UDK: Generated/Imported vertex count ratio message

[stop619]

(reposting from game-artist)

Hey everyone,

Upon importing an .ase static mesh into UDK, I'm getting the following message:

http://img525.imageshack.us/img525/1275/udkmessage.jpg (http://img525.imageshack.us/i/udkmessage.jpg/)

Trying to troubleshoot the issue, I found this thread over at UDN: Generated/Imported vertex count ratio message - Epic Games Forums (http://forums.epicgames.com/showthread.php?t=720084)

Post #7 lists potential causes as:
1. UVs - no UV map at all, or as mentioned, no secondary UV map for lighting, or you have more than 2 UV maps
2. Smoothing - excess smoothing groups causing split vertices
3. Geometry - you have an open mesh
4. Material - there is no material

My object has UVs, and has a material applied, which leaves either Smoothing or open mesh (two intersecting elements) as the potential culprit.

I'm using 1 smoothing group as shown here:
http://img146.imageshack.us/img146/7426/smoothinggroups.jpg (http://img146.imageshack.us/i/smoothinggroups.jpg/)

In Max, this object is 180 tris, 108 verts. In UDK, the mesh has 180 tris, 222 verts. I'm pretty sure this is causing the error, I'm just not sure how to fix it :confused:

I've tested two different meshes of my own and the TV mesh from 3dmotive and only my meshes are giving the error message.

Any suggestions?

Thanks.

S6

[SanderDL]

This error message seems to show up when you haven't set up a proper 2nd UV channel for light mapping. Just make a proper unwrap for the light map and the error should be gone. The 3dmotive tutorial you mentioned is great to get you started.

[stop619]

This error message seems to show up when you haven't set up a proper 2nd UV channel for light mapping. Just make a proper unwrap for the light map and the error should be gone. The 3dmotive tutorial you mentioned is great to get you started.

Thanks, SanderDL! That did the trick.

S6

[Visceral]

Lol i have been getting this error so much it dosnt even bother me anymoore. Usually when i import stuff i use UDK's lightmap unwrap just beacuse im lazy. i mean it works in 99% of the cases.

but this thread was really informative ;)

[Zack Fowler]

It's not really an error message so much as an efficiency warning. Various things will require the engine to split up (duplicate) vertices along certain edges. Generally it's due to smoothing groups and UV seams. This warning box is basically a feature that sets a target of just 25% increase in imported versus source vertices.

You can verify this yourself, actually. Make a copy of your low-poly mesh and detach every unique smoothing group to its own element. Then select every edge that is on a UV seam (on any used UV channel) and split it. The resulting mesh should have the same number of vertices reported in MAX as it does in UE3.