A happy new year Frank and Angus,
here my 0.02 Euro, a little late as usual because I moved back to
Germany.
On Wed, Jan 05, 2000 at 05:17:45PM -0500, Frank Warmerdam wrote:
Angus Carr wrote:
> Based on one day's return comments, people on this list see the
> "arcviewization" of GRASS as a good possible thing.
I am not sure describing it as the arcviewization of GRASS is the
best way to develop support for your idea.
I agree with Frank here.
For various reasons, arcview in not the goal I see.
The tale is that a good programmer knows, when to start over again and
put code aside. GRASS is a very useful and rich GIS tool, but I cannot
see how it will ever be a simple mapping and visualisation tool.
Or to put it in another way: To develop a new software package will
need less effort than to extend GRASS to reach the same (GUI) power.
Frank makes a couple of points I agree with.
My personal opinion is that GRASS needs a friendly data viewing environment
more than it needs a friendly interface to the analysis commands. By this
I mean a relatively simple GUI in which you can load various layers of
raster and vector data, browse around, select objects and inspect attributes.
The free software world needs it. 
I can see a few major decisions to make:
o What language to implement it in?
I don't feel the viewer should be implemented in Tcl.
I agree.
My normal bias would be to implement it in C, or now days C++.
Let my throw python in the round. C would work, but C++ is a nasty
language, I saw a couple of free software projects die or suffer,
because of the C++ choice.
As extension languages are scheme (guile) and python state of the art.
o What GUI toolkit to use?
Only a a free cross platform GUI I think.
That eliminates X11, gtk and Qt.
WxWindows, fltk and fox still look good.
(wxWindows runs with native GUI toolskits, like gtk on X11 or MFC on
Windows.)
o How closely is it related to the existing GRASS driver technology?
Does it attempt to maintain some level of compatibility with the
existing GRASS display driver approach?
We'd better say no here.
o How closely does it relate to the existing GRASS data model?
Again, the GRASS model looks a bit like a cage to me to actually
implement an interactive geographic information viewer.
That is why I favour the redesign and reimplementation.
o What sort of commandline interface would be available?
I think Tcl would be
a reasonable choice for an extention language.
Resaonable, maybe, but I see a clear trend towards python and guile or
scheme. (perl still is used, too)
The extension usually is done through exposure of object interfaces.
(Buzzwords: CORBA, COM, SOAP.)
The biggest question is how would such a project be resourced?
Like any free software project, hopefully.
Through a lot of contribution and nice useful code.
Programmers would be paided by different companies to provide solutions.
One final note, I mentioned that I think it should be built on multi-format
vector and raster libraries. This is my area of interest, and I would be
willing to do substantial work to make my raster and vector multi-format read/
write libraries available, and tailoring them to the needs of such a viewer.
True and you already started to work on it.
I am a bit surprised that you did not mention the freegis.org
project.
Our goal certainly is to promote and bundle free software gis/mapping
efforts. We even might start developing such a simple data viewer.
We hope that we can use it in a project and therefore fund developments.
Bernhard
--
Research Assistant, Geog Dept UM-Milwaukee, USA. (www.uwm.edu/~bernhard)
Free Software Projects and Consulting (intevation.net)
Association for a Free Informational Infrastructure (ffii.org)