Can Rhino model any object which polygonal packages like Maya are able to create?


(Alex) #41

Wikipedia and Alias Studio website both have great explanations.


#42

Optional, at someone at the exit usual realistic images.


(Alex) #43

Of course, for adding details like what you see in sculptures, you’ll definitely need to use polygons. Zbrush uses polygons to create those amazing results.


(Nathan 'jesterKing' Letwory) #44

Most render engines eat polygons before rendering anything…


(Gustavo Fontana) #45

Alex is right. If you look at the typical high-detail cars in SubDs they will always look bumpy on seams and part breaks. Like these:

Gorgeous models but if you render them in close ups you will see they are not very clean surfacing-wise.

You can however model the entire main forms in SubD/Polygons and then convert to Nurbs and then make the details with trims and booleans that do NOT mess with continuity.

This is the whole point of Mesh Fusion for Modo:

Meshfusion however is very limited since it requires all-quads and it’s also very unstable, and has an extremely confusing UI (the tool itself gets confused). But this is a good example of a tool that ‘tries’ to bring the best of both worlds.

McNeel should seriously think about bringing a non-destructive workflow for this type of iteration with mesh booleans, and curve based detailing like shutlining (but done right, since it’s also pretty terrible in its current form, looks good from very very far away, but like a dull-knife vandalism in close ups)


#46

Because they’re either hobbyists or model cars for VR, games or rendering-only (advertising, product configurators, etc.) and don’t need to put what they model into production. In automotive design, SubD is used in the early concept generation stage. But you won’t see those models “on the internet”, because automotive companies and suppliers are, understandably, highly secretive with regards to their concept models.


(Gustavo Fontana) #47

Thanks for confirming the points I raised. :rofl:


(Gustavo Fontana) #48

…you also see a lot of car models in the internet, but not coming from car manufacturers themselves, but from other companies that sell them for people to use as assets for whatever visuals they need. example:



#49

But in what then sense of NURBS? Or the grid at NURBS is better?


(Tom) #50

Do you remember about de Casteljau/de Boor algorithm from the last thread? They create you a point anywhere on a curve/surface.
Its the most basic thing but also the strongest feature of NURBS.
If you think it further, it means a NURBS model is fully mathematical represented, which opens up a lot of possibilities a Mesh representation does not have.
Now you could argue T-Splines/SubD-NURBS have the same features, just that they always guarantee you G2 which prevents the user from time-consuming surfaces-matching- operations.
But this advantage is also its biggest disadvantage, because its not always beneficial to have G2 because it limits you in precise modelling, gives you far less impact on detail and bad surface layouts.
As others already said, its very good for concept design, where form finding is much more important as other aspects.
The biggest disadvantage of NURBS is its time consuming modelling.

In conclusion, if you do some rendering for hobby, just stay with polygons. You can create much more in less time. But if you model with NURBS the biggest advantage regarding rendering is dynamic tessellation, no additional or less demanding UV-mapping, light-weight-data, better analysis, easier handling and better outcome on strongly curved details…


#51

Did you read all commenter’s comments above? It is not about “better”, it is about what the intended use case.

NURBS (or solid models) = quality surface analysis during the prototype stage, tooling, production, etc.
SubD = hobby, concept development, VR, AR, games, online display, marketing, advertising, etc.


#52

I understand, but the question was inaccurate…
Cars are better displayed on the image (especially close plans) at NURBS. But the grid of SubD looks better in comparison with NURBS. What can be told here?
There is a simple part:


2018-04-10_174241


(Alex) #53

You need to import STEP format into your rendering software.
For instance. 3ds max can handle STEP nurbs surfaces easily so Vray or Corona can render it.


#54

So not always - where NURBS is very simple in use. Somebody can confirm my words?


(Alex) #55


This image was modeled by me about a year ago in Rhino. I rendered it using 3DS MAX and Vray without converting it to a mesh.


(David Cockey) #56

In what way does one “grid” look better than the other? Why is that important?


#57

Here the grid is better:

Unless it doesn’t influence quality?

@Alex_Wright, Cool :grinning:


(Nathan 'jesterKing' Letwory) #58

The conversion is typically done automatically for you - just as in Rhino when switching to Shaded, Rendered, Raytraced or similar mode.


#59

Precisely! On this subject there is an ExtractRenderMesh team which pulls out a grid.


(Gustavo Fontana) #60

Nathan, Rhino meshes Nurbs for rendering using a pre-determined mesh setting. You could be in a situation where you have a very light topology part or a small detail and you do a close up in your viewport navigationor a close up rendering and you see mesh faceting. Some programs have adaptive mesh seti gs for Nurbs (and SubDs) so no matter how close you get to something you will never see a facet because the calculations are done on the fly pre-render to always keep subdividing based on pixel scale so no facets are visible. I’ve only seen this for off-like rendering not for real-time. Since the re-meshing takes time. Not as long as Rhino meshing time, but still takes time.