Create Linear Dimensions (.NET)

Linear dimensions can be aligned or rotated. Aligned dimensions have the dimension line parallel to the line along which the extension line origins lie. Rotated dimensions have the dimension line placed at an angle to the extension line origins.

You create linear dimensions by creating instances of the AlignedDimension and RotatedDimension objects. After you create an instance of a linear dimensions, you can modify the text, the angle of the text, or the angle of the dimension line. The following illustrations show how the type of linear dimension and the placement of the extension line origins affect the angle of the dimension line and text.

When you create an instance of an AlignedDimension object, you have the option to specify the extension line origins, the location of the dimension line, dimension text, and the dimension style to apply. If you do not pass any parameters into the AlignedDimension object constructor, the object is assigned a set of default property values.

The RotatedDimension object constructor offers the same options as the AlignedDimension object constructor, with one exception. The RotatedDimension object constructor takes an additional parameter that specifies the angle at which the dimension line is rotated.

Dimension joglines

Joglines on linear dimensions are not added through a set of properties, but extended data (Xdata). The application name responsible for dimension joglines is ACAD_DSTYLE_DIMJAG_POSITION. The following is an example of the Xdata structure that needs to be appended to a linear dimension.

VB.NET

'' Open the Registered Application table for read
Dim acRegAppTbl As RegAppTable
acRegAppTbl = <transaction>.GetObject(<current_database>.RegAppTableId, _
                                      OpenMode.ForRead)
 
'' Check to see if the app "ACAD_DSTYLE_DIMJAG_POSITION" is
'' registered and if not add it to the RegApp table
If acRegAppTbl.Has("ACAD_DSTYLE_DIMJAG_POSITION") = False Then
    Using acRegAppTblRec As RegAppTableRecord = New RegAppTableRecord()
 
        acRegAppTblRec.Name = "ACAD_DSTYLE_DIMJAG_POSITION"
 
        acRegAppTbl.UpgradeOpen()
 
        acRegAppTbl.Add(acRegAppTblRec)
        <transaction>.AddNewlyCreatedDBObject(acRegAppTblRec, True)
    End Using
End If
 
'' Create a result buffer to define the Xdata
Dim acResBuf As ResultBuffer = New ResultBuffer()
acResBuf.Add(New TypedValue(DxfCode.ExtendedDataRegAppName, _
                                    "ACAD_DSTYLE_DIMJAG_POSITION"))
acResBuf.Add(New TypedValue(DxfCode.ExtendedDataInteger16, 387))
acResBuf.Add(New TypedValue(DxfCode.ExtendedDataInteger16, 3))
acResBuf.Add(New TypedValue(DxfCode.ExtendedDataInteger16, 389))
acResBuf.Add(New TypedValue(DxfCode.ExtendedDataXCoordinate, _
                                    New Point3d(-1.26985, 3.91514, 0)))
 
'' Attach the Xdata to the dimension
<dimension_object>.XData = acResBuf

C#

// Open the Registered Application table for read
RegAppTable acRegAppTbl;
acRegAppTbl = <transaction>.GetObject(<current_database>.RegAppTableId,
                                      OpenMode.ForRead) as RegAppTable;
 
// Check to see if the app "ACAD_DSTYLE_DIMJAG_POSITION" is
// registered and if not add it to the RegApp table
if (acRegAppTbl.Has("ACAD_DSTYLE_DIMJAG_POSITION") == false)
{
    using (RegAppTableRecord acRegAppTblRec = new RegAppTableRecord())
    {
        acRegAppTblRec.Name = "ACAD_DSTYLE_DIMJAG_POSITION";
 
        acRegAppTbl.UpgradeOpen();
 
        acRegAppTbl.Add(acRegAppTblRec);
        <transaction>.AddNewlyCreatedDBObject(acRegAppTblRec, true);
    }
}
 
// Create a result buffer to define the Xdata
ResultBuffer acResBuf = new ResultBuffer();
acResBuf.Add(new TypedValue((int)DxfCode.ExtendedDataRegAppName,
                                         "ACAD_DSTYLE_DIMJAG_POSITION"));
acResBuf.Add(new TypedValue((int)DxfCode.ExtendedDataInteger16, 387));
acResBuf.Add(new TypedValue((int)DxfCode.ExtendedDataInteger16, 3));
acResBuf.Add(new TypedValue((int)DxfCode.ExtendedDataInteger16, 389));
acResBuf.Add(new TypedValue((int)DxfCode.ExtendedDataXCoordinate,
                                         new Point3d(-1.26985, 3.91514, 0)));
 
