asp.net动态网站开发教程答案/长春网站建设公司
目录：
1.地毯理解及代码
2.三角形理解及代码
3.地毯+三角形+画图板表示
下图就是我在Java画图板上画出的一个谢尔宾斯地毯
1.地毯理解及代码
制作谢尔宾斯地毯我们需要用到——迭代
理解：
我们可以看出2图是由若干个1图这样的基本图形组成的
同样不管迭代多少次都是由基本图形组成
所以我们的任务就是画出1图这样的基本图形，剩下的就交给迭代去完成
算法
public void draw(Graphics g,int n,int x,int y,int width,int height) {
/**
*x:左上角x坐标，y:左上角y坐标
*width:宽，height：高
*n：迭代层次
*/
g.fillRect(x+width/3,y+height/3,width/3,height/3);
if(n==0)//递归结束条件
return;
n--;
//八个维度
draw(g,n,x, y, width/3, height/3); //1
draw(g,n,x+width/3, y, width/3, height/3);//2
draw(g,n,x+2*(width/3), y, width/3, height/3);//3
draw(g,n,x, y+height/3, width/3, height/3);//4
draw(g,n,x+2*(width/3), y+height/3, width/3, height/3);//5
draw(g,n,x, y+2*(height/3), width/3, height/3);//6
draw(g,n,x+width/3, y+2*(height/3), width/3, height/3);//7
draw(g,n,x+2*(width/3), y+2*(height/3), width/3, height/3);//8
}
2.三角形理解及代码
理解：
原理和地毯一样，都要用到迭代
这是最基础的谢尔宾斯三角形
最外面的大三角形的三个坐标是我们自己取的
我们只要知道六个顶点，画出六条直线，剩下的就可以交给递归了
假设最外层三角形的坐标分别为(x1,y1)(x2,y2)，(x3,y3)
那么三个中点的坐标就是
( (x1+x2)/2, (y1+y2)/2 )
( (x1+x3)/2, (y1+y3)/2 )
( (x3+x2)/2, (y3+y2)/2 )
public void drawtri(Graphics g,int n,int x1,int y1,int x2,int y2,int x3,int y3 ){
g.drawLine(x1,y1,x2,y2);
g.drawLine(x3,y3,x2,y2);
g.drawLine(x1,y1,x3,y3);
g.drawLine((x1+x2)/2,(y1+y2)/2,(x1+x3)/2,(y1+y3)/2);
g.drawLine((x1+x2)/2,(y1+y2)/2,(x2+x3)/2,(y2+y3)/2);
g.drawLine((x3+x2)/2,(y3+y2)/2,(x1+x3)/2,(y1+y3)/2);
if(n==0)
return;
n--;
drawtri(g,n,x1,y1,(x1+x2)/2,(y1+y2)/2,(x1+x3)/2,(y1+y3)/2);
drawtri(g,n,(x1+x2)/2,(y1+y2)/2,x2,y2,(x3+x2)/2,(y3+y2)/2);
drawtri(g,n,(x1+x3)/2,(y1+y3)/2,(x2+x3)/2,(y2+y3)/2,x3,y3);
}
3.地毯+三角形+画图板表示
我们在画图板上加上两个按钮，达到点击按钮
以鼠标点击与落下的线段作为地毯的对角线去绘制地毯
以我们在画图板上点击的三个点去绘制三角形
画图板类：
import javax.swing.JFrame; //窗体
import javax.swing.JButton; //按钮
import java.awt.FlowLayout; //流式布局器
import java.awt.Graphics; //画笔
public class DrawPad {
public static void main(String args[]){
DrawPad dp = new DrawPad();//创建画图板对象
dp.showUI();
}
public void showUI(){
JFrame jf = new JFrame();
DrawPadListener dl = new DrawPadListener();
String[] brnstrs = {"地毯","三角形"};
for (int i = 0; i < brnstrs.length; i++) {
JButton btn = new JButton(brnstrs[i]);
btn.setName(brnstrs[i]);
btn.addActionListener(dl);//按钮添加监听器
jf.add(btn);//将按钮添加到窗体上
}
FlowLayout fl = new FlowLayout();
//流式布局器，使得添加到窗体上的组件从上到下，从左到右排列
//JFrame默认是
jf.setTitle("可视化"); //名称
jf.setSize(800,600); //尺寸
jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //关闭进程
jf.setLayout(fl); //设置流式布局
jf.setResizable(false); //不可以改变窗体大小
jf.setLocationRelativeTo(null);//居中显示
