[Freegis-list] Geovisualization / mapping library

[Mateusz Loskot]

Ari Jolma wrote:
> Mateusz Loskot kirjoitti:
>> Ari Jolma wrote:
>>> This project is related to the OSGeo Cartographic Library proposal: 
>>> http://wiki.osgeo.org/wiki/OSGeo_Cartographic_Library
>>
>> It's very interesting though the general idea is a bit vague to me.
>> I've read the Wiki page and I'm still unable to grab the core of this 
>> idea. So, if you don't mind, I'd like to ask some questions:
>>
>> 1. Is this idea about creating something like libgd (http://libgd.org) 
>> for GIS - not another geometry rendering engine, but a renderer 
>> specialized for GIS and cartpgraphy?
> 
> Basically yes.

OK

>> 2. What are the key differences to MapServer and Mapnik?
> 
> There aren't really so many. The technology is one (Cairo instead of 
> AGG) and the idea to limit the scope to just the rendering but at the 
> same time trying to be more flexible towards explorative visualization 
> etc. But I really can't tell, I'm not intimate with either of those and 
> every time I look they have evolved.

I understand.

> I plan to use GDAL as the only data source but I anticipate use cases 
> which require stretching the GDAL data model a bit. For example layers 
> of features with differing schemas and possibly multiple geometries.

GDAL use is an advantage for me :-)

>> 3. Why GNOME libraries but not something multiplatofrm in terms of 
>> desktop environments?
> 
> Personal choice ;) -- interoperates well with the other stuff I do. GTK 
> (the foundation of GNOME) is multiplatform.

OK

> What do you mean by "something multiplatform"?

I mean not multiplatofrm across operating systems but desktop 
environments. There is some feeling like Gtk targets GNOME (or Xfce), Qt 
targets KDE. Certainly, Gtk works under KDE and Qt under GNOME, but 
there is a lot of layers specific to each of these environments.
Anyway, I was just curious and the "personal choice" answers
my question :-)

>> 4. How does it relate to FOSS desktop applications like QGIS? Is the 
>> library going to serve as desktop GIS core in future (like desktop GIS 
>> for GNOME)?
> 
> QGIS uses Qt, which is similar in functionality to GTK but different. 

Yes

> I'm surely going to use the library as a building block for a GTK 
> "geocanvas" and then use the geocanvas as a building block for geo 
> applications. I'll probably use Perl for most of the canvas and the 
> apps. This will (hopefully) replace some graphics code I have now in 
> libral.

Understood.

> It would be interesting if this library could evolve into something more 
> broadly used by the GTK/GNOME community.

Yes, as a fan of GNOME environment, I also thikn that would be nice.

Thanks Ari for comments. For now, I'll only monitor the project.

Greetings
-- 
Mateusz Loskot
http://mateusz.loskot.net