コード:
#include <windows.h>
const int WINDOW_WIDTH = 640;
const int WINDOW_HEIGHT = 480;
void MessageLastError(HWND hWnd, const char* title) {
DWORD error = GetLastError();
char buffer[1024] = "";
FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
NULL, error, LANG_USER_DEFAULT, buffer, sizeof(buffer), NULL);
MessageBoxA(hWnd, buffer, title, MB_OK | MB_ICONWARNING);
}
LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam) {
static int mouseX = 0, mouseY = 0;
switch(msg) {
case WM_CREATE:
/* ウィンドウ全体とクライアント領域のサイズの差を考慮してサイズを設定する */
{
RECT windowRect, clientRect;
if (!GetWindowRect(hWnd, &windowRect)) {
MessageLastError(hWnd, "GetWindowRect");
PostMessage(hWnd, WM_CLOSE, 0, 0);
break;
}
if (!GetClientRect(hWnd, &clientRect)) {
MessageLastError(hWnd, "GetClientRect");
PostMessage(hWnd, WM_CLOSE, 0, 0);
break;
}
int borderWidth = (windowRect.right - windowRect.left) - (clientRect.right - clientRect.left);
int borderHeight = (windowRect.bottom - windowRect.top) - (clientRect.bottom - clientRect.top);
if (!SetWindowPos(hWnd, NULL, 0, 0, WINDOW_WIDTH + borderWidth, WINDOW_HEIGHT + borderHeight, SWP_NOMOVE | SWP_NOZORDER)) {
MessageLastError(hWnd, "SetWindowPos");
PostMessage(hWnd, WM_CLOSE, 0, 0);
break;
}
}
/* 約20msおきに更新されるようにする */
if (!SetTimer(hWnd, 0, 20, NULL)) {
MessageLastError(hWnd, "SetTimer");
PostMessage(hWnd, WM_CLOSE, 0, 0);
}
break;
case WM_MOUSEMOVE:
/* マウスの位置の情報を更新する */
mouseX = LOWORD(lParam);
mouseY = HIWORD(lParam);
break;
case WM_TIMER:
/* 再描画させる */
if (wParam == 0) InvalidateRect(hWnd, NULL, FALSE);
break;
case WM_PAINT:
{
/* 描画する */
PAINTSTRUCT ps;
HDC hDC = BeginPaint(hWnd, &ps);
/* ちらつかないように描画バッファを作成する */
HBITMAP hBmp = NULL, hOldBmp = NULL;
HDC hDrawDC = CreateCompatibleDC(hDC);
if (hDrawDC != NULL) {
hBmp = CreateCompatibleBitmap(hDC, WINDOW_WIDTH, WINDOW_HEIGHT);
if (hBmp == NULL) {
DeleteDC(hDrawDC);
hDrawDC = hDC;
} else {
hOldBmp = static_cast<HBITMAP>(SelectObject(hDrawDC, hBmp));
}
} else {
hDrawDC = hDC;
}
/* 画面を黒で塗りつぶす */
RECT all;
all.left = 0; all.right = WINDOW_WIDTH;
all.top = 0; all.bottom = WINDOW_HEIGHT;
FillRect(hDrawDC, &all, static_cast<HBRUSH>(GetStockObject(BLACK_BRUSH)));
/* ラケットの位置を計算する */
const int RACKET_SIZE = 50;
int rpos;
if (mouseX < RACKET_SIZE) rpos = RACKET_SIZE;
else if (mouseX > WINDOW_WIDTH - RACKET_SIZE) rpos = WINDOW_WIDTH - RACKET_SIZE;
else rpos = mouseX;
/* 描画を行う */
RECT racket;
racket.top = 400; racket.bottom = 420;
racket.left = rpos - RACKET_SIZE; racket.right = rpos + RACKET_SIZE;
FillRect(hDrawDC, &racket, static_cast<HBRUSH>(GetStockObject(WHITE_BRUSH)));
/* 描画バッファの内容を反映させる */
if (hBmp != NULL) {
BitBlt(hDC, 0, 0, WINDOW_WIDTH, WINDOW_HEIGHT, hDrawDC, 0, 0, SRCCOPY);
SelectObject(hDrawDC, hOldBmp);
DeleteObject(hBmp);
}
if (hDrawDC != hDC) DeleteDC(hDrawDC);
EndPaint(hWnd, &ps);
}
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, msg, wParam, lParam);
}
return 0;
}
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE /* hPrevInstance */, LPSTR /* lpCmdLine */, int /* nCmdShow */) {
static const char className[] = "CLASS_NAME_9E3FFCCE_B914_481D_A924_35E9D6375745";
WNDCLASSEXA wc = {0};
HWND hwnd;
MSG msg;
wc.cbSize = sizeof(WNDCLASSEX);
wc.lpfnWndProc = WndProc;
wc.hInstance = hInstance;
wc.hCursor = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = (HBRUSH)(COLOR_WINDOW+1);
wc.lpszClassName = className;
if(!RegisterClassExA(&wc)) {
MessageLastError(NULL, "RegisterClassExA");
return 1;
}
hwnd = CreateWindowExA(0, className,
"ブロック崩し風",
(WS_VISIBLE | WS_OVERLAPPEDWINDOW) & ~(WS_MAXIMIZEBOX | WS_THICKFRAME),
CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL);
if(hwnd == NULL) {
MessageLastError(NULL, "CreateWindowExA");
return 1;
}
while(GetMessage(&msg, NULL, 0, 0) > 0) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return msg.wParam;
}