Java分形绘制----山脉绘制

如何绘制一个山脉

构思设计

任意选取三个点，选取一个范围和一个比率，每一个都对这三个点取中点，中点的纵坐标加一个在范围内的随机值，
当完成一次递归之后缩小这个范围即range*rate
连线的时候，将三角形的一个点和这个点的两条边生成的中点相连，最后将三条边的中点相连
所以应该有四个递归调用。

代码实现及注解

package Mountion;

import java.awt.Graphics;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import javax.swing.JFrame;

public class ShowUI {
	List<Shape> list=new ArrayList<>();
	int i=0;
	public void divide(int x1,int x2,int x3,int y1,int y2,int y3,int range,double rate,int times,Graphics g,Shape p){
		if(times==0){
			//画线，构成一个三角形
			g.drawLine(x1, y1, x2, y2);
			g.drawLine(x3, y3, x2, y2);
			g.drawLine(x1, y1, x3, y3);
			return ;
		}
		else{
			times--;
			Random rand=new Random();
			//注意数据需要初始化
			int x4=0,x5=0,x6=0,y4=0,y5=0,y6=0;
			int flag1=0,flag2=0,flag3=0;
			//遍历这个表
			for(Shape s : list) {
				//相等的两种状况
				if((s.pX1()==x1&&s.pX2()==x2&&s.pY1()==y1&&s.pY2()==y2)||(s.pX1()==x2&&s.pX2()==x1&&s.pY1()==y2&&s.pY2()==y1)){
					if(s.show(g)==1){
						//如果这个边已经被使用过了，那么此时说明中点已经生成，只需要读出来中点即可
						x4=s.pX3();
						y4=s.pY3();
						//System.out.println(times+":same:==================size:"+(i++));
					}
					else{
						//如果这条边存在但没有使用,那么生成这个中点，进行更新，其实就是将原来的shape删除掉，加入一个新的。
						x4=(x1+x2)/2;
						y4=(y1+y2)/2+rand.nextInt(range*2)-range;
						//System.out.println(times+"：1");
						list.remove(s);
						p =new Shape(x1,x2,x4,y1,y2,y4,1);
						list.add(p);
					}
					flag1=1;
					break;
				}
				
				
				
			}
			if(flag1==0){
				//System.out.println(times+":before:==================size:"+(i++));
				//如果不存在，这个很简单，只需要构造一个就好了
				x4=(x1+x2)/2;
				y4=(y1+y2)/2+rand.nextInt(range*2)-range;
				p =new Shape(x1,x2,x4,y1,y2,y4,1);
				list.add(p);
			}
			//后面两种情况类似
			for(Shape s : list) {
				if((s.pX1()==x1&&s.pX2()==x3&&s.pY1()==y1&&s.pY2()==y3)||(s.pX1()==x3&&s.pX2()==x1&&s.pY1()==y3&&s.pY2()==y1)){
					if(s.show(g)==1){
						x5=s.pX3();
						y5=s.pY3();
					}
					else{
						x5=(x1+x3)/2;
						y5=(y1+y3)/2+rand.nextInt(range*2)-range;
						list.remove(s);
						p =new Shape(x1,x3,x5,y1,y3,y5,1);
						list.add(p);
					}
					flag2=1;
					break;
				}
			}
			if(flag2==0){
				x5=(x1+x3)/2;
				y5=(y1+y3)/2+rand.nextInt(range*2)-range;
				//System.out.println(times+":before1:==================size:"+(i++));
				p =new Shape(x1,x2,x4,y1,y2,y4,1);
				list.add(p);
			}
			for(Shape s : list){
				if((s.pX1()==x2&&s.pX2()==x3&&s.pY1()==y2&&s.pY2()==y3)||(s.pX1()==x3&&s.pX2()==x2&&s.pY1()==y3&&s.pY2()==y2)){
					if(s.show(g)==1){
						x6=s.pX3();
						y6=s.pY3();
					}
					else{
						x6=(x2+x3)/2;
						y6=(y2+y3)/2+rand.nextInt(range*2)-range;
						list.remove(s);
						p =new Shape(x2,x3,x6,y2,y3,y6,1);
						list.add(p);
					}
					flag3=1;
					break;
				}
			}
			if(flag3==0){
				x6=(x2+x3)/2;
				y6=(y2+y3)/2+rand.nextInt(range*2)-range;
				//System.out.println(times+":before2:==================size:"+(i++));
				p =new Shape(x1,x2,x4,y1,y2,y4,1);
				list.add(p);
			}
			//逐渐缩小范围
			range=(int)(range*rate);
			//将边添加进行，类似一个初始话，标记位为0
			p =new Shape(x1,x4,y1,y4,0);
			list.add(p);
			p =new Shape(x1,x5,y1,y5,0);
			list.add(p);
			p =new Shape(x4,x5,y4,y5,0);
			list.add(p);
			p =new Shape(x2,x4,y2,y4,0);
			list.add(p);
			p =new Shape(x2,x6,y2,y6,0);
			list.add(p);
			p =new Shape(x4,x6,y4,y6,0);
			list.add(p);
			p =new Shape(x3,x5,y3,y5,0);
			list.add(p);
			p =new Shape(x3,x6,y3,y6,0);
			list.add(p);
			p =new Shape(x5,x6,y5,y6,0);
			list.add(p);
			//画四个三角形
			divide(x1,x4,x5,y1,y4,y5,range,rate,times,g,p);
			divide(x2,x4,x6,y2,y4,y6,range,rate,times,g,p);
			
			divide(x3,x5,x6,y3,y5,y6,range,rate,times,g,p);
			divide(x4,x5,x6,y4,y5,y6,range,rate,times,g,p);
		}
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		JFrame moun=new JFrame();
		moun.setSize(1000, 600);
		moun.setLocationRelativeTo(null);
		moun.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		moun.setVisible(true);
		Graphics g=moun.getGraphics();//获取窗体
		int x1=500,x2=100,x3=850;
		int y1=100,y2=400,y3=400;
		int range=200;
		double rate=0.5;
		int times=7;
		ShowUI a=new ShowUI();
		try {
			Thread.sleep(566);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		Shape p = null;
		//System.out.println(100);
		a.divide(x1, x2, x3, y1, y2, y3, range, rate,times,g,p);

	}

}

Shape类

package Mountion;

import java.awt.Graphics;

public class Shape {
	private int x1,x2,x3,y1,y2,y3;
	private int flag;
	//这个构造函数存储的是一个边的两个点，以及这个边生成的中点
	public Shape(int x1,int x2,int x3,int y1,int y2,int y3,int flag){
		this.x1=x1;
		this.x2=x2;
		this.x3=x3;
		this.y1=y1;
		this.y2=y2;
		this.y3=y3;
		this.flag=flag;
	}
//这个构造函数存储的一条边的两个点
	public Shape(int x1,int x2,int y1,int y2,int flag){
		this.x1=x1;
		this.x2=x2;
		this.y1=y1;
		this.y2=y2;
		this.flag=flag;
	}
	//flag标记位，这条边是否被使用过
	public int show(Graphics g) {
		// TODO Auto-generated method stub
		return flag;
	}
	public int pX1(){
		return x1;
	}
	public int pX2(){
		return x2;
	}
	public int pX3(){
		return x3;
	}
	public int pY1(){
		return y1;
	}
	public int pY2(){
		return y2;
	}
	public int pY3(){
		return y3;
	}
}

效果展示