Geolocation standards in IFC2X3 and IFC4

Developers
16

Thanks for publishing the guide. I haven’t read through in detail, but after a quick skim I see a few issues that might need to be corrected:

  • The psets in IFC2X3 are nominated as ePSet_.... This creates an inconsistency in naming. I propose to rename it either to ePset_... or EPset_.... The S is not capitalised in all other pset names.
  • Page 14 misses out some of the properties in table 2 for projected CRS. Also typo for IfcGrid.
  • Page 15 of the user guide does not clarify exactly how the name is taken from the EPSG list. The screenshot shows the value EPSG:28356, which is good, but it is ambiguous as to exactly how it is derived from the EPSG list. My proposal in this thread about specifying the XPath can clarify this.
  • Again, Page 15 shows a description value in the screenshot. Should this not be derived from the EPSG registry? Why is it seemingly set to a custom arbitrary value here?
  • Again, Page 15 seems to show the exact same value in the MapProjection field as well as in the Name field. This seems incorrect. See the XPath clarification in the post above.
  • To prevent repetition, the user guide seems to miss out on the three proposals in this thread, which still seem to be unresolved issues. It would be good to integrate these 3 proposals into the user guide.

If somebody were able to point at the correct Git location to create a pull request, I would be able to help integrate these changes into the official IFC documentation.

@john.mitchell - I would be happy to clarify these points in person if need be.

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