UE4 Cloud self shadowing has disappeared in version 4.12

I have lost my self shadowing. The cloud on the left I made with UE4.5 the could on the right is the same scene I recently opened into UE4.12. As you can see it has lost its self shadowing.
Is this a bug? Anyone know how I can turn self shadowing on again?

I have spent all day trying to figure this out. If someone has the time could you take a look at my Unreal particle system, I would really appreciate it. here is a link to it.
Google Drive: Sign-in

hmm the smoke material is missing :confused:

I just doubled checked the zip file. It’ is there!

There is actually a bug that is affecting translucent shadows.

It may or may not be related to your issue, but I would make sure that cast volumetric translucent shadows is turn on for the light and particle object.

1 Like