Question Why does my lightmap have odd shadows?

I'm using HDRP, baked with these settings:



There's 1 sun light in the scene:



This room is not getting any direct light, basically all indirect light. I've tried increasing the samples count and lightmap resolution but it doesn't really help much

 

Try raising the sample values (mainly indirect) and see if it improves.

 

Yep tried setting it to 1024, it changes the pattern of the shadows but it's still looking bad

 

You must use very high indirect samples like 2000 up to 10000

Also you can use fake indirect light solution to reduce noise:

 

I cranked Indirect samples to 7000 and some of the other numbers up as well, it looks... better... but it's still not perfect. I guess I'll look into that fake indirect light solution

 

Reduce lightmap resolution a bit ( I think 64 is too much, maybe 30-20? although I don't know how big your scene is ) and then add another 0 at the end of all Sample values.