topic Re: TopographySurface as reference in Revit API Forum

TopographySurface as reference

l.virone — Tue, 24 Aug 2021 13:17:38 GMT

Hello everyone,

I'm trying to create SpotElevation automatically on a TopographySurface but i can't find a way to convert the TopographySurface to a Reference (I'm using this method : doc.Create.NewSpotElevation()).

Is there a way to get the surface as a reference ?

Tks,

Virone Lorenzo

Re: TopographySurface as reference

Omar_Amen — Tue, 24 Aug 2021 16:08:24 GMT

the "TopographySurface" class inherits from the Element class so I think you can use the Reference class constructor to get the "TopographySurface" object as a Reference object:

public Reference(Element element)

Re: TopographySurface as reference

l.virone — Tue, 24 Aug 2021 17:30:31 GMT

Hi,

Tks for your suggestion, but i've tried this and it seems to ignore the reference and not create the SpotElevation :

Reference d = new Reference(ts); SpotDimension e = doc.Create.NewSpotElevation(current_view, d, p, p, p, p, true);

ts = TopographySurface

p = XYZ point

Re: TopographySurface as reference

l.virone — Wed, 25 Aug 2021 05:35:13 GMT

Hi,

After further tests, it seems like the constructor for reference works, but I can't create the SpotElevation (see pic).

The Reference object is the same as if I had created the SpotElevation manually in Revit but an error occurs while trying to create the SpotElevation using code.

Maybe it is the XYZ object in the SpotElevation creation method ? I'm sure the XY is on the Topography, but i put zero to the Z value ?

TopographySurface ts = doc.GetElement(id) as TopographySurface; XYZ p = new XYZ(x, y, 0); //x and y are calculated Reference r = new Reference(ts); try { SpotDimension e = doc.Create.NewSpotElevation(current_view, r, p, p, p, p, false); } catch (Exception e) { TaskDialog.Show("s", "Reference ID: " + r.ElementId.ToString() + "\n" + "Reference Type: " + r.ElementReferenceType + "\n\n\n" + e.ToString()); }

Tks

Re: TopographySurface as reference

Omar_Amen — Wed, 25 Aug 2021 13:17:28 GMT

Hi @l.virone!
may you call NewSpotElevation() func outside the TryCatch ? to get the original Revit exception error it may help for the error tracing!
I've searched about your problem and I think you have a problem in the point with Z=0 so u have to get the actual Z value on the surface!
I found that question on the forum with almost the same problem, so check this out I hope it will help:
"https://forums.autodesk.com/t5/revit-api-forum/how-to-create-spot-elevation-on-the-topographysurface/m-p/10003458"
How to create spot elevation on the TopographySurface? - Autodesk Community - Revit Products

Re: TopographySurface as reference

l.virone — Mon, 06 Sep 2021 07:23:06 GMT

Hi @Omar_Amen ,

I've tested a very simple method alone and outside a try-catch and it didn't work:

XYZ ps = new XYZ(0, 0, 0); SpotDimension es = doc.Create.NewSpotElevation(current_view, new Reference(topography), ps, ps, ps, ps, false);

Tks for the link but I had already found this topic and their conclusion was to use an existing SpotElevation and copy/paste it where we need it. It works BUT not if there are subregions (because ID is different, it's another topographysurface), which is the case with all my projects! So basically I need an ElevationSpot on each possible Subregions to make it works, and that's not conceivable...

I would like to find a better way to create these ElevationSpots automatically, but it seems very difficult...

Tks again and sorry for the delay in response,

Virone Lorenzo

Re: TopographySurface as reference

jeremy_tammik — Mon, 06 Sep 2021 10:54:08 GMT

Sorry for the naive question, but just to make sure: can you create the desired spot elevation on the toposurface manually through the end user interface? If so, maybe you can analyse the result in RevitLookup to find out more about what elements, properties and parameters are involved and how they need to be set up. If not, the API will probably not support this either.

Re: TopographySurface as reference

l.virone — Mon, 06 Sep 2021 11:51:15 GMT

Hi @jeremy_tammik ,

Do you mean create it manually in Revit ? Yes I can create it manually in all ViewTypes (2D plan, 2D section, 3D,...), in my test I'm using a basic ViewPlan.

I've analyzed above in the discussion (using Revit LookUp) the parameters of the point created by hand and I tried to do the same thing using code, I've achieved to get the same objects which have the same IDs and are of the same types, but impossible to create the point... (Below a new example)

This is a point created in Revit manually :

This is the reference property I get using code :

I must specify that that, it work on objects of others types (with just a correct X-Y, no need to specify Z) but not on TopographySurface objects.

Either the API does not support, or I missed something...

Tks,

Re: TopographySurface as reference

RPTHOMAS108 — Mon, 06 Sep 2021 20:23:23 GMT

This has come up before, you can't add a spot elevation to a topo but you can copy one onto it from another temporary location using ElementTransformUtils.

https://forums.autodesk.com/t5/revit-api-forum/how-to-create-spot-elevation-on-the-topographysurface/m-p/10210072/highlight/true#M54887

If you create a DirectShape at the model origin you can host the temporary spot elevation on the top face of this at 0,0,0 and then copy to the coordinates on the topo. To find such coords you can use ReferenceIntersector. Need to use a surface reference to host the temporary spot elevation.

Re: TopographySurface as reference

l.virone — Tue, 07 Sep 2021 06:03:27 GMT

Hi @RPTHOMAS108 ,

This solution is fine with me if it only needs one existing ElevationSpot, except when I perform the copy and the point is no longer on its original host (like a subregion), then the copy fails.

