Shared versus Private Properties
buildingSMART’s IFC, COBie, and other BIM applications, distinguish between Shared and Private properties as follows:
Shared |
Defined by type as in shared or common values across multiple instances. |
Private |
Defined at the instance when unique property values for each instance of that type (1) add to the shared property values, or (2) redefine or override the shared property values. |
An instance can have (in order of strong to soft typing):
- Only shared property values inherited from its type.
- Shared property values inherited from its type, plus additional private property values.
- Shared property values inherited from its type, some of which are redefined on the instance.
- Shared property values inherited from it’s type, some of which are redefined on the instance, plus additional private property values.
- Only private property values.
IFC Viewers, such as the FZK Viewer, may display shared properties as PropertySets from entity type and private properties as PropertySets from entity.