<div>Sorry to bring this up again. I&#39;ve been looking for why epsg_tr.py -proj4 is not including the +gamma (RectifiedToSkew angle) parameter for the +proj=omerc projection as used in EPSG:3168, EPSG:3375, etc. It seems that it is not set in <a href="https://svn.osgeo.org/fdo/trunk/Thirdparty/gdal/ogr/ogr_srs_proj4.cpp">https://svn.osgeo.org/fdo/trunk/Thirdparty/gdal/ogr/ogr_srs_proj4.cpp</a>:</div>

<div><span class="Apple-style-span" style="font-family: monospace; white-space: pre-wrap; font-size: medium; "><br></span></div><div><span class="Apple-style-span" style="font-family: monospace; white-space: pre-wrap; font-size: medium; ">else if( EQUAL(pszProj,&quot;omerc&quot;) )</span></div>

<div><span class="Apple-style-span" style="font-family: &#39;Times New Roman&#39;; font-size: medium; "><pre style="word-wrap: break-word; white-space: pre-wrap; ">    {
        SetHOM( OSR_GDV( papszNV, &quot;lat_0&quot;, 0.0 ), 
                OSR_GDV( papszNV, &quot;lonc&quot;, 0.0 ), 
                OSR_GDV( papszNV, &quot;alpha&quot;, 0.0 ), 
                0.0, /* ??? */
                OSR_GDV( papszNV, &quot;k&quot;, 1.0 ), 
                OSR_GDV( papszNV, &quot;x_0&quot;, 0.0 ), 
                OSR_GDV( papszNV, &quot;y_0&quot;, 0.0 ) );
    }</pre><pre style="word-wrap: break-word; white-space: pre-wrap; ">...</pre></span><span class="Apple-style-span" style="font-family: &#39;Times New Roman&#39;; font-size: medium; "><pre style="word-wrap: break-word; white-space: pre-wrap; ">

        else
        {
            sprintf( szProj4+strlen(szProj4),
                     &quot;+proj=omerc +lat_0=%.16g +lonc=%.16g +alpha=%.16g&quot;
                     &quot; +k=%.16g +x_0=%.16g +y_0=%.16g &quot;,
                     GetNormProjParm(SRS_PP_LATITUDE_OF_ORIGIN,0.0),
                     GetNormProjParm(SRS_PP_CENTRAL_MERIDIAN,0.0),
                     GetNormProjParm(SRS_PP_AZIMUTH,0.0),
                     GetNormProjParm(SRS_PP_SCALE_FACTOR,1.0),
                     GetNormProjParm(SRS_PP_FALSE_EASTING,0.0),
                     GetNormProjParm(SRS_PP_FALSE_NORTHING,0.0) );
        }</pre></span></div>There seems to be some uncertainty about this parameter. How can this be resolved and how can I help?<div><br></div><div>Thanks.</div><div><br clear="all"><span style="font-size:large"><i><font face="garamond, serif"><b><font color="#FF6600">Hilmy</font></b></font></i></span><br>


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