The Vector4 comparator couldn't know that q==-q. PiperOrigin-RevId: 498947861 Change-Id: Ife9efeb369c794eedbef80829e40057794a334ee
This also fixes a sensor data reading bug: previously, _sensorIndex was multiplied by 3 by MjEngineTool. PiperOrigin-RevId: 451699887 Change-Id: I864bcbf8159857764854b25311a26ec5672125d9