Repository: godot
Issue: SDFGI produces wildly inaccurate and extreme lighting intensities on Intel Windows drivers
Labels: bug,platform:windows,topic:rendering,confirmed,topic:thirdparty,topic:3d

### Tested versions

Reproducible in Godot 4.2.1 (.NET). Anecdotally this has been an issue for me since SDFGI was released, and has been present for me in every version of Godot 4 I have tried, which were previously non-.NET versions.

### System information

Godot v4.2.1.stable.mono - Windows 10.0.19044 - Vulkan (Forward+) - integrated Intel(R) UHD Graphics 620 (Intel Corporation; 31.0.101.2115) - Intel(R) Core(TM) i5-8265U CPU @ 1.60GHz (8 Threads)

### Issue description

When enabling SDFGI, it doesn't appear how I expect. I am demonstrating this bug in @WickedInsignia's [Godot Garden global illumination test scene](https://github.com/godotengine/godot/issues/63374), as it is a widely available benchmark with many images of how it should look.

**How it should look (from Godot Garden issue linked above)**
![image](https://github.com/godotengine/godot/assets/114206308/282791bd-f765-44ef-aac8-fcba03864f01)

**How it looks for me**
![GI Comparisons](https://github.com/godotengine/godot/assets/114206308/f5c8e52c-122e-4807-99c7-2f7e3754b243)

You may notice a lack of directional shadows in my images. I have the `DirectionalLight3D` visible, so I have no idea why this is but it's not relevant to this bug report.

This type of issue is present any time I have used SDFGI, in every version of Godot 4 I have tried, including v4.2.1.

I have made slight changes to the original Godot Garden project. I added a camera and saved the main scene to view the scene at runtime. This bug was present from the moment I opened the project. I also don't think this is a result of using a project from v4.0a12 in v4.2.1. I have replicated this bug in a fresh 4.2.1 project too, and in many previous versions of Godot 4.

I have a feeling this issue is a result of me using Intel integrated graphics. I haven't been able to find this same bug reported yet, but of course I could have missed it. I'm not doing anything weird — just using SDFGI out of the box from another well-known project, and yet I have such a catastrophic result. I think the only weird thing I'm doing is using an Intel laptop with a rare issue. That said, nothing would delight me more than someone else confirming these results.

Edit: I know SDFGI is going to be replaced in 4.3, so I don't expect major effort to be invested in fixing this likely niche bug.

### Steps to reproduce

1. Download the Godot Garden project from [Issue #63374](https://github.com/godotengine/godot/issues/63374) or the [original Dropbox link](https://www.dropbox.com/s/cgyj111gi8ewp1s/GodotGarden.zip?dl=0) or my [personal project](https://drive.google.com/file/d/10X6hIdX-a5pACAA_bPdUtZA59OI54tu_/view?usp=drive_link).
2. Open in Godot 4.2.1 (Note: the original project is intended for Godot v4.0a12, but I don't think this is relevant as this issue persists in my own projects made in Godot 4.2.1, or any version of Godot 4 I've tried)
3. Notice how bad it looks.

### Minimal reproduction project (MRP)

[Original Godot Garden project Dropbox link](https://www.dropbox.com/s/cgyj111gi8ewp1s/GodotGarden.zip?dl=0) (for Godot v4.0a12)
[My specific project](https://drive.google.com/file/d/10X6hIdX-a5pACAA_bPdUtZA59OI54tu_/view?usp=drive_link) (slight changes mentioned above)