#include<windows.h>
#include<math.h>

#define WIDTH	197
#define HEIGHT	100

#define BIT		8
#define COLOR	((DWORD)pow(2,BIT))

LRESULT CALLBACK WindowProc(HWND hWnd,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
	HDC hdc;
	PAINTSTRUCT ps;
	static LPBYTE lpPixel;
	static LPBITMAPINFO lpBmpInfo;
	int x,y,i;
	static int length;

	switch(uMsg) {
		case WM_CREATE:
			//4の倍数に補正
			if(WIDTH%4) length=WIDTH+(4-WIDTH%4);
			else length=WIDTH;

			lpPixel=(LPBYTE)HeapAlloc(GetProcessHeap(),HEAP_ZERO_MEMORY,
				length*HEIGHT+sizeof(BITMAPINFO)+sizeof(RGBQUAD)*(COLOR-1));
			lpBmpInfo=(LPBITMAPINFO)(lpPixel+length*HEIGHT);
			
			//カラーテーブルを設定する
			for(i=0;i<COLOR;i++){ 				lpBmpInfo->bmiColors[i].rgbBlue=i%128;
				lpBmpInfo->bmiColors[i].rgbGreen=128-i%128;
				lpBmpInfo->bmiColors[i].rgbRed=i%256;
			}
			//DIBの情報を設定する
			lpBmpInfo->bmiHeader.biSize=sizeof(BITMAPINFOHEADER);
			lpBmpInfo->bmiHeader.biWidth=WIDTH;
			lpBmpInfo->bmiHeader.biHeight=HEIGHT;
			lpBmpInfo->bmiHeader.biPlanes=1;
			lpBmpInfo->bmiHeader.biBitCount=BIT;
			lpBmpInfo->bmiHeader.biCompression=BI_RGB;
			//lpBmpInfo->bmiHeader.biClrUsed=COLOR;
			
			//描画
			for(i=0,y=25;y<=50;y++){
				for(x=25;x<=50;x++){
					lpPixel[x+y*length]=(++i)%COLOR;
				}
			}
			return 0;
		case WM_DESTROY:
			HeapFree(GetProcessHeap(),0,lpPixel);
			PostQuitMessage(0);
			return 0;
		case WM_PAINT:
			hdc=BeginPaint(hWnd,&ps);
			//表画面へ転送
			StretchDIBits(hdc,0,0,WIDTH,HEIGHT,
				0,0,WIDTH,HEIGHT,lpPixel,lpBmpInfo,DIB_RGB_COLORS,SRCCOPY);
			EndPaint(hWnd,&ps);
			return 0;
	}
	return DefWindowProc(hWnd,uMsg,wParam,lParam);
}

int WINAPI WinMain(
	HINSTANCE hInstance,HINSTANCE hPrevInstance,PSTR lpCmdLine,int nCmdShow)
{
	WNDCLASS wc;
	MSG msg;

	wc.style		 = CS_HREDRAW | CS_VREDRAW;
	wc.lpfnWndProc	 = WindowProc;
	wc.cbClsExtra	 = 0;
	wc.cbWndExtra	 = 0;
	wc.hInstance	 = hInstance;
	wc.hIcon		 = LoadIcon(NULL,IDI_APPLICATION);
	wc.hCursor		 = LoadCursor(NULL,IDC_ARROW);
	wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wc.lpszMenuName	 = NULL;
	wc.lpszClassName = __FILE__;
	if(!RegisterClass(&wc)) return 0;

	HWND hWnd=CreateWindow(
		__FILE__,"8ビットDIBを作る",
		WS_OVERLAPPEDWINDOW | WS_VISIBLE,
		CW_USEDEFAULT,CW_USEDEFAULT,
		CW_USEDEFAULT,CW_USEDEFAULT, 
		NULL,NULL,hInstance,NULL);
	if(hWnd==NULL) return 0;

	BOOL bRet;
	while((bRet=GetMessage(&msg,NULL,0,0))!=0){
		if(bRet==-1) break;
		DispatchMessage(&msg);
	}

	return (int)msg.wParam;
}