protected SVGPoint getEventPoint(NativeEvent event) {
   SVGElement svg = m_svg.cast();
   SVGPoint p = svg.createSVGPoint();
   p.setX(event.getClientX());
   p.setY(event.getClientY());
   return p;
 }
  private void updateScale(double oldScale, double newScale, SVGElement svg, int cx, int cy) {

    double zoomFactor = newScale / oldScale;
    // (x in new coord system - x in old coord system)/x coordinate
    SVGGElement g = m_svgViewPort.cast();

    if (cx == 0) {
      cx = (int) (Math.ceil(svg.getOffsetWidth() / 2.0) - 1);
    }

    if (cy == 0) {
      cy = (int) (Math.ceil(svg.getOffsetHeight() / 2.0) - 1);
    }

    SVGPoint p = svg.createSVGPoint();
    p.setX(cx);
    p.setY(cy);
    p = p.matrixTransform(g.getCTM().inverse());

    SVGMatrix m =
        svg.createSVGMatrix()
            .translate(p.getX(), p.getY())
            .scale(zoomFactor)
            .translate(-p.getX(), -p.getY());
    SVGMatrix ctm = g.getCTM().multiply(m);

    consoleLog("zoomFactor: " + zoomFactor + " oldScale: " + oldScale + " newScale:" + newScale);
    D3.d3()
        .select(m_svgViewPort)
        .transition()
        .duration(1000)
        .attr("transform", matrixTransform(ctm));
  }
    @Override
    public void move() {
      Event event = D3.getEvent().cast();
      SVGPoint p = getEventPoint(event).matrixTransform(m_stateTf);

      SVGElement svg = getContainerElement().cast();
      SVGGElement g = getDraggableElement().cast();
      SVGRect gBox = g.getBBox();

      SVGMatrix m =
          m_stateTf
              .inverse()
              .translate(p.getX() - m_stateOrigin.getX(), p.getY() - m_stateOrigin.getY());

      double mapWidth = gBox.getWidth() * m.getA();
      double mapHeight = gBox.getHeight() * m.getA();

      double boundaryX = calculateBoundsX(mapWidth, svg.getOffsetWidth(), m.getE());

      double boundaryY = calculateBoundsY(mapHeight, svg.getOffsetHeight(), m.getF());

      String matrixTransform =
          "matrix(" + m.getA() + ", " + m.getB() + ", " + m.getC() + ", " + m.getD() + ", "
              + boundaryX + ", " + boundaryY + ")";

      getDraggableElement().setAttribute("transform", matrixTransform);

      // Updating the reference map
      // TODO: this needs to be reworked a little its off
      double viewPortWidth = (getContainerElement().getOffsetWidth() / m.getA()) * 0.4;
      double viewPortHeight = (getContainerElement().getOffsetHeight() / m.getA()) * 0.4;
      m_referenceMapViewport.setAttribute("width", "" + viewPortWidth);
      m_referenceMapViewport.setAttribute("height", "" + viewPortHeight);
      m_referenceMapViewport.setAttribute("x", "" + (-boundaryX * 0.4));
      m_referenceMapViewport.setAttribute("y", "" + (-boundaryY * 0.4));
    }
 private SVGPoint getPoint(int x, int y) {
   SVGPoint p = getSVGElement().createSVGPoint();
   p.setX(x);
   p.setY(y);
   return p;
 }