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Lewis
04-13-2003, 08:21 PM
Hi !

I would really like to use REAL NURBS or at least option to import IGES format to modeler wich will give me few options of desired level of freezing object to polygons if is not possible to get REAL NURBS modeling in LW :(.

Please newtek make plugin if is there no other way :(

I would even buy just separate plugin if is available anywhere :).

I use some very detaild CAD data converted from IGES to OBJ wich is very fine loaded in modeler but problems are in small cranks/gaps (in render and OGL) where points aren't welded and merged or parts have diferent level of rows/colums. So manualy finding all that is even more extensive than model whole thing in modeler from scratch :(.

In IGES all that look normal and tight but when it's converted to polys it's bad and all conection joints have small cranks where light comes trough :(.

thanks

Lewis
04-13-2003, 09:43 PM
Originally posted by CIM
Why don't you just buy Rhino for NURBS:

http://www.rhino3d.com/

Thanks for info but there is several reasons why i dont' need rhino :)

1. It's pretty pricey cosidering that's only valid for modeling (rendering sucks) - 895$ is not too cheap IMHO
2. I don't like workflow (i tryed older version demo)
3. I'am much better in LW so i would like to expand LWs possiblilityes if is possible :)
4 .....

Thaks anyway

P.S. I'am not saying by any means that RHINO is BAD 'coz it's not but i'd rather work in LW.

Elmar Moelzer
04-14-2003, 02:50 AM
Hey Lewis
The problem with Iges is AFAIK, that IGES is a modifier- stack.- based format, like the MAX- format.
This means that you need to emulate the original software (and all its tools) with the importer...
CU
Elmar

Mylenium
04-14-2003, 09:07 AM
Hi Elmar,

Sorry, but you are mistaken. IGES is not based upon a modifier stack or something similar. What is causing problems is the fact, that like in most CAD progs it uses parametric objects like solids, splines etc. So in general any program that reads IGES will take e.g. info like "make a sphere with radius 3 at x,y,z..." and create that sphere with its internal primitive library. In turn this it what would make an importer for LW almost impossible - LW doesn't support all features, their splines are not standard, no real NURBS, no fillets etc. Also since LW is based upon polys you would have to adjust polygonal approximation/ tesselation. As dissapointing as this may sound for you Lewis - RHino, Polytrans, etc. have such tools and buying one of these cannot really be avoided if you have to deal a lot with CAD (unless you happen to work with Maya also, like myself).

Mylenium

Elmar Moelzer
04-14-2003, 11:02 AM
Hey Mylenium! You are right, I was mistaken, though the parametric stuff does sound simmilar to the modifier- stuff at first.
Thanks for setting that clear!
CU
Elmar

Lightwolf
04-14-2003, 11:28 AM
Originally posted by Mylenium
As dissapointing as this may sound for you Lewis - RHino, Polytrans, etc. have such tools and buying one of these cannot really be avoided if you have to deal a lot with CAD (unless you happen to work with Maya also, like myself).
I agree with Mylenium. Also, the quality of the IGES data seems to depend on the quality of the peron that created it. I've had some really ugly IGES data that I couldn't even open properly in a program that supports NURBS natively.
Rhino has excellent Nurbs support and came out on top on my tests.
Have a look at:
http://vbulletin.newtek.com/showthread.php?s=&threadid=2300

Cheers,
Mike

Mylenium
04-14-2003, 02:43 PM
>>Also, the quality of the IGES data seems to depend on the quality of the peron that created it. I've had some really ugly IGES data that I couldn't even open properly in a program that supports NURBS natively.<<


Hi Lightwolf,

Yes, this happens quite often. Actually the blame there mostly goes to lazy CAD operators. They just don't understand that for 3D rendering/ animation you don't need references to symbol libraries, measurements, comments etc.. A clean up just cannot be avoided.

Lightwolf
04-15-2003, 03:22 AM
Hi Mylenium,

Originally posted by Mylenium
Yes, this happens quite often. Actually the blame there mostly goes to lazy CAD operators. They just don't understand that for 3D rendering/ animation you don't need references to symbol libraries, measurements, comments etc.. A clean up just cannot be avoided.
Yup, and when you work with customers who send you CAD data from their CAD department, it can be quite time consuming to talk to the CAD operator to tell them what you need (especially if you're not familiar with their software, and they aren't either :) ).
That is why I prefer a more failsave route like stl/stb, even though it involves a lot more cleanup on my side. It is a good backup modus operandi though.

Cheers,
Mike

alfabeta
04-15-2003, 10:49 AM
I'm new to LW, and I come from Rhino. This is a link to the first post I made at the lwg3d forum LINK (http://lwg3d.com:8080/forums/showthread.php?s=&threadid=11995).

I think it describes the problems with splines in LW. With all respect for LW, drawing splines in LW is like the “Stone Age” (for a Rhino user) compered to drawing splines in Rhino. If I could get Non-Uniform B-Splines in LW (LW8 ;o) (and some other really great Rhino tools) , it would make LW my love for life.

Chris

Lewis
04-15-2003, 12:48 PM
Originally posted by alfabeta
I'm new to LW, and I come from Rhino. This is a link to the first post I made at the lwg3d forum LINK (http://lwg3d.com:8080/forums/showthread.php?s=&threadid=11995).

I think it describes the problems with splines in LW. With all respect for LW, drawing splines in LW is like the “Stone Age” (for a Rhino user) compered to drawing splines in Rhino. If I could get Non-Uniform B-Splines in LW (LW8 ;o) (and some other really great Rhino tools) , it would make LW my love for life.

Chris

I saw your post on LWG and yes i hope to get some beter splines in LW so that might give us solution for importing IGES/NURBS also :).

