Question

我想使用RGB值的像素数组（在.render()方法中）从我的精灵表中获取精灵。假设像素阵列保持整个图像的RGB值以便稍后使用，以便从图像中获得各个精灵。有人能解释我怎么能这样做吗？我只是拍了一张黑色的照片。

代码：

import java.awt.Canvas;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import java.io.File;
import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import javax.imageio.ImageIO;
import javax.swing.JFrame;

public class SpritePractice extends Canvas implements Runnable{

private JFrame frame;
public final static int WIDTH = 200, HEIGHT = 200;
public final static int SCALE = 2;
private final static Dimension dimens= new Dimension(WIDTH*SCALE, HEIGHT*SCALE);
private BufferedImage image;
private Graphics g;
private long nanoSecond = 1000000000;
private double tick = nanoSecond/60;
private boolean running = false;
private int pixelsFromImage[];
private int pixel[][];
private static DateFormat dateFormat = new SimpleDateFormat("[" + "yyyy/MM/dd HH:mm:ss"
        +"]");
private static DateFormat dateFormat2 = new SimpleDateFormat("[" + "HH:mm:ss" + "]");

public SpritePractice()
{
    frame = new JFrame("Bomberman");
    frame.setSize(dimens);
    frame.setMinimumSize(dimens);
    frame.setMaximumSize(dimens);
    frame.setResizable(false);
    frame.setLocationRelativeTo(null);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.add(this);
    frame.pack();
    frame.setVisible(true);
    init();
}
public void init()
{
    long startTime = System.nanoTime();
    Calendar cal = Calendar.getInstance();
    System.out.println("START: " + dateFormat.format(cal.getTime()));
}

public void run() 
{
    long now = System.nanoTime();
    long lastTick = System.nanoTime();
    long lastSecond = System.nanoTime();
    int frames = 0;

    while(running)
    {
        now = System.nanoTime();
        Calendar cal = Calendar.getInstance();

        if(now-lastTick >= tick)
        {
            lastTick = now;
            tick();
            try {
                render();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            frames++;
        }   
        if(now-lastSecond >= nanoSecond)
        {
            lastSecond = now;
            System.out.println(dateFormat2.format(cal.getTime()) + "FPS: " + frames);
            frames = 0;
        }
    }
}
public void tick()
{
    //updates values
}
public void render() throws IOException
{
    BufferStrategy bs = getBufferStrategy();
    if(bs==null)
    {
        createBufferStrategy(2);
        return;
    }
    Graphics g = bs.getDrawGraphics();
    BufferedImage spriteSheet = new BufferedImage(WIDTH*2,HEIGHT*2, BufferedImage.TYPE_INT_RGB);

    try
    {
    spriteSheet = ImageIO.read(new File("/res/MarioSpriteSheet.png"));
    }catch (IOException e)
    {

    }
    finally
    {
        pixelsFromImage = ((DataBufferInt) spriteSheet.getRaster().getDataBuffer()).getData();
    }
    BufferedImage sprite = new BufferedImage(WIDTH*2,HEIGHT*2, BufferedImage.TYPE_INT_RGB);
    sprite.getRaster().setPixels(50, 50, 100, 100, pixelsFromImage);

    g.drawImage(sprite,100,100,100,100,null);
    g.dispose();
    bs.show();
    //renders graphics
}
public synchronized void start()
{
    running = true;
    run();
}
public synchronized void stop()
{
    running = false;
}
public static void main(String[] args)
{
    new SpritePractice().start();
}

}

更新（1）：

- 可以通过更改spriteSheet = ImageIO.read(getClass().getResourceAsStream("/res/MarioSpriteSheet.png"));

来阅读文件“MarioSpriteSheet.png”

到spriteSheet = ImageIO.read(getClass().getResourceAsStream("/MarioSpriteSheet.png"));

（图像res文件夹已经在CLASS PATH。

新问题：

Exception in thread "main" java.lang.ClassCastException: java.awt.image.DataBufferByte cannot be cast to java.awt.image.DataBufferInt
at SpritePractice.render(SpritePractice.java:115)
at SpritePractice.run(SpritePractice.java:75)
at SpritePractice.start(SpritePractice.java:125)
at SpritePractice.main(SpritePractice.java:133)

Answer 1

该代码在此抛出异常然后忽略。更改表单的代码

catch (Exception e) { 
     ..

到：

catch (Exception e) { 
    e.printStackTrace(); // very informative! 
    ..

如何使用像素数组从精灵表中获取精灵？

1 个答案: