<div dir="ltr">Thank you Even.<br clear="all"><div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature">.___ ._ ..._ .. . ._.  .___ .. __ . _. . __..  ... .... ._ .__<br>Entre dos pensamientos racionales <br>hay infinitos pensamientos irracionales.<br><br></div></div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Sat, 30 Jul 2022 at 19:35, Even Rouault <<a href="mailto:even.rouault@spatialys.com">even.rouault@spatialys.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
  
    
  
  <div>
    <p>Javier,</p>
    <p>I've addressed this in <a href="https://github.com/OSGeo/PROJ/pull/3270" target="_blank">https://github.com/OSGeo/PROJ/pull/3270</a>.<br>
    </p>
    <p>Regarding the WKT issue, I've raised this to the OGC CRS SWG list
      as the grammar of WKT doesn't allow currently a unitless
      parameter, even if the EPSG Vertical Offset and Slope method
      requires it. I'd suggest using something like UNIT["none",1]
      instead of ANGLEUNIT["arc-second",4.8481368111E-06], until that's
      cleared up</p>
    <p>Even<br>
    </p>
    <div>Le 29/07/2022 à 21:16, Javier Jimenez
      Shaw a écrit :<br>
    </div>
    <blockquote type="cite">
      
      <div dir="ltr">
        <div>Hi</div>
        <div><br>
        </div>
        <div>Thanks to Even's PR #3200 "Implement Vertical Offset and
          slope transformation method", I am trying to use a Derived
          Vertical CRS using the conversion method "Vertical Offset and
          Slope" (that will be a perfect combination with "Affine
          parametric transformation" in the horizontal... I hope)<br>
        </div>
        <div><br>
        </div>
        <div>The WKT2 I have created is this</div>
        <div><span style="font-family:monospace"><br>
          </span></div>
        <div><span style="font-family:monospace">VERTCRS["Custom
            Vertical",<br>
                BASEVERTCRS["EGM2008 height",<br>
                    VDATUM["EGM2008 geoid"]],<br>
                DERIVINGCONVERSION["vertical offs. and slope",<br>
                    METHOD["Vertical Offset and Slope",<br>
                        ID["EPSG",1046]],<br>
                    PARAMETER["Ordinate 1 of evaluation
            point",46.9166666666669,<br>
                        ANGLEUNIT["degree",0.0174532925199433],<br>
                        ID["EPSG",8617]],<br>
                    PARAMETER["Ordinate 2 of evaluation
            point",8.18333333333361,<br>
                        ANGLEUNIT["degree",0.0174532925199433],<br>
                        ID["EPSG",8618]],<br>
                    PARAMETER["Vertical Offset",-0.245,<br>
                        LENGTHUNIT["metre",1],<br>
                        ID["EPSG",8603]],<br>
                    PARAMETER["Inclination in latitude",-0.21,<br>
                        ANGLEUNIT["arc-second",4.8481368111E-06],<br>
                        ID["EPSG",8730]],<br>
                    PARAMETER["Inclination in longitude",-0.032,<br>
                        ANGLEUNIT["arc-second",4.8481368111E-06],<br>
                        ID["EPSG",8731]],<br>
                    PARAMETER["EPSG code for Horizontal CRS",4326,<br>
                        ANGLEUNIT["arc-second",4.8481368111E-06],<br>
                        ID["EPSG",1037]]],<br>
                CS[vertical,1],<br>
                    AXIS["gravity-related height (H)",up,<br>
                        LENGTHUNIT["metre",1]],<br>
                USAGE[<br>
                    SCOPE["unknown"],<br>
                    AREA["World"],<br>
                    BBOX[-90,-180,90,180]]]  </span><br>
        </div>
        <div><br>
        </div>
        <div>The first strange thing is that without the unit in the
          parameter "EPSG code for Horizontal CRS", <span style="font-family:monospace">projinfo "$(cat
            derived_vertical.wkt)"</span> shows a warning:</div>
        <div><span style="font-family:monospace">Warning: Parsing error
            : syntax error, unexpected ID. Error occurred around:<br>
                        ID["EPSG",1037]]],</span></div>
        <div><br>
        </div>
        <div>When I try to see how the conversion would be with the
          command</div>
        <div><span style="font-family:monospace">projinfo -s EPSG:3855
            -t "$(cat derived_vertical.wkt)"</span></div>
        <div>I get</div>
        <div><span style="font-family:monospace">PROJ string:<br>
            Error when exporting to PROJ string: Unsupported conversion
            method: Vertical Offset and Slope</span></div>
        <div><br>
        </div>
        <div>Using it in a compound crs and using cs2cs does not get the
          proper transformation neither.</div>
        <div><br>
        </div>
        <div>Am I creating the WKT2 string properly to create a derived
          vertical crs (to be used in a compound) with that conversion
          method?</div>
        <div><br>
        </div>
        <div>Thanks</div>
        <div><br>
        </div>
        <div>PS. I am using master from today</div>
        <div>PS2.  <span style="font-family:monospace">projinfo -s
            EPSG:5728 -t EPSG:5730</span> shows a coordinate operation
          that uses "Vertical Offset and Slope", with a nice PROJ string</div>
        <div><br>
        </div>
        <div>
          <div>
            <div dir="ltr">.___ ._ ..._ .. . ._. 
              .___ .. __ . _. . __..  ... .... ._ .__<br>
              Entre dos pensamientos racionales <br>
              hay infinitos pensamientos irracionales.<br>
              <br>
            </div>
          </div>
        </div>
      </div>
      <br>
      <fieldset></fieldset>
      <pre>_______________________________________________
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</pre>
    </blockquote>
    <pre cols="72">-- 
<a href="http://www.spatialys.com" target="_blank">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
  </div>

</blockquote></div>