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<p>Javier,</p>
<p>I've addressed this in <a class="moz-txt-link-freetext" href="https://github.com/OSGeo/PROJ/pull/3270">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 class="moz-cite-prefix">Le 29/07/2022 à 21:16, Javier Jimenez
Shaw a écrit :<br>
</div>
<blockquote type="cite"
cite="mid:CADRrdKvtn3q7YXymWYesPkJ4KuB0PmTENoAosBvBgh9S6adu=A@mail.gmail.com">
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<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" class="gmail_signature"
data-smartmail="gmail_signature">.___ ._ ..._ .. . ._.
.___ .. __ . _. . __.. ... .... ._ .__<br>
Entre dos pensamientos racionales <br>
hay infinitos pensamientos irracionales.<br>
<br>
</div>
</div>
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</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
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