// Timer in der standart WndProc...
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch( message ) 
    {    
    case WM_CREATE:

        SetTimer(hWnd, 0, 25, NULL);

    break;

    case WM_TIMER:
    
        // Render deine Szene oder mach sonst was....        
    break;

    case WM_DESTROY:

        KillTimer(hWnd, 0);
        
        PostQuitMessage(0);

    break;

    case WM_CLOSE:
        
        DestroyWindow(hWnd);

    break;

    default:

        return DefWindowProc( hWnd, message, wParam, lParam );
    }

    return 0;
}

void verzögerung(unsigned int iDuration)
{
    unsigned int iEndTime;

    iEndTime= timeGetTime() + iDuration;
    while(timeGetTime() < iEndTime) {}
}