deke,

These links will really work for me;).

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.