ElementTransformUtils.CopyElement(doc, existingSpot.Id, point);

I may have misunderstood, but it seems that the copied ElevationSpot must already be on the TopographySurface host which we want to copy the point.

Tks for your help

Re: TopographySurface as reference

RPTHOMAS108 — Tue, 07 Sep 2021 10:38:56 GMT

No it doesn't have to be hosted on another topo surface or pre-existing. It can be created on something that has a surface reference but not a datum element such as level. The below creates a randomised topo and places spot elevations on it. The spot elevations are copied from a single spot elevation hosted on a direct shape which is created for the purpose and deleted at the end.

Private Function Obj_210906a(ByVal commandData As Autodesk.Revit.UI.ExternalCommandData, ByRef message As String, ByVal elements As Autodesk.Revit.DB.ElementSet) As Result Dim UIDoc As UIDocument = commandData.Application.ActiveUIDocument If UIDoc Is Nothing Then Return Result.Cancelled Else Dim IntDoc As Document = UIDoc.Document Dim V As View = UIDoc.ActiveGraphicalView Dim SpotEl As Element = Nothing Dim DS As DirectShape = Nothing Dim Topo As Element = Nothing Dim Pts As New List(Of XYZ) Dim Nnum As Integer = 60 Dim Mnum As Integer = 40 Dim RND As New Random Dim Range As Integer() = New Integer() {Nnum / 3, Mnum / 3} Dim HeightLimits As Double() = New Double(1) {2 / 0.3048, 1 / 0.3048} For X = 0 To Range(0) - 1 For Y = 0 To Range(1) - 1 Dim H As Double = HeightLimits(0) + (RND.NextDouble() * (HeightLimits(1) - HeightLimits(0))) Dim Pt As New XYZ((X * 3) / 0.3048, (Y * 3) / 0.3048, H) Pts.Add(Pt) Next Next Using TR0 As New Transaction(IntDoc, "Create random topo") If TR0.Start = TransactionStatus.Started Then Topo = TopographySurface.Create(IntDoc, Pts) V.SetCategoryHidden(New ElementId(BuiltInCategory.OST_Topography), False) TR0.Commit() End If End Using Using Tg As New TransactionGroup(IntDoc, "Add topo spot elevation") If Tg.Start = TransactionStatus.Started Then 'Create direct shape to host spot elevation Using TR0 As New Transaction(IntDoc, "Spot elev") If TR0.Start = TransactionStatus.Started Then Dim PL As Plane = Plane.CreateByNormalAndOrigin(XYZ.BasisZ, XYZ.Zero) Dim SKP As SketchPlane = SketchPlane.Create(IntDoc, PL) DS = DirectShape.CreateElement(IntDoc, New ElementId(BuiltInCategory.OST_GenericModel)) Dim A0 As Arc = Arc.Create(PL, 1, 0, Math.PI) Dim A1 As Arc = Arc.Create(PL, 1, Math.PI, 2 * Math.PI) Dim CL As New CurveLoop CL.Append(A0) CL.Append(A1) Dim S As Solid = GeometryCreationUtilities.CreateExtrusionGeometry({CL}.ToList, -XYZ.BasisZ, 0.25) DS.SetShape(New GeometryObject() {S}.ToList) TR0.Commit() End If End Using 'Add spot elevation to top face of newly created direct shape. Using TR1 As New Transaction(IntDoc, "Spot elev") If TR1.Start = TransactionStatus.Started Then Dim GeomEl As GeometryElement = DS.Geometry(New Options With {.DetailLevel = ViewDetailLevel.Fine, .ComputeReferences = True}) Dim S0 As Solid = GeomEl.Where(Function(x) x.GetType = GetType(Solid)).Cast(Of Solid).Where(Function(x) x.Volume > 0).FirstOrDefault Dim TF As Face = Nothing For i = 0 To S0.Faces.Size - 1 Dim F As PlanarFace = TryCast(S0.Faces.Item(i), PlanarFace) If F Is Nothing Then Continue For Else If F.FaceNormal.IsAlmostEqualTo(XYZ.BasisZ) Then TF = F End If Next Dim P As XYZ = XYZ.Zero SpotEl = IntDoc.Create.NewSpotElevation(V, TF.Reference, P, P, P, P, False) TR1.Commit() End If End Using 'Copy onto topo Using TR2 As New Transaction(IntDoc, "Spot elev") If TR2.Start = TransactionStatus.Started Then For Each GP As XYZ In Pts Dim Els As List(Of ElementId) = ElementTransformUtils.CopyElement(IntDoc, SpotEl.Id, GP) Next IntDoc.Delete(New ElementId() {DS.Id, SpotEl.Id}.ToList) TR2.Commit() End If End Using Tg.Assimilate() End If End Using Return Result.Succeeded End Function

In a new empty project you should then end up with something like the below:

Re: TopographySurface as reference

l.virone — Wed, 08 Sep 2021 05:03:56 GMT

Hi @RPTHOMAS108,

Tks it works ! But only on the main topography surface and not on subcategories like subregions.

But it seems the problem is a Revit problem :

--> Manually in Revit, try to copy an ElevationSpot from an element to a sub-region and it will fail, it doesn't matter if you use CTRL+V or if you keep CTRL down and move the element, it will fail because the copied element is not on his host...

I think Revit temporary copy the Spot on the main topographySurface, and after the copy process Revit realizes that the host is not right because a sub-regions has a different Id.

This is why I would have liked to succeed in directly creating the points on a topographysurface.

And this is why I had believed it wasn't possible to duplicate from another element, the problem isn't the topographySurface but the sub-regions.

Someone know a way to bypass this problem ?

Thanks for the previous answers!