WndProc proc uses ebx edi esi, hwnd:DWORD, wmsg:DWORD, wparam:DWORD, lparam:DWORD
  switch wmsg
    case WM_INITDIALOG
      invoke SendMessage, hwnd, WM_SETICON, 1, FUNC(LoadIcon, NULL, IDI_ASTERISK)
    case WM_PAINT
      invoke SetPixel, hwnd, 15, 20, 65285
    case WM_CLOSE
      exit_program:
      invoke EndDialog, hwnd, 0
    endsw
  xor eax,eax
ret
WndProc endp