View Full Version : OBJ export issue - mesh distortion.

01-01-2010, 07:20 AM

Happy new year and all that :)

I'm having some issues getting obj and lwo files exported from LW to open again, even in lightwave.

I am creating the objects in Lightwave 9.6 and exporting them as .obj files, these files open successfully in poser and in hexagon


However when I re-open the object in lightwave I get the following.


and in Vue


Ive tried to work around this by exporting it from hexagon as an OBJ but when I try and open them in vue I get the following error message.


In Lightwave the deformations are gone and the model is ok.

I have tried this on my desktop computer and my laptop with the same results both time (trying to see if it was a driver issue/bad install etc etc)

I also have tried this with a LWO file directly from lightwave, the results where different as in it loads into vue, but the uv file is completely wrecked/not read properly. Initially I thought this was due to it being tripled when it was brought into vue, so I tripled my model in Lightwave and redid the uv maps/colour maps etc but the issue still remains, the image in the link below shows the difference between the two models.


Here is the mesh and a reduced size uv map.



Anyone have any ideas whats going wrong?

Thanks for your help :)

01-01-2010, 08:12 AM
Try selecting the front wall of the house, cut it and paste it back in..without merging points.....see if that helps.


01-01-2010, 08:28 AM
you absolute legend...

Thank you so much :) i've spent like a full day messing about with this hah

01-01-2010, 09:29 AM
Whats your smoothing level looks like it might be to high, also try merging polys as well

01-01-2010, 12:49 PM
haha....it's something I remembered about Poser 4.

To get a straight edge on corners, you had to cut and paste the polygons before exporting them as obj's...otherwise, it would look awful in Poser.

Glad it worked :D


01-01-2010, 12:52 PM
curiously it was only poser and hex it worked in!! 3D programs are wierd :P

John - ideally there didnt want to be any smoothing on, so thats probably another issue, thanks for the tip, i'll have two places to look next time :)

01-01-2010, 01:36 PM
Try using DAZ studio, its free and can import cr2, pp2 and obj files and probably does a better export for LW than Poser, i only use poser for characters with bones.

03-29-2010, 08:27 AM
I have run into this same issue with the export, but it has nothing to do with UV mesh distortion. My geometry is more of a tube so it requires a level of smoothing, but at much lower settings -- around 36 or 42, to create hard creases where i need them. When i export from LW with the correct settings and import into the software I am using it for, the mesh looks horrible. After re-opening the obj file in LW, i see that all textures have "smoothing" after the original surface name and it is calling upon a normal map for smoothing. What gives???

Are there some sort of settings to tweak for this exporter? What is the easiest way to get the smoothing that i want exported??

--First image is original lwo with setting i would like -- Second, re-imported obj--

03-29-2010, 02:56 PM
Looks like the same issue to me...have you tired my first suggestion, cutting and pasting the polygons you want to have an hard edge to?

For example in the image, the areas coloured red and yellow would be selected and then cut as one object and then pasted back.


03-29-2010, 03:22 PM
Ha, yes that is the process that I am going through right now.
I think this is going to work for me -- just a huge pain.
Thanks for the response!

03-29-2010, 03:26 PM
Go to the Surface Editor, and see if there's anything in "vertex normal map" (bottom of basic tab). Unselect the map if there is one and see if it's at taste.

03-29-2010, 03:36 PM
Ha, yes that is the process that I am going through right now.
I think this is going to work for me -- just a huge pain.
Thanks for the response!

It would have been easier if each of those had a different surface name, instead of having to do it manually.
Unfortunately, I don't think there is a plugin that would automate the process...would have been cool.

Best of luck!


04-01-2011, 10:43 AM
I'm having a similar issue with a new project I'm working on. I made a huge model of a factory with hundreds of little, low-poly machines, people, shelves, boxes, etc. I need to export this for another company because it's being rendered as a 3D glass holographic print (see http://www.youtube.com/watch?v=jx3TSQul94E if you're curious about the end-product, it's pretty cool actually).

They need the model in OBJ format. So I exported it with "Export Normals" set to on (NOTE: had to export in LW9.6 because LW10's OBJ export is broke and trashes the UV map :devil:).

I get the same as above, any surface that has its smoothing angle set above 0 gets "_Smoothing" appended to it and uses a Vertex Normal Map. My problem is, both when I import the OBJ into Layout and on the other company's end, the smoothing is way off and everything looks OVERSMOOTHED. Most of my surfaces were at like subtle smoothing angles of 19 degrees or 39 degrees originally, but when I re-import the OBJ any surface with smoothing looks like it's set at like 100 degrees and looks blobby and crappy.

The model is far too detailed and huge to do all the polygon "cut and paste" tricks above... is there any other solution to this problem now? It's like the vertex normal map the OBJ exporter creates has the wrong values in it.

As of right now I've been forced to send the company a version with smoothing off on the entire model, which is really, really irritating after all the time I spent on the model. :devil:

04-01-2011, 06:29 PM
Ha, yes that is the process that I am going through right now.
I think this is going to work for me -- just a huge pain.
Thanks for the response!

Pain? Just use Unweld..