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View Full Version : can i just say i'm really looking forward to when LWCAD gets NURBS surfaces?



jin choung
11-23-2008, 10:48 PM
howdy,

so as many of us know, nurbs surfaces are somewhere in the pipeline for LWCAD and i'm just gonna say that i'm looking forward to this one thing more than like anything else i can think of regarding lw right now.

i have every expectation that viktor is not gonna wrangle in LAYOUT to enable layout to take or render nurbs but that is just TOTALLY FINE with me.

if we can just have live, parametric nurbs surfaces in modeler than allow us to TRIM and BLEND (the really powerful aspects of modeling in nurbs that you simply cannot approximate with subds or non-nurbs patch modeling) and never to have to freeze in order to add details, this is going to be a HUUUUUUGE added boost to modeler's ability to work with industrial design kind-of-shapes....

doesn't have to be surface-able or anything... just nurbs surfaces and then a requirement that you need to freeze everything to polys before you can do more work on them. and as long as you have to good ability to reparameterize curves and surfaces and then control the tesselation to polys... man, we're more than good to go.

sure, i could do that with my copy of rhino3 now and i do. but having it inside lw with extremely familiar controls, working with the power of lwcad snaps (which seems very inspired by rhino btw and that's a huge benefit) and such....

sigh....

i just hope it's coming soon. it would be a dream if it arrives in 2009 sometime but that's just my wish... based on no facts whatsoever. if anyone's got some facts, feel free to toss 'em in!

jin

p.s. and sure, you can do almost everything in poly/subds that you can in nurbs. of course. but there are definitely trade-offs in terms of flexibility and freedom. although on the other side of the coin, you get added complexity. but good news is that if couched inside lwcad (which so far is handling nurbs curves beautifully), much of the complexity will be mitigated by a fairly simple, lw friendly workflow.

jin choung
11-23-2008, 11:49 PM
oh, not to mention that this would be yet one more thing that lwcad makes lw arguably more desirable over modo....

jin

biliousfrog
11-24-2008, 04:06 AM
Sounds great but, without stirring things up again, surely it would be simpler to use an application that deals with Nurbs from the outset rather than adding more bolt-ons to make Lightwave into something else? If you're really keen on modelling with nurbs why not use Rhino or MOI?

In fact MOI is cheaper than LWCAD and is a dedicated nurbs package, not a plugin that is restrcited by LW's architecture. From what I've heard MOI is supposed to be great.

jin choung
11-24-2008, 11:26 AM
yeah,

as i said, i already use rhino 3... but having it inside lw with lwcad would just make things easier. and would also make me more inclined to use nurbs. rhino's interface is just different enough (and my need for nurbs just rare enough) so that it's a jarring transition when i jump to it.

and there's not a lot to NURBS that's not "under the surface"... there's not a lot in lightwave that would "hold it back" in terms of user interface.

as with lwcad and nurbs CURVES, it's easy breezy and lwcad handles it with panache. i have every hope that nurbs surfaces will be no less capable.

especially if we're talking an implementation that is just as a "construction aid".

oh man. i am so looking forward to it!

jin

clagman
11-24-2008, 11:38 AM
jin, actually I hadn't heard of this. I've been a fan of Rhino for a long time, and I'd LOVE to have that sort of functionality available inside LW rather than deal with more importing/exporting. The current LWCAD build is fantastic but I can always use more.

jin choung
11-26-2008, 11:25 PM
ok, just came to grips with a few niggling technical details about NURBS that have bothered me until now. especially when trying to figure out what maya is doing differently from rhino. but i think i got it sorted:

http://news2.mcneel.com/scripts/dnewsweb.exe?utag=&group=rhino&xrelated=301079&cmd_related=View+thread

i post this only as an example of how nurbs can indeed be somewhat off-putting, especially if you're just in it for the art part and not for the technical precision part. manuals frequently mention some things and they do NOT tell you what to JUST IGNORE BECAUSE YOU WON'T NEED IT TO MODEL!

ACK!

anyway, everything in those posts are just an example of me being a completist and wanting to know about the stuff that is mentioned in passing in the manuals and other nurbs books and really wanting to discover for myself what i can safely IGNORE.

-----------------------------------------------------------------------------------

what i learned:

the only real thing you need to know is that a curve must have at least DEGREE + 1 control verts.

that's it!

as for KNOTS, KNOT VECTORS and SPANS, you can ignore entirely.

whew... but it took me a while to come to this realization.

hopefully, this means i won't have to go through this whole rigamarole when nurbs surfaces drops for LWCAD!

jin

jin choung
11-26-2008, 11:37 PM
oh and degree 3 curves/patches are good for most things. rarely need to go higher. degree 2 for CONICS.

jin

Chris S. (Fez)
11-27-2008, 02:43 AM
I dearly love NURBS. Being forced to freeze would sorta spoil the fun though...

When sending NURBS models to LW, I convert the cage to quad polygons (with UV's) and turn on subds.

Ztreem
11-28-2008, 11:55 AM
Sounds like fun, would be nice to have the ability to mix nurbs with sds when modeling. Rhino is fine but you have to buy T-splines to get any kind of sds modeling into rhino.

sculptactive
11-29-2008, 07:09 AM
Does anyone have a link to a tutorial that gives a step by step account of how to export a Rhino Nurbs into Lightwave?

Converting it to mesh is a must I am sure, Tools/Polymesh/FromNURBSobject, but mine are not opening in LW properly..

biliousfrog
11-29-2008, 09:26 AM
Does anyone have a link to a tutorial that gives a step by step account of how to export a Rhino Nurbs into Lightwave?

Converting it to mesh is a must I am sure, Tools/Polymesh/FromNURBSobject, but mine are not opening in LW properly..

Export the nurbs object as an OBJ, set the detail slider and import the OBJ into Lightwave. I found it more reliable than exporting to LWO.

sculptactive
11-29-2008, 10:17 AM
Export the nurbs object as an OBJ, set the detail slider and import the OBJ into Lightwave. I found it more reliable than exporting to LWO.

Thanks for the explanation. It's basically what I have been doing, but I think my problem is I have got the "wrong end of the stick".
I have had Rhino for so long I can't remember when I bought it, but never use it.
This thread inspired me to have another look at it. I noticed that Flamingo had lots of plants/Trees, which I thought would be useful for certain scenes in LW.
It is these Plants/Trees from the Flamingo library that I have been trying to convert/export.
Either there is another step I have to do or they cannot be converted to an polygon/object state.


.

sculptactive
12-01-2008, 04:52 AM
Just to confirm. The Plants/Trees in Flamingo cannot be saved and exported as OBJ. Hence why I could not work it out.