JavaFX 3D 可视化编程四

前面的例子介绍过缩放，但是采用的键盘交互的方式，不太方便，这里介绍基于鼠标中键的物体缩放显示。

主要是添加了鼠标缩放的事件。

代码如下：

package chapt5;

import javafx.application.Application;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.scene.Camera;
import javafx.scene.Group;
import javafx.scene.PerspectiveCamera;
import javafx.scene.Scene;
import javafx.scene.input.KeyEvent;
import javafx.scene.input.ScrollEvent;
import javafx.scene.paint.Color;
import javafx.scene.shape.Box;
import javafx.scene.transform.Rotate;
import javafx.scene.transform.Transform;
import javafx.stage.Stage;

public class Zoom3D extends Application {

    private static final float WIDTH=1400;
    private  static  final  float HEIGHT=800;

    private double anchorX, anchorY;
    private  double anchorAngleX=0;
    private  double anchorAngleY=0;
    private  final DoubleProperty angleX = new SimpleDoubleProperty(0);
    private  final DoubleProperty angleY = new SimpleDoubleProperty(0);

    @Override
    public void start(Stage primaryStage) throws Exception{
        Box box = new Box( 100, 20, 50);

        SmartGroup group = new SmartGroup();
        group.getChildren().add(box);

        Camera camera = new PerspectiveCamera();
        Scene scene =new Scene(group,  WIDTH,  HEIGHT);
        scene.setFill(Color.SILVER);
        scene.setCamera(camera);

        group.translateXProperty().set(WIDTH/2);
        group.translateYProperty().set(HEIGHT/2);
        group.translateZProperty().set(-1200);

        initMouseControl(group, scene, primaryStage);


        primaryStage.addEventHandler(KeyEvent.KEY_PRESSED, event->{
            switch (event.getCode()){
                case W:
                    group.translateZProperty().set(group.getTranslateZ()+50);
                    break;
                case S:
                    group.translateZProperty().set(group.getTranslateZ()-50);
                    break;
                case Q:
                    group.rotateByX(10);
                    break;
                case E:
                    group.rotateByX(-10);
                    break;
                case A:
                    group.rotateByY(10);
                    break;
                case D:
                    group.rotateByY(-10);
                    break;
            }
        });


        primaryStage.setTitle("Camera3D");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    private void initMouseControl(SmartGroup group, Scene scene, Stage stage) {
        Rotate xRotate;
        Rotate yRotate;
        group.getTransforms().addAll(
                xRotate = new Rotate(0, Rotate.X_AXIS),
                yRotate = new Rotate(0, Rotate.Y_AXIS)
        );
        xRotate.angleProperty().bind(angleX);
        yRotate.angleProperty().bind(angleY);

        scene.setOnMousePressed(mouseEvent -> {
            anchorX = mouseEvent.getSceneX();
            anchorY = mouseEvent.getScreenY();
            anchorAngleX = angleX.get();
            anchorAngleY = angleY.get();
        });

        scene.setOnMouseDragged(mouseEvent -> {
            angleX.set(anchorAngleX - (anchorY - mouseEvent.getSceneY()));
            angleY.set(anchorAngleY - (anchorX- mouseEvent.getSceneX()));
        });

        stage.addEventHandler(ScrollEvent.SCROLL, scrollEvent -> {
            double delta = scrollEvent.getDeltaY();
            group.translateZProperty().set(group.getTranslateZ()+delta);
        });
    }


    public static void main(String[] args) {
        launch(args);
    }

    class SmartGroup extends Group{
        Rotate r;
        Transform t = new Rotate();

        void rotateByX(int ang){
            r=new Rotate(ang, Rotate.X_AXIS);
            t = t.createConcatenation(r);
            this.getTransforms().clear();
            this.getTransforms().addAll(t);
        }
        void rotateByY(int ang){
            r=new Rotate(ang, Rotate.Y_AXIS);
            t = t.createConcatenation(r);
            this.getTransforms().clear();
            this.getTransforms().addAll(t);
        }

    }
}

效果如下：