[OSGeo-Discuss] Proposal: OSGeo Cartographic Library

[Sampson, David]

Hey folks,

Lots of good discussion going on around this proposed library.

>From the sounds of it there are many different camps of thinking on this
subject which is great. Of course there are many approaches that can be
used.

Perhaps we might want to talk a little more about the high end user
needs and work backwards. For instance if the end user does not want
PDF's or has other requirements then symatical debate on the best PDF
engine may not be required right now.

There is an "end User Needs" section
http://wiki.osgeo.org/wiki/OSGeo_Cartographic_Library#End_User_Needs
where PDF is only one required output.


For starters I think bringing the FOSS4G world into the world of
"cartographic product" production would be a huge jump. Whether is be
digital-digital or digital-paper. Being able to do this using many
applications and some custom API I think would keep flexibility open. So
if many libraries can be included, lets include them. We'll all have
different user requirements.

Of course staying standards based where possible would be ideal so using
context documents or SLD or something simmilar as an optional output
would increase up take.

As a final user product I would love to see something that ties easy
drag/drop, point and click interactive design interface with real time
screen refresh that could produce something akin to a Generic Maptool
Tools (http://gmt.soest.hawaii.edu/) script to produce a preview before
I print it. Of course having options to use java and python to script
workflows would suite the needs of power users who balk at GUI's. 

I know that the seprate projects will be responsible for the GUI. If we
work backwards from the functionality of the GUI though I think we can
find the pieces we need. Infact producing a full cartographic map layout
in SCRIBUS  or using it's technology might be the best way to not
reinvent the wheel for the end user.

Has anyone thught out the Pseudo code for the process? Posted on wiki
http://wiki.osgeo.org/wiki/OSGeo_Cartographic_Library#Worflow

* read geo data
	* geometries
	* projection
	* metadata (if required)
* apply styling
	* feature to style coding
* Cartographic edits
	* overide some of the geometry if required (eg roads don't run
through lakes)
* manual edits / retouching
* Produce  other cartographic edits objects
	* create suround
	* create grids
	* create legend
	* create scale bar
	* create north arrow
	* Copyright notices from text file or DB
	* Licensing notices from text fiel or DB
* Other
	* Output size


La la la 

I'll post this to the wiki, maybe flushing this step out will allow us
to match a library(ies) to a task(s).




Hopefully we don't get hung up too much on choosing a narrow selection
of libraries and keep the carto library itself quite open and flexible.

Just some thoughts.