2004.11.11.

波动文字

//波动文字 bdwz.java
import java.awt.*;

public class bdwz extends java.applet.Applet
implements Runnable {

//变量定义
String str = null;
int direction = 1;
int horizontalRadius = 10;
int verticalRadius = 10;
Thread runner = null;
char theChars[];
int phase = 0;
Image offScreenImage;
Graphics offScreenG;

//初始化小程序
public void init() {
String paramStr = null;
str = getParameter("text");
paramStr = getParameter("direction");
setBackground(Color.black);
if (paramStr != null)
direction = Integer.parseInt(paramStr);
paramStr = getParameter("horizontalRadius");
if (paramStr != null)
horizontalRadius = Integer.parseInt(paramStr);
paramStr = getParameter("verticalRadius");
if (paramStr != null)
verticalRadius = Integer.parseInt(paramStr);
setFont(new Font("TimesRoman",Font.BOLD,36));
if (str == null) {
str = "波动文字 2004.11.11.";
}
resize(30+25*str.length()+2*horizontalRadius,80+2*verticalRadius);

theChars = new char [str.length()];
str.getChars(0,str.length(),theChars,0);
offScreenImage = createImage(this.size().width,this.size().height);
offScreenG = offScreenImage.getGraphics();
offScreenG.setFont(new Font("TimesRoman",Font.BOLD,36));
}

//启动小程序
public void start() {
if(runner == null) {
runner = new Thread(this);
runner.start();
}
}

//停止小程序
public void stop() {
if (runner != null) {
runner.stop();
runner = null;
}
}

//运行小程序
public void run() {
while (runner != null) {
try {
Thread.sleep(120);
}
catch (InterruptedException e) { }
repaint();
}
}

//更新界面
public void update(Graphics g) {
int x, y;
double angle;
offScreenG.setColor(Color.black);
offScreenG.fillRect(0,0,this.size().width,this.size().height);
phase+=direction;
phase%=8;
for(int i=0;i<str.length();i++) {
angle = ((phase-i*direction)%8)/4.0*Math.PI;

//水平方向的运动
x = 20+25*i+(int) (Math.cos(angle)*horizontalRadius); 

//竖直方向的运动
y = 60+ (int) (Math.sin(angle)*verticalRadius); 

// 第一个字的颜色是蓝色
if (i==0 || theChars[i-1]==' ') 
offScreenG.setColor(Color.blue);
else

//其它字为红色
offScreenG.setColor(Color.orange); 
offScreenG.drawChars(theChars,i,1,x,y);
}
paint(g);
}

//画屏函数
public void paint(Graphics g) {
g.drawImage(offScreenImage,0,0,this);
}
}