[QGIS-trac] Re: [Quantum GIS] #1159: Identify tool with on-the-fly projection can crash

[Quantum GIS]

#1159: Identify tool with on-the-fly projection can crash
--------------------------------------------------------------+-------------
        Reporter:  barryrowlingson                            |         Owner:  telwertowski 
            Type:  bug                                        |        Status:  new          
        Priority:  critical: causes crash or data corruption  |     Milestone:  Version 1.0.0
       Component:  Projection Support                         |       Version:  HEAD         
      Resolution:                                             |      Keywords:               
Platform_version:  Windows 0.10.0-Io (8383)                   |      Platform:  All          
        Must_fix:  No                                         |   Status_info:  0            
--------------------------------------------------------------+-------------
Changes (by telwertowski):

  * owner:  nobody => telwertowski
  * platform:  Debian => All

Comment:

 Happens on Mac too (and most likely all platforms):

 {{{
 Debug:
 /Users/tce/developer/qgis/trunk/src/core/qgscoordinatetransform.cpp: 498:
 (transformCoords) Projection failed emitting invalid transform signal:
 Failed inverse transform of
 (-5.84894e+08, 6.4696e+08)
 with error: tolerance condition error

 Warning: Throwing exception
 /Users/tce/developer/qgis/trunk/src/core/qgscoordinatetransform.cpp502
 Warning: Throwing exception
 /Users/tce/developer/qgis/trunk/src/core/qgscoordinatetransform.cpp272
 Debug: Transform error caught in
 /Users/tce/developer/qgis/trunk/src/core/qgsmaprenderer.cpp line 630:
 Failed inverse transform of
 (-5.84894e+08, 6.4696e+08)
 with error: tolerance condition error

 terminate called after throwing an instance of 'QgsCsException'
   what():  Failed inverse transform of
 (-5.84894e+08, 6.4696e+08)
 with error: tolerance condition error

 Abort trap
 }}}

 There are two things to fix here.

 1) QGIS needs an exception handler on the main event loop so that an
 exception alert is displayed and the user is allowed to continue without
 crashing.

 2) The Identify code ought to handle this specific exception and report
 "No features found" much as it does if you click above or below the poles
 using an unprojected map.

-- 
Ticket URL: <https://trac.osgeo.org/qgis/ticket/1159#comment:1>
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