[cairo] Re: Newbie asks questions

[Jeff Kowalczyk]

Okezsoke wrote:
> My thesis' theme is asset tracking, so I have to write a program
> displaying map from a database. My friend write the database structure
> and my task is the displaying. Actually I do not know much about this.
> We choosed Kylix 3 to develop the program. While I was searching on the
> Net, I found Cairo.

Normally on Windows (Delphi == Kylix) you buy a commercial control to do
the rendering of maps. It's non-trivial amount of coding to make the map
display interactive, and possibly too much work for a thesis.

If I had this task and a limited time, I'd make the platform a web
application, and reuse an existing program like Mapserver to do the
rendering. Also see PostGIS, ZMapserver and PloneMap.

http://mapserver.gis.umn.edu/
http://zmapserver.sourceforge.net/
http://postgis.org/
http://plonemap.makina-corpus.org/map

Python is a very good language for your tasks and timeframe, if you don't
have any particular attachment to Kylix.

If you need to write everything from scratch for academic reasons, I would
suggest you write the program to draw your maps in SVG from your
colleague's data. Cairo can help you output these as PNG for display to
the web browser, if you can't use a Mozilla compiled with SVG support by
the time you finish.

Here's an article that could give you the idea: See the "The Finishing
Touches" section:
http://msdn.microsoft.com/msdnmag/issues/0300/sql/default.aspx
Substiture SVG for the obsolete VML, and use python scripting against
postgresql and postgis, instead of the XML features of MS-SQL server.
The Cairo developers tell us we can optionally use Cairo to render that
SVG to PNG on demand now.