jf.addMouseListener(dl);
jf.setVisible(true); //设置窗体可视
Graphics g = jf.getGraphics(); //取画笔
dl.g = g;
}
}
监听器类：
package 分形;
import java.awt.Color; //颜色
import java.awt.Graphics; //画笔
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;//动作监听器
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener; //鼠标监听器
import java.util.Random;
public class DrawPadListener implements MouseListener, ActionListener{
String btnstr;
Graphics g;
int x1,x2,y1,y2,x3,y3,x4,y4,x5,y5;
int count = 0;
int n = 1;
Random r = new Random();
public void actionPerformed(ActionEvent e){
btnstr = e.getActionCommand();
System.out.println("actionPerformed方法被调用，btnstr为："+btnstr);
}
public void mouseClicked(MouseEvent e){
System.out.println("点击");
}
public void mousePressed(MouseEvent e){
System.out.println("按下");
x1=e.getX();
y1=e.getY();
double a,b,c,d;
if(btnstr.equals("三角形")){
if(count == 0){
x3 = e.getX();
y3 = e.getY();
count++;
}else if(count==1){
x4 = e.getX();
y4 = e.getY();
count++;
}else if(count==2){
x5 = e.getX();
y5 = e.getY();
drawtri(g,n,x3,y3,x4,y4,x5,y5);
count = 0;
}
}
}
public void mouseReleased(MouseEvent e){
System.out.println("释放");
x2=e.getX();
y2=e.getY();//释放点的坐标
if(btnstr.equals("地毯"))
drawcpt(g,n,x1,y1,x2-x1,y2-y1);
}
public void mouseEntered(MouseEvent e){
System.out.println("进入");
}
public void mouseExited(MouseEvent e){
System.out.println("退出");
}
//谢尔宾斯地毯
public void drawcpt(Graphics g,int n,int x,int y,int width,int height) {
g.fillRect(x+width/3,y+height/3,width/3,height/3);
if(n==0)//递归结束条件
return;
n--;
drawcpt(g,n,x, y, width/3, height/3);
drawcpt(g,n,x+width/3, y, width/3, height/3);
drawcpt(g,n,x+2*(width/3), y, width/3, height/3);
drawcpt(g,n,x, y+height/3, width/3, height/3);
drawcpt(g,n,x+2*(width/3), y+height/3, width/3, height/3);
drawcpt(g,n,x, y+2*(height/3), width/3, height/3);
drawcpt(g,n,x+width/3, y+2*(height/3), width/3, height/3);
drawcpt(g,n,x+2*(width/3), y+2*(height/3), width/3, height/3);
}
//谢尔宾斯三角形
public void drawtri(Graphics g,int n,int x1,int y1,int x2,int y2,int x3,int y3 ){
g.drawLine(x1,y1,x2,y2);
g.drawLine(x3,y3,x2,y2);
g.drawLine(x1,y1,x3,y3);
g.drawLine((x1+x2)/2,(y1+y2)/2,(x1+x3)/2,(y1+y3)/2);
g.drawLine((x1+x2)/2,(y1+y2)/2,(x2+x3)/2,(y2+y3)/2);
g.drawLine((x3+x2)/2,(y3+y2)/2,(x1+x3)/2,(y1+y3)/2);
if(n==0)
return;
n--;
drawtri(g,n,x1,y1,(x1+x2)/2,(y1+y2)/2,(x1+x3)/2,(y1+y3)/2);
drawtri(g,n,(x1+x2)/2,(y1+y2)/2,x2,y2,(x3+x2)/2,(y3+y2)/2);
drawtri(g,n,(x1+x3)/2,(y1+y3)/2,(x2+x3)/2,(y2+y3)/2,x3,y3);
}
}