Question

我的播放器出现问题。我创建了Player类并在游戏循环的渲染功能中实现了它的draw()方法，但是没有玩家。也没有错误。有人可以帮我找出玩家没有出现的原因吗？

窗口左侧和底部也有一个边框，我无法摆脱它。有人知道吗？

这是游戏类

@SuppressWarnings("serial")
public class Game extends Canvas implements Runnable {

    private static Game _instance;
    private static final String TITLE = "ProjectG";
    public static final int WIDTH = 240;
    public static final int HEIGHT = WIDTH * 3 / 4;
    private static final int SCALE = 4;
    public static final Dimension SIZE = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);

    private static final int UPDATE_RATE = 60;
    private static final int RENDER_RATE = 60;

    private JFrame _frame;
    private Thread _thread;
    private boolean _running = false;

    private int _tps = 0;
    private int _fps = 0;
    private int _totalTicks = 0;

    private BufferedImage image;
    private Graphics2D g;

    private Player player;

    public Game() {
        _instance = this;

        setPreferredSize(SIZE);
        setMinimumSize(SIZE);
        setMaximumSize(SIZE);

        _frame = new JFrame(TITLE);
        _frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        _frame.setLayout(new BorderLayout());
        _frame.add(_instance, BorderLayout.CENTER);
        _frame.pack();

        _frame.setResizable(false);
        _frame.setLocationRelativeTo(null);
        _frame.setVisible(true);

        player = new Player();
    }

    public synchronized void start() {
        _running = true;
        _thread = new Thread(this, TITLE + "_main");
        _thread.start();
    }

    public synchronized void stop() {
        _running = false;

        if (_thread != null) {
            try {
                _thread.join();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public void run() {
        double lastUpdateTime = System.nanoTime();
        double lastRenderTime = System.nanoTime();

        final int ns = 1000000000;
        final double nsPerUpdate = (double) ns / UPDATE_RATE;
        final double nsPerRender = (double) ns / RENDER_RATE;
        final int maxUpdatesBeforeRender = 1;

        int lastSecond = (int) lastUpdateTime / ns;
        int tickCount = 0;
        int renderCount = 0;

        image = new BufferedImage(WIDTH * SCALE, HEIGHT * SCALE, BufferedImage.TYPE_INT_RGB);
        g = (Graphics2D) image.getGraphics();

        while (_running) {
            long currTime = System.nanoTime();
            int tps = 0;

            while ((currTime - lastUpdateTime) > nsPerUpdate && tps < maxUpdatesBeforeRender) {
                update();
                tickCount++;
                _totalTicks++;
                tps++;
                lastUpdateTime += nsPerUpdate;
            }

            if (currTime - lastUpdateTime > nsPerUpdate) {
                lastUpdateTime = currTime - nsPerUpdate;
            }

            float interpolation = Math.min(1.0F, (float) ((currTime - lastUpdateTime) / nsPerUpdate));
            render(interpolation);
            draw();
            renderCount++;
            lastRenderTime = currTime;

            int currSecond = (int) (lastUpdateTime / ns);
            if (currSecond > lastSecond) {
                _tps = tickCount;
                _fps = renderCount;
                tickCount = 0;
                renderCount = 0;
                lastSecond = currSecond;
                System.out.println(_tps + " TPS " + _fps + " FPS");
            }

            while (currTime - lastRenderTime < nsPerRender && currTime - lastUpdateTime < nsPerUpdate) {
                Thread.yield();
                try {
                    Thread.sleep(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                currTime = System.nanoTime();
            }
        }
    }

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

    public void render(float interpolation) {
        BufferStrategy bs = getBufferStrategy();
        if (bs == null) {
            createBufferStrategy(3);
        }

        g.setColor(Color.WHITE);
        g.fillRect(0, 0, WIDTH * SCALE, HEIGHT * SCALE);
        g.setColor(Color.BLACK);
        g.drawString("TPS: " + _fps + " FPS: " + _fps, 10, 20);

        player.draw(g);
    }

    public void draw() {
        Graphics g2 = this.getGraphics();
        g2.drawImage(image, 0, 0, null);
        g2.dispose();
    }
}

这是播放器类

public class Player {

    private int x;
    private int y;
    private int r;

    private int dx;
    private int dy;
    private int speed;

    private boolean left;
    private boolean right;
    private boolean up;
    private boolean down;

    private int lives;

    public Player() {
        x = Game.WIDTH / 2;
        y = Game.HEIGHT / 2;

        dx = 0;
        dy = 0;
        speed = 5;
        lives = 3;
    }

    public void update() {
        if (left) {
            dx = -speed;
        } else if (right) {
            dx = speed;
        } else if (up) {
            dy = -speed;
        } else if (down) {
            dy = speed;
        }

        x += dx;
        y += dy;

        if (x < r)
            x = r;
        if (y < r)
            y = r;
        if (x > Game.WIDTH - r)
            x = Game.WIDTH - r;
        if (y > Game.HEIGHT - r)
            y = Game.HEIGHT - r;

        dx = 0;
        dy = 0;
    }

    public void draw(Graphics2D g) {

        g.setColor(Color.BLACK);
        g.fillOval(x - r, y - r, 2 * r, 2 * r);

        g.setStroke(new BasicStroke(3));
        g.setColor(Color.BLACK.brighter());
        g.drawOval(x - r, y - r, 2 * r, 2 * r);
        g.setStroke(new BasicStroke(1));
    }

    public int getLives() {
        return lives;
    }
}

如果需要，这里是Main类

public class Main {

    private static Game _game;

    public static void main(String[] args) {
        _game = new Game();
        _game.start();
    }
}

Answer 1

如果您从未初始化r，则默认为0，以及如下所示的行。

g.drawOval(x - r, y - r, 2 * r, 2 * r);

实际上不会画任何东西。

简单的播放器不会在Java 2D游戏中显示

1 个答案: