Triply Use Case 6: Place 3D data at the correct angle

[wouterbeek]

Triply Use Case 6: Place 3D data at the correct angle

Description

3D BIM data typically does not include the angle in which the building should be placed. (E.g. the BIM file uses an "engineering CRS" which assumes that the front of the building lies at 0 degrees.) When I load the 3D object into my GeoSPARQL dataset, place it in the right spot and at the right height, the building may appear in an incorrect angle.

Actor

• Data Expert (who may not be a Geodata Expert)

Preconditions

• I have a 3D BIM object.
• I have some GeoSPARQL data.

Postconditions

• I have integrated my 3D BIM object into my GeoSPARQL data, such that the 3D object appears at the right angle.

Steps

1. I have a 3D BIM object that I convert to a 3D GeoSPARQL.
2. I have 2D data in GeoSPARQL that uses CRS IRI http://www.opengis.net/def/crs/EPSG/0/28992, which is specific to The Netherlands.
3. I have some way of specifying in GeoSPARQL at which angle the BIM object should be displayed.
4. When somebody queries my data, they can see the 3D GeoSPARQL object at the correct angle, e.g. the building does not tilt onto the road.

[FransKnibbe]

Related to issue #586: if GeoSPARQL could supply semantics for georeferencing 3D geometry that uses a local CRS, that would probably include a property for a rotation angle.

[ar-chad]

@wouterbeek, @FransKnibbe this is very related to #582

BIM files are georeferenced by setting ifcMapConversion attributes. Those settings do not change coordinates, but specify how to offset the model in 'engineering CRS'.

There is more extended information about this here: https://www.buildingsmart.org/wp-content/uploads/2020/02/User-Guide-for-Geo-referencing-in-IFC-v2.0.pdf