Scale Objects

You scale an object by specifying a base point and scale factor based on the current drawing units. You can scale all drawing objects, as well as attribute reference objects.

To scale an object, use the Scaling function of a transformation matrix. This function requires a numeric value for the scale factor of the object and a Point3d object for the base point of the scaling operation. The Scaling function scales the object equally in the X, Y, and Z directions. The dimensions of the object are multiplied by the scale factor. A scale factor greater than 1 enlarges the object. A scale factor between 0 and 1 reduces the object.

NoteIf you need to scale an object non-uniformly, you need to initialize a transformation matrix using the appropriate data array and then use the TransformBy method of the object. For more information on initializing a transformation matrix with a data array, see Transform Objects.

For more information about scaling, see “Resize or Reshape Objects” in the AutoCAD User's Guide.

Scale a polyline

This example creates a closed lightweight polyline and then scales the polyline by 0.5 from the base point (4,4.25,0).

VB.NET

Imports Autodesk.AutoCAD.Runtime

Imports Autodesk.AutoCAD.ApplicationServices

Imports Autodesk.AutoCAD.DatabaseServices

Imports Autodesk.AutoCAD.Geometry

<CommandMethod("ScaleObject")> _

Public Sub ScaleObject()

  '' Get the current document and 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 a lightweight polyline

      Dim acPoly As Polyline = New Polyline()

      acPoly.AddVertexAt(0, New Point2d(1, 2), 0, 0, 0)

      acPoly.AddVertexAt(1, New Point2d(1, 3), 0, 0, 0)

      acPoly.AddVertexAt(2, New Point2d(2, 3), 0, 0, 0)

      acPoly.AddVertexAt(3, New Point2d(3, 3), 0, 0, 0)

      acPoly.AddVertexAt(4, New Point2d(4, 4), 0, 0, 0)

      acPoly.AddVertexAt(5, New Point2d(4, 2), 0, 0, 0)

      '' Close the polyline

      acPoly.Closed = True

      '' Reduce the object by a factor of 0.5

      '' using a base point of (4,4.25,0)

      acPoly.TransformBy(Matrix3d.Scaling(0.5, New Point3d(4, 4.25, 0)))

      '' Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acPoly)

      acTrans.AddNewlyCreatedDBObject(acPoly, True)

      '' Save the new objects to the database

      acTrans.Commit()

  End Using

End Sub

using Autodesk.AutoCAD.Runtime;

using Autodesk.AutoCAD.ApplicationServices;

using Autodesk.AutoCAD.DatabaseServices;

using Autodesk.AutoCAD.Geometry;

[CommandMethod("ScaleObject")]

public static void ScaleObject()

  // Get the current document and 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 a lightweight polyline

      Polyline acPoly = new Polyline();

      acPoly.AddVertexAt(0, new Point2d(1, 2), 0, 0, 0);

      acPoly.AddVertexAt(1, new Point2d(1, 3), 0, 0, 0);

      acPoly.AddVertexAt(2, new Point2d(2, 3), 0, 0, 0);

      acPoly.AddVertexAt(3, new Point2d(3, 3), 0, 0, 0);

      acPoly.AddVertexAt(4, new Point2d(4, 4), 0, 0, 0);

      acPoly.AddVertexAt(5, new Point2d(4, 2), 0, 0, 0);

      // Close the polyline

      acPoly.Closed = true;

      // Reduce the object by a factor of 0.5

      // using a base point of (4,4.25,0)

      acPoly.TransformBy(Matrix3d.Scaling(0.5, new Point3d(4, 4.25, 0)));

      // Add the new object to the block table record and the transaction

      acBlkTblRec.AppendEntity(acPoly);

      acTrans.AddNewlyCreatedDBObject(acPoly, true);

      // Save the new objects to the database

      acTrans.Commit();

VBA/ActiveX Code Reference