Tracer des rectangles

#ifdef UNICODE
#define _T(x) L ## x
typedef unsigned short TCHAR;
#else
#define _T(x) x
typedef char TCHAR;
#endif

#include <windows.h>

HINSTANCE _hThisInstance;              /* Handle du module                    */
HWND _hWnd;                            /* Handle de la fenêtre                */
LPTSTR _lpAppName = _T("Dessin");      /* Nom de l'appli                      */

HBRUSH _hMainBrush = NULL;             /* Brush de la couleur de la fenêtre   */
RECT _rect = { 10, 10, 200, 100 };

WORD __stdcall Err_ShowLast(TCHAR* lpTitle)
{
  DWORD nLastError;
  LPTSTR lpMessageBuffer;

  nLastError = GetLastError();

  FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
                NULL, nLastError, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                (TCHAR*)(void*)&lpMessageBuffer, 0, NULL);

  MessageBox(NULL, lpMessageBuffer, lpTitle, MB_OK | MB_ICONERROR);

  LocalFree(lpMessageBuffer);
  return 1;
}

LRESULT CALLBACK WindowProcedure(HWND hWnd, UINT nMessage, WPARAM wParam, LPARAM lParam)
{
  PAINTSTRUCT ps;             /* Info de dessin                                */
  HDC hDc;                    /* DC de dessin                                  */
  int bHandled;               /* Pour savoir si le message est traité          */
  long nResult;

  nResult = 0;
  bHandled = 0;
  switch (nMessage)
  {
    case WM_PAINT:
      hDc = BeginPaint(hWnd, &ps);
      FillRect(hDc, &_rect, _hMainBrush);
      EndPaint(hWnd, &ps);
      bHandled = 1;
      break;
    case WM_DESTROY:
      /* On signale que le thread va s'arrêter */
      PostQuitMessage(0);
      bHandled = 1;
      break;
  }
  if (! bHandled)
    nResult = DefWindowProc(hWnd, nMessage, wParam, lParam);
  return nResult;
}

BOOL __stdcall CreateMyWindow()
{
  WNDCLASSEX wincl;       /* Classe de la fenêtre utilisée                    */
  int nResult;

  nResult = 0;

  /* Création de la classe de fenêtre */
  wincl.cbSize = sizeof(WNDCLASSEX);
  wincl.style = 0;
  wincl.lpfnWndProc = WindowProcedure;
  wincl.cbClsExtra = 0;
  wincl.cbWndExtra = 0;
  wincl.hInstance = _hThisInstance;
  wincl.hIcon = LoadIcon(NULL, IDI_APPLICATION);
  wincl.hCursor = LoadCursor(NULL, IDC_ARROW);
  wincl.hbrBackground = (HBRUSH)(COLOR_BTNFACE + 1);
  wincl.lpszMenuName = 0;
  wincl.lpszClassName = _lpAppName;
  wincl.hIconSm = NULL;

  /* Enregistrement de la classe */
  if (! RegisterClassEx(&wincl)) goto the_end;

  /* Création de la fenêtre */
  _hWnd = CreateWindowEx(0, _lpAppName, _lpAppName,
                         WS_OVERLAPPED | WS_SYSMENU,
                         CW_USEDEFAULT, CW_USEDEFAULT, 500, 200,
                         HWND_DESKTOP, NULL, _hThisInstance, NULL);
  if (! _hWnd) goto the_end;

  /* Affichage de la fenêtre */
  ShowWindow (_hWnd, SW_SHOW);

  nResult = 1;
the_end:
  return nResult;
}

/**
 * Main
 */
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
  MSG message;                        /* Messages envoyés à l'application     */
  int nResult;

  /* Récupération du handle du module */
  _hThisInstance = hInstance;

  _hMainBrush = CreateSolidBrush(RGB(255, 0, 0));

  if (! CreateMyWindow())
  {
    nResult = Err_ShowLast(_T("Cannot create main window"));
    goto the_end;
  }

  /* Boucle de traitement des messages */
  while (GetMessage(&message, NULL, 0, 0))
  {
    TranslateMessage(&message);
    DispatchMessage(&message);
  }
  nResult = message.wParam;

the_end:
  if (_hMainBrush != NULL)
    DeleteObject(_hMainBrush);
  return nResult;
}