Dynamically changing skybox texture

 using UnityEngine;
 using System.Collections;
 
 public class DynamicTexture : MonoBehaviour 
 {
     public ComputeShader computeShader;
    
     private RenderTexture tex;
     private int kernelHandle;
 
     // Use this for initialization
     void Start () 
     {
         kernelHandle = computeShader.FindKernel("CSMain");
 
         tex = new RenderTexture(256, 256, 24);
         tex.enableRandomWrite = true;
         tex.Create();
 
         this.GetComponent<MeshRenderer>().material.mainTexture = tex;
         this.GetComponent<Skybox>().material.SetTexture("_FrontTex", tex);
        }
     
     // Update is called once per frame
     void Update () 
     {
         computeShader.SetFloat("time", Time.time);
         computeShader.SetTexture(kernelHandle, "Result", tex);
         computeShader.Dispatch(kernelHandle, 256 / 8, 256 / 8, 1);
     }
 }

I'm trying to dynamically change the skybox texture using render texture. When I run the above code, I get a black screen on the skybox. Any help will be appreciated.

Texture compute shader:

 // Each #kernel tells which function to compile; you can have many kernels
 #pragma kernel CSMain
 
 // Create a RenderTexture with enableRandomWrite flag and set it
 // with cs.SetTexture
 RWTexture2D<float4> Result;
 
 uniform float time;
 
 [numthreads(8,8,1)]
 void CSMain (uint3 id : SV_DispatchThreadID)
 {
     // TODO: insert actual code here!
 
     Result[id.xy] = float4(id.x & id.y, (id.x & 15)/15.0 * sin(time), (id.y & 15)/15.0, 0.0);
 }