hello

i have a problem that i cannot quite resolve.

i have a simple XYZ Scatter line in a 3D chart, i then want to draw a circle, i use a smooth line series for this, at a point on the line, but i want the circlw to be perpendicular to the line.

here is some code i tried but i could never quite get the perpendicluar circle, i could get close but not perpendicular.  i am sure  it is just some basic maths that i am missing.  maybe some one out there can point out my error.

i draw a basic XYZ scatter line as follows.

' add a header label

Dim header As NLabel = NChartControl1.Labels.AddHeader("XY Scatter Line Chart")

header.TextStyle.FontStyle = New NFontStyle("Times New Roman", 18, FontStyle.Italic)

header.ContentAlignment = ContentAlignment.BottomRight

header.Location = New NPointL(New NLength(2, NRelativeUnit.ParentPercentage), New NLength(2, NRelativeUnit.ParentPercentage))

NChartControl1.Controller.Tools.Add(New NTrackballTool())

' apply predefined projection and lighting

'm_Chart.Projection.SetPredefinedProjection(PredefinedProjection.PerspectiveTilted)

'm_Chart.LightModel.SetPredefinedLightModel(PredefinedLightModel.NorthernLights)

m_Chart.Axis(StandardAxis.Depth).Visible = True

m_Chart.Enable3D = True

' add interlaced stripe to the Y axis

Dim linearScale As NLinearScaleConfigurator = New NLinearScaleConfigurator()

Dim stripStyle As NScaleStripStyle = New NScaleStripStyle(New NColorFillStyle(Color.Beige), Nothing, True, 0, 0, 1, 1)

stripStyle.SetShowAtWall(ChartWallType.Back, True)

stripStyle.SetShowAtWall(ChartWallType.Left, True)

stripStyle.Interlaced = True

linearScale.MajorGridStyle.SetShowAtWall(ChartWallType.Back, True)

' add the line

m_Line = CType(m_Chart.Series.Add(SeriesType.Line), NLineSeries)

m_Line.LineSegmentShape = LineSegmentShape.Line

m_Line.DataLabelStyle.Visible = False

m_Line.InflateMargins = True

m_Line.MarkerStyle.Visible = True

m_Line.MarkerStyle.Width = New NLength(1.5F, NRelativeUnit.ParentPercentage)

m_Line.MarkerStyle.Height = New NLength(1.5F, NRelativeUnit.ParentPercentage)

m_Line.Name = "Line Series"

' add xy values

For i As Integer = 1 To 40 Step 5

m_Line.Values.Add(i)

m_Line.XValues.Add(i)

m_Line.ZValues.Add(i)

Next

' instruct the line series to use x values

m_Line.UseXValues = True

m_Line.UseZValues = True

then on a button click i attmept to draw my circle perpendicular to the line at point 12,12,12  with  radius of 2.  my line has an angle of 45 degrees.