如何计算子弹的路径

Question

  

我正在尝试完成我的作业，就像飞机射击游戏一样。问题是为什么我的子弹要从图片中心射击？我怎样才能将子弹位置更改为图片的侧面？位置也会改变吗？我创建了2个班级。   我正在尝试完成我的作业，就像飞机射击游戏一样。问题是为什么我的子弹从图片中心射击？我如何将子弹位置更改为图片的侧面，当我旋转位置时也会更改？我创建了2个课程。

public class ShootingGame extends Application{

    private Pane root;
    private GameObject player;
    private List<GameObject> enemies = new ArrayList<>();
    private List<GameObject> bullets = new ArrayList<>();
    private Parent createContent() {
        //create a new pane for player
        root = new Pane();
        root.setPrefSize(600 , 600);
        root.setStyle("-fx-background-color: black");
        //create a player object
        player = new Player();
        player.setVelocity(new Point2D(1,0));
        //add player game object
        addGameObject(player,300,300);
        //create a timer for update when the game start
        AnimationTimer timer = new AnimationTimer() {
            public void handle(long now) {
                onUpdate();
            }
        };  
        //start the timer
        timer.start();

        return root;
    }  

    private void addBullet(Bullet bullet, double x, double y) {
        bullets.add(bullet);
        addGameObject(bullet,x,y);
    }  

    private void addEnemy(GameObject enemy, double x, double y) {
        enemies.add(enemy);
        addGameObject(enemy,x,y);
    }  


    private void addGameObject(GameObject object, double x, double y) {
        object.getView().setTranslateX(x);
        object.getView().setTranslateY(y);
        root.getChildren().add(object.getView());
    }  

    private void onUpdate() {
        player.update();
        for(GameObject bullet:bullets) {
            for(GameObject enemy:enemies) {
                if(bullet.isColliding(enemy)) {
                    bullet.setAlive(false);
                    enemy.setAlive(false);


    root.getChildren().removeAll(bullet.getView(),enemy.getView());
                }
            }
        }  
        bullets.removeIf(GameObject::isDead);
        bullets.forEach(GameObject::update);
        enemies.removeIf(GameObject::isDead);
        enemies.forEach(GameObject::update);
        if(Math.random()<0.02) {
            addEnemy(new Enemy(), 
    Math.random()*root.getPrefHeight(),Math.random()*root.getPrefWidth());
        }

    }  

    //create inner class
    private static class Player extends GameObject{
        Player(){
            super(new ImageView(new Image("file:image/player.png")));

        }
    }  

    //create inner class bullet
    private static class Bullet extends GameObject{
        Bullet(){
            super(new ImageView(new Image("file:image/bullet.png")));
        }
    }  

    //create inner class enemy
    private static class Enemy extends GameObject{
        Enemy(){
            super(new ImageView(new Image("file:image/enemy.png")));
        }
    }  

    public void start(Stage stage) throws Exception{

        btn1.setOnAction(e -> {
            stage.setScene(new Scene(createContent()));
            stage.getScene().setOnKeyPressed(c ->{
                if(c.getCode() == KeyCode.LEFT) {
                    player.rotateLeft();
                }  

                else if(c.getCode() == KeyCode.RIGHT) {
                    player.rotateRight();
                }  

                else if(c.getCode() == KeyCode.SPACE) {
                    Bullet bullet = new Bullet();

      bullet.setVelocity(player.getVelocity().normalize().multiply(5));
 addBullet(bullet,player.getView().getTranslateX(),player.getView().getTranslateY());
                }
            });
        });  

这是第二堂课。

public class GameObject {

    private Node view;
    private Point2D velocity = new Point2D(0,0);
    private boolean alive = true;
    public GameObject(Node view) {
        this.view = view;
    }  

    public Node getView() {
        return view;
    }  

    public boolean isAlive() {
        return alive;
    }  

    public boolean isDead() {
        return !alive;
    }  

    public void setAlive(boolean alive) {
        this.alive = alive;
    }  

    public Point2D getVelocity() {
        return velocity;
    }  


    public void setVelocity(Point2D velocity) {
        this.velocity = velocity;
    }  

    public void update() {
        view.setTranslateX(view.getTranslateX() + velocity.getX());
        view.setTranslateY(view.getTranslateY() + velocity.getY());
    }  

    public double getRotate() {
        return view.getRotate();
    }  

    public void rotateRight() {
        view.setRotate(view.getRotate()+5);
        setVelocity(new Point2D(Math.cos(Math.toRadians(getRotate())),Math.sin(Math.toRadians(getRotate()))));
    }  

    public void rotateLeft() {
        view.setRotate(view.getRotate()-5);
        setVelocity(new Point2D(Math.cos(Math.toRadians(getRotate())),Math.sin(Math.toRadians(getRotate()))));
    }  

    public boolean isColliding(GameObject other) {
        return getView().getBoundsInParent().intersects(other.getView().getBoundsInParent());
    }