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Re: [udig-devel] Rendered features
I implement selection tool and to have better performance I cached features rendered on map ( because only this can be selected by user) . This functionality is also used with snapping it is faster to filter on features in cache than looking into database especially when multilayer snapping is on.

Peter

W dniu 2013-02-08 03:39, Jody Garnett pisze:
Can I ask what you are trying to accomplish with a list of features already on the map? Perhaps there is another way to accomplish what you are after?

-- 
Jody Garnett

On Thursday, 7 February 2013 at 8:06 PM, Piotr Zduńczyk wrote:

Thanks for Your replay.
It sheds some light on reasons why it is done in such a way.

Peter

W dniu 2013-02-06 23:36, Jody Garnett pisze:
We do not as a rule cache any features - in part so we can work with massive content.

As a framework we want to be as light on resources as possible, and leave it up to applications that use uDig to choose when (and what) to cache.

There is a cache checkbox in the style editor you can tick as an experimental option, it keeps the features in a spatial index (and pull features in as needed as your scroll around. It is very effective when working with things like WFS.

The second question is a bit more interesting, wanting features in world coordinates.

If you want to do that make a request of the feature source and fill in the viewport CRS in the Query object. The features will be reprojected as they come out of the database or shapefile. Indeed in some cases the data sources supports native reproduction allowing us to do less work in uDig.

Note that the features that are drawn on screen are subject to "decimation" by the rendering engine, we throw out coordinates on the fly, based on the math transform constructed between the original data, the world CRS and the affine transformation to the screen. The earlier we can throw out coordinates the less information involved in drawing, and the faster we can update the screen.

Jody




On Wed, Feb 6, 2013 at 10:33 PM, Piotr Zduńczyk <zdu@xxxxxxxxxx> wrote:
Hi,

Is any possibility in uDig to get all features rendered on map?
Is there any cache or something like that?
I was previously collect features in BasicFeatureRenderer by caching features in BasicRenderListener but from uDig 1.3 features have coordinates recalculated from work to pixel, and I want features with word coordinates..
Any ideas how to do that?

Thanks,
Peter

_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel




_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel


--
Piotr Zduńczyk
Inżynier Oprogramowania

Globema Sp. z o.o.
ul. Wita Stwosza 22
02-661 Warszawa
tel. (+48) 22 848 73 13 wew. 313
fax (+48) 22 848 68 83
www.globema.com/pl/


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_______________________________________________
User-friendly Desktop Internet GIS (uDig)
 



_______________________________________________
User-friendly Desktop Internet GIS (uDig)
http://udig.refractions.net
http://lists.refractions.net/mailman/listinfo/udig-devel


--
Piotr Zduńczyk
Inżynier Oprogramowania

Globema Sp. z o.o.
ul. Wita Stwosza 22
02-661 Warszawa
tel. (+48) 22 848 73 13 wew. 313
fax (+48) 22 848 68 83
www.globema.com/pl/


"Treść tej wiadomości może zawierać prawnie chronione informacje poufne. Jeśli otrzymaliście ją Państwo przez pomyłkę, prosimy o niezwłoczne powiadomienie o tym nadawcy oraz jej usunięcie z Państwa komputera, bez wykonywania dystrybuowania lub zatrzymywania jakiejkolwiek jej kopii.

This message may contain confidential information protected by law. If you have received this message by mistake, please immediately inform the sender of the mistake and delete this message from your system without making, distributing or retaining any copies of it."

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