[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
--------------------------------------------------------------+-------------
        Reporter:  lutra                                      |         Owner:  homann       
            Type:  bug                                        |        Status:  reopened     
        Priority:  critical: causes crash or data corruption  |     Milestone:  Version 1.2.0
       Component:  Projection Support                         |       Version:  HEAD         
      Resolution:                                             |      Keywords:               
Platform_version:                                             |      Platform:  All          
        Must_fix:  No                                         |   Status_info:  0            
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Comment (by homann):

 It appears to be an intended change in PROJ.4, see this comment from
 pj_transform.c:'

 ---
 /* -------------------------------------------------------------------- */
 /*      We cannot do any meaningful datum transformation if either      */
 /*      the source or destination are of an unknown datum type          */
 /*      (ie. only a +ellps declaration, no +datum).  This is new        */
 /*      behavior for PROJ 4.6.0.                                        */
 /* -------------------------------------------------------------------- */
 ---

 As there is no datum specified in the +proj string, +towgs84 has no
 effect. With an old libproj 4.4.9, it seems to work.

-- 
Ticket URL: <https://trac.osgeo.org/qgis/ticket/1875#comment:16>
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