topic Re: Revit Tpiece geometric analysis in Revit API Forum

Revit Tpiece geometric analysis

Andrej.Licanin — Fri, 30 Aug 2024 08:27:33 GMT

Hello everybody,

Im trying to make a function that will take in a tpiece and return a coefficient base on a table from DIN 1988-300:

I get T pieces by collecting family instances and checking the part type in the MEPModel field.

After that, I retrieved the connectors from the T piece and obtained the flow values, but I can't determine the coefficients based on just that. I would need some way to identify which connector is going straight and which one is branching off.

I thought the angle property could help me here, but no luck—in the families I'm looking at, they are all 0. Any idea how to tackle this problem? How would i determine which connector is comming from the side at a t piece?

Re: Revit Tpiece geometric analysis

jeremy_tammik — Fri, 30 Aug 2024 09:41:48 GMT

Yes. You can look at the connector coordinate system:

https://www.revitapidocs.com/2024/cb6d725d-654a-f6f3-fed0-96cc618a42f1.htm

Its Z axis point in the connector direction, so you can use that to determine the relative connector angles.

Re: Revit Tpiece geometric analysis

Andrej.Licanin — Mon, 02 Sep 2024 13:55:03 GMT

Thanks Jeremy,it works

Here is the code for the function:

public static Element AnalyzeTee2(Element element, Document doc) { Element elementAtAngle = null; // Check if the element is a FamilyInstance if (!PipeNetworkSplitter.isSplitter(element)) { return null; } List<Connector> tpieceConnectors = getConnectors(element); Connector connector1 = tpieceConnectors[0]; Connector connector2 = tpieceConnectors[1]; Connector connector3 = tpieceConnectors[2]; XYZ zVector1 = connector1.CoordinateSystem.BasisZ; XYZ zVector2 = connector2.CoordinateSystem.BasisZ; XYZ zVector3 = connector3.CoordinateSystem.BasisZ; if (AreVectorsParallel(zVector1,zVector2)) elementAtAngle = getConnectingConnector(connector3).Owner; if (AreVectorsParallel(zVector2,zVector3)) elementAtAngle = getConnectingConnector(connector1).Owner; if (AreVectorsParallel(zVector1,zVector3)) elementAtAngle = getConnectingConnector(connector2).Owner; return elementAtAngle; } public static bool AreVectorsParallel(XYZ vector1, XYZ vector2, double tolerance = 1e-6) { // Compute the cross product of the two vectors XYZ crossProduct = vector1.CrossProduct(vector2); // Check if the cross product is close to zero vector within the given tolerance return crossProduct.IsAlmostEqualTo(XYZ.Zero, tolerance); }

Re: Revit Tpiece geometric analysis

jeremy_tammik — Thu, 12 Sep 2024 09:39:37 GMT

Thank you for the confirmation! Shared on the blog for posterity:

https://thebuildingcoder.typepad.com/blog/2024/09/mep-cable-tray-bend-and-tee-analysis-1.html#3