Client Graphics - Triangle

Public Sub DrawCustomTriangles()
    Dim oDoc As Document
    Set oDoc = ThisApplication.ActiveDocument

    ' Set a reference to component definition of the active document.
    ' This assumes that a part or assembly document is active.
    Dim oCompDef As ComponentDefinition
    Set oCompDef = ThisApplication.ActiveDocument.ComponentDefinition
    
    ' Check to see if the test graphics data object already exists.
    ' If it does clean up by removing all associated of the client graphics
    ' from the document.  If it doesn't create it and draw a line.
    On Error Resume Next
    Dim oGraphicsData As GraphicsDataSets
    Set oGraphicsData = oDoc.GraphicsDataSetsCollection.Item("SampleGraphicsID")
    If Err.Number = 0 Then
        On Error GoTo 0
        ' An existing client graphics object was successfully obtained so clean up.
        oGraphicsData.Delete
        oCompDef.ClientGraphicsCollection.Item("SampleGraphicsID").Delete
    
        ' update the display to see the results.
        ThisApplication.ActiveView.Update
    Else
        Err.Clear
        On Error GoTo 0
        
        ' Set a reference to the transient geometry object for user later.
        Dim oTransGeom As TransientGeometry
        Set oTransGeom = ThisApplication.TransientGeometry
        
        ' Create a graphics data set object.  This object contains all of the
        ' information used to define the graphics.
        Dim oDataSets As GraphicsDataSets
        Set oDataSets = oDoc.GraphicsDataSetsCollection.Add("SampleGraphicsID")
        
        ' Create a coordinate set.
        Dim oCoordSet As GraphicsCoordinateSet
        Set oCoordSet = oDataSets.CreateCoordinateSet(1)

        ' Get the number of sides for the cylinder.
        Dim iSideCount As Long
        iSideCount = InputBox("Enter number of sides for the cylinder.  (Must be greater than 2.)", "Cylinder Tolerance", 25)
        
        Dim dRadius As Double
        Dim dHeight As Double
        dRadius = 3
        dHeight = 7
        
        ' Create an array containing points to used in drawing the cylinder.
        ' The points could also be directly defined in a coordinate set, but
        ' defining them in array and then setting the coordinates using the
        ' array is more efficient for a large set of points.
        Dim adPointCoords() As Double
        ReDim adPointCoords(1 To ((iSideCount + 1) * 2) * 3) As Double
        Dim i As Long
        Dim dAngle As Double
        
        ' Define the points for the outline of the first end of the cylinder.
        dAngle = 0
        For i = 0 To iSideCount - 1
            adPointCoords(i * 3 + 1) = dRadius * Cos(dAngle)
            adPointCoords(i * 3 + 2) = dRadius * Sin(dAngle)
            adPointCoords(i * 3 + 3) = 0
            
            ' Increment the angle for the next point
            dAngle = dAngle + ((2 * 3.14159265358979) / iSideCount)
        Next
        
        ' Define the points for the outline of the other end of the cylinder.
        dAngle = 0
        For i = iSideCount To (iSideCount * 2) - 1
            adPointCoords(i * 3 + 1) = dRadius * Cos(dAngle)
            adPointCoords(i * 3 + 2) = dRadius * Sin(dAngle)
            adPointCoords(i * 3 + 3) = dHeight
            
            ' Increment the angle for the next point
            dAngle = dAngle + ((2 * 3.14159265358979) / iSideCount)
        Next
        
        ' Define coordinate at the center of the first end of the cylinder.
        adPointCoords((iSideCount * 2) * 3 + 1) = 0
        adPointCoords((iSideCount * 2) * 3 + 2) = 0
        adPointCoords((iSideCount * 2) * 3 + 3) = 0
        
        ' Define coordinate at the center of the other end of the cylinder.
        adPointCoords((iSideCount * 2) * 3 + 4) = 0
        adPointCoords((iSideCount * 2) * 3 + 5) = 0
        adPointCoords((iSideCount * 2) * 3 + 6) = dHeight

        ' Assign the points to the coordinate set.
        Call oCoordSet.PutCoordinates(adPointCoords)
        
        ' Create an index set to use for the triangle fan for
        ' cap of the first end of the cylinder.  This will
        ' serve as in index look-up into the coordinate set.
        Dim oCap1Index As GraphicsIndexSet
        Set oCap1Index = oDataSets.CreateIndexSet(1)
        
        ' Set the index values.  This could also be done by setting the
        ' value in an array and then using the array to set the values
        ' of the index set.  Using an array is more efficient, but this
        ' is used to here to demonstrate the IndexSet object's Add method.
        Call oCap1Index.Add(1, iSideCount * 2 + 1)
        Call oCap1Index.Add(2, 1)
        Call oCap1Index.Add(3, 2)
        For i = 4 To iSideCount + 1
            Call oCap1Index.Add(i, i - 1)
        Next
        Call oCap1Index.Add(iSideCount + 2, 1)

        ' Create an index set to use for the triangle fan of the other cylinder cap.
        Dim oCap2Index As GraphicsIndexSet
        Set oCap2Index = oDataSets.CreateIndexSet(2)
        
