// 程序:烟火粒子
// 范例文件:FireRock.javaimport java.applet.*;
import java.awt.*;
import java.awt.event.*;public class FireRock extends Applet implements Runnable
{
final int Max = 200;
fparticle p[];
int AppletWidth,AppletHeight,XCenter,YCenter;
Image OffScreen;
Graphics drawOffScreen;
Thread pThread; public void init()
{
setBackground(Color.black); p = new fparticle[Max]; AppletWidth = getSize().width;
AppletHeight = getSize().height; XCenter = (int) (Math.random()*AppletWidth);
YCenter = (int) (Math.random()*AppletHeight); for(int i=0; i<Max; i++)
p[i] = new fparticle(XCenter,YCenter); OffScreen = createImage(AppletWidth,AppletHeight);
drawOffScreen = OffScreen.getGraphics();
} public void start()
{
pThread = new Thread(this);
pThread.start();
} public void stop()
{
pThread = null;
}
public void update(Graphics g)
{
paint(g);
} public void paint(Graphics g)
{
g.drawImage(OffScreen,0,0,this);
} public void run()
{
boolean reset = false;
int i, t =0;
while(true)
{
drawOffScreen.clearRect(0,0,AppletWidth,AppletHeight);
for(i=0; i<Max; i++)
{
if(p[i].X > AppletWidth || p[i].X < 0 ||
p[i].Y > AppletHeight)
{
p[i].state = false;
} if(p[i].state)
{
drawOffScreen.setColor(p[i].color);
drawOffScreen.fillOval(p[i].X,p[i].Y,3,3);
p[i].X += p[i].Vx;
p[i].Y += p[i].Vy;
p[i].Vy += 9*t;
}
} t++; reset = true; for(i=0; i<Max; i++)
{
if(p[i].state)
{
reset = false;
break;
}
} if(reset)
{ XCenter = (int) (Math.random()*AppletWidth);
YCenter = (int) (Math.random()*AppletHeight);
t = 0;
for(i=0; i<Max; i++)
p[i].reset(XCenter,YCenter);
}
repaint();
try {
Thread.sleep(200);
}
catch (InterruptedException e) { }
}
}
}class fparticle
{
boolean state;
int X,Y;
int Vx,Vy;
Color color; public fparticle(int x,int y)
{
X = x;
Y = y;
reset(x,y);
} public void reset(int x, int y)
{
state = true;
X = x;
Y = y;
Vx = (int)(Math.random()*25 - Math.random()*25);
Vy = (int)(Math.random()*25 - Math.random()*25);
color = new Color((int)(Math.random()*255),
(int) (Math.random()*255),
(int) (Math.random()*255));
}
}
// 范例文件:FireRock.javaimport java.applet.*;
import java.awt.*;
import java.awt.event.*;public class FireRock extends Applet implements Runnable
{
final int Max = 200;
fparticle p[];
int AppletWidth,AppletHeight,XCenter,YCenter;
Image OffScreen;
Graphics drawOffScreen;
Thread pThread; public void init()
{
setBackground(Color.black); p = new fparticle[Max]; AppletWidth = getSize().width;
AppletHeight = getSize().height; XCenter = (int) (Math.random()*AppletWidth);
YCenter = (int) (Math.random()*AppletHeight); for(int i=0; i<Max; i++)
p[i] = new fparticle(XCenter,YCenter); OffScreen = createImage(AppletWidth,AppletHeight);
drawOffScreen = OffScreen.getGraphics();
} public void start()
{
pThread = new Thread(this);
pThread.start();
} public void stop()
{
pThread = null;
}
public void update(Graphics g)
{
paint(g);
} public void paint(Graphics g)
{
g.drawImage(OffScreen,0,0,this);
} public void run()
{
boolean reset = false;
int i, t =0;
while(true)
{
drawOffScreen.clearRect(0,0,AppletWidth,AppletHeight);
for(i=0; i<Max; i++)
{
if(p[i].X > AppletWidth || p[i].X < 0 ||
p[i].Y > AppletHeight)
{
p[i].state = false;
} if(p[i].state)
{
drawOffScreen.setColor(p[i].color);
drawOffScreen.fillOval(p[i].X,p[i].Y,3,3);
p[i].X += p[i].Vx;
p[i].Y += p[i].Vy;
p[i].Vy += 9*t;
}
} t++; reset = true; for(i=0; i<Max; i++)
{
if(p[i].state)
{
reset = false;
break;
}
} if(reset)
{ XCenter = (int) (Math.random()*AppletWidth);
YCenter = (int) (Math.random()*AppletHeight);
t = 0;
for(i=0; i<Max; i++)
p[i].reset(XCenter,YCenter);
}
repaint();
try {
Thread.sleep(200);
}
catch (InterruptedException e) { }
}
}
}class fparticle
{
boolean state;
int X,Y;
int Vx,Vy;
Color color; public fparticle(int x,int y)
{
X = x;
Y = y;
reset(x,y);
} public void reset(int x, int y)
{
state = true;
X = x;
Y = y;
Vx = (int)(Math.random()*25 - Math.random()*25);
Vy = (int)(Math.random()*25 - Math.random()*25);
color = new Color((int)(Math.random()*255),
(int) (Math.random()*255),
(int) (Math.random()*255));
}
}
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我刚来 不知道怎么给你们送分 再帮我一下
我真的想谢你