buildingSMART / buildingSMART/IFC4.x-development

Is IfcAnnotation predefinedtype incomplete or deprecating some of the prior suggested userdefined types?

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Description

In IFC4 the documentation of IfcAnnotation recommends certain userdefined types such as "SurveyPoint", "SurveyArea", "ContourLine", "IsoBar", "IsoLux", etc.

In IFC4X3, IfcAnnotation as a leaf node has added new enumerated PredefinedTypes https://ifc43-docs.standards.buildingsmart.org/IFC/RELEASE/IFC4x3/HTML/lexical/IfcAnnotationTypeEnum.htm such as `ASBUILTAREA`, `ASBUILTLINE`, `ASBUILTPOINT`, `ASSUMEDAREA`, etc.

I was talking with Peshawa Mohammed, a Phd researcher in IFCs use in surveying and noted that some of these new predefined types overlap with the recommended userdefined types. This begs the question:

1. For example, because there is now `ASBUILTPOINT`, does this mean that we can remove the recommendation for the userdefined "SurveyPoint" value in the docs?
2. Alternatively, is `ASBUILTPOINT` too specific and only captures As-Built Points, as opposed to Points measured prior to construction or during construction? If so, why is the predefined too specific? Should there be variants `CONSTRUCTIONAREA` or simply something like `SURVEYPOINT` or `COGOPOINT`?
3. In addition, should other userdefined types be migrated into the predefined type too? Things like IsoBar, IsoLux and IsoTherm?
4. Finally, the documentation talks about "SurveyArea" being an ObjectType of an 'Annotation point', as well as a "SurveyArea" being an ObjectType of an "Annotation surface", but there is no way to distinguish between Annotation point and Annotation surface without first parsing the representation type (which is fine, except that the docs in that case should mention the exact representation type / identifiers / contexts / whatever).

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