// ■干渉縞で遊ぶ
#include "myWin.h"
#include "math.h"
static HDC hbuf; static HBITMAP hBM;
int startX=200, DX=1;
void clearBitmap(){
	SelectObject(hbuf,GetStockObject(NULL_PEN));
	PatBlt(hbuf,0,0,440,220,WHITENESS);
}
void initBitMap(HWND hw){// ビットマップ作成とメモリデバイスコンテキスト作成
	HDC hdc=GetDC(hw); hBM=CreateCompatibleBitmap(hdc,1000,1000);
	hbuf=CreateCompatibleDC(hdc);SelectObject(hbuf,hBM);
	clearBitmap();
	ReleaseDC(hw, hdc);
}
void drawLine(int X1,int Y1,int X2,int Y2){
    MoveToEx(hbuf,X1,Y1,NULL);LineTo(hbuf, X2,Y2);
	
}
void Draw(){
	clearBitmap();
	HPEN pen;
	pen = CreatePen(PS_SOLID,2,0xFF0000);SelectObject(hbuf,pen);
	int XS=20, YS=20,YE=200,YC=100, RY=10;
	for(XS=20;XS<180;XS+=40) for(int i=0;i<=10;i++) 
		if(i%2)	drawLine(XS+i*2   , YC-RY, XS+i*2   , YC+RY);
		else	drawLine(XS+i*2+20, YC-RY, XS+i*2+20, YC+RY);
	DeleteObject(pen);	SetROP2(hbuf,R2_COPYPEN);
	pen = CreatePen(PS_SOLID,2,0x0000FF);SelectObject(hbuf,pen);
	for(XS=startX;XS<startX+200;XS+=4) drawLine(XS, YS,XS, YE);
	DeleteObject(pen);
}
void procLButtonDown(HWND hw, WPARAM wp, LPARAM lp){
	startX--;Draw();
	InvalidateRect(hw,NULL,FALSE);
}
void procRButtonDown(HWND hw, WPARAM wp, LPARAM lp){
	KillTimer(hw,1);
}
void procCreate(HWND hw, WPARAM wp, LPARAM lp){
	SetWindowText(hw,TEXT("干渉縞で遊ぶ"));
	MoveWindow(hw,0,0,260,260,true);
	initBitMap(hw);Draw();
	SetTimer(hw, 1,100,NULL);
	InvalidateRect(hw,NULL,FALSE);
}
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,0,0,440,220,hbuf,0,0,SRCCOPY);
	EndPaint(hw,&ps);
}
void procTimer(HWND hw, WPARAM wp, LPARAM lp){// タイマーイベント
	if(startX<0) DX=1;
	else if(startX>200) DX=-1;
	startX+=DX;
	Draw();
	InvalidateRect(hw,NULL,FALSE);
}
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_LBUTTONDOWN  : procLButtonDown(hw,wp,lp); return 0;
	case WM_RBUTTONDOWN  : procRButtonDown(hw,wp,lp); return 0;
	case WM_TIMER  : procTimer(hw,wp,lp); return 0;
	case WM_PAINT        : procPaint (hw, wp, lp)   ; return 0;
	}
	return DefWindowProc(hw, msg, wp, lp);
}