On Fri, Oct 27, 2006 at 06:30:53AM -0700, we recorded a bogon-computron collision of the <[EMAIL PROTECTED]> flavor, containing: > On Thu, 26 Oct 2006, Dick C. Reichenbach wrote: > > > How does rtree indexing affect redrawing of weather alerts? Weather > > alert redrawing is one of the major drags on my machine. I've been > > using rtree indexing for a very long time now, but I've never seen a > > difference, as far as weather alerts go. > > It should speed things up a bit for the 2nd draw out of a file and > succeeding draws.
Not really. > One thing that could really speed up weather alerts would be > changing the code to go through each file once looking for all the > alerts from it. Right now we run through the file once for each > shape, which isn't efficient. This is why. Rtree reduces the time spent rendering a shapefile by speeding up the selection of on-screen elements. WIthout rtree, xastir does a linear search through the entire shapefile, checking each shape's bbox against the screen. With rtree, xastir does a query against the index that amounts to "select all shapes on screen". Since weather alerts are done by calling draw_shapefile_map once for each alert, and the alert's shape is stored as an index into the shapefile, rtree actually has nothing to do. Rtree should have no impact at all on wx alert drawing. -- Tom Russo KM5VY SAR502 DM64ux http://www.swcp.com/~russo/ Tijeras, NM QRPL#1592 K2#398 SOC#236 AHTB#1 http://kevan.org/brain.cgi?DDTNM "And, isn't sanity really just a one-trick pony anyway? I mean all you get is one trick, rational thinking, but when you're good and crazy, oooh, oooh, oooh, the sky is the limit!" --- The Tick _______________________________________________ Xastir mailing list [email protected] http://lists.xastir.org/cgi-bin/mailman/listinfo/xastir
