Change FamilyInstance Orientation

[mizrachi_amir2]

Hi,

I have a code creating walls based on some constraints.

I am trying to add structural steel columns in each wall (in predefined margins) such that per each wall all added columns will be at the same orientation as the wall itself.

For instance (in red a single column sketched in the correct orientation as of the hosting wall): 

I am using this line of code for adding a single FamilyInstance in my wall:

FamilyInstance fi = doc.Create.NewFamilyInstance(geomLine.GetEndPoint(0), firstColumn, firstLevel, Autodesk.Revit.DB.Structure.StructuralType.Column);

I tried to change the column orientation using fi.GetTransform().BasisX and set its value but to no avail.

Any suggestions how can this be achieved?

[jeremy_tammik]

I assume those columns are vertical. There is a difference in column orientation between vertical and slanted columns:

• https://thebuildingcoder.typepad.com/blog/2011/03/slanted-column-cross-section-rotation.html

For vertical columns, as in your case, it is pretty simple: just look at the column LocationPoint Rotation property:

• https://www.revitapidocs.com/2024/43aea45e-dd1c-6a35-2fd5-1f99356708df.htm

[mizrachi_amir2]

Thank you, @jeremy_tammik.

Helped me a lot!

Eventually I did something like this to rotate the column on its place:

FamilyInstance famInst = doc.Create.NewFamilyInstance(geomLine.GetEndPoint(0), firstColumn, firstLevel, Autodesk.Revit.DB.Structure.StructuralType.Column);
Transform myTransform = famInst.GetTotalTransform();
Line myLine = Line.CreateUnbound(geomLine.GetEndPoint(0), myTransform.BasisZ);
famInst.Location.Rotate(myLine, angle);