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Coordinates of the IfcLocalPlacement/IfcCartesianPoint

This is not my expertise, but many times I heard some experts were saying:

“As long as something is using Cartesian coordinates it will never be a reality capture model of the built environment”

And those experts were correct.

As long as you see every Z-plane of your Cartesian coordinate system as being an equipotential surface of Earth, you are (knowingly) making a mistake / introducing a discrepancy. And this discrepancy is encoded by Coordinate Reference Systems (CRS), see ISO 19111.

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Great papers, and I completely agree with the proposal of a WKT addition. I personally wonder if you can actually simply only use the WKT format, with an EPSG code that is either present (if one exists) or not present (if it is a custom CRS) - after all, I think the WKT format is available for all current EPSG CRSes. Or perhaps I am mistaken. That would lead to cleaner data and less ambiguity about how to fill out the TargetCRS attributes.

@stefan.markic Do you mind if I link to your papers (with due credit) in my article?

@Moult Yes, of course you can cite my papers! Science is (should be) free and accessible to everyone interested!

Regarding WKT: Every EPSG code is basically an identifier for a specific WKT string - see epsg.io export options - the first representation is always the WKT. If using only WKT will get implemented throughout the industry - that is out of my/our hands. You need to consider that other formats (like GML-family) use EPSG codes extensively and are therefore becoming kind-of industry best-practice. But that is a discussion to be had over a couple of beers in my opinion.