        ' Set the index values.
        Call oCap2Index.Add(1, iSideCount * 2 + 2)
        Call oCap2Index.Add(2, iSideCount + 1)
        Call oCap2Index.Add(3, iSideCount + 2)
        For i = 4 To iSideCount + 1
            Call oCap2Index.Add(i, i + iSideCount - 1)
        Next
        Call oCap2Index.Add(iSideCount + 2, iSideCount + 1)

        ' Create an index set to use for the triangle strip that will
        ' define the sides of the cylinder.
        Dim oCylinderIndex As GraphicsIndexSet
        Set oCylinderIndex = oDataSets.CreateIndexSet(3)

        ' Define the index values in an array.
        Dim iIndexValues() As Long
        ReDim iIndexValues(1 To (iSideCount + 1) * 2) As Long
        For i = 0 To iSideCount - 1
            iIndexValues(i * 2 + 1) = i + 1
            iIndexValues(i * 2 + 2) = i + iSideCount + 1
        Next
        iIndexValues(((iSideCount + 1) * 2) - 1) = 1
        iIndexValues((iSideCount + 1) * 2) = iSideCount + 1

        ' Define the index values in the index set using the array.
        Call oCylinderIndex.PutIndices(iIndexValues)

        ' Create the ClientGraphics object.
        Dim oClientGraphics As ClientGraphics
        Set oClientGraphics = oCompDef.ClientGraphicsCollection.Add("SampleGraphicsID")
       
        ' Create a new graphics node within the client graphics objects.
        Dim oCylinderNode As GraphicsNode
        Set oCylinderNode = oClientGraphics.AddNode(1)

        ' Create a triangle fan for cap 1 of the cylinder.
        Dim oCap1TriangleFan As TriangleFanGraphics
        Set oCap1TriangleFan = oCylinderNode.AddTriangleFanGraphics

        ' Set the coordinates and index set for the cap.
        oCap1TriangleFan.CoordinateSet = oCoordSet
        oCap1TriangleFan.CoordinateIndexSet = oCap1Index

        ' Create a triangle fan for cap 2 of the cylinder.
        Dim oCap2TriangleFan As TriangleFanGraphics
        Set oCap2TriangleFan = oCylinderNode.AddTriangleFanGraphics

        ' Set the coordinates and index set for the cap.
        oCap2TriangleFan.CoordinateSet = oCoordSet
        oCap2TriangleFan.CoordinateIndexSet = oCap2Index

        ' Create a triangle string for the sides of the cylinder.
        Dim oCylinderStrip As TriangleStripGraphics
        Set oCylinderStrip = oCylinderNode.AddTriangleStripGraphics

        ' Set the coordinates and index set for the cap.
        oCylinderStrip.CoordinateSet = oCoordSet
        oCylinderStrip.CoordinateIndexSet = oCylinderIndex
        
        Dim oAppearance As Asset
        Set oAppearance = oDoc.AppearanceAssets(1)

        oCylinderNode.Appearance = oAppearance

        ' update the display to see the results.
        ThisApplication.ActiveView.Update
        
        ' Define a normal for cap 1.
        Dim oCap1Normals As GraphicsNormalSet
        Set oCap1Normals = oDataSets.CreateNormalSet(1)
        Call oCap1Normals.Add(1, oTransGeom.CreateUnitVector(0, 0, -1))
        
        ' Assign the normals to the cap.
        oCap1TriangleFan.NormalSet = oCap1Normals
        
        ' Define a normal for cap 2.
        Dim oCap2Normals As GraphicsNormalSet
        Set oCap2Normals = oDataSets.CreateNormalSet(2)
        Call oCap2Normals.Add(1, oTransGeom.CreateUnitVector(0, 0, 1))
   
        ' Assign the normals to the cap.
        oCap2TriangleFan.NormalSet = oCap2Normals
        
        ' Create an array that contains the normals for each vertex of the cylinder.
        Dim adNormals() As Double
        ReDim adNormals(1 To ((iSideCount + 1) * 2) * 3) As Double
        dAngle = 0
        For i = 0 To iSideCount
            Dim dX As Double
            Dim dY As Double
            dX = Cos(dAngle)
            dY = Sin(dAngle)
            adNormals(i * 6 + 1) = dX
            adNormals(i * 6 + 2) = dY
            adNormals(i * 6 + 3) = 0
            adNormals(i * 6 + 4) = dX
            adNormals(i * 6 + 5) = dY
            adNormals(i * 6 + 6) = 0

            ' Increment the angle for the next normal.
            dAngle = dAngle + ((2 * 3.14159265358979) / iSideCount)
        Next
        
        ' Create and set the normal set for the cylinder.
        Dim oCylinderNormals As GraphicsNormalSet
        Set oCylinderNormals = oDataSets.CreateNormalSet(3)
        Call oCylinderNormals.PutNormals(adNormals)
        
        ' Assign the normals to the cylinder.
        oCylinderStrip.NormalSet = oCylinderNormals
        
        ' update the display to see the results.
        ThisApplication.ActiveView.Update
    End If
End Sub