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Thread: If qt uses double buffer, where are these buffers in case of QGraphicsview ?

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    Default If qt uses double buffer, where are these buffers in case of QGraphicsview ?

    I'm trying to use the already drawed data on Qgraphicsview.
    In case I have to edit one item of 100000 , I think it'd must exist a posibility of having an automatica 'background' buffer copy. But I don find anything related . So I'm going to do myself....

    - Grabwidget are going to redraw all, so it is wasted time.
    - render are going to do the same
    - I'm going to try Grabwindow, but I dont understand how it is impossible (or unknowed by me) to use the actual buffer information...
    Any trick ? Thanks
    Last edited by tonnot; 29th November 2011 at 12:13.

  2. #2
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    Default Re: If qt uses double buffer, where are these buffers in case of QGraphicsview ?

    In the paint event you have QPainter and QStyle. Using these objects you can repaint an object as you like.

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    Default Re: If qt uses double buffer, where are these buffers in case of QGraphicsview ?

    sorry ? I think your answer is not for this question ?

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