i'm trying to create beam system directly from face based roof using Revit API, get 3D profiles from roof, make beam system, etc., so far it works for planar roof faces, Revit API do provide an option for 3D case, but it doesn't work for me if i set is3D to true:
BeamSystem bs = rev.ActiveDocument.Create.NewBeamSystem(profile, sketchplane, direction, true);
from Revit SDK, it says "If the BeamSystem is 3D, the inputted sketchPlane must be a level, or an exception will be thrown out", so i used Level instead of SketchPlane but it won't even compile, any inside knowledge will be very much appreciated!