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<p>Hello Lucio<br>
</p>
<p>I'm not sure to understand your need. You want to perform a
transformation between two geocentric coordinate reference
systems (GeocentricCRS)? If this is the case, then as Johann
said the transformation can be approximated with a small
translation, scale and rotation. But the difference is typically
only a few hundred metres.<br>
</p>
<p>There is many geocentric CRS, and I'm not sure which one you
are interested in. For example on the following page:<br>
</p>
<p><a class="moz-txt-link-freetext" href="http://epsg-registry.org/">http://epsg-registry.org/</a><br>
</p>
<p>In the "type" field, select "Coordinate Reference System", then
"Geodetic CRS", then "Geocentric CRS". There is more than 100
entries matching this query.<br>
</p>
<p> Martin<br>
</p>
<p><br>
</p>
Le 01/04/16 01:57, lucio Piccoli a écrit :<br>
</div>
<blockquote cite="mid:BLU172-W12A248E87221B00B6413AA9F990@phx.gbl"
type="cite">
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<div dir="ltr">hi all
<div><br>
i need some help on converting a mesh model from local origin
cartesian (from a modelling tool) to a geocentric one.</div>
<div><br>
</div>
<div>i found the nice transform from WGS to (ECEF) GEOCENTRIC
which i use to transform the model origin to a geocentric
point.</div>
<div><br>
</div>
<div>
<div> CoordinateReferenceSystem targetCRS =
PredefinedCRS.GEOCENTRIC;</div>
<div> CoordinateReferenceSystem sourceCRS =
PredefinedCRS.WGS84_3D;</div>
<div> MathTransform tr =
CRS.findMathTransform(sourceCRS, targetCRS);</div>
</div>
<div><br>
</div>
<div>i wish to use this point as my local origin for the rest of
the model in geocentric coordinates.<br>
<br>
i do NOT want to transform every point to ECEF (origin earth
centre) , as it will introduce jitter to the visualation.</div>
<div>but rather transform the points to GEOCENTRIC coordinates
*relative* to my own origin.</div>
<div><br>
</div>
<div>does that make any sense?<br>
<br>
-lucio<br>
</div>
</div>
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