using UnityEngine;
using System.Collections;
using UnityEditor;
[CustomEditor(typeof(SomeScriptType))]
public class MyEditorPlayer : Editor {

    void OnSceneGUI()
    {
        int controlID = GUIUtility.GetControlID(FocusType.Passive);
        switch (Event.current.GetTypeForControl(controlID))
        {
            case EventType.mouseDown:
                GUIUtility.hotControl = controlID;
                Debug.Log("MouseDown");
                Event.current.Use();
                break;
            case EventType.MouseUp:
                GUIUtility.hotControl = 0;
                Event.current.Use();
                break;
        }
    }
}