/*
     24ビットDIB
 2004/ 3/ 8  宍戸　輝光
*/
#include <windows.h>

HINSTANCE g_hInstance;
HWND g_hwMain;

/* DIB用変数 */
BITMAPINFO g_biDIB;
LPBYTE g_lpbyDIB;

int g_iWidth, g_iLength;

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow) {

	MSG  msg;
	WNDCLASS wndclass;

	g_hInstance = hInstance;

	/* DIB用BITMAPINFOをクリア */
	ZeroMemory(&g_biDIB, sizeof(g_biDIB));

	g_iWidth = 255;

	/* DIB用BITMAPINFO設定 */
	g_biDIB.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
	g_biDIB.bmiHeader.biWidth = g_iWidth;
	g_biDIB.bmiHeader.biHeight = 256;
	g_biDIB.bmiHeader.biPlanes = 1;
	g_biDIB.bmiHeader.biBitCount = 24;
	g_biDIB.bmiHeader.biCompression = BI_RGB;

	/* ピクセル列用バッファの横幅算出 */
	if (g_iWidth % 4 == 0) {
		g_iLength = g_iWidth * 3;
	} else {
		g_iLength = g_iWidth * 3 + (4 - (g_iWidth * 3) % 4);
	}

	/* DIBピクセル列用バッファ確保 */
	g_lpbyDIB = (LPBYTE)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, 256 * g_iLength);

	/* (16, 31)に赤い点（0x00ff0000）を打つ */
	g_lpbyDIB[16 * 3 + 31 * g_iLength + 2] = 0xff;

	/* (16, 32)に赤い点（0x00ff0000）を打つ */
	g_lpbyDIB[16 * 3 + 32 * g_iLength + 2] = 0xff;

	/* ウインドウクラス設定 */
	wndclass.style         = CS_HREDRAW | CS_VREDRAW;
	wndclass.lpfnWndProc   = WndProc;
	wndclass.cbClsExtra    = 0;
	wndclass.cbWndExtra    = 0;
	wndclass.hInstance     = hInstance;
	wndclass.hIcon         = LoadIcon(NULL, IDI_APPLICATION);
	wndclass.hCursor       = LoadCursor(NULL, IDC_ARROW);
	wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	wndclass.lpszMenuName  = NULL;
	wndclass.lpszClassName = "24BitDIB";

	RegisterClass(&wndclass);

	/* ウインドウ作成 */
	g_hwMain = CreateWindow("24BitDIB", "24ビットDIB",
	          WS_OVERLAPPEDWINDOW,
	          CW_USEDEFAULT, CW_USEDEFAULT,
			  320, 320, NULL, NULL, hInstance, NULL);

	/* ウインドウを表示 */
	ShowWindow(g_hwMain, iCmdShow);
	UpdateWindow(g_hwMain);

	/* メインループ */
	do {

		/* メッセージ処理 */
		if (GetMessage(&msg,NULL,0,0) == 0) {
			break;
		} else {

			TranslateMessage(&msg);
			DispatchMessage(&msg);

		}

	} while (TRUE);

	/* DIBピクセル列用バッファ解放 */
	HeapFree(GetProcessHeap(), 0, g_lpbyDIB);

	return (int)msg.wParam;

}

/* ウインドウプロシージャー */
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam) {

	HDC hdc;
	PAINTSTRUCT ps;

	switch (iMsg) {

	case WM_PAINT: /* 描画処理 */

		hdc = BeginPaint(hwnd, &ps);

		/* DIB描画 */
		StretchDIBits(hdc, 0, 0, g_iWidth, 256,
	              0, 0, g_iWidth, 256, g_lpbyDIB,
	              &g_biDIB, DIB_RGB_COLORS, SRCCOPY);

		EndPaint(hwnd, &ps);

		return 0;

	case WM_DESTROY: /* 終了処理 */

		PostQuitMessage(0);

		return 0;

	}

	return DefWindowProc (hwnd, iMsg, wParam, lParam) ;

}