Could Cell run Nurbs in real-time?

[deepbrown]

Well basically that's the question. Could the PS3 Cell run Nurbs in real-time...that is, not converting to polygons. If this sounds absurd then say so, but there is a rumour going around...

 

[inefficient]

Even if it could, the advantages of nurbs are no longer very significant. And then there is the point that artists don't really like nurbs because they can be unwieldy and difficult to get good results from.

 

[deepbrown]

For example?

Would it bring us closer to Killzone Trailer graphics if it could?

 

[Altivec]

For example?

Would it bring us closer to Killzone Trailer graphics if it could?

Even in offline renderers, nurbs are converted to meshes before rendering. Well made polygonal models would go much further to create an efficient and expressive model.

There would be no way that this is feasible in a gaming environment in any case.

 

[pakotlar]

i hated nurbs when I was modeling. then again I was a self taugh 12 year old prof. 3d modeler (3ds Max 2 & 3). professional in a broad sense but I did do contract work. neways nurbs were a pain in my ass

 

[Altivec]

i hated nurbs when I was modeling. then again I was a self taugh 12 year old prof. 3d modeler (3ds Max 2 & 3). professional in a broad sense but I did do contract work. neways nurbs were a pain in my ass

That's an opinion. Nurbas are brilliant for what they are intended to be used for.

 

[Nesh]

Years ago I remember having a spec sheet of the PS2 mentioning the number(?) of Nerbs it could display on screen. Also some time after launch I remember reading in an interview or article about Evolution Studios' intention to use Nurbs on WRC's car models.

So I kind of have the impression that nurbs can be used real time. I dont know how extensively they can though. I ve alsways heard how hard it is to model things like that.

If i remember correctly you have to assign countless of connected dots to model something and look smooth with Nurbs?

I dont quite know since I lack the knowledge

 

[cloudscapes]

for the record I don't know a single project I've been on where our artists and character modelers used nurbs. they're an absolute pain to work with!

 

[pakotlar]

That's an opinion. Nurbas are brilliant for what they are intended to be used for.

Not really an opinion so much as an observation. Nurbs are great for a lot of types of modeling (did I say any different?), but they are a huge pain in the ass to deal with w/o converting to geometry. There are just a lot of things that you cannot manipulate on the model without converting to poly mesh. But yes, at least back then I seem to remember that there wasn't a better way to model organic shapes. Otherwise you were stuck with a primitive, the "mesh smooth" tool, and a lot of patience. Sculpting a face out of a box isn't all that much fun. Nurbs are great for stuff like that, but you will have to convert to mesh, because at least back then, the amount of operations you could perform on nurbs models were few, and it is just easier to work with a polygonal mesh for animation, etc.

The other issue is that even if the cell could handle them (and why not?), a whole new infrastructure and tools would have to be set up to import and deal with the models.

Anyways, the argument of using something like nurbs vs. tri. meshs seems very much like the quads vs tri's debate, or any other tri vs. x format debate. In the end there just aren't enough reasons to work with anything else, and the drawbacks are, at least for now, greater than the benefits.

Alas, this is all from about 9 years ago, so memory may not serve me correctly. I also was not by any means at the top of the game, so others may have a stronger vision of the benefits of one kind of setup vs another.

Edit: To answer the question posed above, yes, you could make a model from "point to point" connections (aka vertices) that look as good as nurbs models. You will never get a model that is as "smooth", but after a point it doesn't matter. I liked nurbs for quick facial scultping, simply cuz its so darn easy to get something that looks good. But the same effect could be had by extruding from a primitive, boolean ops, mesh smooth, etc.

 

[Simon F]

That's an opinion. Nurbas are brilliant for what they are intended to be used for.

Surely, though, these days one would use subdivision surfaces instead.

 

[Lazy8s]

I don't think any game on last generation consoles handled NURBS.

Some snowboarding games for Dreamcast and PS2, at least, did use bezier surfaces for the undulating terrain, though.

 

[ShootMyMonkey]

I don't know a single project I've been on where our artists and character modelers used nurbs. they're an absolute pain to work with!

Probably because rigging and animating NURBS is among the great recipes for failure known to mankind. That aside, creating a NURBS model as a starting point before converting to polymesh or creating a NURBS model as the source art for a normal map pass isn't necessarily out of the question. But in either case, it's only NURBS during construction phases, and then never again.