今天来写k阶科赫雪花的递归实现，(k值需要你手动输入)至于科赫雪花是什么请大家自行百度。
首先来思考这个程序怎么写，当 count = 0 时就应该是一个三角形，这三个点是你一开始就确定的，以后的改变都依据这三个点发展的。当不是0的时候就需要计算相对于这个三角形的9个点，分别是每条边上的两个点，和它对应的三角形第三个顶点。
首先在jframe中添加一个panel，我们需要在这个panel上画图。
大家再来看这个图片，这张图介绍了通过两个点来计算其他三个点的过程。
现在开始在panel中画图：
java" id="highlighter_252477">
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static class showpanel extends jpanel{ int number = 0; public void setnumber(int number) { this.number = number; repaint(); } public void paintcomponent(graphics g) { super.paintcomponent(g);//画一个简单的panel int side =(int)(math.min((int)getwidth(),(int)getheight())*0.8); int high =(int)(side*math.cos(math.toradians(30))); point p1 = new point(getwidth() / 2, 10); point p2 = new point(getwidth() / 2 - side / 2, 10 + high); point p3 = new point(getwidth() / 2 + side / 2, 10 + high); playkochsnowflake(g, number, p1, p2); playkochsnowflake(g, number, p2, p3); playkochsnowflake(g, number, p3, p1); } |
现在开始写递归函数。
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public static void playkochsnowflake(graphics g,int number,point p1,point p2) { if(number == 0){ g.drawline(p1.x, p1.y,p2.x, p2.y); } else{ int deltax = p2.x - p1.x; int deltay = p2.y - p1.y; point x = new point(p1.x + deltax / 3, p1.y + deltay / 3); point y = new point(p1.x + deltax * 2 / 3, p1.y + deltay * 2 / 3); point z = new point( (int)((p1.x + p2.x) / 2 + math.sin(math.toradians(60)) * (p1.y - p2.y) / 3), (int)((p1.y + p2.y) / 2 + math.sin(math.toradians(60)) * (p2.x - p1.x) / 3)); playkochsnowflake(g, number - 1, p1, x); playkochsnowflake(g, number - 1, x, z); playkochsnowflake(g, number - 1, z, y); playkochsnowflake(g, number - 1, y, p2); } } |
然后在主面板中加入一个jtextfield jta 它输入的数据要传入到number中。所以为其添加一个监听器。 已有数据输入就调用其中的setnumber()函数设置number变量。
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jta.addactionlistener(new actionlistener() { public void actionperformed(actionevent arg0) { spl.setnumber(integer.parseint(jta.gettext())); } }); |
所以总体已经完成了，剩下的就是简答的窗体设置。
下面贴一个完整的java代码：
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import java.awt.borderlayout; import java.awt.flowlayout; import java.awt.graphics; import java.awt.point; import java.awt.event.actionevent; import java.awt.event.actionlistener; import javax.swing.jframe; import javax.swing.jlabel; import javax.swing.jpanel; import javax.swing.jtextfield; public class snowflake extends jframe { private jtextfield jta = new jtextfield(5); private showpanel spl = new showpanel(); static class showpanel extends jpanel{ int number = 0; public void setnumber(int number) { this.number = number; repaint(); } public void paintcomponent(graphics g) { super.paintcomponent(g);//画一个简单的panel int side =(int)(math.min((int)getwidth(),(int)getheight())*0.8); int high =(int)(side*math.cos(math.toradians(30))); point p1 = new point(getwidth() / 2, 10); point p2 = new point(getwidth() / 2 - side / 2, 10 + high); point p3 = new point(getwidth() / 2 + side / 2, 10 + high); playkochsnowflake(g, number, p1, p2); playkochsnowflake(g, number, p2, p3); playkochsnowflake(g, number, p3, p1); } public static void playkochsnowflake(graphics g,int number,point p1,point p2) { if(number == 0){ g.drawline(p1.x, p1.y,p2.x, p2.y); } else{ int deltax = p2.x - p1.x; int deltay = p2.y - p1.y; point x = new point(p1.x + deltax / 3, p1.y + deltay / 3); point y = new point(p1.x + deltax * 2 / 3, p1.y + deltay * 2 / 3); point z = new point( (int)((p1.x + p2.x) / 2 + math.sin(math.toradians(60)) * (p1.y - p2.y) / 3), (int)((p1.y + p2.y) / 2 + math.sin(math.toradians(60)) * (p2.x - p1.x) / 3)); playkochsnowflake(g, number - 1, p1, x); playkochsnowflake(g, number - 1, x, z); playkochsnowflake(g, number - 1, z, y); playkochsnowflake(g, number - 1, y, p2); } } } public snowflake() { jpanel panel = new jpanel(); panel.setlayout(new flowlayout()); panel.add(new jlabel("please input the number")); panel.add(jta); add(spl,borderlayout.center); add(panel,borderlayout.south); jta.addactionlistener(new actionlistener() { public void actionperformed(actionevent arg0) { spl.setnumber(integer.parseint(jta.gettext())); } }); } public static void main(string args[]) { snowflake snowflake = new snowflake(); snowflake.setsize(300, 300); snowflake.settitle("snowflake"); snowflake.setlocationrelativeto(null); snowflake.setvisible(true); } } |
效果图：
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://blog.csdn.net/A948433271/article/details/49560071
