How should I organize a complex visual shader with reused values?

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1

Godot Version

4.4.1

Question

What is the best way to organize a visual shader in the node/graph editor that has a whole lot of values that need to get used in many ways? I have a shader that does some UV parallaxing, and the final output of the parallax section is making a lot of spaghetti:

image
image408×669 57.6 KB

Ideally, I’d just set a variable instead of connecting everything visually, but I’m not sure the right way to do that in the visual shader editor. Should I be using a Varying to keep track of things even though they’d both be set and got within the same fragment shader? Is there a way to use something like a ParameterRef node, but to retrieve a value calculated elsewhere in the fragment shader? Should I somehow be using Expression nodes to get and set values via Godot’s shading language?

2

I have only just started playing with shaders (and they are amazing) but I did it like this.

In the shader you set a variable like this:

uniform vec2 camera_offset;
uniform float camera_zoom;

Then you can update these whenever you like like this:

# I set this one up in the ready function for example
BACKGROUND.material.set_shader_parameter("camera_zoom", CAMERA.zoom.x)

# I call this in the _process function
func _process(_delta: float) -> void:
    BACKGROUND.material.set_shader_parameter("camera_offset", CAMERA.global_position)

Where BACKGROUND is a ColorRect that I have applied the shader material to.

Hope that helps.

3

I’d love to be able to do that. My question is how to set variables in the visual shader editor depicted in my screenshot.

4

Oh, I thought you wanted wanted to do this in code instead of using the visual editor. Sorry. I was sure you said something like that in your original post. Anyway, my bad, I have no idea about the visual editor, sorry.

Darn. I was delighted to help with a shader question as well. :frowning:
They are just so amazing! It has been a real eye opener for me.

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