View Full Version : How to make car modelling easier

10 October 2011, 05:40 AM
Hi all,

I'm fairly new to modelling. Started 2 years ago but never went crazy with it aside from school.

I'm currently trying to model the Audi R8 using another method of curves, lofting, boundary, etc. Trying to do it via nurbs this time instead of polygons like I did on the Mitsubishi Lancer Evo X I did 2 years ago. I'm having the hardest trouble with this because I want it all, preferably, in as little pieces as possible and it is near impossible for me to get it looking right. I have troubles getting it to look like the actual thing. Especially the car door!! I'm unsure how to open up that kind of detail. Here is what I have so far...

10 October 2011, 12:32 PM
To model a car in NURBs, you basically have to patch together a network of nurbs surfaces. Most start by making the general shape like you have already done, then start to make separate panels and details by using the base shape as a guide to generate other surfaces off of. So to make the door, you could project two vertical curves that cut into the panel like they should, then duplicate the top and bottom horizontal edge curves from that side panel shape you made to make your door with. You could then make a boundary surface from those curves or use a bi-rail operation, which may work better. Kinda hard to explain without drawing it, but I hope you get the general idea.

10 October 2011, 02:55 PM
oooo I see now. So it doesn't have to be perfect from the get go huh? Well that's a relief. I've been thinking about this all night while but yes what you said makes some sense. Just takes a bit to get used to the terminology as well as how you explained it. I don't entirely understand what you said about the door part. The part that was confusing was when you said to duplicate the "top and bottom horizontal edge curves from that side panel shape you made".

And guess I should research bi-rail. Though what is the difference/advantages of that over boundary surface if you don't mind explaining in laymen terms?

Thanks so far!

10 October 2011, 05:35 PM
Theres plenty of ways to go about it really. It really depends on the shape of the car. Although Maya has some decent NURBs features, its not as comprehensive as its distant cousin StudioTools. Not that you need to make class A surfaces if you are just making this for renders, but it is interesting to see how it is done in the automotive industry. There are some great videos here from Technicon showing how class A surfaces are achieved in automotive design:

Here is a video from there showing all the patches that make up their example model:

He mentions primary, secondary, and tertiary surfaces in that video. The surfaces you have now are basically primary surfaces. The secondary and tertiary surfaces are the ones you generate off of these such as blend surfaces. The videos are using StudioTools, but many of the techniques can be done in Maya as well.

Bi-rails are useful when you have a shape that sweeps along like the side of a car. The manual has a decent explaination. You would probably use a "birail-2" to make the door. This uses 2 rail curves (hence bi-rail name), and 2 profile curves (hence -2 on the end). Square/boundary surfaces don't have the same control that bi-rails do.

It's been a while since I made a NURBs car model, so I don't have any better links for tutorials, but a good place to check is

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