Re: events on a lot of triangles: [simplification of a previous post]



The problem with any general canvas solution is that it can only make limited assumptions about the scale and subdivision of the data. E.g. if you know that all your line segments are of certain max size, then you can use that knowledge to do a more efficient lookup. Look e.g. at Google Earth that is presenting different info depending on the zoom-in. I assume that it is achieving that through a heavy preprocessing of the data that is cached on the server. This is difficult to do with a general purpose canvas object. That's why I turned to a callback model in my widget gtk_image_viewer , that is much more flexble, though you have to do more work on your own.

Regards,
Dov


2009/2/9 Murray Cumming <murrayc murrayc com>
On Sat, 2009-02-07 at 02:08 +0100, Fabio Mariotti wrote:
>
> Is there any alternative to gnome-canvas?
> In particular gnome-canvas was working nicely up to 20000 objects
> but a bit heavy with 40000. (I would guess that an equivalent
> canvas solution will suffer the same problem..)

goocanvas is quite popular and they seem to have some emphasis on
performance. You should definitely try it.

--
murrayc murrayc com
www.murrayc.com
www.openismus.com

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