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Thread: draw ellipse with specific points in scene

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    Default draw ellipse with specific points in scene

    hi friends,Experts,
    i want to know how i can draw ellipse with the three points marked in the qgraphicsscene . say if the user selects three points in the scene using mousePress i will highlight the pressed points with marks . now using the the three marks i have to draw an ellipse around the three marks or making the points as a boundary for the ellipse i draw .circlemark.png . please help me . suggest me the way i can implement .
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    Default Re: draw ellipse with specific points in scene

    i want to know how i can draw ellipse with the three points marked in the qgraphicsscene
    It better be a circle (there will be infinitely many ellipses that pass through those points).

    Read more about Circumscribed circle, all the required math is mentioned there. All you need to do is calculate the circle centre and radius, and use Qt API void drawEllipse(const QPoint & center, int rx, int ry);
    When you know how to do it then you may do it wrong.
    When you don't know how to do it then it is not that you may do it wrong but you may not do it right.

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