去除自制俄罗斯方块游戏中的闪烁

Question

我已经做了一个俄罗斯方块游戏使用一些帮助从互联网和一些书籍，它似乎工作，几乎如我所希望的。唯一的问题是，当我运行它时，屏幕会在方块掉下来时可怕地闪烁。

我是AWT和swing的新手，因此我经常使用尝试和错误(我知道这很糟糕)来得到我想要的东西。这一次，我不太清楚节目的哪一部分是造成它的。

这是我的密码。对不起，我的代码有点长，我真的不知道问题在哪里发生。(但大多数情况下，它将出现在paint()方法中或计时器中。至少这是我的感受。)

import java.awt.*;
import java.awt.event.*;    
import javax.swing.*;    
import java.applet.*;
import java.io.*;
import sun.audio.*;

public class MatrixBoard extends Frame implements ActionListener{

    int boardHeight = 20;
    int boardWidth  = 10;
    int score = 0;
    int curX = 0, curY = 0;
    int squareWidth;
    int squareHeight;
    Timer timer;
    int sleepTime = 300;
    Shape curPiece;
    Shape.Tetromino[][] board;
    boolean isFallingFinished = false;
    boolean isStarted = false;
    boolean isPaused = false;

    public static void main(String [] args){
        playAudio("C:\\doak.wav");
        MatrixBoard b = new MatrixBoard();
    }

    public static void playAudio(String filename)
    {
        InputStream in = null;
        AudioStream as = null;
        try{
            in = new FileInputStream(filename);
            as = new AudioStream(in);
        }
        catch(Exception e){
            System.out.println("Error!!!");
        }
        AudioPlayer.player.start(as);
    }

    MatrixBoard(){
        setTitle("TETRIS: NEW GAME");
        setFocusable(true);
        setSize(200, 400);
        setVisible(true);
        setBackground(Color.BLACK);
        timer = new Timer(400, this);
        timer.setInitialDelay(10);
        squareWidth = (getWidth())/ boardWidth;
        squareHeight = (getHeight()) / boardHeight;
        curPiece = new Shape();
        board = new Shape.Tetromino[boardWidth][boardHeight];
        addKeyListener(new KeyHandler());
        clearBoard();
        timer.start();
        JOptionPane.showMessageDialog(null, "Press Enter to Start!!!");
        start();
        System.out.println("MatrixBoard() Success!");
    }

    public void clearBoard(){
        for(int i = 0; i < boardWidth; ++i)
            for(int j = 0; j < boardHeight; ++j)
                board[i][j] = Shape.Tetromino.NoShape;
    }

    public void start()
    {
        if (isPaused)
            return;
        clearBoard();
        timer.start();
        timer = new Timer(400, this);
        timer.setInitialDelay(100);
        isStarted = true;
        isFallingFinished = false;
        score = 0;
        repaint();
        newPiece();
        System.out.println("START SUCCESS!");
    }

    private void newPiece(){
        if(!isStarted) return;
        curPiece.generateShape();
        curX = boardWidth / 2;
        curY = 1;

        if(!tryMove(curPiece, curX, curY)){
            curPiece.selectPiece(Shape.Tetromino.NoShape);
            isStarted = false;
            JOptionPane.showMessageDialog(null, "Game Over! Score : " + score);
            isStarted = false;
            int opt = JOptionPane.showConfirmDialog(null, "Try Again?", "Again?", JOptionPane.YES_NO_OPTION);
            if(opt == JOptionPane.YES_NO_OPTION){
                start();
            }
            dispose();
            System.exit(0);
            //new Tetris();
            return;
        }
        dropDown();
        System.out.println("NEW PIECE SUCCESS!");
    }

    private boolean tryMove(Shape newPiece, int newX, int newY){
        for(int i = 0; i < 4; i++){
            int x = newX + newPiece.coords[i][0]; 
            int y = newY + newPiece.coords[i][1]; 
            if(x < 0 || x >= boardWidth || y < 0 || y >= boardHeight){
                System.out.println("FALSE1");
                return false;
            }
            if(board[x][y] != Shape.Tetromino.NoShape){
                System.out.println("FALSE2");
                return false;
            }
        }
        curPiece = newPiece;
        curX = newX;
        curY = newY;
        System.out.println("curX = " + curX + " curY = " + curY);
        System.out.println("TRY MOVE SUCCESS!");
        return true;
    }

    private void dropDown(){
        int newY = curY;
        sleepTime = 300;
        System.out.println("newY = " + newY);
        while(newY < boardHeight){
            if(!tryMove(curPiece, curX, newY+1)){ break;}
            ++newY;
            repaint();
            try {
                Thread.sleep(sleepTime);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        pieceDropped();
        System.out.println("DROPDOWN SUCCESS!");
    }

    private void pieceDropped(){

        for(int i = 0; i < 4; i++){
            int x = curX + curPiece.coords[i][0];
            int y = curY + curPiece.coords[i][1];
            board[x][y] = curPiece.retShape();
            System.out.println("PIECE: at X = " + x + " Y = " + y + "is " + curPiece.retShape().ordinal());
        }
        removeFullLines();
        if(!isFallingFinished) newPiece();
        System.out.println("PIECE DROPPED SUCCESS!");

