Volumetric fog stops taking lights into account when changing scene under specific circumstances

[ArtyIF]

Godot version

v4.2.beta2.mono.official [f8818f8]

System information

Godot v4.2.beta2.mono - Fedora Linux 39 (Workstation Edition) - Wayland - Vulkan (Forward+) - integrated Intel(R) Graphics (ADL GT2) () - 12th Gen Intel(R) Core(TM) i3-1215U (8 Threads)

Issue description

When changing from a scene with a WorldEnvironment with volumetric fog enabled to a scene with the same WorldEnvironment (not sure if it should actually be the same), volumetric fog stops taking lights (at least DirectionalLight3Ds) into account. This is fixed if the first scene has a DirectionalLight3D with shadows on.

Expected:

Result:

Might be related to #83685

Steps to reproduce

1. Open the MRP
2. Run it normally
3. Hit the Load Scene button
4. See that the fog doesn't account for the directional light
5. Open scene1b.tscn and run it
6. Hit the Load Scene button
7. See that the fog works as expected

Minimal reproduction project

VolumetricFogBugMRP.zip

[interpol-kun]

I also ran into similar problem: volumetric fog doesn't take in account the lights which were disabled at the start of the scene, but were enabled later by game logic.

[Calinou]

Thanks for the report! Consolidating in #83685, as this is due to the same cause. (The issue goes away in the MRP if you resize the window or change the 3D resolution scale factor, which causes buffers to be recreated.)