public void onMouseWheel(MouseWheelEvent event) {
ViewPort viewPort = mapPresenter.getViewPort();
if (event.isNorth()) {
if (scrollZoomType == ScrollZoomType.ZOOM_POSITION) {
int index = viewPort.getZoomStrategy().getZoomStepIndex(viewPort.getScale());
viewPort.applyScale(viewPort.getZoomStrategy().getZoomStepScale(index - 1), viewPort.transform(
new Coordinate(event.getX(), event.getY()), RenderSpace.SCREEN, RenderSpace.WORLD));
} else {
int index = viewPort.getZoomStrategy().getZoomStepIndex(viewPort.getScale());
viewPort.applyScale(viewPort.getZoomStrategy().getZoomStepScale(index - 1));
}