The MassLevelData used when the surface is horizontal, planar, and at the same height as a MassLevelData
related to the same mass as the referenced face.
Namespace: Autodesk.Revit.DB.AnalysisAssembly: RevitAPI (in RevitAPI.dll) Version: 21.0.0.0 (21.1.1.109)
Since: 2012