SpotLight3D causes clustering artifacts with large light angle and small camera far plane

[Fabien2S]

Godot version

v4.1.1.stable.mono.official [bd6af8e]

System information

Godot v4.1.1.stable.mono - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 6GB (NVIDIA; 31.0.15.3713) - 12th Gen Intel(R) Core(TM) i5-12600KF (16 Threads)

Issue description

• This issue persist in 4.2dev4
• Does not require a WorldEnvironment node
• Probably not related to SpotLight3D turns negative, and creates black boxes on small angles with volumetric fog #78500, as this issue occurs without volumetric fog

With a Camera3D far plane of 4000 (default value)

With a Camera3D far plane of 100

Steps to reproduce

• Camera3D must be "behind" the SpotLight3D
• Camera3D far plane must be small (tested with 100m)
• SpotLight3D angle must be large (tested with 75°)

Minimal reproduction project

MRP.zip

[Roboticy3]

I have a similar problem on my project! there's a situation where the clipping plane needs to be close and it causes the same artifacts. I hope I can find the time to add a demo project later, but I'm using directional lights and getting the same issue.

I experimented with changing the sky and environment parameters, because I thought that would be the issue, but apparently not.

Graphics code in general is definitely spooky and or haunted. No shade to Godot, I use Blender too and thats just how it is sometimes. Keeping the far plane above 100 is my best fix so far.

System Information

Godot v4.1.1 stable. Linux Mint Vera, AMD Ryzen 3 (Picasso) dual-core, integrated graphics.

[Roboticy3]

Ok, here's a demo project. It looks like the lighting bug happens on geometry within a certain range between the camera and the far plane.

WASD to move the camera, up/down arrows to move the far plane further/closer, current far plane prints to debug. Hold left click to rotate the cube.

It's probably a lighting optimization that breaks under these conditions, and you can achieve the same bug with any light source.

I'd like to not have to worry about this too.

godot81772.zip

The only time I was truly free from this on my end was at around 300.

[jcostello]

I experienced the same problem in the TPSDemo