<!DOCTYPE html><html><head><title></title><style type="text/css">#qt P{margin-top:0px;margin-bottom:0px;}
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p.MsoNormal,p.MsoNoSpacing{margin:0}</style></head><body><div style="font-family:Arial;">Hi Philippe,<br></div><div style="font-family:Arial;"><br></div><div style="font-family:Arial;">The new behaviour is correct. See <a href="https://gdal.org/development/rfc/rfc73_proj6_wkt2_srsbarn.html#axis-order-issues">https://gdal.org/development/rfc/rfc73_proj6_wkt2_srsbarn.html#axis-order-issues</a> for the axis order issue, a change made in GDAL 3.0. You can find a solution in <a href="https://github.com/OSGeo/gdal/blob/v3.5.0/MIGRATION_GUIDE.TXT#L67">https://github.com/OSGeo/gdal/blob/v3.5.0/MIGRATION_GUIDE.TXT#L67</a> (calling <span class="font" style="font-family:menlo, consolas, monospace, sans-serif;">SetAxisMappingStrategy(OAMS_TRADITIONAL_GIS_ORDER)</span> on every <span class="font" style="font-family:menlo, consolas, monospace, sans-serif;">OGRSpatialReference</span> you use.<br></div><div style="font-family:Arial;"><br></div><div style="font-family:Arial;">Laurentiu<br></div><div style="font-family:Arial;"><br></div><div>On Tue, Oct 18, 2022, at 13:43, Philippe Lelong wrote:<br></div><blockquote type="cite" id="qt" style=""><div id="qt-divtagdefaultwrapper" style="font-size:12pt;color:rgb(0, 0, 0);font-family:Calibri, Helvetica, sans-serif;" dir="ltr"><p>Hi,<br></p><p><br></p><p>I have an app build against GDAL 3.4.1 and PROJ6, and the same app build against GDAL 2.1.3 and PROJ4. They are not giving the same result when using OGRCoordinateTransformation.<br></p><p><br></p><p>If I do<br></p><p><br></p><p><br></p><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">const</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">char</span><span style="color:rgb(192, 192, 192);"> </span>*<span style="color:rgb(9, 46, 100);">their</span><span style="color:rgb(192, 192, 192);"> </span>=<span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">"GEOGCS[\"WGS</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">84\",DATUM[\"WGS_1984\",SPHEROID[\"WGS</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0],UNIT[\"degree\",0.0174532925199433],AUTHORITY[\"EPSG\",\"4326\"]]"</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">const</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">char</span><span style="color:rgb(192, 192, 192);"> </span>*<span style="color:rgb(9, 46, 100);">our</span><span style="color:rgb(192, 192, 192);"> </span>=<span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">"+proj=longlat</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">+datum=WGS84</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">+ellps=WGS84</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">+no_defs</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 128, 0);">+over"</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">double</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">miX</span><span style="color:rgb(192, 192, 192);"> </span>=<span style="color:rgb(192, 192, 192);"> </span>-<span style="color:rgb(0, 0, 128);">17.4042</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 128, 0);">double</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">miY</span><span style="color:rgb(192, 192, 192);"> </span>=<span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 0, 128);">35.3333</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 0, 128);">OGRSpatialReference</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">theirReference</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">theirReference</span>.<span style="color:rgb(0, 103, 124);">importFromWkt</span>((<span style="color:rgb(128, 128, 0);">char</span>**)&<span style="color:rgb(9, 46, 100);">their</span>);<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 0, 128);">OGRSpatialReference</span><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">ourReference</span>;<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">ourReference</span>.<span style="color:rgb(0, 103, 124);">importFromProj4</span>(<span style="color:rgb(9, 46, 100);">our</span>);<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(128, 0, 128);">OGRCoordinateTransformation</span><span style="color:rgb(192, 192, 192);"> </span>*<span style="color:rgb(9, 46, 100);">trans</span><span style="color:rgb(192, 192, 192);"> </span>=<span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(0, 103, 124);">OGRCreateCoordinateTransformation</span>(&<span style="color:rgb(9, 46, 100);">theirReference</span>,<span style="color:rgb(192, 192, 192);"> </span>&<span style="color:rgb(9, 46, 100);">ourReference</span>);<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><span style="color:rgb(192, 192, 192);"> </span><span style="color:rgb(9, 46, 100);">trans</span>-><span style="color:rgb(0, 103, 124);">Transform</span>(<span style="color:rgb(0, 0, 128);">1</span>,<span style="color:rgb(192, 192, 192);"> </span>&<span style="color:rgb(9, 46, 100);">miX</span>,<span style="color:rgb(192, 192, 192);"> </span>&<span style="color:rgb(9, 46, 100);">miY</span>);<br></pre><pre style="margin-top:0px;margin-bottom:0px;"><br></pre><div>in the version build against GDAL 3.4.1/PROJ6 this code results in swapping miX and miY (i.e. miX = 35.3333 and miY = -17.4042) <br></div><p><br></p><p>The version build against GDAL 2.1.3/PROJ4 leaves miX and miY unchanged, which I believe is correct.<br></p><p><br></p><p>Any explanation for this behavior and which one is correct? Would I get the same result using PROJ8 ?<br></p><p><br></p><p>Thanks in advance<br></p><p>Philippe Lelong<br></p><p><br></p><p><br></p></div><div>_______________________________________________<br></div><div>gdal-dev mailing list<br></div><div><a href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a><br></div><div><a href="https://lists.osgeo.org/mailman/listinfo/gdal-dev">https://lists.osgeo.org/mailman/listinfo/gdal-dev</a><br></div><div><br></div></blockquote><div style="font-family:Arial;"><br></div></body></html>