// stdafx.cpp : source file that includes just the standard includes
//	Fractral.pch will be the pre-compiled header
//	stdafx.obj will contain the pre-compiled type information

#include "stdafx.h"

//Couch曲線的畫法
void Couch(CDC *pDC,int x1,int y1,int x2,int y2,int n)
{
	//pDC是畫圖的設備上下文的指針
	//x1,y1,x2,y2是起始的兩點
	//其中參數(shù)n是遞歸的層數(shù)
	int x3,y3,x4,y4,x5,y5;
	//以下是根據(jù)空間幾何計算出來的坐標
	x3=x1+(x2-x1)/3;
	y3=y1+(y2-y1)/3;
	x4=x1+(x2-x1)*2/3;
	y4=y1+(y2-y1)*2/3;
	x5=x3+(x4-x3)/2+int(sqrt(3)*(y4-y3)/2);
	y5=y3-int(sqrt(3)*(x4-x3)/2)+(y4-y3)/2;
	//遞歸最后一層,遞歸的出口
	if(n==1)
	{
		pDC->MoveTo(x1,y1);
		pDC->LineTo(x3,y3);
		pDC->LineTo(x5,y5);
		pDC->LineTo(x4,y4);
		pDC->LineTo(x2,y2);
	}
	else
	{
		//遞歸畫圖
		Couch(pDC,x1,y1,x3,y3,n-1);
		Couch(pDC,x3,y3,x5,y5,n-1);
		Couch(pDC,x5,y5,x4,y4,n-1);
		Couch(pDC,x4,y4,x2,y2,n-1);
	}
}

//斯賓斯基簍墊的畫法
void Floor(CDC *pDC,int x1, int y1,int x2,int y2,int x3,int y3,int n)
{
	//pDC是畫圖的設備上下文的指針
	//x1,y1,x2,y2,x3,y3是起始的三角形的三點坐標
	//其中參數(shù)n是遞歸的層數(shù)
	int x11,x22,x33,y11,y22,y33;
	//以下是根據(jù)空間幾何計算出來的坐標
	x11=(x2+x3)/2;
	y11=(y2+y3)/2;
	x22=(x1+x3)/2;
	y22=(y1+y3)/2;
	x33=(x1+x2)/2;
	y33=(y1+y2)/2;

	pDC->MoveTo(x11,y11);
	pDC->LineTo(x22,y22);
	pDC->MoveTo(x11,y11);
	pDC->LineTo(x33,y33);
	pDC->MoveTo(x22,y22);
	pDC->LineTo(x33,y33);
	//遞歸最后一層,遞歸的出口
	if(n==1)
	{
		pDC->MoveTo(x11,y11);
		pDC->LineTo(x22,y22);
		pDC->LineTo(x33,y33);
		pDC->LineTo(x11,y11);
	}
	else
	{
		//遞歸畫圖
		Floor(pDC,x1,y1,x33,y33,x22,y22,n-1);
		Floor(pDC,x33,y33,x2,y2,x11,y11,n-1);
		Floor(pDC,x22,y22,x11,y11,x3,y3,n-1);
	}
}

//分形矩形的畫法
void Rect(CDC *pDC,int x1,int y1,int x2,int y2,int n)
{
	//pDC是畫圖的設備上下文的指針
	//x1,y1,x2,y2是起始矩形坐標
	//其中參數(shù)n是遞歸的層數(shù)
	int x3,y3,x4,y4,x5,y5,x6,y6;
	//以下是根據(jù)空間幾何計算出來的坐標
	x3=x1+(x2-x1)/3;
	y3=y1+(y2-y1)/3;
	x4=x1+(x2-x1)*2/3;
	y4=y1+(y2-y1)*2/3;
	x5=x3+(y4-y3);
	y5=y3-(x4-x3);
	x6=x4-(y3-y4);
	y6=y4+(x3-x4);
	
	pDC->MoveTo(x1,y1);
	pDC->LineTo(x3,y3);
	pDC->MoveTo(x4,y4);
	pDC->LineTo(x2,y2);
	//遞歸最后一層,遞歸的出口
	if(n==1)
	{		
		pDC->MoveTo(x1,y1);
		pDC->LineTo(x3,y3);
		pDC->LineTo(x5,y5);
		pDC->LineTo(x6,y6);
		pDC->LineTo(x4,y4);
	}
	else
	{
		//遞歸畫圖
		Rect(pDC,x3,y3,x5,y5,n-1);
		Rect(pDC,x5,y5,x6,y6,n-1);
		Rect(pDC,x6,y6,x4,y4,n-1);
	}
}

//分形樹的畫法，其中參數(shù)n是遞歸的層數(shù)
void Tree(CDC *pDC,int x1,int y1,int x2,int y2,int n)
{
	//pDC是畫圖的設備上下文的指針
	//x1,y1,x2,y2是起始矩形坐標
	//其中參數(shù)n是遞歸的層數(shù)
	int x3,y3,x4,y4,x5,y5;
	//以下是根據(jù)空間幾何計算出來的坐標
	x3=x1+(x2-x1)/3;
	y3=y1+(y2-y1)/3;
	x4=x3+int((x1-x3)*cos(5*pi/6))-int((y1-y3)*sin(5*pi/6));
	y4=y3+int((x1-x3)*sin(5*pi/6))+int((y1-y3)*cos(5*pi/6));
	x5=x3+int((x1-x3)*cos(5*pi/6))+int((y1-y3)*sin(5*pi/6));
	y5=y3-int((x1-x3)*sin(5*pi/6))+int((y1-y3)*cos(5*pi/6));

	pDC->MoveTo(x1,y1);
	pDC->LineTo(x2,y2);
	//遞歸最后一層,遞歸的出口
	if(n==1)
	{
		pDC->MoveTo(x3,y3);
		pDC->LineTo(x4,y4);
		pDC->MoveTo(x3,y3);
		pDC->LineTo(x5,y5);
	}
	else
	{
		//遞歸畫圖
		Tree(pDC,x3,y3,x2,y2,n-1);
		Tree(pDC,x3,y3,x4,y4,n-1);
		Tree(pDC,x3,y3,x5,y5,n-1);
	}
}