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QGraphicScene

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  • G Offline
    G Offline
    grsabourin
    wrote on last edited by
    #1

    Hi

    I use a QGraphicScene to display a grayscale image. On this grayscale image I draw an overlay that is a rectangle.

    I do it in this way.

    QGraphicsScene m_scene;
    QPixmap imTmp = QPixmap::fromImage(m_displayImage); // m_displayImage is a QImage
    m_displayImagePtr = m_scene.addPixmap(imTmp);
    m_externalOverlayImagePtr = m_scene.addPixmap(overlayIm); //overlayIm is a QPixmap containing only the rectangle

    Many time the rectangle is not displayed completely. One or two sides are missing. If I play with the size of my window I'm able to get a size where I have entire rectangle. I have a window resize function that permit to resize the image to keep it maximized in the display and keeping the aspect ratio. I have played with setZValue of the rectangle item without success.

    Thank you

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    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #2

      Hi,

      Shouldn't you breathe use QGraphicsScene::fitInView ?

      Interested in AI ? www.idiap.ch
      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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