Question:
I have as assembly with 2 plate parts, they are constrained to each other face to face by mate constraint. How to get their overlapped area and boundary.
Solution:
From API help: TransientBRep.ImprintBodies finds regions of faces on two bodies which overlap and creates new bodies where the faces are split at the edges of the overlaps. This does not modify the original bodies but creates new transient bodies that contain the imprints.
The code below illustrates how to get the overlapped areas of two bodies of one mate constraint. To display the area, the code creates the relevant client graphics and moves them aside of the original bodies. The area and edges are selectable.
Private Sub GetOverlappedArea()
'get active Inventor
Dim ThisApplication As Inventor.Application =
System.Runtime.InteropServices.Marshal.GetActiveObject("Inventor.Application")
' Get the active assembly document and its definition.
Dim doc As AssemblyDocument
doc = ThisApplication.ActiveDocument
Dim def As AssemblyComponentDefinition
def = doc.ComponentDefinition
'assume one constraint is Mate Constraint
Dim AConstraint As AssemblyConstraint
AConstraint = def.Constraints(1)
Dim oOccurrenceOne As ComponentOccurrence
oOccurrenceOne = AConstraint.OccurrenceOne
Dim oOccurrenceTwo As ComponentOccurrence
oOccurrenceTwo = AConstraint.OccurrenceTwo
' Get the bodies in part space as transient bodies.
Dim transBrep As TransientBRep
transBrep = invApp.TransientBRep
Dim body1 As SurfaceBody
Dim body2 As SurfaceBody
'assume the geometries in both occurrence are within the fist surface body
'of the native model
body1 = transBrep.Copy(oOccurrenceOne.Definition.SurfaceBodies(1))
body2 = transBrep.Copy(oOccurrenceTwo.Definition.SurfaceBodies(1))
' Transform the bodies to be in the location represented in the assembly.
Call transBrep.Transform(body1, oOccurrenceOne.Transformation)
Call transBrep.Transform(body2, oOccurrenceTwo.Transformation)
' Imprint the bodies.
Dim newBody1 As SurfaceBody
Dim newBody2 As SurfaceBody
Dim body1OverlapFaces As Faces
Dim body2OverlapFaces As Faces
Dim body1OverlapEdges As Edges
Dim body2OverlapEdges As Edges
Call ThisApplication.TransientBRep.ImprintBodies(body1, body2, True, newBody1, newBody2, _
body1OverlapFaces, body2OverlapFaces, _
body1OverlapEdges, body2OverlapEdges)
Dim matchingIndexList1(body1OverlapFaces.Count - 1) As Integer
Dim matchingIndexList2(body2OverlapFaces.Count - 1) As Integer
Dim i As Integer
For i = 1 To body1OverlapFaces.Count
' Find the indices of the overlapping face in the Faces collection.
Dim j As Integer
For j = 1 To newBody1.Faces.Count
If body1OverlapFaces.Item(i) Is newBody1.Faces.Item(j) Then
matchingIndexList1(i - 1) = j
Exit For
End If
Next
Dim body2Index As Integer
For j = 1 To newBody2.Faces.Count
If body2OverlapFaces.Item(i) Is newBody2.Faces.Item(j) Then
matchingIndexList2(i - 1) = j
Exit For
End If
Next
Next
' The code below creates new non-parametric base features using the new imprinted bodies
' so that the results can be visualized. The new bodies are created offset from the
' original so that they don't overlap and are more easily seen.
' Define a matrix to use in transforming the bodies.
Dim trans As Matrix
trans = ThisApplication.TransientGeometry.CreateMatrix
' Move the first imprinted body over based on the range so it doesn't lie on the original.
trans.Cell(1, 4) = (body1.RangeBox.MaxPoint.X - body1.RangeBox.MinPoint.X) * 1.1
Call ThisApplication.TransientBRep.Transform(newBody1, trans)
' Move the second imprinted body over based on the rangeso it doesn't lie on the original.
trans.Cell(1, 4) = trans.Cell(1, 4) + (body1.RangeBox.MaxPoint.X - body1.RangeBox.MinPoint.X) * 1.1
Call ThisApplication.TransientBRep.Transform(newBody2, trans)
'draw the point graphics
Dim oCoordSet As GraphicsCoordinateSet = Nothing
Dim oGraphicsNode As GraphicsNode = Nothing
Dim oDataSets As GraphicsDataSets = Nothing
'get datasets, dataset, graphics node for client graphics
getCG(oGraphicsNode, oCoordSet, oDataSets)
oGraphicsNode.Selectable = True
'add surface Graphics
Dim oBody1Graphics As SurfaceGraphics
oBody1Graphics = oGraphicsNode.AddSurfaceGraphics(newBody1)
oBody1Graphics.ChildrenAreSelectable = True
For i = 1 To oBody1Graphics.DisplayedFaces.Count
oBody1Graphics.DisplayedFaces.Item(i).Selectable = True
Next
Dim oBody2Graphics As SurfaceGraphics
oBody2Graphics = oGraphicsNode.AddSurfaceGraphics(newBody2)
oBody2Graphics.ChildrenAreSelectable = True
For i = 1 To oBody2Graphics.DisplayedFaces.Count
oBody2Graphics.DisplayedFaces.Item(i).Selectable = True
Next
ThisApplication.ActiveView.Update()
'Now the faces of client graphics are selectable. The overlapped faces can be selected.
'help function
Private Sub getCG(ByRef oGraphicsNode As Object, _
Optional ByRef oCoordSet As Object = Nothing, _
Optional ByRef oOutDataSets As Object = Nothing)
Dim oDoc As Document
oDoc = invApp.ActiveDocument
Dim oDataOwner As Object = Nothing
Dim oGraphicsOwner As Object = Nothing
'check the document type and get the owner of the datasets and graphics
If oDoc.DocumentType = DocumentTypeEnum.kPartDocumentObject Or oDoc.DocumentType = DocumentTypeEnum.kAssemblyDocumentObject Then
oDataOwner = oDoc
oGraphicsOwner = oDoc.ComponentDefinition
ElseIf oDoc.DocumentType = DocumentTypeEnum.kDrawingDocumentObject Then
If oDoc.ActiveSheet Is Nothing Then
MsgBox("The current document is a drawing. The command is supposed to draw client graphics on active sheet! But active sheet is null!")
Exit Sub
Else
oDataOwner = oDoc.ActiveSheet
oGraphicsOwner = oDoc.ActiveSheet
End If
End If
'delete the data sets and graphics if they exist
Try
oDataOwner.GraphicsDataSetsCollection("TestCG").Delete()
Catch ex As Exception
End Try
Try
oGraphicsOwner.ClientGraphicsCollection("TestCG").Delete()
Catch ex As Exception
End Try
'create DataSets
Dim oDataSets As GraphicsDataSets = oDataOwner.GraphicsDataSetsCollection.Add("TestCG")
oOutDataSets = oDataSets
'create one coordinate data set
oCoordSet = oDataSets.CreateCoordinateSet(oDataSets.Count + 1)
'create graphics node
Dim oClientGraphics As Inventor.ClientGraphics = oGraphicsOwner.ClientGraphicsCollection.Add("TestCG")
oGraphicsNode = oClientGraphics.AddNode(oClientGraphics.Count + 1)
End Sub
End Sub
