今天來寫k階科赫雪花的遞歸實(shí)現(xiàn)，(k值需要你手動(dòng)輸入)至于科赫雪花是什么請(qǐng)大家自行百度。
首先來思考這個(gè)程序怎么寫，當(dāng) count = 0 時(shí)就應(yīng)該是一個(gè)三角形，這三個(gè)點(diǎn)是你一開始就確定的，以后的改變都依據(jù)這三個(gè)點(diǎn)發(fā)展的。當(dāng)不是0的時(shí)候就需要計(jì)算相對(duì)于這個(gè)三角形的9個(gè)點(diǎn)，分別是每條邊上的兩個(gè)點(diǎn)，和它對(duì)應(yīng)的三角形第三個(gè)頂點(diǎn)。
首先在jframe中添加一個(gè)panel，我們需要在這個(gè)panel上畫圖。
大家再來看這個(gè)圖片，這張圖介紹了通過兩個(gè)點(diǎn)來計(jì)算其他三個(gè)點(diǎn)的過程。
現(xiàn)在開始在panel中畫圖：
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);//畫一個(gè)簡單的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); } |
現(xiàn)在開始寫遞歸函數(shù)。
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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個(gè)jtextfield jta 它輸入的數(shù)據(jù)要傳入到number中。所以為其添加一個(gè)監(jiān)聽器。 已有數(shù)據(jù)輸入就調(diào)用其中的setnumber()函數(shù)設(shè)置number變量。
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jta.addactionlistener(new actionlistener() { public void actionperformed(actionevent arg0) { spl.setnumber(integer.parseint(jta.gettext())); } }); |
所以總體已經(jīng)完成了，剩下的就是簡答的窗體設(shè)置。
下面貼一個(gè)完整的java代碼：
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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);//畫一個(gè)簡單的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); } } |
效果圖：
以上就是本文的全部內(nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持服務(wù)器之家。
原文鏈接：https://blog.csdn.net/A948433271/article/details/49560071
