ifc 4x3 Geolocation formatting correct ?

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Hello,

I received a IFC 4x3 with a geolocation information, that I have never seeing and want to confirm if this is “correct\allow” by the standards, as reading the documentation I am confused and not sure if is valid.

to origin: (0.,0.,0.) and directions x(1.,0.,0.), y(0.,1.,0.), z(0.,0.,1.) are missing.

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“If an geographic placement is provided using IfcMapConversion then the WorldCoordinateSystem atttibute is used to define the offset between the zero point of the local engineering coordinate system and the geographic reference point to which the IfcMapConversion offset relates. In preferred practise both points (also called “project base point” and “survey point”) should be coincidental. However it is possible to offset the geographic reference point from the local zero point.”

Thank you

2

So the map conversion reads:

Eastings=0
Northings=0
OrthogonalHeight=0
XAxisAbscissa=NIL
XAxisOrdinate=NIL

I don’t know why in the schema E+N are required but the XAxis is optional, but essentially I would read this as all empty. I don’t think there is much you can do with this, but it’s not invalid per the schema.

If you’re primarily talking about the WorldCoordinateSystem placement, then yes, only the point is required, if the direction vectors are missing you are supposed to assume no rotation

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