Question: Why does BuildingElement not have any geometry?

[filipGG]

In my case I would like to be able to represent a wall as either a series of lines or as a polygon for thick walls.

I could store it as a custom property, but in my mind having actual geometry would make more sense.
What do you think?

[ogiel]

I agree that this would make sense to have (and something to want). Just checked and it is indeed not possible to create a geometry twin and give it a relationship to a building element (no relationships available).

Maybe make a PR that contains relationship between building element and geometry equally to relationship between architecture and geometry, and then create building element + geometry twin pairs for each element.

[filipGG]

Seems like I don't have permission to open a PR, but I agree and my suggestion would be to add this relationship to BuildingElement:

{
  "@type": "Relationship",
  "description": {
    "en": "A GeoJSON Geometry representing the position or extent of the BuildingElement."
  },
  "displayName": {
    "en": "geometry"
  },
  "maxMultiplicity": 1,
  "name": "geometry",
  "target": "dtmi:org:w3id:rec:Geometry;1",
  "writable": true
}