A path transition in JavaFX is used to move a JavaFX node (or object) around a specific path. This is similar to translate transition, as it also moves the object from one position to another. However, the translate transition does not provide a continuous path through which the object moves; which path transition does.

Any JavaFX node, like a 2D or 3D shape, text, image etc., can be moved along any path: straight or curved.

Path Transition in JavaFX

JavaFX offers a PathTransition class to apply the path transition on a JavaFX node. This class belongs to the javafx.animation package. This Transition creates a path animation that moves an object in a certain path and spans its duration.

Path transition does nothing but translate an object in order to relocate it. This translation along a path is done by updating the coordinates of the node in both X and Y directions, and by updating the orientation to OrientationType.ORTHOGONAL_TO_TANGENT, at regular interval. The animated path is defined by the outline of any JavaFX shape.

The PathTransition class offers the following properties to be applied on a node −

duration − The duration of this Transition.

node − The target node of this PathTransition.

orientation − Specifies the upright orientation of node along the path.

path − The shape on which outline the node should be animated.

Example 1

Following is the program which demonstrates Path Transition in JavaFX. Save this code in a file with the name PathTransitionExample.java.

import javafx.animation.PathTransition; 
import javafx.application.Application; 
import static javafx.application.Application.launch; 

import javafx.scene.Group; 
import javafx.scene.Scene; 
import javafx.scene.paint.Color; 

import javafx.scene.shape.Circle; 
import javafx.scene.shape.CubicCurveTo; 
import javafx.scene.shape.MoveTo; 
import javafx.scene.shape.Path; 

import javafx.stage.Stage; 
import javafx.util.Duration;  
    
public class PathTransitionExample extends Application { 
   @Override 
   public void start(Stage stage) {      
      //Drawing a Circle 
      Circle circle = new Circle(); 
      
      //Setting the position of the circle 
      circle.setCenterX(300.0f); 
      circle.setCenterY(135.0f); 
      
      //Setting the radius of the circle 
      circle.setRadius(25.0f); 
      
      //Setting the color of the circle 
      circle.setFill(Color.BROWN); 
      
      //Setting the stroke width of the circle 
      circle.setStrokeWidth(20);     
       
      //Instantiating the path class  
      Path path = new Path(); 
      
      //Creating the MoveTo path element 
      MoveTo moveTo = new MoveTo(100, 150); 
      
      //Creating the Cubic curve path element 
      CubicCurveTo cubicCurveTo = new CubicCurveTo(400, 40, 175, 250, 500, 150); 
      
      //Adding the path elements to Observable list of the Path class 
      path.getElements().add(moveTo); 
      path.getElements().add(cubicCurveTo);        
      
      //Creating a path transition 
      PathTransition pathTransition = new PathTransition(); 
      
      //Setting the duration of the path transition 
      pathTransition.setDuration(Duration.millis(1000)); 
      
      //Setting the node for the transition 
      pathTransition.setNode(circle); 
      
      //Setting the path 
      pathTransition.setPath(path);  
      
      //Setting the orientation of the path 
      pathTransition.setOrientation(PathTransition.OrientationType.
      ORTHOGONAL_TO_TAN GENT); 
      
      //Setting the cycle count for the transition 
      pathTransition.setCycleCount(50); 
      
      //Setting auto reverse value to false 
      pathTransition.setAutoReverse(false); 
    
      //Playing the animation 
      pathTransition.play(); 
         
      //Creating a Group object  
      Group root = new Group(circle); 
         
      //Creating a scene object 
      Scene scene = new Scene(root, 600, 300);   
      
      //Setting title to the Stage 
      stage.setTitle("Path transition example"); 
         
      //Adding scene to the stage 
      stage.setScene(scene); 
         
      //Displaying the contents of the stage 
      stage.show(); 
   } 
   public static void main(String args[]){ 
      launch(args); 
   } 
}

Compile and execute the saved java file from the command prompt using the following commands.

javac --module-path %PATH_TO_FX% --add-modules javafx.controls PathTransitionExample.java 
java --module-path %PATH_TO_FX% --add-modules javafx.controls PathTransitionExample 

Output

On executing, the above program generates a JavaFX window as shown below.

Example 2

Following is an example which transforms a circle along a complex path. Save this code in a file with name PathTransitionExample2.java.

import javafx.animation.PathTransition; 
import javafx.application.Application; 

import javafx.scene.Group; 
import javafx.scene.Scene; 
import javafx.scene.paint.Color; 

import javafx.scene.shape.Circle; 
import javafx.scene.shape.LineTo; 
import javafx.scene.shape.MoveTo; 
import javafx.scene.shape.Path;  

import javafx.stage.Stage; 
import javafx.util.Duration; 
         
public class PathTransitionExample2 extends Application {   
   @Override 
   public void start(Stage stage) {   
      //Drawing a Circle 
      Circle circle = new Circle(); 
      
      //Setting the position of the circle 
      circle.setCenterX(300.0f); 
      circle.setCenterY(135.0f); 
      
      //Setting the radius of the circle 
      circle.setRadius(25.0f); 
      
      //Setting the color of the circle 
      circle.setFill(Color.BROWN); 
      
      //Setting the stroke width of the circle 
      circle.setStrokeWidth(20);     
       
      //Creating a Path 
      Path path = new Path(); 
      
      //Moving to the starting point 
      MoveTo moveTo = new MoveTo(108, 71);               
      
      //Creating 1st line 
      LineTo line1 = new LineTo(321, 161);        
      
      //Creating 2nd line 
      LineTo line2 = new LineTo(126,232); 
      
      //Creating 3rd line 
      LineTo line3 = new LineTo(232,52);        
      
      //Creating 4th line 
      LineTo line4 = new LineTo(269, 250);        
      
      //Creating 5th line 
      LineTo line5 = new LineTo(108, 71);       
      
      //Adding all the elements to the path  
      path.getElements().add(moveTo); 
      path.getElements().addAll(line1, line2, line3, line4, line5);     
      
      //Creating the path transition 
      PathTransition pathTransition = new PathTransition(); 
      
      //Setting the duration of the transition 
      pathTransition.setDuration(Duration.millis(1000));       
      
      //Setting the node for the transition 
      pathTransition.setNode(circle); 
      
      //Setting the path for the transition 
      pathTransition.setPath(path); 
      
      //Setting the orientation of the path 
      pathTransition.setOrientation(
         PathTransition.OrientationType.ORTHOGONAL_TO_TAN GENT); 
      
      //Setting the cycle count for the transition 
      pathTransition.setCycleCount(50); 
      
      //Setting auto reverse value to true 
      pathTransition.setAutoReverse(false); 
      
      //Playing the animation 
      pathTransition.play(); 
             
      //Creating a Group object  
      Group root = new Group(circle); 
         
      //Creating a scene object 
      Scene scene = new Scene(root, 600, 300);  
      
      //Setting title to the Stage 
      stage.setTitle("Path transition example"); 
         
      //Adding scene to the stage 
      stage.setScene(scene); 
         
      //Displaying the contents of the stage 
      stage.show(); 
   }
   public static void main(String args[]){ 
      launch(args); 
   } 
} 

Compile and execute the saved java file from the command prompt using the following commands.

javac --module-path %PATH_TO_FX% --add-modules javafx.controls PathTransitionExample2.java 
java --module-path %PATH_TO_FX% --add-modules javafx.controls PathTransitionExample2 

Output

On executing, the above program generates a JavaFX window as shown below.