How to import your 3d revit model into Dynamo in Plan view

Hello everyone,

I am currently making a script for isovist and was wondering what would be a ‘smart’ way of importing your 3d Revit model into Dynamo - however in a 2D / Plan view.

I am using this node called Visiblity.IsovistFromPoint which needs three inputs - point, boundary and obstruction.

Is there a way where I can set the floor as the boundary and walls as obstruction ? The input requirement for those two are polygons.

Thank you in advance and please let me know if you need more information from my end.