directional light shadows not working in large world

[PtrMan]

Godot version

v4.1.1.stable.custom_build [bd6af8e] (double)

System information

Windows 11

Issue description

The object is at position <75000, 0, -149900> where lighting fails (the shading is completely black), while other nodes also exist at far away distances. The shadows work when the object is close to the origin (~2000 meters).

Steps to reproduce

• open project
• stare at black shadows

Minimal reproduction project

bugreportScene.zip

[PtrMan]

I disabled shadow casting and GI of the meshes for the celestials, this fixes this issue for this scene.

[Zireael07]

Does the issue occur if you keep GI disabled but reenable shadows?

[PtrMan]

Then it's shaded black

[Calinou]

At distances this far away from the world origin, you are expected to use a build with double-precision floats: https://docs.godotengine.org/en/latest/tutorials/physics/large_world_coordinates.html

If you are using official builds, please compile an editor build with precision=double and check if it occurs there.

I was able to reproduce something similar in the large world coordinates demo, but I'm not sure if it still occurs as of 4.2.dev4.

[PtrMan]

I compiled the tag 4.1.1 with precision=double already, else the coordinates would jitter. The unexpected behaviour still occurs compiled that way.

I may run the latest dev commit to see if this behaviour still occurs. It's not to bad because I don't need shadows to/from the celestial bodies anyways.

[Flarkk]

@PtrMan can you raise the near value of your camera to something that is not farther apart than ~1e7 from your far value, and test again if shadows work on distant objects ?

If yes, then this may be solved by #95944

If you can test your project against this PR, it would help.