// Attach the Xdata to the dimension
<dimension_object>.XData = acResBuf;

VBA/ActiveX Code Reference

Dim DataType(0 To 4) As Integer
Dim Data(0 To 4) As Variant
Dim jogPoint(0 To 2) As Double
 
DataType(0) = 1001: Data(0) = "ACAD_DSTYLE_DIMJAG_POSITION"
DataType(1) = 1070: Data(1) = 387
DataType(2) = 1070: Data(2) = 3
DataType(3) = 1070: Data(3) = 389
 
jogPoint(0) = -1.26985: jogPoint(1) = 3.91514: jogPoint(2) = 0#
DataType(4) = 1010: Data(4) = jogPoint
 
' Attach the xdata to the dimension
<dimension_object>.SetXData DataType, Data

Create a rotated linear dimension

This example creates a rotated dimension in Model space.

VB.NET

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry
 
<CommandMethod("CreateRotatedDimension")> _
Public Sub CreateRotatedDimension()
    '' Get the current database
    Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
    Dim acCurDb As Database = acDoc.Database

    '' Start a transaction
    Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()

        '' Open the Block table for read
        Dim acBlkTbl As BlockTable
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, _
                                     OpenMode.ForRead)

        '' Open the Block table record Model space for write
        Dim acBlkTblRec As BlockTableRecord
        acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), _
                                        OpenMode.ForWrite)

        '' Create the rotated dimension
        Using acRotDim As RotatedDimension = New RotatedDimension()
            acRotDim.XLine1Point = New Point3d(0, 0, 0)
            acRotDim.XLine2Point = New Point3d(6, 3, 0)
            acRotDim.Rotation = 0.707
            acRotDim.DimLinePoint = New Point3d(0, 5, 0)
            acRotDim.DimensionStyle = acCurDb.Dimstyle

            '' Add the new object to Model space and the transaction
            acBlkTblRec.AppendEntity(acRotDim)
            acTrans.AddNewlyCreatedDBObject(acRotDim, True)
        End Using

        '' Commit the changes and dispose of the transaction
        acTrans.Commit()
    End Using
End Sub

C#

using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.Geometry;
 
[CommandMethod("CreateRotatedDimension")]
public static void CreateRotatedDimension()
{
    // Get the current database
    Document acDoc = Application.DocumentManager.MdiActiveDocument;
    Database acCurDb = acDoc.Database;

    // Start a transaction
    using (Transaction acTrans = acCurDb.TransactionManager.StartTransaction())
    {
        // Open the Block table for read
        BlockTable acBlkTbl;
        acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId,
                                        OpenMode.ForRead) as BlockTable;

        // Open the Block table record Model space for write
        BlockTableRecord acBlkTblRec;
        acBlkTblRec = acTrans.GetObject(acBlkTbl[BlockTableRecord.ModelSpace],
                                        OpenMode.ForWrite) as BlockTableRecord;

        // Create the rotated dimension
        using (RotatedDimension acRotDim = new RotatedDimension())
        {
            acRotDim.XLine1Point = new Point3d(0, 0, 0);
            acRotDim.XLine2Point = new Point3d(6, 3, 0);
            acRotDim.Rotation = 0.707;
            acRotDim.DimLinePoint = new Point3d(0, 5, 0);
            acRotDim.DimensionStyle = acCurDb.Dimstyle;

            // Add the new object to Model space and the transaction
            acBlkTblRec.AppendEntity(acRotDim);
            acTrans.AddNewlyCreatedDBObject(acRotDim, true);
        }

        // Commit the changes and dispose of the transaction
        acTrans.Commit();
    }
}

VBA/ActiveX Code Reference

Sub CreateRotatedDimension()
    Dim dimObj As AcadDimRotated
    Dim rotationAngle As Double
    Dim startExtPoint(0 To 2) As Double
    Dim endExtPoint(0 To 2) As Double
    Dim dimLinePoint(0 To 2) As Double
 
    ' Define the dimension
    rotationAngle = 0.707
    startExtPoint(0) = 0: startExtPoint(1) = 0: startExtPoint(2) = 0
    endExtPoint(0) = 6: endExtPoint(1) = 3: endExtPoint(2) = 0
    dimLinePoint(0) = 0: dimLinePoint(1) = 5: dimLinePoint(2) = 0
 
    ' Create the rotated dimension in Model space
    Set dimObj = ThisDrawing.ModelSpace. _
                                 AddDimRotated(startExtPoint, endExtPoint, _
                                               dimLinePoint, rotationAngle)
    ZoomAll
End Sub