Sprite Sheet help

icons.png 1.42K 18 downloadsHi,

I'm trying to load a SubImage from a BufferedImage in Java and I've had no luck with loading the part of the image, I keep on getting a ton of NullPointerException but I can't figure out what is null and what I'm doing wrong.

I've removed some code because it was wasn't working, At the moment this will load a black screen, but no matter what other code I try to put in, I cannot load the first tile.

Here is the code:

package com.manick.test;


import java.awt.BorderLayout;

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.IOException;


import javax.imageio.ImageIO;

import javax.swing.JFrame;


import com.manick.test.graphics.Screen;

import com.manick.test.graphics.SpriteSheet;


public class Game extends Canvas implements Runnable {

	private static final long serialVersionUID = 1L;


	public static final int HEIGHT = 240;

	public static final int WIDTH = 300;

	public static final int SCALE = 3;


	private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);

	private int[] pixels = ((DataBufferInt) image.getRaster().getDataBuffer()).getData();

	private boolean running = false;

	private int tickCount;

	private Screen screen;

	private SpriteSheet sheet;

	private BufferedImage sprite;


	public void start() {

		running = true;

		new Thread(this).start();

	}


	public void stop() {

		running = false;

	}


	public void init() {

		try {

			screen = new Screen(WIDTH, HEIGHT, new SpriteSheet(ImageIO.read(Game.class.getResourceAsStream("/icons.png"))));

		} catch (IOException e) {

			e.printStackTrace();

		}


		sprite = sheet.getSprite(0, 0, 7, 7);

	}


	public void run() {

		long lastTime = System.nanoTime();

		double unprocessed = 0;

		double nsPerTick = 1000000000.0 / 60.0;

		int frames = 0;

		int ticks = 0;

		long lastTimer1 = System.currentTimeMillis();

		

		init();


		while (running) {

			long now = System.nanoTime();

			unprocessed += (now - lastTime) / nsPerTick;

			lastTime = now;

			boolean shouldRender = true;

			

			init();


			while (unprocessed > 1) {

				ticks++;

				tick();

				unprocessed -= 1;

				shouldRender = true;

			}


			try {

				Thread.sleep(2);

			} catch (InterruptedException e) {

				e.printStackTrace();

			}


			if (shouldRender) {

				frames++;

				render();

			}


			if (System.currentTimeMillis() - lastTimer1 > 1000) {

				lastTimer1 += 1000;

				System.out.println(ticks + " ticks, " + frames + " fps");

				frames = 0;

				ticks = 0;

			}

		}

	}


	public void tick() {

		tickCount++;

	}


	public void render() {

		BufferStrategy bs = getBufferStrategy();

		if (bs == null) {

			createBufferStrategy(3);

			return;

		}

		

		Graphics g = bs.getDrawGraphics();

		g.drawImage(image, 0, 0, getWidth(), getHeight(), null);

		g.drawImage(sprite, WIDTH / 2, HEIGHT / 2, 15, 15, null);

		g.dispose();

		bs.show();

	}


	public static void main(String[] args) {

		Game game = new Game();

		game.setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));

		game.setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));

		game.setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));


		JFrame frame = new JFrame();

		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		frame.setLayout(new BorderLayout());

		frame.add(game);

		frame.pack();

		frame.setResizable(false);

		frame.setLocationRelativeTo(null);

		frame.setVisible(true);


		game.start();

	}

}

package com.manick.test.graphics;


public class Screen {

	int x, y, w, h;

	public SpriteSheet sheet;


	public Screen(int w, int h, SpriteSheet sheet) {

		this.w = w;

		this.h = h;

		this.sheet = sheet;

	}

}

package com.manick.test.graphics;


import java.awt.image.BufferedImage;


public class SpriteSheet {

	BufferedImage image;

	BufferedImage sub;

	

	public SpriteSheet(BufferedImage image) {

		this.image = image;

	}

	

	public BufferedImage getSprite(int x, int y, int w, int h) {

		BufferedImage sub = image.getSubimage(x, y, w, h);

		return sub;

	}

}

thanks.

Edited by floorman, 19 February 2012 - 11:57 AM.
Forgot the image...derp

public void init() { try { sheet = new SpriteSheet(ImageIO.read(new File("icons.png"))); screen = new Screen(WIDTH, HEIGHT, sheet); } catch (IOException e) { e.printStackTrace(); } sprite = sheet.getSprite(0, 0, 7, 7); }