[QGIS-trac] Re: [Quantum GIS] #1875: A few problems with crs definitions with TOWGS parameters

[Quantum GIS]

#1875: A few problems with crs definitions with TOWGS parameters
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        Reporter:  lutra                                      |         Owner:  homann       
            Type:  bug                                        |        Status:  closed       
        Priority:  critical: causes crash or data corruption  |     Milestone:  Version 1.2.0
       Component:  Projection Support                         |       Version:  HEAD         
      Resolution:  fixed                                      |      Keywords:               
Platform_version:                                             |      Platform:  All          
        Must_fix:  No                                         |   Status_info:  0            
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Comment (by neteler):

 Replying to [comment:25 lutra]:
 ...
 > When loading the layer defined with B) qgis strips or ignores
 >
 > "+towgs84=-104.1,-49.1,-9.9,0.971,-2.917,0.714,-11.68"
 >
 > and shows just
 >
 > "+proj=tmerc +lat_0=0 +lon_0=9 +k=0.9996 +x_0=1500000 +y_0=0
 +ellps=WGS84 +datum=WGS84 +units=m +no_defs"
 >

 So effectively you shift/rotate/scale the map at this point into the wrong
 direction. If QGIS ignores +towgs84, please don't say "fixed" here because
 it isn't. I'll make more tests.

 In GRASS, we have a dialog which pops up for the definition of the datum
 and the user can select the datum. And it is not ignored...

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/1875#comment:26>
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