    }

    public void paint(Graphics g){ 

        Dimension size = getSize();
        int boardTop = (int) size.getHeight() - boardHeight * squareHeight;

        for (int i = 0; i < boardWidth; ++i) {
            for (int j = 0; j < boardHeight; ++j) {
                Shape.Tetromino shape = board[i][j];
                if (shape != Shape.Tetromino.NoShape)
                    drawSquare(g, i * squareWidth,
                               boardTop + j * squareHeight, shape);
            }
        }

        if (curPiece.retShape() != Shape.Tetromino.NoShape) {
           for (int i = 0; i < 4; ++i) {
               int x = curX + curPiece.coords[i][0];
               int y = curY + curPiece.coords[i][1];
               drawSquare(g, x * squareWidth,
                          boardTop + (y - 1) * squareHeight,
                          curPiece.retShape());
           }
       }
   }

    private void drawSquare(Graphics g, int x, int y, Shape.Tetromino shape)
    {
        Color colors[] = { new Color(0, 0, 0), new Color(204, 102, 102), 
            new Color(102, 204, 102), new Color(102, 102, 204), 
            new Color(204, 204, 102), new Color(204, 102, 204), 
            new Color(102, 204, 204), new Color(218, 170, 0)
        };

        Color color = colors[shape.ordinal()];

        g.setColor(color);
        g.fillRect(x + 1, y + 1, squareWidth - 2, squareHeight - 2);

        g.setColor(color.brighter());
        g.drawLine(x, y + squareHeight - 1, x, y);
        g.drawLine(x, y, x + squareWidth - 1, y);

        g.setColor(color.darker());
        g.drawLine(x + 1, y + squareHeight - 1,
                         x + squareWidth - 1, y + squareHeight - 1);
        g.drawLine(x + squareWidth - 1, y + squareHeight - 1,
                         x + squareWidth - 1, y + 1);

    }

    private void removeFullLines(){

        int numLines = 0;

        for(int i = 0; i < boardHeight; i++){
            boolean isLineFull = true;
            for(int j = 0; j < boardWidth; j++){
                System.out.println("i = " + i + " j = " + j);
                if(board[j][i] == Shape.Tetromino.NoShape){
                    System.out.println("Found No Shape here!");
                    isLineFull = false;
                    break;
                }
            }

            System.out.println("IIIIIIIIS LINE : " + isLineFull);

            if(isLineFull){
                numLines++;
                for(int k = i; k > 0; k--){
                    for(int j = 0; j < boardWidth; ++j){
                        board[j][k] = board[j][k-1]; 
                    }
                }
            }
        }

        if(numLines > 0){
            score += numLines;
            repaint();
            newPiece();
        }

    }

    class KeyHandler extends KeyAdapter{
        public void keyPressed(KeyEvent e){
            if(!isStarted || curPiece.retShape() == Shape.Tetromino.NoShape){
                return;
            }
            int keyCode = e.getKeyCode();

            switch(keyCode){
            case KeyEvent.VK_LEFT:
                tryMove(curPiece, curX - 1, curY);
                break;
            case KeyEvent.VK_RIGHT:
                tryMove(curPiece, curX + 1, curY);
                break;
            case KeyEvent.VK_DOWN:
                sleepTime = 10;
                break;
            case KeyEvent.VK_E:
                int opt = JOptionPane.showConfirmDialog(null,"Are you sure?", "Exit", JOptionPane.YES_NO_OPTION);
                if(opt == JOptionPane.YES_OPTION){
                    System.exit(0);
                }
                break;
            case KeyEvent.VK_SPACE:
                tryMove(curPiece.rotateLeft(), curX, curY);
                break;
            default:
                break;
            }
        }
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (isFallingFinished) {
            isFallingFinished = false;
            newPiece();
        } 
    }

}

(据我所知，我的问题可能不符合规定的格式。但我是新来的，需要帮助。因此，我对这个问题中的任何错误表示歉意。)

编辑：

这个问题已经解决了。在接受答案的注释部分中给出的链接之后，我继续并添加了一个类似于链接：http://old.koalateam.com/jml/java/tricks/double-buffering.html中给出的示例的函数。

此外，按照其他建议，我将继承更改为Panel而不是Frame，使我能够实现双缓冲。

非常感谢大家。

Answer 1

通常情况下，屏幕闪烁是由于绘图函数所用的时间比重新绘制屏幕所用的时间长。基本的解决方案是在屏幕外的图像上进行屏幕外缓冲，然后在onto ()方法中，将该图像绘制到屏幕上。

有许多帖子可以谈论这一点。这里有一个：https://today.java.net/pub/a/today/2006/02/23/smooth-moves-solutions.html