I’m having an issue in the 4.12.3 editor (launcher version) on Windows 7 where the editor hangs when the camera enters a post processing volume that overlaps another where both have differing ambient cubemaps set and each have their cubemap intensity fields checked. It doesn’t seem to make a difference what the intensity values are set to or which cubemaps are used as long as the cubemaps differ from each other.
To reproduce it, I created a new map from the “Default” template. Then I created an unbounded post process volume with the stock “DaylightAmbientCubemap” set as the ambient cubemap and intensity checked (left at the default value of 1.0). I then created another post process volume with a higher priority, set the ambient cubemap to “SunsetAmbientCubemap” and checked intensity. Then when I moved the view inside the second volume, the editor froze. After it freezes, in Task Manager, I can see the editor process using a solid 25% CPU (I have a 4-core CPU). It doesn’t crash gracefully with a bug report window. It seems to remain hung forever. I have to kill it with “End Task”.