What would you need to know to help me write a shader in Godot 4?
To help you write a shader in Godot 4, I would need to know the following information:

Purpose of the shader: What do you want the shader to achieve? Is it for rendering a specific type of material, creating a visual effect, or achieving a specific rendering style?

Target platform: Are you targeting a specific platform or device, such as PC, mobile, or VR? This information can affect the performance and compatibility of the shader.

Technical specifications: Do you have any specific technical requirements or constraints for the shader? For example, do you need to use a specific shading model, implement custom lighting equations, or work within certain performance limitations?

Input and output requirements: What inputs and outputs does your shader need to work with? This could include texture maps, color values, UV coordinates, normals, and other parameters that affect the appearance of the shader.

Godot version: Are you using the latest version of Godot (currently Godot 4) or an earlier version? Shader syntax and functionality can differ between different versions of Godot, so it's important to know which version you're working with.

Prior knowledge and experience: What is your level of experience with shaders and programming in general? This can help me tailor the level of detail and complexity in the instructions provided.

With this information, I can better understand your requirements and provide you with more accurate guidance on how to write a shader in Godot 4.
I want you to make a Toon/Cell Shader with the following specifications:

- One that alters what is rendered
- The target would be Mobile Devices, so Android and iOS
- The only requirement is a limit of, at most, 3 colors
- Color values should suffice, it's a bland (PS1-era) shader
- Yes, Godot 4+
- I have plenty of experience in both, just not in Godot, specifically

is that enough information?