Question

这是我早期的一个跟进问题。我正在制作一个java游戏，它基本上是一个带有角色图像的JFrame，一些健康栏由fillRect（）组成，它们都在背景图像之上。问题是健康栏和角色出现但背景图像不是。

这是Game类的缩短版本，它有main（）和render（）方法：

public class Game extends Canvas implements Runnable{

    public static boolean running = false;
    public Thread gameThread;

    private BufferedImage playerSpriteSheet;
    private ImageManager im;

    private static Player player;
    private static HealthBar healthBars;
    private static BackgroundImage backgroundImage;

    public void init(){
        ImageLoader loader = new ImageLoader();
        playerSpriteSheet = loader.load("/spriteSheet.png");
        SpriteSheet pss = new SpriteSheet(playerSpriteSheet);

        im = new ImageManager(pss);

        backgroundImage = new BackgroundImage("/background.png");
        player = new Player(800, 250, im);
        healthBars = new HealthBar(200, 200);

        this.addKeyListener(new KeyManager());
    }

    public synchronized void start() {
        if(running)return;
        running = true;
        gameThread = new Thread(this);
        gameThread.start();
    }

    public synchronized void stop() {
        if(!running)return;
        running = false;
        try {
            gameThread.join();
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public void run() {
        init();
        long lastTime = System.nanoTime();
        final double amountOfTicks = 60D;
        double ns = 1_000_000_000/amountOfTicks;
        double delta = 0;
        long now = System.nanoTime();

        while(running)
        {
            delta += (now - lastTime)/ns;
            lastTime = now;
            if(delta >= 1)
            {
                tick();
                delta--;
            }
            render();
        }
        stop();
    }

    public void tick() {
        player.tick();
    }

    public void render() {

        BufferStrategy bs = this.getBufferStrategy();
        if(bs == null)
        {
            createBufferStrategy(3); //Use 5 at most
            return;
        }
        Graphics g = bs.getDrawGraphics();

        //RENDER HERE
        backgroundImage.render(g);
        player.render(g);
        healthBars.render(g);


        //END RENDER
        g.dispose();
        bs.show();
    }

    public static void main(String[] args)
    {
        JLabel backgroundImage;
        JLabel controlKeyPanel;
        JLabel statusLabel;

        Game game = new Game();
        game.setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
        game.setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
        game.setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));

        JFrame frame = new JFrame("Title");
        frame.setResizable(false);
        frame.setSize(WIDTH * SCALE, HEIGHT * SCALE);
        frame.setLayout(new BorderLayout());

        backgroundImage = new JLabel(new ImageIcon("/background.png"));

        String htmlButtonGuide = "words";
        controlKeyPanel = new JLabel(htmlButtonGuide);

        statusLabel = new JLabel("label");


        frame.add(backgroundImage, BorderLayout.CENTER);
        frame.add(controlKeyPanel, BorderLayout.EAST);
        frame.add(statusLabel, BorderLayout.SOUTH);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(game);

        frame.setVisible(true);

        game.start();
        //Program seems to continue running after ESC
    }

    public static Player getPlayer() {
        return player;
    }

}

这是BackGroundImage类：

public class BackgroundImage {

    private Image background = null;


    public BackgroundImage(String s) {
        if(s == null)
        {
            background = getImage(s);
        }
    }

    public void render(Graphics g) {
        Graphics2D g2 = (Graphics2D)g;
        g2.drawImage(background, 0, 0, 1200, 600, null);
    }

    public Image getImage(String path) {

        Image tempImage = null;

        File image2 = new File(path);
        try {
            tempImage = ImageIO.read(image2);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return tempImage;
    }
}

我关注render（）方法重用“g”Graphics对象将所有3个东西添加到屏幕上。我被告知不要将轻量级Swing健康棒与重型AWT背景和角色结合起来？谁能指出我正确的方向来获得背景展示？渲染方法应该不关心背景吗？我只需要背景一次。它不需要像健康栏和角色那样不断更新吗？

Answer 1

让我们开始......

backgroundImage = new BackgroundImage("/background.png");

哪个变得......

File image2 = new File(path);

或

File image2 = new File("/background.png");

所以你可以看到它...你能看到这个问题吗？这是请求一个文件驻留在当前驱动器的根位置...不是我认为你想要的......

图像存储在名为＆＃34; res＆＃34;的文件夹中。在主项目文件夹

建议您使用...

backgroundImage = new BackgroundImage("res/background.png");

假设图像不是嵌入资源....

下一步...

public BackgroundImage(String s) {
    if (s == null) {
        background = getImage(s);
    }
}

所以，你只想尝试加载图片时它的引用是null ???

旁注......

frame.setSize(WIDTH * SCALE, HEIGHT * SCALE);是一个坏主意，因为框架有边框占据框架本身的空间。

最好覆盖getPreferredSize的{{1}}方法，并提供您要使用的默认大小值，然后在框架上调用Canvas。这将计算框架的大小作为其优先尺寸的内容加上框架边框要求......

你＆＃34;游戏循环＆＃34;正在疯狂......

pack

基本上，这将尽可能快地运行，并将减少其他线程运行的机会，最终将您的游戏（可能是您的PC）带到它的膝盖

这是简单的＆＃34;运行循环的概念......

while (running) {
    delta += (now - lastTime) / ns;
    lastTime = now;
    if (delta >= 1) {
        tick();
        delta--;
    }
    render();
}

基本上，它会尝试确保每次迭代之间有足够的延迟，以保持您尝试定位的60fps ...而不会使系统挨饿......

没有在Java游戏中显示的背景图像

1 个答案: