industrialNETworX

It is possible to change the rotation angle at runtime via application or at compile/startup time by replacing the registry key "Rotation" under [HKEY_LOCAL_MACHINE\Drivers\Display\netX] as mentioned in the netX Windows CE BSP documentation.

The following code demonstrates screen rotation at runtime.

  DEVMODE tDevMode = {0};


  tDevMode.dmSize   = sizeof(DEVMODE);

  tDevMode.dmFields = DM_DISPLAYQUERYORIENTATION;

  LONG lQuerySuccess = ChangeDisplaySettingsEx(NULL, &tDevMode, NULL, CDS_TEST, NULL);

  if(ERROR_SUCCESS != lQuerySuccess)

  {

    printf("DM_DISPLAYQUERYORIENTATION failed! (LastError=%u)\n", GetLastError());

  } else

  {

    unsigned long ulSupportedModes = tDevMode.dmDisplayOrientation;

    printf("Screen Rotations supported: \n");

    printf(" - 0°\n");

    if(ulSupportedModes & DMDO_90)

      printf(" - 90°\n");

    if(ulSupportedModes & DMDO_180)

      printf(" - 180°\n");

    if(ulSupportedModes & DMDO_270)

      printf(" - 270°\n");

    tDevMode.dmFields = DM_DISPLAYORIENTATION;

    lQuerySuccess = ChangeDisplaySettingsEx(NULL, &tDevMode, NULL, CDS_TEST, NULL);

    ASSERT(ERROR_SUCCESS == lQuerySuccess);

    DEVMODE tNewMode = {0};

    tNewMode.dmSize   = sizeof(DEVMODE);

    tNewMode.dmFields = DM_DISPLAYORIENTATION;

    tNewMode.dmDisplayOrientation = tDevMode.dmDisplayOrientation;

    do

    {

      switch(tNewMode.dmDisplayOrientation)

      {

      case DMDO_0:

        tNewMode.dmDisplayOrientation = DMDO_90;

        break;

      case DMDO_90:

        tNewMode.dmDisplayOrientation = DMDO_180;

        break;

      case DMDO_180:

        tNewMode.dmDisplayOrientation = DMDO_270;

        break;

      case DMDO_270:

        tNewMode.dmDisplayOrientation = DMDO_0;        

        break;

      }

      if( (tNewMode.dmDisplayOrientation & ulSupportedModes) ||

          (tNewMode.dmDisplayOrientation == DMDO_0) )

      {

        //switch mode if it is supported

        LONG lRes = ChangeDisplaySettingsEx(NULL, &tNewMode, NULL, CDS_RESET, NULL);

        Sleep(1000);

      }

    } while(tNewMode.dmDisplayOrientation != tDevMode.dmDisplayOrientation);

    //switch back to start mode

    ChangeDisplaySettingsEx(NULL, &tNewMode, NULL, CDS_RESET, NULL);

  }