Question

我一直在关注youtube关于在java中制作游戏的教程系列，在教程中的某一点，程序必须读取64x64 PNG图像中每个像素的RGB值并创建类的实例因此，当我完成代码时，我得到的只是一个空白屏幕。图像是在paint.net中创建的，我使用eclipse neon 2.我们提前感谢！：）

这是我的代码：

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;

public class Game extends Canvas implements Runnable{

    private static final long serialVersionUID = 1L;

    private boolean isRunning = false;
    private Thread thread;
    private Handler handler;
    private SpriteSheet ss;

    private BufferedImage level = null;
    private BufferedImage sprite_sheet = null;
    private BufferedImage floor = null;


    public Game(){
        new Window(1000, 563, "Wizard Game", this);
        start();

        handler = new Handler();

        this.addKeyListener(new KeyInput(handler));

        BufferedImageLoader loader = new BufferedImageLoader(); 
        level = loader.LoadImage("wizard_level.png");   
        loadLevel(level);
        sprite_sheet = loader.LoadImage("/sprite_sheet.png");

        floor = ss.grabImage(4, 2, 32, 32);
    }

    private void start(){
        isRunning = true;
        thread = new Thread(this);
        thread.start();
    }

    private void stop(){
        isRunning = false;
        try {
            thread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    public void run(){
        this.requestFocus();
        long lastTime = System.nanoTime();
        double amountOfTicks = 60.0;
        double ns = 1000000000 / amountOfTicks;
        double delta = 0;
        long timer = System.currentTimeMillis();
        int frames = 60;
        while(isRunning){
            long now = System.nanoTime();
            delta += (now - lastTime) / ns;
            lastTime = now;
            while(delta >= 1){
                tick();
                delta --;
            }
            if(isRunning)
                render();
            frames ++;

            if(System.currentTimeMillis() - timer > 1000){
                timer += 1000;
                System.out.println("FPS: " + frames);
                frames = 0;
            }
        }
        stop(); 

    }

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

    public void render(){
        BufferStrategy bs = this.getBufferStrategy();
        if(bs == null){
            this.createBufferStrategy(3);
            return;
        }

        Graphics g = bs.getDrawGraphics();

        for(int xx = 0; xx < 30*72; xx += 32){
            for(int yy = 0; yy < 30*72; yy += 32){
                g.drawImage(floor, xx, yy, null);
            }
        }

        handler.render(g);

        g.dispose();
        bs.show();

        }

    private void loadLevel(BufferedImage image){
        int w = image.getWidth();
        int h = image.getHeight();

        for(int xx = 0; xx > w; xx++){
            for(int yy = 0; yy < h; yy++){              
                int pixel = image.getRGB(xx, yy);   
                int red = (pixel >> 16) & 0xff;
                int blue = (pixel >> 8) & 0xff;
                int green = (pixel) & 0xff;

                if(red == 255)
                    handler.addObject(new Block(xx*32, yy*32, ID.Block, ss));

                if(blue == 255)
                    handler.addObject(new Wizard(xx*32, yy*32, ID.Player, handler, ss));

            }
        }
    }

    public static void main(String args[]){
        new Game();

    }

}

Answer 1

以下for循环不会执行..

 for(int xx = 0; xx > w; xx++){

它将循环xx > w，它始终为假（其中xx从0开始，图像的宽度为正）

根据其中的yy循环是正确的，将大于的值更改为小于

 for(int xx = 0; xx < w; xx++){

如果仍未获得预期结果，请记录red和blue的实际值，以查看图像中实际存在哪些颜色元素。仅当像素的红色和蓝色分量为255

时才创建对象

为什么我不能在java和eclipse中读取png图像的rgb值

1 个答案: