UDK Smoothing Issues

James Ordner

I modeled an M1 Thompson in Blender, UV unwrapped it, and exported it as an OBJ for baking the normalmap in xNormal. Everything looks fine in Blender:



However, after exporting to FBX and importing to UDK, I get artifacts like these all over the model:



Any idea what's going on? I'm using different smoothing groups, so it's not an issue of all the normals being averaged. Here's an unlit view of the model in Blender to show the different smoothing groups:

James Ordner

After experimenting further, I found that importing the model to UDK as a static mesh fixed all the problems. It's not a permanent fix, as I need it a skeletal mesh, but it may help to figure out the problem. Any ideas?

EarthQuake

Your images are not showing up so its hard to give any advice.

The current build of UDK which supports implicit normals importing(for improved normal maps) only works with static meshes as you have found. Try Alec Moody's Handplane here: http://www.polycount.com/forum/showthread.php?t=108744 it should work with rigged meshes as well as static in UDK.

James Ordner

I gave Handplane a try, and it's a great tool! I'll definitely be using it in the future. However, my topology is not good for making the entire model a single smoothing group. In flat areas, the topology is... horrible. I did not worry about it because, it being flat and having its own smoothing group, you would never be able to tell. So unfortunately, without retopoing the entire mesh, Handplane doesn't solve my issue because it requires the entire model to have only one smoothing group.

Scruples

I thought handplane reads smoothing groups, just not vertex normals?

James Ordner

As far as I know, Handplane averages all normals, reguardless of smoothing groups.

EarthQuake

James Ordner wrote: »

As far as I know, Handplane averages all normals, reguardless of smoothing groups.

That certainly should not be the case, if you're having issues with it you should post in the thread.

James Ordner

EarthQuake wrote: »

That certainly should not be the case, if you're having issues with it you should post in the thread.

Thanks. I have a feeling it has to do with Blender's way of implementing smoothing groups (physically splitting edges rather than using smoothing groups). I'll post about it on the Handplane thread.

EarthQuake

Oh yeah that makes sense, make sure to mention that when you post as I'm not sure how the tool will treat that, and I'm sure it will be good info for Alec to know.