Sorry, did not see the sketch, so added it here
Accepted solution
Hello @Anonymous this is not technically an API question but it can be applied and automated to a certain extent with a macro.
If you open the Macro Manager (Manage > Macros) then create a new Module (Application Tab) with language set to VB.NET. When SharpDevelop opens replace the entire contents of ThisApplication.vb with the below. Then Build the macro (Build > Build Solution). Close SharpDevelop. Then back within the Macro Manager select the tree branch of 'CentreDimValuesOnLine' and press run for each view required. If the view scale changes in a view you'll have to run the macro again.
Option Strict off
Imports System
Imports Autodesk.Revit.UI
Imports Autodesk.Revit.DB
Imports Autodesk.Revit.UI.Selection
Imports System.Collections.Generic
Imports System.Linq
<Autodesk.Revit.Attributes.Transaction(Autodesk.Revit.Attributes.TransactionMode.Manual)> _
<Autodesk.Revit.DB.Macros.AddInId("EF4F27C9-EE2D-410E-B676-F3600AA5F812")> _
Partial Public Class ThisApplication
Private Sub UpdateDimText(Doc As Document, Dm As Object, TxtH As Double, GFactor As Double)
Dm.ResetTextPosition()
Doc.Regenerate()
Dim SegOrig As XYZ = Dm.Origin 'Centre of dim line between extension lines
Dim TextPos As XYZ = Dm.TextPosition
Dim S1 As XYZ = SegOrig - TextPos
Dim S1n As XYZ = S1.Normalize
Dim Shift As XYZ = TextPos + S1 + (S1n * (TxtH / 2)) + (S1n * GFactor)
Dm.TextPosition = Shift
End Sub
Public Sub CentreDimValuesOnLine
If me.ActiveUIDocument Is Nothing Then Exit sub Else
Dim UIDoc As UIDocument = me.ActiveUIDocument
Dim Doc As Document = UIDoc.Document
Dim AcView As View = UIDoc.ActiveGraphicalView
Dim FEC As New FilteredElementCollector(Doc, Doc.ActiveView.Id)
Dim ECF As New ElementCategoryFilter(BuiltInCategory.OST_Dimensions)
Dim Els As List(Of Dimension) = FEC.WherePasses(ECF).WhereElementIsNotElementType.ToElements.Cast(Of Dimension).ToList
Dim T As Transform = Transform.Identity
T.BasisX = AcView.RightDirection
T.BasisY = AcView.UpDirection
T.BasisZ = AcView.ViewDirection
'Seems horizontal and vertical dimensions have a larger gap between the text and the blue origin dot
Const GapFactor = 0.75 / 2.5 '0.3
Using tx As New Transaction(Doc, "Adjust dim text position")
If tx.Start = TransactionStatus.Started Then
For i = 0 To Els.Count - 1
Dim Dm As Dimension = Els(i)
Dim Dm_Typ As DimensionType = Doc.GetElement(Dm.GetTypeId)
Dim TxtH_P As Parameter = Dm_Typ.Parameter(BuiltInParameter.TEXT_SIZE)
Dim TxtH As Double = TxtH_P.AsDouble * AcView.Scale
Dm.HasLeader = False
Dim LNdir As Line = TryCast(Dm.Curve, Line)
If LNdir Is Nothing Then Continue For Else
Dim LNdirV As XYZ = T.OfVector(LNdir.Direction)
Dim Sx As Double = CDbl(LNdirV.X.ToString("F8")) ^ 2
Dim Sy As Double = CDbl(LNdirV.Y.ToString("F8")) ^ 2
Dim GFactor As Double = 0
If Sx = 1 OrElse Sy = 1 Then 'Horizontal or vertical in view
GFactor = TxtH_P.AsDouble * GapFactor
GFactor *= AcView.Scale
End If
If Dm.Segments.Size = 0 Then
UpdateDimText(Doc, Dm, TxtH, GFactor)
Else
For si = 0 To Dm.Segments.Size - 1
Dim DSeg As DimensionSegment = Dm.Segments(si)
UpdateDimText(Doc, DSeg, TxtH, GFactor)
Next
End If
Next
tx.Commit()
End If
End Using
End Sub
End Class
The below is a further discussion that may be of interest to others dealing with the dimension text in the API.
In doing the above exercise I observed that when the dimension text is horizontal or vertical the gap between the bottom of the text and the blue dot representing the text origin increases. In the above I have therefore approximated this gap as follows:
Gap = 0.3 x Text Height
From 0.75mm Gap / 2.5mm Text Height
This above was checked against Arial 2.5mm and 5.0mm and seems fairly stable for differing angles between vertical and horizontal.
