#include "myWin.h"
#include "math.h"
#define BWIDTH  1000
#define BHEIGHT 1000
#define MaxAng 60
#define MaxDsp 90
#define PI 3.14159265358979

static HDC hBuff; static HBITMAP hBM;
void drawLine(double X1, double Y1, double X2, double Y2, int width, unsigned int C) {
	HPEN hpen=CreatePen(PS_SOLID,width,C); SelectObject(hBuff, hpen);
	MoveToEx(hBuff,(int)(X1+0.5), (int)(Y1+0.5), NULL);
	LineTo (hBuff,(int) (X2+0.5), (int)(Y2+0.5));
	DeleteObject(hpen);
}
void clearBitmap(int width, int height){
	SelectObject(hBuff,GetStockObject(NULL_PEN));
	PatBlt(hBuff,0,0,width,height,BLACKNESS);
}
// ビットマップ作成とメモリデバイスコンテキスト作成
void initBitMap(HWND hw, int width, int height){
	HDC hdc=GetDC(hw); hBM=CreateCompatibleBitmap(hdc,width,height);
	hBuff=CreateCompatibleDC(hdc);SelectObject(hBuff,hBM);
	ReleaseDC(hw, hdc);
}
static double curX, curY, Theta; int  CL, LW;
void t_pos(double X, double Y){ curX = X; curY = Y;}
void t_deg (double T){ Theta  = T;}
void t_turn(double T){ Theta += T;}
void setColor(int ID){
	if(ID>60)      CL=RGB(8*(ID-60),4*(ID-60)+125, 8*(ID-60));
	else if(ID>30) CL=RGB(8*(60-ID),0,8*(30-ID));
	else           CL=RGB(8*(30-ID)+255,0,4*(ID-60)+125);
}

void t_forward(double length){
	double TH = Theta * PI / 180;
	double X  = curX+length*cos(TH);
	double Y  = curY+length*sin(TH);
	drawLine((int)(curX), (int)(200 - curY), int(X), int(200 - Y), LW, CL);  
	curX=X; curY=Y;
}
void koch(int n, double TH, double length){
	if(n<=0) { t_forward(length); return; }
	double R1,R2;
	int nn=n -1;double len=length/3;
	R1=len; R2=len*(1-2*cos(TH*PI/180));
	if(R2<0){
	    R2=0;
		R1=len/(2*cos(TH*PI/180));
	}

	koch(nn,TH,len);t_turn(  TH);
	koch(nn,TH,R1);t_turn(-TH);
	//if(R2>0) koch(nn,TH,R2);
	koch(nn,TH,R2);t_turn(-TH);
	koch(nn,TH,R1); t_turn(TH);
	koch(nn,TH,len); 
}
void extKoch(HWND hw){
	LW=4;
	for(int i=MaxDsp;i>=0;i--){
		t_pos(10,-5); t_deg(0); 
		setColor(i);
		koch(7, (double)i, 400);
		InvalidateRect(hw,NULL,TRUE);
	}
	CL=0xFFFFFF;LW=2;
	t_pos(10,-5); t_deg(0); 
	koch(5, 30, 400);

	CL=0x77FFFF;LW=2;
	t_pos(10,-5); t_deg(0); 
	koch(5, 60, 400);
}
void procPaint(HWND hw, WPARAM wp, LPARAM lp){// ビットマップを画面に表示
	PAINTSTRUCT ps; HDC hdc=BeginPaint(hw, &ps);
	BitBlt(hdc,0,0,BWIDTH,BHEIGHT,hBuff,0,0,SRCCOPY);
	EndPaint(hw,&ps);
}
void procCreate(HWND hw, WPARAM wp,LPARAM lp){
	SetWindowText(hw,TEXT("拡張コッホ曲線"));
	MoveWindow(hw,0,0,440,260,TRUE);
	initBitMap(hw,BWIDTH, BHEIGHT);
	clearBitmap(BWIDTH, BHEIGHT);
	extKoch(hw);
	//t_pos(0,0); t_deg(0); koch(5, 200);
	InvalidateRect(hw,NULL,TRUE);
}
LRESULT CALLBACK WndProc(HWND hw, UINT msg, WPARAM wp,LPARAM lp){
	switch(msg){
	case WM_DESTROY : PostQuitMessage(0)  ; return 0;
	case WM_CREATE  : procCreate(hw,wp,lp); return 0;
	case WM_PAINT   : procPaint(hw,wp,lp) ; return 0;
	}
	return DefWindowProc(hw,msg,wp,lp);
}