Hi PaQ,

> (I was thinking that every rendering engine have to
> tesselate the nurbs model :)

I guess it kind of depends on what your exact definition of tessellate is...

But the REYES / RenderMan style approach is to subdivide NURBS surfaces into smaller and smaller pieces until you get pieces that are smaller than a pixel (a "micropolygon").

So it kind of does tessellate because there is a conversion from NURBS into polygons, but on the other hand it is a different style of tessellation than the conventional kind of mesh conversion because it happens to a level of detail to where you can't see any evidence of the polygon conversion...

- Michael

I'm playing with the demo right now (air space), not super intuitive, but there are a lot of doc to read :)

Thanks for the link !

> Indeed Michael, that's what they seems to call geometry tolerance in the settings (you can drop to 0.25 pixel) ... well ... I like the idea :)
I know the technique for micro-displacement map, but I didn't know it was used for rendering nurbs ... learning new stuffs everyday !

And yes, I also wish that more engines could support NURBS directly. Even better if they can render NURBS directly without a render mesh. AIR (for Rhino) supports this and it's really so cool. But AIR is a RIB renderer, not sure how modo could support that feature. Unless of course Pixar wants to share that tech with Luxology... :)

jonah

 


PaQ wrote...
"Well I suppose it's quiet hard to give this kind of compatibility between two software, more over when it's about shading stuff. I mean modo shading tree can be quite complex already and I'm really not sure Rhino can handle stuffs like layers mask by object id for example, something really typical from modo ... or stuffs like vector displacement map.

I'll be really happy if the translator allow to just render Nurbs in modo, like npower translator for max ... that would be huge !"

 

LEARNING EVERY DAY REALLY THANKS FOR YOUR INPUT MUCH APPRECIATED...


Has anyone request any of the above features to Npower or Luxology?

NURBS support has already been requested several times to Luxology, but I don't expect to ever see it happen. Would be more likely to come from 3rd party once modo has an SDK. And in that regard, NPower can not do anything until then...

jonah

Carrarra seems to be importing 3DM and Iges file as simple nurbs---certainly from the shading point of view anyway.

If they are not being imported as nurbs in Carrara can someone explain what is happening please.

Brian

Carrara is creating meshes from those nurbs surfaces as it imports them. It may be misleading, as Carrara will leave the name as something like "NURBS object" but it's only a mesh...

And yes, I also wish that more engines could support NURBS directly. Even better if they can render NURBS directly without a render mesh. AIR (for Rhino) supports this and it's really so cool. But AIR is a RIB renderer, not sure how modo could support that feature. Unless of course Pixar wants to share that tech with Luxology... :)

jonah

NURBS support has already been requested several times to Luxology, but I don't expect to ever see it happen. Would be more likely to come from 3rd party once modo has an SDK. And in that regard, NPower can not do anything until then...

jonah


With Rhino as partner and Pixar sharing tech with Luxology we may see our dream come true...

JONAH Many thanks very valuable info above. Also Brad Peebler at the Luxology Siggraph 2008 Presentation mentioning a technology transfer wirh Pixar in regards to rendering....that may not mean (Nurbs) but the doors are open. Lets see Lets PUSH...
http://www.luxology.com/training/video.aspx?id=214