Unmapped texels (causing lightbuild to go slow)

Development Rendering
1

I like my scenes/objects to be as clean and performant as possible Still learning UE4 (who isn’t), also still learning UV unwrapping (C4D) as I never learned it properly.

I have this rainpipe modelled in C4D, I think I have a clean UV map (see screenshot) before I bring the object into UE4 , the building process takes a good while. Looking at the reasons why this is taking so long I get the results in the white box (see screenshot) … What are all those unmapped texels ?

I have to admit - I’m getting this result after I cranked the lightmap resolution on the object upto 512 (not sure why I felt the need to do this - I thought the shadows looked a little off, not sure if it’s due to the resolution of the lightmap.)

When I’m putting it back to 64, I only get .2% unmapped texels, but still , I’d love to know where those “unmapped texels” are and how I can get them down to 0% , if possible.

Any help greatly appreciated.

905c5e9d48c3bdeec7bcfdcdfac58106a10cc0e9.jpeg

2

If you haven’t changed the importer to create lightmap uv’s, it will create a new set, and make that the default lightmap layer. So your nicely laid out on may not be used.

3

Thanks for your input.
Just to make sure, what you meant to say was:
Try to uncheck the box that says “generate uv map” when importing the mesh.
Right ?

I did that and not much has changed.
rainpipe-solo_nu is the mesh that I imported with the option to create UV map UNCHECKED
rainpipe-solo_tmp is the mesh that I imported earlier with that option CHECKED, so Unreal should be creating new UV map

both rainpipes also look the same when rendered.

Screen Shot 2016-02-15 at 19.42.46.png
Screen Shot 2016-02-15 at 19.42.46.png979×30 4.93 KB

4

Probably you’ve solved this by now, but if not I’ve written about unmapped texels (and why they are so important) on my blog http://niberspace.com/blog/speed-up-ue4-lightmap-build-times/