Lightmass Errors

Hello All,

At the moment my lightmass is acting strange, i wonder if anyone may be able to help me out. I have around 20 objects in my scene, including walls and everything, each is set to 1024x1024 for lightmass rendering. At the moment, if i hit production render or preview render, the lightmass is happy to start, then hangs on 0% for a bit before killing the process. As far as i can tell, i don’t get any errors in the message log, it looks like it just stops, and i’ve rendered far bigger scenes with far more objects before on the same computer. I have 64gb ram, and im using windows 10 if it helps, but at the moment it seems like it may be a memory limit issue?

I should also add the process SOMETIMES works, but it seems very unpredictable as to when. I’d say it fails around 70% of the time at the moment.

Id appreciate any help

Hi Dark_Jubei,

Check out the following link:

[Why is my light build stuck at X%, or Why does building lighting take so long?][1]

To show the Swarm Agent while building lighting in UE4, click the Swarm icon in the lower right of your Task bar in Windows:

101482-swarmagenticon.png

Make sure you are using a Lightmass Importance Volume to make sure you are not rendering unneeded space.

A Couple of other steps to try:

  1. Delete the Config, Intermediate and Saved files in case a file has become corrupt

  2. Try steps listed in the Link above

  3. Test Build Lighting in a Blank Third Person Project to see if lighting is stuck there.

  4. (Last Resort) Migrate your assets of your current projects to a blank project where light is working

-Let me know if none these steps help,

.

I’m marking this as accepted for tracking purposes. If you are still experiencing Lightmass Errors, please respond with what steps you’ve tried from those listed above. -Thanks.