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    • CommentTimeSep 11th 2020 edited

    Hi there
    In my new project I need to programatically take a picture of the machine desktop at regular intervals - but have no idea how to do this. So, just wondering if a function capable to take a screenshot and save it to disk already exists in NTK? -or- If someone has already developed such kind of code and would like to share it? Any help would be appreciated.

    • CommentTimeSep 14th 2020 edited
    Hi Chris,
    You should give a try to your ..\Contribs\snapshot\ directory. Just a basic contrib I submited to the community a few years ago. Also, have a closest look to the GrabFullScreen() function in Snapshot.prg - imo all you need is there, and many more. :smile:


    Just an excerpt:
    FUNCTION GrabFullScreen(hWndP)
    Local hDcScr, hdcMem, hBmpWin
    Local aScrRect := ARRAY(4)
    Local cBmpFileDest := "Image_"+DTOS(Date())+"_"+nToc(Second())+".bmp"
    NTK_HideWindow(hWndP, .T.)   // temporally hide NTK-Snapshot window
    // Now, we take a snapshot of the full screen...
    hDcScr := NTK_GetDC( NULL )   // Get a DC on the fullscreen
    // Retreive the fullscreen resolution
    aScrRect[ RECT_Left   ] := 0
    aScrRect[ RECT_Top    ] := 0
    aScrRect[ RECT_Right  ] := NTK_GetSystemMetrics( SM_CXSCREEN )
    aScrRect[ RECT_Bottom ] := NTK_GetSystemMetrics( SM_CYSCREEN )
    hDcMem  := NTK_CreateCompatibleDC( hDcScr )
    hBmpWin := NTK_CreateCompatibleBitmap( hDcScr,;
                                           aScrRect[ RECT_Right  ] - aScrRect[ RECT_Left ],;
                                           aScrRect[ RECT_Bottom ] - aScrRect[ RECT_Top  ] )
    NTK_SelectObject( hdcMem, hBmpWin )
    NTK_BitBlt( hDcMem, 0, 0, aScrRect[RECT_Right] - aScrRect[RECT_Left], aScrRect[RECT_Bottom] - aScrRect[RECT_Top],;
                hDcScr, 0, 0,;
                SRCCOPY )
    NTK_DeleteDC( hdcMem )
    NTK_ReleaseDC( hDcScr, NULL )
    NTK_HideWindow(hWndP, .F.)    // Call back the NTK-Snapshot window
    IF NTK_SaveBmp( nil, hBmpWin, cBmpFileDest )
       lRet := .T.
       Alert( "FULL-SCREEN:"+CR+;
              "Picture successfully taken and saved under:"+CR+cBmpFileDest )
       lRet := .F.
        Alert( "FULL-SCREEN:"+CR+;
               "Cannot save "+CR+cBmpFileDest )
    RETURN( lRet )
    • CommentTimeSep 15th 2020 edited

    Hi Ab
    It was there since years and I did not see it! :shamed:
    Many thanks - this is exactly what I was looking for.

    • CommentTimeJan 7th 2021
    Hi gurus,
    Can it work with/from a console window/NTKNOGUI App?
    if so, how?
    • CommentTimeJan 8th 2021
    Hi newbie1
    Of course it can. GrabFullScreen() & GrabWindow() only invoke Win32 APIs. So as long as NTKCORE.Lib is linked to your project - no problems.