[QGIS-trac] Re: [Quantum GIS] #1176: Transverse mercator south orientated projections not supported

[Quantum GIS]

#1176: Transverse mercator south orientated projections not supported
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        Reporter:  halfhaggis                       |         Owner:  nobody       
            Type:  bug                              |        Status:  reopened     
        Priority:  minor: annoyance or enhancement  |     Milestone:  Version 1.0.1
       Component:  Projection Support               |       Version:  HEAD         
      Resolution:                                   |      Keywords:               
Platform_version:                                   |      Platform:  Debian       
        Must_fix:  No                               |   Status_info:  0            
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Comment (by halfhaggis):

 I've been communicating with Gerald Evenden who has a lot to do with the
 proj4 library.

 Via command-line, I can get the correct projections with this sample input
 (filename proj2):
 26.67029 -30.69927

 where first column is longitude and second column latitude

 and this command and output
 $ proj +proj=tmerc +ellps=WGS84 +lon_0=27 -m -1 proj2
 31587.18        3397679.73

 The -m flag doesn't work when defining a custom projection in qgis. Is
 there some other way to get the -m behaviour when defining custom
 projections?

 From the proj man file:

  -m mult
               The  cartesian  data may be scaled by the
               mult parameter.  When processing data  in
               a  forward  projection mode the cartesian
               output values are multiplied by mult oth‐
               erwise  the  input  cartesian  values are
               divided by mult  before  inverse  projec‐
               tion.   If  the  first  two characters of
               mult are 1/ or  1:  then  the  reciprocal
               value of mult is employed.

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/1176#comment:4>
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