An attempt to make a wrapper that could accept custom Canvas textures as a parameter and turn it into something a material can accept as a uniform

canvas_wrapper.gd

@tool
extends PortableCompressedTexture2D
class_name CanvasWrapper


@export var source_texture:Texture2D:
	get:
		return source_texture
	set(new_value):
		if source_texture != new_value:
			new_value.changed.connect(_on_source_texture_changed)
			if source_texture != null && source_texture.changed.is_connected(_on_source_texture_changed):
				source_texture.changed.disconnect(_on_source_texture_changed)
		source_texture = new_value
		request_update()

@export var update_now:bool:
	get:
		return update_now
	set(new_value):
		update_now = false
		request_update()


var image:Image

func request_update() -> void:
	if source_texture == null:
		return
	if image == null || image.get_size() != Vector2i(source_texture.get_size()):
		image = Image.create(source_texture.get_width(), source_texture.get_height(), true, Image.FORMAT_R8)
	
	image = source_texture.get_image()
	#source_texture.draw()
	#image.generate_mipmaps() # not using mipmaps because this is sampled over time not space
	create_from_image(image, PortableCompressedTexture2D.COMPRESSION_MODE_LOSSLESS)
	emit_changed()

func _on_source_texture_changed() -> void:
	request_update()

func _init():
	request_update()
	

I added the update_now boolean because sometimes it doesn't auto update from changes in the source texture. And it still has problems with AtlasTexture because not all the parameters are showing up in the interface? But it seems okay for noise textures.