*/
  public void histogram (int target, int width, int internal_format, 
    boolean sink) {

    RequestOutputStream o = display.out;
    synchronized (o) {
      begin_render_request (o, 4110, 20);
      o.write_int32 (target);
      o.write_int32 (width);
      o.write_int32 (internal_format);
      o.write_bool (sink);
      o.write_pad (3);
    }
  }