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philipbryan
02-27-2004, 12:27 PM
I want to use Lightwave to render some NURBS surface models I made in Alias Studio. What is the best way to tranfer the files?

does Lightwave support NURBS?

mattclary
02-27-2004, 12:54 PM
I don't know d*ck about Alias, but I can pretty much guarantee you you are going to have to export the files to another format, such as 3DS or DXF.

Mylenium
02-27-2004, 02:12 PM
LW does not support NURBS, but Maya does (a little sideway advertising here).

Well, you would need to convert them into polymeshes in Studio and then export them as OBJ, DXF or STL. Those file types can be loaded back into LW and then treated further. Depending on the complexity of your stuff, this process can take a while and be rather painful (expext some screwed up parts in your meshes). You'd be much better off if you stayed in Studio and did all the rendering there.

Mylenium

KeithJ
02-29-2004, 06:32 PM
Just wondered.. will we be getting nurbs in LW8?

I've never used them but a lot seem to rave over them!


Keith

Mattoo
03-01-2004, 02:49 PM
No one but an idiot would rave about NURBS. You're not missing anything.

Appart from a few particular idiosyncracies about them that more technical people can exploit there really is no need for NURBS now-a-days.

mattclary
03-01-2004, 03:17 PM
Originally posted by KeithJ
Just wondered.. will we be getting nurbs in LW8?

No way in hell. LightWave just doesn't work that way, it's a very fundamental difference.

KeithJ
03-01-2004, 05:14 PM
I thought not.

What exactly are nurbs??.. don't answer that! I'll read a few mags and find out for myself.

Ta

Keith :)

mattclary
03-01-2004, 05:39 PM
Non-uniform rational b-splines

Chazz
03-02-2004, 09:35 AM
Originally posted by Mattoo
No one but an idiot would rave about NURBS. You're not missing anything.

Appart from a few particular idiosyncracies about them that more technical people can exploit there really is no need for NURBS now-a-days.

That's just a silly remark.

AngelDream
03-02-2004, 11:57 AM
One of the first modelling paradigms was polygons, of course, as you all know, you can not represent even one real object with polygons, 'cause everything has curves and smooth surfaces. Then, man said "Let there be NURBS" and the NURBS were created, providing much more control on modelling, some of their problems about them is their weird topology and you the fact that you don't have the control right at the tip of your fingers, like polygons.
Subdivision surfaces, the modelling system used by LW, has the advantage of both, polygons and NURBS, you have extreme control on surfaces as well as soft, rounded surfaces for organic modelling. Of course, Subd's are a bit more complicated than NURBS.
If you think that NURBS sux, you should ask yourself why Maya still has NURBS, if it has Subdivision surfaces too. I must say that to me, Subd's are great and I love the modelling system of Lightwave.

Mylenium
03-02-2004, 11:42 PM
Well, why I don't think NURBS really suck, but many of their paradigms and quirks still escape me after all these years (ever since back then when I used Power Animator 8). They are just awkward to use in the context of animation. Especially since most renderers convert them into triangles anyways. They should have stayed in CAD-land in the first place and that's where they really can show their advantages such as infinite resolution, curvature control etc.. I wouldn't expect anyone in the 3D animation world to put too much effort into implementing them into new programs. Maya and the other high end tools will always have them and they will make viz people happy but I guess most other 3D people don't give a damn about it.

Mylenium

Mattoo
03-03-2004, 03:50 PM
There's quite a few reasons why programs such as Maya and XSI still have NURBS support and that's because there's still a lot of people out there that use them. (interestingly, a lot of people are idiots also).

There's a lot of larger, older companies still using them out of legacy than as anything else. As time goes on those companies are catching up.

Another reason is that the NURBS tools in these programs, such as Maya, are much more robust than the relatively new SubD tools. Maya's implementation, although very impressive, is also quite underdeveloped in the userbility, stability and speed departments.

Lightwolf
03-04-2004, 03:24 AM
Originally posted by Mylenium
Maya and the other high end tools will always have them and they will make viz people happy but I guess most other 3D people don't give a damn about it.

Well, as long as you have to pay the bills, and do Viz work every now and then, NURBS are a great feature to have. Heck, I'd even be grateful for decent, "live", spline patches in LW.
Just look at all those SubD car models people create in LW. Sure, they look great, but think of all the time you could save if you had NURBS...
Not everyon uses LW for character animation, actually I think that only a minority of users spend all of their time creating organic models....

Cheers,
Mike

Lynx3d
03-04-2004, 08:15 AM
Oh yea i'm definitely with Lightwolf...you can model darn clean models with NURBS, you can have perfect bevels 'n stuff where you just get crazy subd'ing your mesh to death.
If you ever worked with e.g. Rhino on some more technical meshes you can't really believe that NURBS suck...

tburbage
03-04-2004, 02:13 PM
Well, getting back to the original post, I've had pretty good luck using .obj format to get data from a NURBS modeler into LW. Don't be surprised if you need to do a fair amount of cleanup in LW though.

jaxtone
03-05-2004, 07:21 AM
They should have stayed in CAD-land in the first place and that's where they really can show their advantages such as infinite resolution, curvature control etc.. I wouldn't expect anyone in the 3D animation world to put too much effort into implementing them into new programs. Maya and the other high end tools will always have them and they will make viz people happy but I guess most other 3D people don't give a damn about it.

