NURBS crinkled bangle bracelet

[jbshorty]

Hi. This is a model i am developing in Rhino 4.0 beta, it's my own design for my daytime job. The model is a NURBS solid. The render mesh is approx 480,000 polygons. I might break it into sections to be manufactured, or maybe i will push the face deeper into the body so we can inlay a material into the base frame. So my modeling work is quite far from being finished ... I will try to post some renders of material concepts when i have a chance. In the meantime, i welcome all of your comments and/or criticisms ...

[mon_stdnt]

No critics here ,but the comments is WOW. Love the detail modelling.

[jbshorty]

thank you, my only friend in this thread

[Piem]

No..I'm one of them too.
This bracelet is really cool !!
i

Yes, the model is very nice. But I am perplex about this question
Do you manage to render the mesh and if yes, in which engine?
Second question, are you satisfied about export ?

When objects are rendered in nurbs...all is fine, but the real result (stl or other) can be different .
Have you some other shots of the file as polygonal ?.. if you break the breps as they are, I guess you can have an headache to keep "unified" groups..in fact..nearly impossible to get the perfect result. (?)

[kantié]

Beautiful model !

[jbshorty]

Thanks for the positive comments ! These images are not renders, just a screen capture from Rhino. But its impossible to shade a nurbs object, so what you are seeing on the screen is actually the polygonal mesh combined with the Nurbs isoparms. Here is a screenshot of the polygonal mesh wireframe... It's normally true that if i mesh two seperate nurbs objects, then the mesh parts will not match because the program doesn't know they are supposed to match. For this model, it is already a solid nurbs object with a render mesh. So I first extract the large exterior face, and then both Nurbs objects retain the render mesh toplogy the same as if they were joined. Then i use Rhino's "extract render mesh" function on the 2 Nurbs objects. The result is 2 perfectly matching mesh objects. I joined them together to test the result, and they were listed as one solid mesh object. The real beauty is the exterior face has perfect UV's so i don't have to create them myself ...

I plan to render in Carrara, but i find Carrara's 3dm import is very crappy when compared to Rhino's export. So i convert all objects to mesh within Rhino, and then export as obj. So far i have been very pleased with the results of this workflow, and Carrara can render these heavy meshes surprisingly well. But i have to use wireframe preview in Carrara to keep a fast redraw speed. I will post some render tests when i have a chance...

[Piem]

The tesselation looks efficient

[jbshorty]

That's a great characteristic of nurbs, no extra meshing where you don't need it. Take a look at my previous WIP thread. that's a much better example of mesh efficiency.

http://forums.polyloop.net/showthread.php?t=9023

[jbshorty]

Piem, until a few months ago i'd always rendered with Rhino's native Flamingo render engine. Now i am first learning C5Pro and experimenting with various export methods which are good for rendering. This morning, i realized i can explode the extracted mesh from a nurbs polysurface. And the exploded mesh will have perfect mesh edges along the original edges of the nurbs surfaces. there is no gap between the mesh parts. and all the individual meshes have the UVs of the original nurbs surfaces . So back to your original question i think it's not necessary to break the object before meshing, as it's so easy to break perfectly after meshing...

[Arsenic]

Originally Posted by jbshorty

Piem, until a few months ago i'd always rendered with Rhino's native Flamingo render engine. Now i am first learning C5Pro and experimenting with various export methods which are good for rendering. This morning, i realized i can explode the extracted mesh from a nurbs polysurface. And the exploded mesh will have perfect mesh edges along the original edges of the nurbs surfaces. there is no gap between the mesh parts. and all the individual meshes have the UVs of the original nurbs surfaces . So back to your original question i think it's not necessary to break the object before meshing, as it's so easy to break perfectly after meshing...

I'm curious about how you do that... ^^ I was a rhino addict in the past and now, I'm a member of the polygon church.

[jbshorty]

Originally Posted by Arsenic

I'm curious about how you do that...

how i do what the meshing or the modeling?