Removing noise from noise texture doesn't update it to empty in the editor

[KoBeWi]

Godot version: 3.2.1

Issue description: It shows correctly after running game or reloading scene, so it's minor thing.

[Sslaxx]

If you reload the project in the editor, does it still show as empty?

[KoBeWi]

Yes.

[Schmowser]

I looked a bit into it. So, set_noise applies the noise filter and detaches it respectively:

https://github.com/godotengine/godot/blob/d817be92c2d9edce842ab37ab13117743f8a3bee/modules/opensimplex/noise_texture.cpp#L187-L198

In _update_texture, we get the image from generate_texture and set the texture data afterwards.

https://github.com/godotengine/godot/blob/d817be92c2d9edce842ab37ab13117743f8a3bee/modules/opensimplex/noise_texture.cpp#L181-L182

In _generate_texture, we have the following logic executed for the initial texture and when we clear the Noise from the texture:

https://github.com/godotengine/godot/blob/d817be92c2d9edce842ab37ab13117743f8a3bee/modules/opensimplex/noise_texture.cpp#L143-L145

First, I thought that this "empty" image should be different but it works for initializing the 2D node. In _set_texture_data, we call emit_changed and I wonder if we have to do something to the newly "empty" image such that the change is recognized. Does anyone know where this emit signal is listened to such that the viewport updates the image?

[KoBeWi]

Still valid in 4.4 b3bcb2d