ecmascript:
    function set_jointContacts(val) {
      for(i = 0; i < val.length; i++) {
        if(val[i].geometry1.equals(ground)) {
	  val[i].geometry1 = null;
	  val[i].body1 = null;
	  val[i].bounce = 1;
	}

        if(val[i].geometry2.equals(ground)) {
	  val[i].geometry2 = null;
	  val[i].body2 = null;
	  val[i].bounce = 1;
	}
      }
      correctedContacts = val;
    }

    function activeSensor(val) {
      if(val) {
        indicatorColor.r = 0;
        indicatorColor.g = 1;
        indicatorColor.b = 0;
      }	else {
        indicatorColor.r = 1;
        indicatorColor.g = 0;
        indicatorColor.b = 0;
      }
    }