Strange black artifacts with deferred + HDR

[JonnyOThan]

I’ve seen this reported a couple times recently. Neither person had volumetric clouds.

Player (10).log

https://youtu.be/npZXmaamHfE

steps to repro
load into the game
spawn a craft with multiple lights
teleport to a glassy area on minmus with direct sunlight
turn on the lights and then drive around until it happens really

[JonnyOThan]

https://www.reddit.com/r/KerbalSpaceProgram/comments/1nu6fum/which_mod_could_break_shadows_like_this_how_do_i/

[JonnyOThan]

Huh....so I was trying to set up a repro case, and had a probe on minmus. I was going to try to teleport to the flats but accidentally went to kerbin's ocean instead and may have done it? No eve or scatterer here - just deferred and tufx.

Disabling and then re-enabling HDR resolves it.

WAIT. simpler repro. Have a probe core sitting in the ocean, and move the camera below the waves. EDIT: well it happened once, can't get it to happen reliably. Yeah, got it a few more times, when the camera is very close to the water surface. But it only happens when the camera is pointed in certain directions. And only seems to happen when the lights are turned on.

[JonnyOThan]

And I just got an immediate repro after teleporting to the minmus flats and turning the camera. the camera definitely did not go underground that time.

I can get a renderdoc capture of this but I'm not sure if it's useful if it's not the first frame where it occurred?

Here's a save file that should reproduce it. The sun is very low on the horizon, might have something to do with it.

hdrartifact.zip

Additional data point: FAR more frequent if TAA is enabled, but it can still happen without TAA. That makes sense, because probably once it happens, TAA spreads it around.

They're definitely NaNs according to renderdoc, but it's hard to tell where they originated.

I tried to do a capture from a location that would cause the issue if TAA were on...renderdoc doesn't show any NaNs but there are negative values in the skybox. Oddly along this line....is it doing SSAO on the galaxycube maybe? Seems likely...ugh. But the bug still occurs with SSAO off.

[JonnyOThan]

I may have got a renderdoc cap for the first frame, stand by.

[JonnyOThan]

Here ya go. I've bookmarked the problematic call - it's a light!
https://drive.google.com/file/d/11-0W7B5-AjpA60veGXgw6Loc1_4-3aC4/view?usp=sharing

[LGhassen]

Could you check the new release and see if anything changes? I added in some NaN checks

[JonnyOThan]

Seems like it's fixed!

[LGhassen]

Great! Thank you very much