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Thread: QPainter performance for zooming and draw...

  1. #1
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    Default QPainter performance for zooming and draw...

    Hi All !!

    I have attached a small example where I drawing a line with mouse movement and zooming the image, but the drawing of the line under the mouse is slow....

    Any idea ?

    Another question....the zoom in this way is correct ?
    "I mean using the transformation matrix"

    Thanks alot ! ...I am sorry for my poor english .
    Attached Files Attached Files

  2. #2
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    Default Re: QPainter performance for zooming and draw...

    You are doing it all wrong. Graphics View is object (item) based whereas you are using it as if it was a regular QWidget. This is where the overhead comes from.

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