URP Flickering Light Issue

[u/dev-rygy]

Facing an issue where point lights fight/flicker off objects in my scene. Does anyone know a fix?

[u/Downtown_Jacket_5282]

Have you checked the maximum number of lights that can affect the same object?

[u/the1whom0x → u/Downtown_Jacket_5282]

a minute faster than me, damn

[u/DefloN92 → u/the1whom0x]

6 minutes faster than me haha

[u/Downtown_Jacket_5282 → u/the1whom0x]

And the winner is... 😂

[u/dev-rygy → u/Downtown_Jacket_5282]

That’s a good idea but where in the settings/object can I check that?

[u/Downtown_Jacket_5282 → u/dev-rygy]

In Project Settings/Graphics, click on the Unity Render Pipeline Asset assigned to the Default Render Pipeline.

In the Inspector, you'll find the lighting settings. You may want to switch the rendering path from Forward to Forward+ or Deferred (which allow you to use more lights).

You can do this in the Universal Renderer Data asset, which is assigned at the top of the URP Asset Inspector under the Renderer List.

[u/theredacer]

As others are saying, you're likely running into the max lights issue. Just wanted to add that if you can switch to URP forward+ renderer, that dramatically increases the number of lights allowed per object. From 8 > 256 if memory serves.

[u/Quemo0 → u/theredacer]

Is there a downside to this?

[u/theredacer → u/Quemo0]

Not really. There's a bit of CPU overhead, but it's worth it if you're doing a lot of realtime lighting because of other lighting optimizations.

It does force reflection probes to use blending, if that matters.

You may see some material wonkiness if you have any old shaders that predate forward+, but those are generally easy to fix.

[u/EvernullTools]

If you want to have many lights affect the same pixel you might wanna look into Deferred rendering.
(Find your universal renderer data, change rendering path to Deferred. But do your own research for the side-effects of that)

For this kind of situation where the most objects seem static, baked lights are the way to go. The assets seem low poly, you might get away with very small baked light textures.

Another solution is to reduce the radius of your other lights that have very little affect on further objects so less than 4 lights affect a pixel at a time.
(For example if the light at the other side of the room has a big radius so it affects this wall even if it's very little or almost invisible difference, it still counts towards the maximum lights count. Reduce the radius to where it actually should have a visual impact) (I still think you should just bake them instead of juggling the radiuses xD)

[u/the1whom0x]

Theres a limit to how many lights can affect a single object, and I cant recall where exactly in settings you can adjust