OpenGL procedurally generated night nebula shader malfunctioning in Minecraft.

[djmrFunnyMan]

This is a continuation from https://community.intel.com/t5/Developing-Games-on-Intel/Driver-level-bugs-causing-issues-in-Minecraft-amp-OpenGL-shaders/td-p/1664368 which will be split into 3 separate reports.

Issue:

Night Nebula function from Complementary Shaders is broken on certain nights.

This issue also isn't present on Nvidia or AMD cards.
The function that drives this effect is located in nightNebula.glsl (in the attached shaderpacks.zip)
(3 showcase images attached)

Reproduction Steps

Preparation:
- Install Iris & Sodium for 1.21.4 : https://github.com/IrisShaders/Iris/blob/multiloader-new/docs/guide.md
- Unpack the shaderpacks.zip inside the (...)\AppData\Roaming\.minecraft folder
- Unpack the Driver Bug Test.zip inside the \AppData\Roaming\.minecraft\saves folder
- Go into options>video settings>shaderpacks and select "complementary unbound 5.4 + euphoria patches 1.5.2"
- Press apply

Reproduction:
- Open the Driver Bug Test world in-game
- Step on the pressure plate that says "Broken Night Sky"
- Step on any of the pressure plates and you should notice graphical issues on the sky

[karen_intel]

@djmrFunnyMan noted!
Adding to debug queue

Karen