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csquared63
02-25-2003, 06:05 PM
Can anyone give me advice on opening OBJ files with Modeler? I am receiving these files from someone working in Maya and my ultimate goal is to optimize them for Flash.

The problem is that many of the polys have their normals flipped. Why does this happen? Is there a way to avoid it, and if not, what is the easiest way to make the model "right"? Do I really have to select them all and flip them manually?

Thanks!

Carl

csquared63
02-25-2003, 06:17 PM
I should add that I suspect these files originate from Pro-E. All of the polys seem to be triangles, and LOTS of triangles. This is why the manual flipping of normals is not realistic.

Thanks again,

Carl

bakasaru
02-25-2003, 09:30 PM
Not sure if this helps or not, but if its a Lightwave to Maya pipeline you need you might check out:


http://www.thebeaverproject.com

faulknermano
02-26-2003, 01:15 AM
Originally posted by csquared63
Can anyone give me advice on opening OBJ files with Modeler? I am receiving these files from someone working in Maya and my ultimate goal is to optimize them for Flash.

The problem is that many of the polys have their normals flipped. Why does this happen? Is there a way to avoid it, and if not, what is the easiest way to make the model "right"? Do I really have to select them all and flip them manually?

Thanks!

Carl

Align Polygons.. i think the default hotkey is Control + A. then you can press F to flip the polys if they still face the wrong way.

csquared63
02-26-2003, 04:23 AM
Thanks. I'll see if I can get my 'supplier' of Maya objects to use the plugin from the beaver project. meanwhile, my CTRL-a is going to get more use than the "f" key.

Thanks again,

Carl

csquared63
02-26-2003, 04:45 PM
Align flipped 454 polys, but didn't really affect the object—it has 28,880 polygons.

I found out today that the file originally comes from Pro-E, a CAD program, before they use it in Maya. Maya exports rtg, aliasWireExport, IGS, DXF, GE2. I know I've tried DXF before with similar results to the OBJ format.

Anyone have experience with the others?

Carl

Bonedaddio
02-28-2003, 11:24 AM
I'd may have some input for you on this, I've recently had to go through the process of getting some Pro E files into lightwave, and trying to make them look and render correctly. I'm not a guru by any stretch of the imagination, but I've had to go through this process before, and I wonder if the main problem is how modeler handles the file (!?!!??). Question: do the Maya users "see" the same problems that you do (fipped polys, duplicate polys/point issues, rendering issues etc.)?

You may have better luck if you get the Pro E files and convert them yourself using 3DWin4 or AccuTrans3D. You can get a version of ProE called "ProDesktop Express." These are available free to try or for little $, you can find them with Google.com. AT3D does give you the ability to see what you're doing better than 3DWin4, they both work.

Good luck and please let us all know how this turns out. I've burned countless un-billable hours (I'm hampered by my professional ethics when it comes to billing for what I SHOULD be able to do easily) in the Cad to LW process, and I'd love to know how to make this less painful.
:rolleyes:

csquared63
03-03-2003, 04:19 PM
I learned that the Maya files I was getting were indeed from Pro-E. I was told that they use Rhino to open and translate IGES files from Pro-E to polygons, then export from Rhino as .STL. Open the .stl files with Geomagic to reduce the polys and then save as .OBJ for Maya.

Phew! That's a lot of work. No wonder they don't appear correctly in Modeler.

He goes on to tell me that they are testing .OBJ files directly from Pro-E and that it's giving better results. He thinks the bottom-line issue is Pro-E.

I'll let you know if I hear anything else.

Carl

Bonedaddio
03-03-2003, 05:42 PM
Thanks for the update...yes, I would imagine that a LOT of weird stuff happens on the conversion route (Stereo Lithography files? *.stl? jeez) they were taking. I've seen some ugly polygonal models come out of IGES files via. the OBJ format too... is it possible that Lightwave cares more about the relationships between points and polys than other 3D programs...or does everyone else have to go through this mess too?

I have a demo of 3DS here (still considering the switch), maybe I'll try it on some of the files (ProE) that were giving me fits!

Keep me posted...

Thanks

JohnL
03-04-2003, 02:31 AM
Have a look at PolyTrans from Okino software. There is a very informative section on their website about translating ProE files to almost any other format.
If you are going to do this kind of task on a regular basis I can recommend it highly. Tech support is world-class. I don't think they ever sleep.

Check it out here. (http://www.okino.com)

Bonedaddio
03-04-2003, 06:46 AM
Thanks for the link, when I looked at what the Polytrans software does, I saw something like: "welds vertices of adjacent polygons and deletes any extra stuff" (my phrasing) which is what needs to happen for the files in question to look and work correctly in LW. This is great stuff, I'll probably try the demo. I did notice, however that I'll need at least $400 to purchase it, depending on what other modules I might need. Hmmm... I'll have to download the demo, I'm sure it's worth it (rather than staying up too late and banging my head on this issue like usual).

It's always good to hear that there are still a few companies providing tech support, too!

Thanks again.

JohnL
03-04-2003, 07:23 AM
Converting CAD files to Lightwave or any other polygon modeler, is a science. A dark science in fact. In my experience it takes a lot of trial and error. Sometimes I get so tired that when I do get things to work I forgot how I did it!!

Let me know how it works out. Rober Lansdale who owns the company is very good at helping out with specific problems. Several times the solutions to which show up in subsequent builds of the different converters.