Is there a maximum of PointLights to add to a Parent?

[Piet Souris]

hi All,

just been adding 6 PointLights to my Group, however, only three show up. I searched through the documentation and on the internet, but I cannot find anything about a maximum. Any help? Or is there some pitfall that I am not aware of?

Thanks!

[Lou Hamers]

I've never used that class, but have you tried removing one of the working ones in real time while the application is running to see if one of the others "activate"?

[Piet Souris]

I've added some togglebuttons to my code, where each togglebutton decides whether the corresponding light is on or off.

Initially, all togglebuttons are selected, so all lights should be on. Only three are visible though, left, right and top. You can see this by dragging over the box and rotating it. If you click on say left, then the left light goes out, and another light goes on.

Another thing that I noticed is that although all togglebuttons are selected, only the left one has a blue border. It almost seems as if these buttons are in a togglegroup, although that is not the case.

Admitted, I am reading the book "Learn JavaFX 17" (and if you want to buy it: buy the e-pub or pdf-version, since the book is a whopping 6 a 7 centimeters thick, making it hard to handle), and started reading at chapter 16, the 3D part, so I may have missed a thing or two

public class CameraProbeersel extends Application {
    
    private static final int WIDTH = 800;
    private static final int HEIGHT = 800;
    private Rotate rotateX = new Rotate(0, Rotate.X_AXIS);
    private Rotate rotateY = new Rotate(0, Rotate.Y_AXIS);
    private DoubleProperty angleX = new SimpleDoubleProperty(0);
    private DoubleProperty angleY = new SimpleDoubleProperty(0);
    double startMouseX = 0;
    double startMouseY = 0;
    double currentMouseX = 0;
    double currentMouseY = 0;
    private PointLight lightLeft;
    private PointLight lightTop;
    private PointLight lightBottom;
    private PointLight lightFront;
    private PointLight lightRight;
    
    
    public static void main(String... args) {
        Application.launch(args);
    }
    
    @Override
    public void start(Stage primaryStage) throws Exception {
        rotateX.angleProperty().bind(angleX);
        rotateY.angleProperty().bind(angleY);
        var box = new Box(100, 100, 100);
        box.getTransforms().addAll(rotateX, rotateY);
        box.setDrawMode(DrawMode.FILL);
        var ph = new PhongMaterial();
        var im = new Image("G:\\Fotos van gezin\\Marc en Erik 1992.jpg");
        ph.setDiffuseMap(im);
        ph.setSpecularMap(im);
        ph.setSpecularColor(Color.ALICEBLUE);
        box.setMaterial(ph);
        
        lightLeft = new PointLight(Color.ALICEBLUE);
        lightLeft.getTransforms().add(new Translate(-100, 0, 0));
        
        lightRight = new PointLight(Color.ORANGE);
        lightRight.getTransforms().add(new Translate(100, 0, 0));
        
        lightFront = new PointLight(Color.WHITE);
        lightFront.getTransforms().add(new Translate(0, 0, -100));
        
        lightTop = new PointLight(Color.WHITE);
        lightTop.getTransforms().add(new Translate(0, -100, 0));
        
        lightBottom = new PointLight(Color.WHITE);
        lightBottom.getTransforms().add(new Translate(0, 100, 0));
        
        var group = new Group();
        group.getChildren().addAll(box, lightLeft, lightRight, lightTop, lightBottom, lightFront);
        
        var subscene = new SubScene(group, 400, 400, true, SceneAntialiasing.BALANCED);
        var camera = new PerspectiveCamera(true);
        camera.translateZProperty().set(-400);
        camera.setNearClip(1);
        camera.setFarClip(1000);

        subscene.setCamera(camera);
        subscene.addEventHandler(MouseEvent.MOUSE_PRESSED, this::processPressed);
        subscene.addEventHandler(MouseEvent.MOUSE_DRAGGED, this::processDragged);
        
        var hbox = new HBox(20);
        hbox.setAlignment(Pos.CENTER);
        
        var buttonLeft = new ToggleButton("left");
        buttonLeft.setSelected(true);
        var buttonRight = new ToggleButton("right");
        buttonRight.setSelected(true);
        var buttonTop = new ToggleButton("top");
        buttonTop.setSelected(true);
        var buttonBottom = new ToggleButton("bottom");
        buttonBottom.setSelected(true);
        var buttonFront = new ToggleButton("front");
        buttonFront.setSelected(true);
        
        hbox.getChildren().addAll(buttonLeft, buttonRight, buttonTop, buttonBottom, buttonFront);
        
        lightBottom.lightOnProperty().bind(buttonBottom.selectedProperty());
        lightTop.lightOnProperty().bind(buttonTop.selectedProperty());
        lightLeft.lightOnProperty().bind(buttonLeft.selectedProperty());
        lightRight.lightOnProperty().bind(buttonRight.selectedProperty());
        lightFront.lightOnProperty().bind(buttonFront.selectedProperty());
        
        var root = new BorderPane();
        root.setTop(hbox);
        root.setCenter(subscene);
        
        Scene scene = new Scene(root, WIDTH, HEIGHT, true);
        scene.setFill(Color.SILVER);
  
        primaryStage.setTitle("5 lights demo, only 3 on at the same time");
        primaryStage.setScene(scene);
        primaryStage.show();
    }
    
    private void processPressed(MouseEvent m) {
        startMouseX = m.getSceneX();
        startMouseY = m.getSceneY();
    }
    
    private void processDragged(MouseEvent m) {
        currentMouseX = m.getSceneX();
        currentMouseY = m.getSceneY();
        var newAngleX = angleX.getValue() + (currentMouseY - startMouseY) / 2;
        var newAngleY = angleY.getValue() - (currentMouseX - startMouseX) / 2;
        startMouseX = currentMouseX;
        startMouseY = currentMouseY;
        angleX.setValue(newAngleX);
        angleY.setValue(newAngleY);
    }
}

[Lou Hamers]

Interesting, yeah I see the same thing you're describing (on Linux so it probably isn't an OS type thing unless you're on the same). Maybe there is a max of three... so you can't just go with an AmbientLight?

[Piet Souris]

The thing is that I could not find anything about a maximum, not in the api and not on the internet. I did use AmbientLight, no problem there. And javafx 18 contains some extra lights as well: directional, spot. Go on with experimenting. Thans for reacting!

By the way: I am on windows.