probe pseudocode

YourProbe.cs

class YourProbe : MonoBehaviour {
  public Cubemap m_Probe;
  
  public void Start() {
    SetOntoShaders();
  }
  
  public void OnSelect() {
    // do your "user picks stuff" thing,
    // mip blurring and whatever
    Cubemap b = new Cubemap(...);
    
    m_Probe = b;
    SetOntoShaders();
  }
  
  private void SetOntoShaders ()
  {
    Shader.SetGlobalTexture ("_ReflCube", m_Probe);
  }
}