2D游戏中的Java swing渲染现象

我目前正在做我的第一个跳跃跑游戏。最初的部分已经可以正常工作了，但我仍然会遇到一个“bug”，当我的“colums”移动时会出现。只有当“移动速度”为1时，才会发生这种情况。我通过更改以下内容将其固定：

private void recycleColums() {

if (cList.get(0).getX() + cList.get(0).getWidth() <= 0) {

    cList.remove(0);
    cList.add(7, new Column(7 + 1, false, cList.get(6).getX()));

    frame.add(cList.get(7));

  }
}

---

到底是什么问题？什么是错误？这些列不应该在那里吗？问题是我的列之间的这些小间隙。（我在图中用蓝色箭头标记了它们）所以当你说“列”时，你是指黑色和绿色的瓷砖/地吗？确切地说，我不知道如何称呼它们，否则^^^必须在AWT事件调度线程中创建和操作Swing对象。您正在另一个线程中修改它们，这就是您看到奇怪行为的原因。见和。

...
public class Column extends JPanel {

JPanel floor;
JPanel grass;

Random rand = new Random();

private static final long serialVersionUID = 1L;

public final static int WIDTH = Board.WIDTH / 6;
public final int HEIGHT = Board.HEIGHT;

private int position;

public final static int FLOOR_H = WIDTH;

public Column(int pos, boolean init) {

    this.position = pos;

    setBounds((WIDTH * position) - WIDTH, 0, WIDTH, HEIGHT);
    setLayout(null);
    setBackground(Color.WHITE);

    floor = new JPanel();
    floor.setLayout(null);
    floor.setBackground(Color.BLACK);

    if (init) {

        floor.setBounds(0, HEIGHT - FLOOR_H, WIDTH, FLOOR_H);

    } else {

        floor.setBounds(0,
                (HEIGHT - (FLOOR_H + (FLOOR_H * rand.nextInt(2) / 2))),
                WIDTH, FLOOR_H * 2);
    }

    grass = new JPanel();
    grass.setBounds(0, 0, WIDTH, 10);
    grass.setBackground(Color.GREEN);

    floor.add(grass);
    add(floor);

   }
}

private void recycleColums() {

if (cList.get(0).getX() + cList.get(0).getWidth() <= 0) {

    cList.remove(0);
    cList.add(7, new Column(7 + 1, false, cList.get(6).getX()));

    frame.add(cList.get(7));

  }
}

public Column(int pos, boolean init, int lastX) {

    this.position = pos;


    setLayout(null);
    setBackground(Color.WHITE);

    floor = new JPanel();
    floor.setLayout(null);
    floor.setBackground(Color.BLACK);

    if (init) {

        setBounds((WIDTH * position) - WIDTH, 0, WIDTH, HEIGHT);
        floor.setBounds(0, HEIGHT - FLOOR_H, WIDTH, FLOOR_H);

    } else {

        setBounds(lastX + WIDTH, 0, WIDTH, HEIGHT);
        floor.setBounds(0,
                (HEIGHT - (FLOOR_H + (FLOOR_H * rand.nextInt(2) / 2))),
                WIDTH, FLOOR_H * 2);
    }