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Thread: rendering svg using QGraphicsSVGItem slows doen the performance

  1. #1
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    Default rendering svg using QGraphicsSVGItem slows doen the performance

    Hi,

    I have created application using graphicaview architecture. I can create several different items on the view.
    Items can be movable, focusable. But when i create svg item by using QGraphicsSvgItem, performance of the application slows down.
    This happens specially with the large svg files.

    Any idea how to imrove the performance.

    regards,
    ~Sanjay

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    Default Re: rendering svg using QGraphicsSVGItem slows doen the performance

    Yes - don't use SVG files.
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  3. #3
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    Default Re: rendering svg using QGraphicsSVGItem slows doen the performance

    Thanks.

    But we also need to scale the items. So if we use the images like .png, that will be at the cost of quality.

    where as scaling the svg preserve the quality of the image.

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    Default Re: rendering svg using QGraphicsSVGItem slows doen the performance

    Well... you can't have both speed and agility, unfortunately. The only thing you can do is to enable caching for your svg items. Use QGraphicsItem::DeviceCoordinateCache.
    Last edited by wysota; 1st September 2009 at 08:02.
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  5. #5
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    Default Re: rendering svg using QGraphicsSVGItem slows doen the performance

    If you have a videocard; use a QGLWidget as viewport in you're GraphicsView (setViewport()) and not a normal QWidget.

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