[GRASS-dev] updates to region setting and display rendering in GIS Manager

[Michael Barton]

I just committed a set of updates to the cvs that should enhance region
management and display rendering times in the GIS Manager.

The display no longer uses d.mon and the PNG driver to create graphic output
to render to the TclTk canvas (i.e., map display). Instead, it uses the new
GRASS_RENDER_IMMEDIATE mode that is one of the new results of Glynn
Clement's revamping of the underlying GRASS display code. One informal test
suggested that this might as much as half rendering times, but I can't
confirm this. However, it does simplify display management and should reduce
potential conflicts with older display tools using d.mon and x11 displays.

Region setting also now uses one of Glynn's new tools, the GRASS_REGION
setting. What this means is that GRASS's complicated, but useful, region
geometry management should be a little easier and a lot more consistent from
the GIS Manager. Specifically:

-Each display maintains its own geometry/region settings, which do not
affect
anything else.

-Changing the zoom (region settings) in a display will have no automatic
effects on the computational region/geometry for any GRASS command run from
the menu or command line.

-Setting the region with g.region will affect the computational
region/geometry of any GRASS command run from the menu or command line in
the same way, no matter how g.region is started. It will have no automatic
effects on any display.

-Except for the display in the TclTk canvases of the GIS Manager, all GRASS
commands will use the same region information, whether started from the
command line or menu.

-You can explicitly set the region for non-display commands to match the
display region, but only if you choose to do so.

-You can explicitly set the display to match the WIND region set with
g.region, but only if you choose to do so.

I've also added a display of some region information at the bottom of each
display to help users know what they're looking at.

Hopefully, this will make the whole geometry setting process easier and more
consistent across all the program.

I also added both the new display rendering and region management to the
georectifier.

Finally, I was able to fix a nasty bug that locked up gism if there was a
bad raster name in the layer tree. Now it will report the problem in the
grass console, but otherwise ignore it.

Please test these updates. If they hold up, they should be backported to 6.2

Thanks to those who have done previous testing and helped me sort out these
issues.

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

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