5 Light
This chapter describes the Light API included in the JavaFX 3D graphics library.
Light is now also defined as a node in the scene graph. A default light is provided if the set of active lights contained in the scene is empty. Each light contains a set of affected nodes. If a set of nodes is empty, all nodes on the scene (or subscene) are affected. If a Parent node is in that set of nodes, then all of its children are also affected.
Light interacts with the geometry of a Shape3D object and its material to provide rendering result. Currently, there are two types of light sources:
-
AmbientLight- a light source that seems to come from all directions. -
PointLight- a light source that has a fixed point in space and radiates light equally in all directions away from itself.
Example 5-1 shows the Light Class Hierarchy.
Example 5-1 Light Class Hierarchy
javafx.scene.Node
javafx.scene.LightBase (abstract)
javafx.scene.AmbientLight
javafx.scene.PointLight
Creating and Using Light
To create point light and add it to the Scene, do the following:
PointLight light = new PointLight();
light.setColor(Color.RED);
Use the following to add light to the scene graph:
Group lightGroup = new Group();
lightGroup.getChildren().add(light);
root.getChildren().add(lightGroup);
Rotate the light 45 degrees with the following line of code:
light.rotate(45);
To move the lightGroup and have light moves with it, use something similar to the following code.
lightGroup.setTranslateZ(-75);
The setTranslateZ() method sets the value of the property translateZ, which is set to -75 in the example code above. This value will be added to any translation defined by the transforms ObservableList and layoutZ.
Example 5-2 shows a code snippet taken from the MSAAApp.java application, which illustrates how to use the PointLight API.
Example 5-2 MSAAApp.java Code Snippet Using PointLight API
...
PointLight light = new PointLight(Color.WHITE);
light.setTranslateX(50);
light.setTranslateY(-300);
light.setTranslateZ(-400);
PointLight light2 = new PointLight(Color.color(0.6, 0.3, 0.4));
light2.setTranslateX(400);
light2.setTranslateY(0);
light2.setTranslateZ(-400);
AmbientLight ambientLight = new AmbientLight(Color.color(0.2, 0.2, 0.2));
node.setRotationAxis(new Point3D(2, 1, 0).normalize());
node.setTranslateX(180);
node.setTranslateY(180);
root.getChildren().addAll(setTitle(title), ambientLight,
light, light2, node);
...
