Re: performance of goocanvas

[Ed Griffiths <edgrif sanger ac uk>]

I think this is a good guess, we had a lot of trouble with foocanvas (the 
goocanvas predecessor) with this. In the end we were forced to draw certain 
things ourselves on to the screen in order to get good enough performance.

If you are moving the scrolled region as you scroll that would do it....

Ed



> I don't think the problem is drawing. I put a "return;" statement at the
> top of the GooCanvasPolyline's draw function so it didn't draw anything,
> but it was just as slow!
>
> I think the problem may be that you are sometimes changing items when
> the canvas is scrolled, and this causes the canvas to have to
> recalculate the bounds of lots of items, which is slow.
>
> What changes are you making when the canvas is scrolled? Is there a way
> to avoid them?
>
> Damon
>
>
> _______________________________________________
> goocanvas-list mailing list
> goocanvas-list gnome org
> https://mail.gnome.org/mailman/listinfo/goocanvas-list

--
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| Ed Griffiths, Acedb/ZMap development, Informatics Group,               |
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