Strange error when changing Spotlight3D Projector texture during runtime, but not during _ready(): ; texture_remove_from_decal_atlas: Parameter "t" is null.

[homhomhomhomhom]

Tested versions

My version:
v4.2.1.stable.official [b09f793]

System information

Godot v4.2.1.stable - Windows 10.0.22631 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 3060 (NVIDIA; 31.0.15.5222) - Intel(R) Core(TM) i7-10700F CPU @ 2.90GHz (16 Threads)

Issue description

Very strange issue when changing Spotlight Projector texture to a different texture during runtime.
Setting the texture in _ready() works fine, but changing the texture after that throws an error, however, it does change the texture and does not crash.

error in question: E 0:00:02:0198 texture_remove_from_decal_atlas: Parameter "t" is null.
<C++ Source> servers/rendering/renderer_rd/storage_rd/texture_storage.cpp:2745 @ texture_remove_from_decal_atlas()

Expected:
No error when changing textures

Got:
Strange error when changing textures

Steps to reproduce

Add a spotlight to your scene

Have a script with a function that changes the spotlight's texture

Press specified button (in my test project it's ui_accept)

See error message when texture changes

Minimal reproduction project (MRP)

BugReproduction.zip

[AwesomeAxolotl]

After thinking the code through a bit, I found the the reason this happens (roughly):
On the change the old texture loses its last reference (RefCounted), and some internal of Light3D still using this will run into a missing reference because the reference already got cleaned up

So the fix would be keeping the current texture in memory by holding it in a var before changing light_projector to a new value or in this example it would also work to (pre)load the textures into the image1 and image2 vars (or an array) like

var image1 = preload("res://bobr.png") var image2 = preload("res://hegodh.png")

var new_image : CompressedTexture2D = image1

[AThousandShips]

Please try with 4.2.2 to confirm this still occurs on a supported version

[homhomhomhomhom]

Issue is also there on 4.2.2

AwesomeAxolotl's fix works tho, altho I'm still not sure it should give the error in the original example