offscreen.java

a java game code for java

package eatbean;

import java.awt.*;
//import java.awt.image.BufferedImage;
//
import eatbean.conf.*;
import eatbean.event.ScreenEvent;
import eatbean.event.ScreenListener;

public class OffScreen {
	private static OffScreen instance = null;
	/** 真正的客户区 */
	private Container screen = null;
	/** 缓冲 */
	private Image offImg = null;
	private Graphics offGraphics = null;
	private int width, height;
	private static Color bgColor = Color.black;
	private ScreenListener screenListener = null;
	private ScreenEvent se = new ScreenEvent(this);
	private Object syncScrObj = new Object();

	private OffScreen(Container c) {
		screen = c;
		width = SysParam.GAME_SCREEN_WIDTH;
		height = SysParam.GAME_SCREEN_HEIGHT + 30;
		//
		//offImg = (Image)new java.awt.image.BufferedImage(width, height, java.awt.image.BufferedImage.TYPE_INT_RGB);
		//
		offImg = c.createImage(width, height);
		offGraphics = offImg.getGraphics();
		offGraphics.setColor(bgColor);
		offGraphics.fillRect(0, 0, width, height);
	}
	public int getWidth() { return width; }
	public int getHeight() { return height; }
	synchronized public static OffScreen getInstance(Container c) {
		if(instance == null) instance = new OffScreen(c);
		return instance;
	}
	//synchronized
	public void drawImage(Image img, int x, int y) {
		offGraphics.drawImage(img, x, y, null);
	}
	//synchronized
	public void fillRect(Color color, int x, int y, int w, int h) {
		Color bakColor = offGraphics.getColor();
		offGraphics.setColor(color);
		offGraphics.fillRect(x, y, w, h);
		offGraphics.setColor(bakColor);
	}
	public void clearRect(int x, int y, int w, int h) {
		offGraphics.setColor(bgColor);
	    offGraphics.fillRect(x, y, w, h);
	}
	public void clear() {
	    clearRect(0, 0, width, height);
	}
	public void setColor(Color c) {
	    offGraphics.setColor(c);
	}
	public void setFont(Font font) {
		offGraphics.setFont(font);
	}
	public void drawString(String s, int x, int y) {
	    offGraphics.drawString(s, x, y);
	}
	synchronized public void flush() {
		Graphics g = screen.getGraphics();
		if(g != null) {
			if(screenListener != null) {
				screenListener.update(se);
			}
			offImg.flush();
			g.drawImage(offImg, 0, 0, null);
		}
	}
	public void addScreenListener(ScreenListener l) {
		synchronized(syncScrObj) {
			if(screenListener != null || l == null) return;
	    	screenListener = l;
		}
	}
	public ScreenListener removeScreenListener() {
		ScreenListener result = null;
		synchronized(syncScrObj) {
			result = screenListener;
		    screenListener = null;
		}
		return result;
	}
}