Weird shadow discoloration using GPU

Hi all!

Please bear with me, brand new to Unity. Been using Unreal for a long time, and I'm getting hang of Unity and really enjoying it, however I've ran into an issue that I cannot seem to solve.

Trying to bake a small airplane cabin slice using GPU Lightmapper. First note: CPU lightmapper works perfectly fine, no errors, no issue, but slow as hell running on an i9-9900K. The GPU lightmapper is quick as hell on the RTX 2070 Super.

So the issue is: I have a model, a piece of this cabin, that has a window hole on it. I have 4 of these placed in the scene. They are static, contribute to GI. The scene is lit by a single Directional Light that's set to Baked only. The rest of the scene is capped with default Unity Cubes.

Using the HDRP sample, and Lightmap Settings are the Ultra version from the project.

After baking, there are weird discolorations on these cabin slices, that do not appear on any of the Unity cubes. Also as stated using the CPU lightmapper solves this issue completely, but I would like to keep using the GPU one due to speed.

Changing any settings, or resolution etc does not solve the issue. There are no UV overlaps, or any other errors.

GPU Bake:




CPU Bake:



Using Unity 2021.

Anyone knows how to fix this?

 

Which version specifically? It looks like a bug I reported many months ago that so far has only been fixed in the alpha for 2021.2

 

I believe it's the same issue as this :
https://forum.unity.com/threads/progressive-gpu-lightmapper-preview.561103/page-14#post-6784154

https://issuetracker.unity3d.com/is...plit-when-progressive-gpu-lightmapper-is-used

 

Hi! Thank you for your time. I’ll get to the office soon, and report back the actual Unity Version.

 

So the actual version is 2021.1.9f1

 

UPDATE: It seems to be the same issue that you have reported. Grabbed the model, popped it into Unity Alpha, baked with Progressive GPU, and no weird splashes on the lightmap.

 

It seems the fix still hasn't been backported anywhere and is still only available in the alpha, which is a bit frustrating since I reported the bug 6 months ago and it still hasn't been fixed in a version I can use. :/