Using functions from the c# script inside the shader

Question

I'm trying to write a fragment shader that will give a different color depending on the position. For this purpose, I wrote a script that returns the color from given vector3 and I want to call this function inside a shader. Is it possible at all?

My code:

    using System.Collections.Generic;
    using UnityEngine;

    public class CustomLight : MonoBehaviour
    {
      public static List<CustomLight> lights = new List<CustomLight>();

     [Min(0)]
     public float intensity = 1;
        public Color color = Color.white;
        [Min(0)]
        public float radius = 4;
        [Range(0, 1)]
        public float innerRadius = 0;

        public Color GetLight(Vector3 point)
        {
            if (intensity <= 0 || radius <= 0) return Color.clear;

            float value = 0;
            float distanceSqr = (point - transform.position).sqrMagnitude;
            if (distanceSqr >= radius * radius) return Color.clear;

            if (innerRadius == 1) value = 1;
            else
            {
                if (distanceSqr <= radius * radius * innerRadius * innerRadius) value = 1;
                else value = Mathf.InverseLerp(radius, radius * innerRadius, Mathf.Sqrt(distanceSqr));
            }

          return color * intensity * value;
       }

       private void OnEnable()
       {
           if (!lights.Contains(this)) lights.Add(this);
       }
        private void OnDisable()
       {
           lights.Remove(this);
       }
    }

I haven't written any shader yet, because I don't even know where to start. I need the sum of results from all scripts on the scene, then multiply it by the color of the shader.

I apologize for poor English

Answer 1

C# functions run on the CPU while shaders run on the GPU, as such you can't call c# functions from a shader.

You can however access variables passed to the shaders through the materials via Material.SetX methods, which is likely the closest to what your trying to achieve.