Shall we automatically extract nested geometries from facade elements?

[pawelbaran]

Description:

Recently I bumped against an issue related to querying solids and physical bounds of a curtain wall. I noticed that although a curtain element has a bounding box and solid representation with volume and area, its faces and edges collections are empty 🤯

This results with GeometryPrimitives query returning nothing due to the following lines:

Revit_Toolkit/Revit_Core_Engine/Query/GeometryPrimitives.cs

Lines 72 to 73 in f22d01a

	instanceGeometry = instanceGeometry.Where(x => !(x is Solid && ((Solid)x).Faces.IsEmpty)).ToList();
	geometry = geometry.Where(x => !(x is Solid && ((Solid)x).Faces.IsEmpty)).ToList();

The above trickles down to Solids, Faces, PhysicalBounds etc. queries, which all return nothing now. As long as this is correct if we map the process 1:1 against the curtain Element object, is seems a bit counterintuitive that we need to query each individual panel and mullion each time we want to get the geometry of a facade element.

It tempted to me to add a few lines extracting panels and mullions inside GeometryPrimitives query (using BH.Revit.Engine.Core.Query.ICurtainGrids), but it feels like a risky shortcut taken it touches the core of the entire geometry extraction process. So I wanted to check with everyone (@enarhi in particular, taken it is facade business) how do you feel about making the change:

1. Shall we extract nested elements from curtain ones automatically when querying geometry
2. If so, any opinions where should that happen?
3. What workflows will be affected and need to be tested?

All comments welcome.

[vietle-bh]

You've probably already noticed this: edges and faces are empty because the area and volume you see are of the wall's invisible enclosing box (in blue):

I would pick Yes on question 1, but don't know the project enough to answer 2 & 3.

[enarhi]

I'd say yes for 1, but make sure the current handling of pulling the elements within a CurtainWall does not result in duplicate geometry. For 3, the only workflow I'm aware of that would be effected is our general CurtainWall pull, which is covered as part of the PullFacadeElements test file

I'm not sure on 2, but happy to test to ensure it makes sense how it is implemented.

[pawelbaran]

For all interested, I will have another look at this issue from the perspective of diffing, so might come back with concrete proposals for actions 👍