Makes sense to me. The selection handler design is one thing that really doesn't scale all that well. It's a tough problem - how do you keep track of an arbitrary set of things without actually keeping references to them?
Actually, this problem was the motivation behind my developing the Geometry Function tool. When I need to extract a big set of things determined by a spatial Area-Of-Interest, I just create a new layer with the AOI shape, and then use Geometry Function with the intersects predicate to extract the desired features to a new layer. I think this is exactly what you're proposing with your Copy Fenced Features to New Layer plugin, right? Seems like a good thing to have this available a bit more directly. The advantage to using Geometry Function/intersects is that it's easy to use an existing feature geometry as the Mask. At one point I was thinking it would be nice to have a Set Fence from Geometry menu item as well. Larry Becker wrote: > Hi, > > Recent work with Extract Layers by Geometry Type, and improving > OpenJump's support for very large selections, has convinced me that > JUMP needs a mechanism for dealing with subsets of large layers. > Although the selection mechanism is very flexible, it is very > expensive in terms of memory and processing. To seem what I mean, > consider Arnd's million point layer problem. To break the layer into > more manageable pieces, he tried to select some of the points and move > them to another layer. When this is done with such a large selection, > the UI must build gigantic data structures. The result is an > extremely slow response or an out of memory error. > > An approach that might work for some problems is to use the Fence tool > to indicate a subset of the data that can be used in place of a > selection. The advantage is that no data structures are needed and > there are no selection handles to draw. I was thinking of producing > another Layer Extract plugin that would extract features in the Fence > to a new layer. By coding support methods in a utility class, we > could gradually add support for "features in fence" subsets to the > other tools. > > What do you think? > > regards, > > Larry Becker > > -- > http://amusingprogrammer.blogspot.com/ > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > ------------------------------------------------------------------------ > > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > -- Martin Davis Senior Technical Architect Refractions Research, Inc. (250) 383-3022 ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
