crash if zooming in too much

[msieczka]

r32363

1. Add a raster map (raster or vector).

2. Zoom in until an error like this pops up:

Execution failed: 'd.rast map=N51E016@PERMANENT --q'

Details: 
 ERROR: region for current mapset line 1run "g.region"

3. Try to "Zoom to selected map" or any other zoom operation - a crash:

 Traceback (most recent call last):
  File "/usr/local/grass-6.4.svn/etc/wxpython/gui_modules/ma
pdisp.py", line 2076, in OnZoomToMap

self.ZoomToMap()
  File "/usr/local/grass-6.4.svn/etc/wxpython/gui_modules/ma
pdisp.py", line 2129, in ZoomToMap

self.UpdateMap()
  File "/usr/local/grass-6.4.svn/etc/wxpython/gui_modules/ma
pdisp.py", line 579, in UpdateMap

self.mapfile = self.Map.Render(force=True,
mapWindow=self.parent, windres=windres)
  File "/usr/local/grass-6.4.svn/etc/wxpython/gui_modules/re
nder.py", line 762, in Render

if not layer.Render():
  File "/usr/local/grass-6.4.svn/etc/wxpython/gui_modules/re
nder.py", line 135, in Render

os.environ["GRASS_PNGFILE"] = self.mapfile
  File "/usr/lib/python2.5/os.py", line 474, in __setitem__

putenv(key, item)
TypeError
:
putenv() argument 2 must be string, not None

[msieczka]

Michael Barton commented on GRASS dev ML:

Arrgh. Fixed this in TclTk but seems like we need to fix it in wxPython too. Thanks for spotting it. With new graphic tools in wxpython, Glynn's rewrite of the display drivers, and Martin's work on nD visualization we may be reworking the display rendering engine. At the moment, I'm not sure how much will be back ported to wxpython. We might try a simple patch on this for the moment, however. I'll try to look into it.

[cmbarton]

I just tested this on current 6.4 svn. I zoomed until I got an error similar to the one above, with the added explanation that the zoomed region was smaller than the region resolution. In fact it was a LOT smaller than the region resolution by the time I hit this error.

But the error simply raised an error message and did not cause a crash. I zoomed to selected map and it worked fine.

I think this has been fixed in the year since this was last reported. If this causes a crash on someone else's system, we can reopen it.

Michael