GunSystem/Assets/shader/KriptoFX/MeshEffect/Scripts/Editor/MeshRendererEditor.cs

using UnityEngine;
using System.Collections;
using UnityEditor;

[CustomEditor(typeof(PSMeshRendererUpdater))]
public class MeshRendererEditor : Editor
{
    public override void OnInspectorGUI()
    {
        DrawDefaultInspector();

        var myScript = (PSMeshRendererUpdater)target;
        if (GUILayout.Button("Update Mesh Renderer"))
        {
            myScript.UpdateMeshEffect();
        }
    }
}