Skip to content

Instantly share code, notes, and snippets.

@james-d james-d/SunEarthMoon.java
Last active May 18, 2018

Embed
What would you like to do?
Very simple (and not intended to be accurate) model of the sun, earth and moon to demonstrate rotations applied to circles in JavaFX.
import javafx.animation.Animation;
import javafx.animation.KeyFrame;
import javafx.animation.KeyValue;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.transform.Rotate;
import javafx.stage.Stage;
import javafx.util.Duration;
public class SunEarthMoon extends Application {
@Override
public void start(Stage primaryStage) {
final int CIRCLE_CENTER_X = 300 ;
final int CIRCLE_CENTER_Y = 300 ;
final Duration MONTH = Duration.seconds(2);
final Duration YEAR = MONTH.multiply(13);
Circle sun = new Circle(CIRCLE_CENTER_X, CIRCLE_CENTER_Y, 50, Color.GOLD);
Circle earth = new Circle(CIRCLE_CENTER_X + 200, CIRCLE_CENTER_Y, 20, Color.CADETBLUE);
Circle moon = new Circle(CIRCLE_CENTER_X + 240, CIRCLE_CENTER_Y, 5, Color.IVORY);
Group earthAndMoon = new Group(earth, moon);
Pane pane = new Pane(sun, earthAndMoon);
pane.setMinSize(600, 600);
Rotate earthRotate = new Rotate(0, CIRCLE_CENTER_X, CIRCLE_CENTER_Y);
earthAndMoon.getTransforms().add(earthRotate);
Rotate moonRotate = new Rotate(0, CIRCLE_CENTER_X + 200, CIRCLE_CENTER_Y);
moon.getTransforms().add(moonRotate);
Timeline earthTimeline = new Timeline(new KeyFrame(YEAR, new KeyValue(earthRotate.angleProperty(), 360)));
earthTimeline.setCycleCount(Animation.INDEFINITE);
earthTimeline.play();
Timeline moonTimeline = new Timeline(new KeyFrame(MONTH, new KeyValue(moonRotate.angleProperty(), 360)));
moonTimeline.setCycleCount(Animation.INDEFINITE);
moonTimeline.play();
primaryStage.setScene( new Scene(pane, Color.BLACK) );
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.