[Freegis-list] Re: Geo::Shapelib

[Ari Jolma]

Emad Fanous wrote:

>Ari,
>
>Thanks for creating your module.  I just have 1 suggestion:
>It slurps everything into memory (push the shape records onto
>$self->{Shapes}) which, as you can imagine, isn't a good thing for a large
>file.  Perhaps handling this another way would be better.
>  
>

In fact there is a LoadAll (default is true) parameter for the 
constructor, which, if set to false, prevents this slurping.

I have not played with that feature a lot (can't even remember if it was 
my idea to put it there), maybe I have fast machines with lots of memory 
or my shapefiles are small (perhaps not really, currently I play with 
shapefiles of size ~25 MB) but I haven't had the need.

In the latest version I added R-trees (Perl-only solution, using 
Tree::R, which I made up) but they are too slow for files with many 
(>1000) shapes, so I started looking at the indexing in the C-code, 
which would mean not loading the data into Perl structures.

I haven't also been using Geo::Shapelib much myself until very recently. 
I made a GUI with Perl Gtk2 modules (called Gtk2::Ex::Geo and to be 
released soon -- there is a preliminary version with different name in 
libral.sf.net) which can load and show Geo::Raster and Geo::Shapelib 
objects and that has got me interested in Geo::Shapelib again.

One more thing. We need an email list for discussing Perl Geo::  and 
Geography:: modules (there is already a good selection of those). I hope 
you don't mind if I cc this to the freegis-list, which is the best 
existing list for this purpose I know, but not Perl-specific. Anybody 
have any ideas? Are there any Perl geeks on this list?

Cheers,

Ari

>Thanks
>Emad
>  
>