Conversions and Transformations using the Solid Edge API – Part 1

Introduction

Conversions from different reference systems and translations of spatial data is a common requirement in design automation using Solid Edge.

This series of articles discusses the following:

1. Document Unit Conversion – ParseUnit and Format Unit methods of the UnitsOfMeasure object.


2. View Coordinate Conversion – ViewToSheet and SheetToView methods of the DrawingView object.


3. 2D to 3D Conversion – Convert2DCoordinate method of the Profile object.


4. 3D to 2D Transformations – ModelToView method of the DrawingView object.


5. Assembly Transformations – GetMatrix and PutMatrix methods of the Occurrence object.

Units of Measure

The following code snippet draws a triangle i.e. 3 lines with the length simply specified as 3 and height of 4.

Sub Main()

  Dim seApp As SolidEdgeFramework.Application = System.Runtime.InteropServices.Marshal.GetActiveObject(“SolidEdge.Application”)

  Dim seDoc As SolidEdgeDraft.DraftDocument = seApp.ActiveDocument

  Dim seSheet As SolidEdgeDraft.Sheet = seDoc.ActiveSheet

 

  Dim dLength As Double = 3

  Dim dHeight As Double = 4

  Dim seLine As SolidEdgeFrameworkSupport.Line2d = Nothing
  seLine = seSheet.Lines2d.AddBy2Points(0, 0, dLength, 0)

  seLine = seSheet.Lines2d.AddBy2Points(dLength, 0, dLength, dHeight)

  seLine = seSheet.Lines2d.AddBy2Points(dLength, dHeight, 0, 0)

End Sub

When the Draft document has its units set to mm, the triangle is drawn as seen in the image below: 

Compare the size of the triangle with the A4 size sheet which is 297 x 210 mm.

The triangle appears disproportionately large because the length and height of 3 and 4 are interpreted by Solid Edge as 3 meters and 4 meters since this is the default unit of measure also called the database unit. This is irrespective of the document’s unit which could be inches or mm.

3 meter is 3000 mm which explains the relative sizes of the background sheet and the line lengths.

For drawing the lines of the correct size, the input values need to be converted to the document units without actually finding the document units separately. For this the ParseUnit method of the UnitsOfMeasure object can be used as shown in bold below:

Sub Main()

  Dim seApp As SolidEdgeFramework.Application = System.Runtime.InteropServices.Marshal.GetActiveObject(“SolidEdge.Application”)

  Dim seDoc As SolidEdgeDraft.DraftDocument = seApp.ActiveDocument

  Dim seSheet As SolidEdgeDraft.Sheet = seDoc.ActiveSheet

 

  Dim dLength As Double = 3

  Dim dHeight As Double = 4

  Dim seUOM As SolidEdgeFramework.UnitsOfMeasure = seDoc.UnitsOfMeasure
  dLength = seUOM.ParseUnit(UnitTypeConstants.igUnitDistance, dLength)

  dHeight = seUOM.ParseUnit(UnitTypeConstants.igUnitDistance, dHeight)
  Dim seLine As SolidEdgeFrameworkSupport.Line2d = Nothing

  seLine = seSheet.Lines2d.AddBy2Points(0, 0, dLength, 0)

  seLine = seSheet.Lines2d.AddBy2Points(dLength, 0, dLength, dHeight)

  seLine = seSheet.Lines2d.AddBy2Points(dLength, dHeight, 0, 0)

End Sub

Now when the lines are drawn, selecting one of them displays its length in the Command bar which is correctly displayed as that specified in the code.

Similarly, when you read values or distance measurements from Solid Edge using the API methods, they are returned in default unit which is meters. To convert it to a display unit use the FormatUnit method.

For example, here’s a piece of code adapted from @JasonTitcomb‘s EyeDropper for Solid Edge which displays the length of an edge in the status bar when the mouse hovers over an edge of a Part or Sheetmetal model.

Imports System.Runtime.InteropServices

Imports SolidEdgeFramework

Module Module1

  Private mSolidApp As SolidEdgeFramework.Application = Nothing

  Private mCommand As Command = Nothing

  Private mMouse As Mouse = Nothing

  Private seUoM As UnitsOfMeasure = Nothing
  Public Sub main()

    mSolidApp = TryCast(Marshal.GetActiveObject(“SolidEdge.Application”), SolidEdgeFramework.Application)
    seUoM = mSolidApp.ActiveDocument.UnitsOfMeasure

    mCommand = mSolidApp.CreateCommand(SolidEdgeConstants.seCmdFlag.seNoDeactivate)
    AddHandler mCommand.Terminate, AddressOf command_Terminate

    mCommand.Start()

    mMouse = mCommand.Mouse
    With mMouse

      .LocateMode = 1

      .WindowTypes = 1

      .EnabledMove = True

      .AddToLocateFilter(SolidEdgeConstants.seLocateFilterConstants.seLocateEdge)
      AddHandler .MouseMove, AddressOf mouse_MouseMove

End With
    System.Windows.Forms.Application.Run()

End Sub
Private Sub mouse_MouseMove(ByVal sButton As Short, ByVal sShift As Short, ByVal dX As Double, ByVal dY As Double, ByVal dZ As Double, ByVal pWindowDispatch As Object, ByVal lKeyPointType As Integer, ByVal pGraphicDispatch As Object)

  Dim theEdge As SolidEdgeGeometry.Edge = DirectCast(pWindowDispatch, SolidEdgeGeometry.Edge)

  Dim EdgeLength As Double, MinParam As Double, MaxParam As Double
  If theEdge IsNot Nothing Then

    theEdge.GetParamExtents(MinParam, MaxParam)

    theEdge.GetLengthAtParam(MinParam, MaxParam, EdgeLength)

    EdgeLength = seUoM.FormatUnit(UnitTypeConstants.igUnitDistance, EdgeLength, PrecisionConstant:=SolidEdgeConstants.PrecisionConstants.igPrecisionThousandths)
    mSolidApp.StatusBar = EdgeLength.ToString

  End If

End Sub

Without the FormatUnit method of the UnitsOfMeasure object, the value displayed in the status bar is in meter irrespective of the unit of the document.

When FormatUnit is used, the same program displays the length of the edge in the document unit without any changes or conversion.

In the next part of this series, I will show you in depth how to convert coordinates of a point on the drawing sheet to the window to create a brand new command called Zoom to Selection.

Meanwhile, if you have any questions regarding this article, kindly post them on the Solid Edge Developer Forum.

Tushar Suradkar

www.CADVertex.com

www.SurfAndCode.IN

Solid Edge User Group on FaceBook:

https://www.facebook.com/groups/solidedgeusers/