JavaFX scale ScrollPane content centered - javafx

Question

My goal is to have the ScrollPane with some content inside (vbox with some controls) scalable, so that when the scaled content reaches visible bounds, ScrollPane shows horizontal and vertical scroll bars. But there's a catch - in order to do so, I must wrap my content in a Group and by doing so, the scaling is not from the center but rather from the top left corner (0,0) of the ScrollPane, while without wrapping the content of the Group makes the scaling from the center but no scroll bars show. Here is the test application:
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.Slider;
import javafx.scene.layout.Pane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
public class ZoomScrollExample extends Application {
public static void main(String[] args) {
launch(args);
}
#Override
public void start(Stage stage) throws Exception {
Pane root = new Pane();
Scene scene = new Scene(root, 450, 450, Color.WHITE);
stage.setScene(scene);
VBox layout = new VBox();
layout.setMinHeight(400);
layout.setMinWidth(400);
Rectangle r = new Rectangle(200, 200);
r.setStroke(Color.RED);
r.setFill(Color.WHITE);
layout.getChildren().add(r);
layout.setAlignment(Pos.CENTER);
ScrollPane sp = new ScrollPane();
//comment this to get no scroll bars but scaling is centered
Group g = new Group(layout);
sp.setContent(g);
//uncomment this
//sp.setContent(layout);
sp.setPrefSize(450, 450);
Slider s = new Slider();
root.getChildren().add(sp);
root.getChildren().add(s);
s.setMin(100);
s.setMax(200);
// actual scaling
layout.scaleXProperty()
.bind(s.valueProperty().divide(100));
layout.scaleYProperty()
.bind(s.valueProperty().divide(100));
stage.show();
}
}
Is there any (easy) way to have both scroll bars and centered scaling?