ItemFactoryBaseNewFamilyInstance(Face, XYZ, XYZ, FamilySymbol) Method

Inserts a new instance of a family onto a face of an existing element, using a location, reference direction, and a type/symbol.

Namespace: Autodesk.Revit.Creation
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.0.0.0 (25.0.0.0)

Syntax

C++

Copy

public FamilyInstance NewFamilyInstance(
	Face face,
	XYZ location,
	XYZ referenceDirection,
	FamilySymbol symbol
)

Public Function NewFamilyInstance ( 
	face As Face,
	location As XYZ,
	referenceDirection As XYZ,
	symbol As FamilySymbol
) As FamilyInstance

public:
FamilyInstance^ NewFamilyInstance(
	Face^ face, 
	XYZ^ location, 
	XYZ^ referenceDirection, 
	FamilySymbol^ symbol
)

member NewFamilyInstance : 
        face : Face * 
        location : XYZ * 
        referenceDirection : XYZ * 
        symbol : FamilySymbol -> FamilyInstance

Parameters

face Face: A face of a geometry object.
location XYZ: Point on the face where the instance is to be placed.
referenceDirection XYZ: A vector that defines the direction of the family instance. Note that this direction defines the rotation of the instance on the face, and thus cannot be parallel to the face normal.
symbol FamilySymbol: A FamilySymbol object that represents the type of the instance that is to be inserted. Note that this symbol must represent a family whose FamilyPlacementType is WorkPlaneBased.

Return Value

FamilyInstance
An instance of the new object if creation was successful, otherwise .

Exceptions

Exception	Condition
ArgumentNullException	Thrown when a non-optional argument was null.
ArgumentException	Thrown when the function cannot get the Reference from the face, or, when the Family cannot be placed as line-based on an input face reference, because its FamilyPlacementType is not WorkPlaneBased
ArgumentsInconsistentException	Thrown when reference direction is parallel to face normal at insertion point.
InvalidOperationException	Thrown when Revit is unable to place the family instance.
ArgumentException	Thrown if The symbol is not active.

Remarks

Use this method to insert one family instance on a face of another element, using a point on the face and a vector to define the position and direction of the new symbol.

The type/symbol that is used must be loaded into the document before this method is called. Families and their symbols can be loaded using the Document.LoadFamily or Document.LoadFamilySymbol methods.

The host object must support insertion of instances, otherwise this method will fail. If the instances fails to be created an exception may be thrown.

Some Families, such as Beams, have more than one endpoint and are inserted in the same manner as single point instances. Once inserted, these linear family instances can have their endpoints changed by using the instance's Element.Location property.

Note: if the created family instance includes nested instances, the API framework will automatically regenerate the document during this method call.

Example

C++

Copy

void CreateLightFixtureOnWall(Autodesk.Revit.DB.Document document, Wall wall)
{
    FilteredElementCollector collector = new FilteredElementCollector(document);
    collector.OfClass(typeof(FamilySymbol)).OfCategory(BuiltInCategory.OST_LightingFixtures);
    FamilySymbol symbol = collector.FirstElement() as FamilySymbol;

    // The only way to get a Face to use with this NewFamilyInstance overload
    // is from Element.Geometry with ComputeReferences turned on
    Face face = null;
    Options geomOptions = new Options();
    geomOptions.ComputeReferences = true;
    GeometryElement wallGeom = wall.get_Geometry(geomOptions);
    foreach (GeometryObject geomObj in wallGeom)
    {
        Solid geomSolid = geomObj as Solid;
        if (null != geomSolid)
        {
            foreach (Face geomFace in geomSolid.Faces)
            {
                face = geomFace;
                break;
            }
            break;
        }
    }

    // Get the center of the wall 
    BoundingBoxUV bboxUV = face.GetBoundingBox();
    UV center = (bboxUV.Max + bboxUV.Min) / 2.0;
    XYZ location = face.Evaluate(center);
    XYZ normal = face.ComputeNormal(center);
    XYZ refDir = normal.CrossProduct(XYZ.BasisZ);

    FamilyInstance instance = document.Create.NewFamilyInstance(face, location, refDir, symbol);         
}

Private Sub CreateLightFixtureOnWall(document As Autodesk.Revit.DB.Document, wall As Wall)
    Dim collector As New FilteredElementCollector(document)
    collector.OfClass(GetType(FamilySymbol)).OfCategory(BuiltInCategory.OST_LightingFixtures)
    Dim symbol As FamilySymbol = TryCast(collector.FirstElement(), FamilySymbol)

    ' The only way to get a Face to use with this NewFamilyInstance overload
    ' is from Element.Geometry with ComputeReferences turned on
    Dim face As Face = Nothing
    Dim geomOptions As New Options()
    geomOptions.ComputeReferences = True
    Dim wallGeom As GeometryElement = wall.Geometry(geomOptions)
    For Each geomObj As GeometryObject In wallGeom
        Dim geomSolid As Solid = TryCast(geomObj, Solid)
        If geomSolid IsNot Nothing Then
            For Each geomFace As Face In geomSolid.Faces
                face = geomFace
                Exit For
            Next
            Exit For
        End If
    Next

    ' Get the center of the wall 
    Dim bboxUV As BoundingBoxUV = face.GetBoundingBox()
    Dim center As UV = (bboxUV.Max + bboxUV.Min) / 2.0
    Dim location As XYZ = face.Evaluate(center)
    Dim normal As XYZ = face.ComputeNormal(center)
    Dim refDir As XYZ = normal.CrossProduct(XYZ.BasisZ)

    Dim instance As FamilyInstance = document.Create.NewFamilyInstance(face, location, refDir, symbol)
End Sub

Reference

ItemFactoryBase Class

NewFamilyInstance Overload

Autodesk.Revit.Creation Namespace