Vulkan Forward+: Scaling a decal non-uniformly causes clustering artifacts to appear

[JohnMeadow1]

Godot version

v4.0.rc5.official

System information

Win 10, Vulkan API 1.3.224, RTX 4070 Ti

Issue description

Decal create clustering artifacts when non uniform Y size and Y scale:

Decal_bug_thing.mp4

Steps to reproduce

Decal size non-uniform (2,1,2)
Set scale non uniform (1,0.25,1)

Reproduction.mp4

Minimal reproduction project

Decal_Clustering.zip

[WuotanStudios]

HI,
i can confirm this.
This issue only appears when using the transform - scaling.
Here a video how the issue looks like, if i use the transform-scale parameters:
https://twitter.com/WuotanStudios/status/1648257531590983688?s=20

If only the Decal-Size is used, everything works perfectly.

[Calinou]

I can confirm this on 4.0.2 (Linux, GeForce RTX 4090 with NVIDIA 530.41.03). This only seems to occur with non-uniform scaling, not uniform scaling. This occurs both when the scale is positive or negative.

This doesn't occur when using Forward Mobile, as it doesn't use clustering.