[GRASS-dev] New installation for wxPython GUI

[Michael Barton]

Classes start soon and it's getting busy here.

A lot of good ideas floating around with the possibility of a Python
interface. I'll try to give my 2cents worth on several in order.

Glynn should be almost done with his redo of the raster library that will
let us send any d.* command to a PNG/PPM file without having to run d.mon.
This will be a significant change to the coding and a big improvement. Given
that wxPython will accept graphic streams (one of it's big improvements over
TclTk) I wonder if we should think about giving all the d.* commands the
option outputting to a graphic stream (stdout??? Or some other pipe???) as
well.

For vectors, however, it seems like the best thing would be if d.vect could
also output in a dxf-like format, that included a set of formatting strings
(line width, color, etc) and label text, followed by a specifier of vector
type (point, line, area) and cat number, and finally followed by a set of xy
coordinate pairs for each  vector object. This could then be picked up by a
GUI to draw to screen rather than import as a raster image. You shouldn't
have to worry about the vector database attributes because Trevor's v.what
will find those simply by sending xy coordinates to the underlying vector
file. Could something like this help with the digitizing? One thing about
wxPython that concerns me in this respect (and something that was NOT a
problem with TclTk) is that it doesn't seem to treat drawings to a device
context as a vector object, but as  a raster. This is why I'm having trouble
with the ugly zoom boxes. It's not easy to erase the box as its drawn
without erasing the whole screen. Again, this  may be because I just don't
know enough.

Many of the screen decorations (legend, scale, grid, etc.) currently done by
d.*  commands should be done by the GUI probably. Or better yet, the d.*
commands should again output text equivalents of what they are drawing that
can be picked up by the GUI and drawn. For example, d.legend should output
information about box size, colors of each legend object, text format, etc.

One thought that just came to me is that perhaps d.* commands should  also
output what they do in ps.map format. This could either be run through
ps.map or sent to a GUI.

Michael
__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton



> From: Jachym Cepicky <jachym.cepicky at centrum.cz>
> Date: Thu, 10 Aug 2006 19:15:38 +0200
> To: Moritz Lennert <mlennert at club.worldonline.be>
> Cc: Michael Barton <michael.barton at asu.edu>, Grass Developers List
> <grass-dev at grass.itc.it>, Trevor Wiens <twiens at interbaun.com>, David Finlayson
> <david.p.finlayson at gmail.com>, Yann Chemin <ychemin at gmail.com>
> Subject: Re: [GRASS-dev] New installation for wxPython GUI
> 
> hi
> On Thu, Aug 10, 2006 at 05:36:56PM +0200, Moritz Lennert wrote:
>> A completely different question: Michael, are you planning on continuing
>> with the raster drawing system via the ppm files, or should the wxpython
>>  manager actually display vector drawings when displaying vector maps ?
>> 
>> Moritz
> 
> how would you do it?
> 
> jachym
> -- 
> Jachym Cepicky
> e-mail: jachym.cepicky at centrum.cz
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