[GRASS-dev] [grass-code I][544] Map Display crashes when zooming (too much) in!

[Maris Nartiss]

Hi Michael and others.

To reproduce this problem more easily than with Spearfish dataset just
create new location with parameters like in initial bug report.
For some reason at some point variables $mapwd or $mapht get values
like "1.8912764e-10" or similar and then are not catched by $mapwd==0
comparison. I attached small quick hack around problem that limits
zoom-in to half of cell size (resolution). It fixes this problem but
may cause problems for users without sane resolution like after
creating new location from vector data source. Still requiring sane
resolution for location is not worse case scenario. Or should we limit
zoom-in till mapwd is smaller than 2?


Maris.

2007/11/29, Michael Barton <michael.barton at asu.edu>:
> I just tried this with cvs compiled from an update of this morning and had
> no problems.
>
> In normal mode, if you zoom to less than 1 raster cell, a TclTk message box
> pops up saying you've exceeded the maximum zoom.
>
> In explore mode, you can zoom to much less than 1 raster cell.
>
> In neither case did I get a TclTk error like the one below.
>
> I did wait until a map  was completely displayed before trying to zoom
> again.
>
> I tried this on a Mac PPC G5, with OS X 10.4.11.
>
> Has anyone else had this problem?
>
> Michael
>
>
> On 11/28/07 5:01 PM, "grass-dev at lists.osgeo.org" <grass-dev at lists.osgeo.org>
> wrote:
>
> > code I item #544, was opened at 2007-11-29 00:01
> > Status: Open
> > Priority: 3
> > Submitted By: Nikos Alexandris (nikosa)
> > Assigned to: Nobody (None)
> > Summary: Map Display crashes when zooming (too much) in!
> > Issue type: other bug
> > Issue status: None
> > GRASS version: CVS HEAD
> > GRASS component: display
> > Operating system: Linux
> > Operating system version: Ubuntu 7.10
> > GRASS CVS checkout date, if applies (YYMMDD):
> >
> >
> > Initial Comment:
> > .The Display Crashes when zooming in too much in a specific point (in a raster
> > map) displayed in Map Display.
> >
> > .First error message is: Error setting region: child process exited abnormally
> >
> > .Second error message (after pressing ok): Error: can't read
> > "parts(projection)"...
> >
> > can't read "parts(projection)": no such variable
> > can't read "parts(projection)": no such variable
> >     while executing
> > "regexp -nocase {^.* (\(.*\))} $parts(projection) trash end"
> >     (procedure "MapCanvas::runprograms" line 46)
> >     invoked from within
> > "MapCanvas::runprograms $mon [expr {$mymodified != 0}]"
> >     (procedure "MapCanvas::drawmap" line 38)
> >     invoked from within
> > "MapCanvas::drawmap $mon"
> >     (procedure "MapCanvas::display_server" line 9)
> >     invoked from within
> > "MapCanvas::display_server"
> >     ("after" script)
> > ---
> >
> > .Don't know if g.region -p is necessary to report... (just for any case):
> >
> > GRASS 6.3.cvs (Peloponnese_HGRS87):~/> g.region -p
> > projection: 99 (Transverse Mercator)
> > zone:       0
> > datum:      towgs84=-199.87,74.79,246.62
> > ellipsoid:  grs80
> > north:      4255230
> > south:      3994272
> > west:       226090
> > east:       468372
> > nsres:      249.95977011
> > ewres:      250.03302374
> > rows:       1044
> > cols:       969
> > cells:      1011636
> > [Raster MASK present]
> >
> >
> >
> > ----------------------------------------------------------------------
> >
> > You can respond by visiting:
> > http://wald.intevation.org/tracker/?func=detail&atid=204&aid=544&group_id=21
> >
>
> __________________________________________
> Michael Barton, Professor of Anthropology
> Director of Graduate Studies
> 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
>
> _______________________________________________
> grass-dev mailing list
> grass-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/grass-dev
>