Well! I wonder who these "most other 3D peoples" are? Mylenium you make me feel stupid when I place food on the table for my family. Do you tell I am a jerk when I accept to work for the production industry with CAD models?

Since I earlier among other professions also have been a consultant CAD designer for truck engines I would like to say, "yes it can be really jerky" to make a crankshaft for a heavy truck and spend months with B-splines C-splines and so on, Months of calculations for FEM and measuring. But in the other hand I havent got any rich parents or millions on the bank so this is the way for me to get a fat paycheck so I can create more fun stuff like music videos and abstract animations to.

And in these fancy moments I wish there were smarter ways in Lightwave to implement different industrial formats as well. Who knows, in that case maybe next music video I produce will contain both a flying crankshaft and one of these more common space ships we have seen so many of in the 3D world.

Cause you know what? I wouldnt even think of building a model that would work in reality in Lightwave, cause there are no way to export it and theres no way to make it functional.

I enjoy Lightwave very much but not all parts of it, it would only disable my possibilities to earn a few bucks as an animator among different customers.

J

iaef
03-08-2004, 01:56 AM
Well, about transferring Maya NURBS into LW, there seems to be some other ways which you could implement into your production process.
Okino Graphics offers a suite to make conversions between several programs of your models. What gets a highlight on this, is that you can transfer your textures and even your animations from one program to another. This looks to me like a fine solution, altough an expensive one.
There is also the Kaydara FBX plugins, but I dunno if it supports NURBS translation into LW. Well, just looked into their site and, nope.
I use Rhino to read some Maya models and then try to refine them in there while exporting to LW format. Just to have a little more control in translation.

About the NURBS theme.. what I heard is that every movie that is made will be modelled into NURBS, simply because the huge size of the screen would show any polygon edge that doesn't looks organic. The way NURBS are converted into polygons on a renderer like renderman, seems to put more polygon detail where it is needed (edges).
Of course it is more controlled to work on polygon mode, and I prefer it myself. But if you are going out into large format, it seems to be better to have the renderer transform the NURBS ito optimized meshes each and every frame. But this will also take more processing time and power.
The way we could see this maybe implemented could be to have a NURBS simulation with splines (just a crazy thought) :D and to make the hypernurbs refine the model edges with more polygons, so any close up won't show sharp edges... :)

jaxtone
03-08-2004, 02:29 AM
I like it and think your crossover idea is splendid... actually I always prefere wild ideas rather than pressing the safe button...

Go ahead... give us some more of these teasers.

J

wizlon
03-08-2004, 03:01 AM
What does the b in nurbs stand for bi-linear or bi-cubic? or none of the above?

Lynx3d
03-09-2004, 05:56 PM
"bspline" stands for "basis spline" (i think)
there are several spline interpolation techniques...bezier, akima, b-spline...
b-spline have the advantage that you can create perfect circles with them and the influence of one vertex is local and not global like on bezier splines (however bezier splines in graphic software often are attached cubic bezier splines with fixed tangents to avoid global influence and have a spline that goes through every 3rd control point while the two inbetween are "handles")

jaxtone
03-09-2004, 11:03 PM
Hi guys!

About the definition of NURBS "Non-Uniform Rational B-Splines" I think the B stands for "Bicubic", but hell I am not really sure because it was ages ago I messed with the language of maths...

I think we need some help here :)

But check this out, if you wanna fall asleep... its technical... its booring, but most of all, its crispy clear facts...

Juris

http://mathworld.wolfram.com/B-Spline.html

jamesl
03-10-2004, 10:49 AM
Sub-d's are quickly gaining acceptance (even for large format) in the production world, for the obvious reason that their easier to model with and use generally less overhead. However, many studios have legacy tools that manipulate, translate, mutilate geometry in ways that are essential to their pipeline, and those tools are 10+ years old and are expecting nurbs surfaces. I know of one studio that has converters that faithfully switch models from nurbs to sub-d/poly and back. Renderman has no problem tesselating sub-d's to the micropolygon level.

My opinion is that unless you're building something that needs to be manufactured to EXACTING tolerances (not a market LW has pursued), or you yourself have 10 year old legacy tools that you just can't part with, nurbs are unnecessary.

j

lesterfoster
12-27-2004, 01:46 PM
I just wanted to pass this link on. It is a interactive website. You can interact with some of the photos.

An Interactive Introduction to Splines (http://www.ddt.pwp.blueyonder.co.uk/evgeny/Intro/Intro.htm)

nimoscar
01-20-2005, 06:54 PM
okay okay, just seen the thread, and , anyway, i'm totally brand new to this forum ... but I'd really be glad if the lightw will implement with real nurbs....
what about modeling something really elegant and clean just having a side and top pic of an object to begin the drawing?that would make a big difference.
and... sorry for my english... :(
niko