About LW's "Stone Age" i only can say that you are right about splines but on other side of coin obviously Rhino have some stone age things so that you come to LW now (hint - rendering ;)).

SplineGod
04-15-2003, 02:09 PM
Originally posted by alfabeta
I'm new to LW, and I come from Rhino. This is a link to the first post I made at the lwg3d forum LINK (http://lwg3d.com:8080/forums/showthread.php?s=&threadid=11995).

I think it describes the problems with splines in LW. With all respect for LW, drawing splines in LW is like the “Stone Age” (for a Rhino user) compered to drawing splines in Rhino. If I could get Non-Uniform B-Splines in LW (LW8 ;o) (and some other really great Rhino tools) , it would make LW my love for life.

Chris
Lightwaves splines may seem stone age if you dont use them properly and if youre used to a NURBS based workflow. I find NURBS to be clunky and a pain to use for 90% of what most people need to do. Yes there are some things NURBS are good at.
Lightwave isnt a CAD program and was never desiged to create extremely accurate surfaces for manufacture. Nobody cares if a rendered image is 100% accurate when doing movie, tv, video game, or print work except in extremely rare cases.
Lightwave splines are in many ways much more flexible to use and FAR less constraining then NURBS. One mans problems are another mans solutions.
There are cheap 3rd party plugins to get things like fillets, chamfers and bevels like vertibevel and several products from pictrix.
Most non CAD 3D products seem to be moving away from NURBS and into SubDs. I would hate to see Newtek waste time and resources on NURBS when very few people would use it. Rhino would be the cheapest route.

Matt
04-15-2003, 02:48 PM
>Lightwaves splines may seem stone age . . .

They are!!! :)

The bezier tool isn't too bad, but when you click off it becomes frozen, if it stayed live until frozen it would be sooo much more useful.

At the moment you have to get the curves spot on, first time or your stuffed!

The spline draw tool stays live which is good but for me it's missing the handles to control tangency.

I've said this a million times, but for _me_ if the bezier tool remained live and worked like the bezier tool in Illustrator I would be a happy man! (But in 3D of course!)

I think that's a good hit between freeform control and accuracy.

But as you said "One mans problems are another mans solutions"

:)

"There are cheap 3rd party plugins to get things like fillets, chamfers and bevels like vertibevel and several products from pictrix"

Has he updated them all yet SG?

The 'three point arc' tool was a god send, but no longer works :(

alfabeta
04-15-2003, 03:50 PM
SplineGod: I should point out that I don’t mean there should be nurbs in LW, like in 3DsMax (nurbs in Max are crap, by the way) I just would like to have some of the control over the splines that I have in Rhino. Then again importing nurbs/iges would be great.

When it comes to nurbs in general, I think –for instance- making one of Lewis’ cars in Rhino would be MUCH more difficult and time consuming, than making it in LW. But for CAD work I think nurbs is great.


Matt:
The bezier tool isn't too bad, but when you click off it becomes frozen, if it stayed live until frozen it would be sooo much more useful.
I would agree to that.


I must underline that I think LW is a great tool, there should be no doubt in that ;)

SplineGod
04-15-2003, 04:14 PM
Originally posted by Matt
>Lightwaves splines may seem stone age . . .

They are!!! :)

The bezier tool isn't too bad, but when you click off it becomes frozen, if it stayed live until frozen it would be sooo much more useful.

At the moment you have to get the curves spot on, first time or your stuffed!

The spline draw tool stays live which is good but for me it's missing the handles to control tangency.

I've said this a million times, but for _me_ if the bezier tool remained live and worked like the bezier tool in Illustrator I would be a happy man! (But in 3D of course!)

I think that's a good hit between freeform control and accuracy.

But as you said "One mans problems are another mans solutions"

:)

"There are cheap 3rd party plugins to get things like fillets, chamfers and bevels like vertibevel and several products from pictrix"

Has he updated them all yet SG?

The 'three point arc' tool was a god send, but no longer works :(
Myself, I dont like beziers in 3d. 2D is fine but having to tweak handles til the cows come home is a slow tedious process. Making a point and moving it takes a lot less thought. The more you have to think the longer things take. Adding a point to a spline and then dragging it is simple and straightforward.
Lightwave splines also do not force you to create cross splines on every CV like NURBS. I can create a very simple/minimal cage and patch it. I can also control the poly count patch by patch rather then the software deciding how many polys in each patch.
Lightwaves splines have control points that are easy to adjust.
If youre used to a bezier or NURBS metaphor then you probably wont like LWs splines. If you forget all that and want to just do things quickly and use the splines as a quick poly layout tool youll be very happy. This is why SubDs exist in pretty much every 3D app because NURBS take forever to make things with. Connecting parts together is a pain.
Last I heard the Pictrix guys had or were updating their stuff.
They have a lot of very nice tools if you need precision. :)

Matt
04-15-2003, 04:49 PM
I hear what you're saying, but I like having some control, especially with tangency.

as you've said LW modeler isn't really made for industrial design type modelling, which unfortunately is what I do daily!

for character modelling I can imagine LW being great whereas SolidWorks (my main package) would be awful for that!

but from an _industrial designers_ stand point LWM is lacking.

however I'm amazed at what Lewis (and others) can produce in it!

I realise I'm comparing apples to oranges here, but this is what I use . . .

It's a quick demo of SolidWorks, bit of a download (13mb Flash Movie) but if you're interested in how other modelers differ from LW it's worth a look! (

SolidWorks Demo (webpage version, no load progress though!) (http://www.creactive-design.co.uk/temp/solidworks_demo.htm)

SolidWorks Demo (direct to the Flash file) (http://www.creactive-design.co.uk/temp/solidworks_demo.swf)