Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.Geometry
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.EditorInput
Imports System.math
Public Class GILSclass1
    <CommandMethod("ROT")> _
Public Sub TestPline3d()
        Dim editor As Editor = Application.DocumentManager.MdiActiveDocument.Editor
        Dim db As Database = Application.DocumentManager.MdiActiveDocument.Database
        Dim trans As Transaction = db.TransactionManager.StartTransaction()
        Dim prEnt As New PromptEntityOptions("Select Entity to Rotate: ")
        Dim prEntRes As PromptEntityResult = editor.GetEntity(prEnt)
        If prEntRes.Status <> PromptStatus.OK Then Return
        Dim id As ObjectId = prEntRes.ObjectId
        Dim Ent As Object = trans.GetObject(id, OpenMode.ForRead)
        Dim prpt As New PromptPointOptions("Input Base Point: ")
        Dim prptres As PromptPointResult = editor.GetPoint(prpt)
        If prptres.Status <> PromptStatus.OK Then Return
        Dim Bp As Point3d = prptres.Value

        Dim prang As New PromptAngleOptions("Input Rotation Angle: ")
        Dim prangres As PromptDoubleResult = editor.GetAngle(prang)
        If prangres.Status <> PromptStatus.OK Then Return
        Dim Ang As Double = prangres.Value
        Ang = DTR(Ang)
        Rotate(Ent, Bp, Ang)

    End Sub

    Public Function Rotate(ByRef Ent As Object, _
                                 ByRef Bp As Point3d, _
                                 ByRef Ang As Double) As Object

        Dim vMatrix As Object
        vMatrix = CreateMatrix()

        vMatrix(0, 3) = -Bp.X
        vMatrix(1, 3) = -Bp.Y
        vMatrix(2, 3) = -Bp.Z

        Dim vRotate As Object
        vRotate = CreateMatrix()

        vRotate(0, 0) = Cos(Ang)
        vRotate(0, 1) = -Sin(Ang)
        vRotate(1, 0) = Sin(Ang)
        vRotate(1, 1) = Cos(Ang)

        Dim vTmpMatrix As Object
        vTmpMatrix = ConcatenateMatrices(vMatrix, vRotate)

        vMatrix(0, 3) = Bp.X
        vMatrix(1, 3) = Bp.Y
        vMatrix(2, 3) = Bp.Z

        vRotate = ConcatenateMatrices(vTmpMatrix, vMatrix)

        vRotate(0, 3) = -vRotate(0, 3)
        vRotate(1, 3) = -vRotate(1, 3)

        Ent.TransformBy(vRotate)

    End Function

    Public Function Pi() As Double
        Pi = Atan(1) * 4
    End Function

    Public Function DTR(ByVal dAng As Double) As Double
        DTR = dAng / 180 * Pi()
    End Function

    Public Function CreateMatrix() As Object

        Dim dMatrix(0 To 3, 0 To 3) As Double
        dMatrix(0, 0) = 1
        dMatrix(1, 1) = 1
        dMatrix(2, 2) = 1
        dMatrix(3, 3) = 1
        CreateMatrix = dMatrix

    End Function

    Public Function ConcatenateMatrices(ByRef vMatrix1 As Object, _
                                        ByRef vMatrix2 As Object) As Object
        Dim iOutSide As Integer
        Dim iInSide As Integer
        Dim iMathLoop As Integer
        Dim dResult(0 To 3, 0 To 3) As Double

        For iOutSide = 0 To 3
            For iInSide = 0 To 3
                dResult(iOutSide, iInSide) = 0
                For iMathLoop = 0 To 3
                    dResult(iOutSide, iInSide) = dResult(iOutSide, iInSide) + _
                    vMatrix1(iOutSide, iMathLoop) * vMatrix2(iMathLoop, iInSide)
                Next iMathLoop
            Next iInSide
        Next iOutSide
        ConcatenateMatrices = dResult
    End Function



End Class