explosion.java

一個j2me空戰游戲程序很不錯,可以作為學習之用

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
public class explosion
{
	private int[][] Objects;//爆炸状态数组
	//Objects[][0] -----x
	//Objects[][1] -----y
	//Objects[][2] -----是否存活
	//Objects[][3] -----桢指示
	//Objects[][4] -----sprite索引
	public Sprite[] sprite;//内置的Sprite
	public int currentnum;//当前活动的爆炸
	
	public explosion()
	{
		Image img=null;
		sprite=new Sprite[2];
		try
		{
			img = Image.createImage("/explosion.png");
		}
		catch (Exception ex)
	        {}
		sprite[0]=new Sprite(img,32,32);
		
		Objects=new int[20][5];
		currentnum=-1;
	}
	
	public void initObject(int x,int y,int imageindex)//初始化一个爆炸
	{
		int i;
		for(i=0;i<=currentnum;i++)
		{
			if (Objects[i][2]==0) break;
		}
		if (i>currentnum)
		{
			currentnum++;//增加一个
			Objects[currentnum][2] = 1;
			Objects[currentnum][0]=x;
			Objects[currentnum][1]=y;
			Objects[currentnum][3]=4;
			Objects[currentnum][4]=imageindex;
		}
		else
		{
			Objects[i][2] = 1;
			Objects[i][0]=x;
			Objects[i][1]=y;
			Objects[i][3]=4;
			Objects[i][4]=imageindex;
		}
			
         }
	public void update()
	{
		int i;
		for(i=0;i<=currentnum;i++)
		{
			if (Objects[i][2]==0)
			  continue;
                        Objects[i][3]--;
                        if (Objects[i][3]<0) Objects[i][2]=0;
		}
	}
	public void paint(Graphics g)
	{
		
		for(int i=0;i<=currentnum;i++)
		{
			if (Objects[i][2]==0)
			  continue;
			sprite[Objects[i][4]].setPosition(Objects[i][0],Objects[i][1]);
			sprite[Objects[i][4]].setFrame(Objects[i][3]);
		        sprite[Objects[i][4]].paint(g);
		}
	}
	public void reset()
	{
		currentnum=-1;
		for(int i=0;i<Objects.length;i++)
		{
			Objects[i][2]=0;
		}
	}
		
}