Lightmapped objects no longer have ambient light colour applied

Unity Engine
1

Hi there,

I’m trying to bake my scene for performance reasons. I have some strange requirements due to the pixel art style of my game, namely that I turn the indirect multiplier down to zero and turn off bounces. This results in very dark lightmaps with no environment lighting (I just use a solid colour) being applied to baked objects.

I have been able to find people having similar issues but no explanation as to why or how to fix it. It seems like environment light should be direct so not rely on bounces or indirect multiplier or anything.

My current fix is to have a baked directional light in the scene that copies the ambient colour. I turn this on before a bake and then turn it off afterwards. (another issue is that I have to boost this directional lights intensity to 1.4 in order to match the ambient colour).
It would be great if I didnt have to do this, or if I at least understood why the ambient colour is no longer applied to baked objects (i think the understanding would be more beneficial).

Any help on this is much appreciated. Thanks!

Attached are screenshots of my light settings along with an example of the unbaked scene, the baked scene with no ambient colour being applied and with my direction light.

  1. Everything is lit realtime and ambient colour is applied.
    5033888--493514--01_everything_realtime.png

  2. Baked lighting is applied to lightmap static objects. Realtime lights still affect non baked surfaces. Baked surfaces are no longer affected by the ambient colour.
    5033888--493517--02_baked_no_ambient_colour.png

  3. Baked lighting is applied to lightmap static objects. Ambient colour is baked in to lightmap static objects using a directional light. Realtime lights still affect non baked surfaces.
    5033888--493520--03_baked_fake_ambient_colour.png

  4. My settings.

    5033888--493523--04_settings.png
    5033888--493523--04_settings.png444×1075 55.9 KB

2

Environment lighting is currently folded into indirect lighting, so multiplying that with 0 (or selecting 0 bounces) will kill environment lighting. This has historical reasons, as environment lighting used to be a byproduct of the GI pass (as in if we didn’t hit anything with the GI ray, we must’ve hit the environment). We introduced an explicit direct environment lighting pass a while ago (that’s what the Environment Samples value actually controls), but are still folding it into the indirect lighting to be consistent with previous behavior.

1 Like