How to make call Class Function (Code supplied)

Could someone please show me the syntax to make the functions work in the code below. The code draws a circle on a picture box but I don't know how to execute it. Help!
Gmoney


Private Sub picCanvas_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
Dim gobj as Object
Dim cdrawingobjects as Collection

    With Picture1
           .DrawMode = vbInvert
           .FillStyle = vbFSTransparent
           .DrawWidth = 1
    End With
           
    siFirstX = X
    siFirstY = Y
    siLastX = X
    siLastY = Y

    Set gobj = New cls_draw_Circle
    With gobj
         .X0 = (siFirstX + siLastX) / 2
         .X0 = (siFirstX + siLastX) / 2
         .Radius = 80
    End With
   
    cDrawingObjects.Add gobj
    Set gobj.Picture1 = Form1.Picture1
    gobj.Draw
End Sub

The following is the code for DrawCircle Class :
Option Explicit

' The PictureBox we draw on.
Public picCanvas As PictureBox

' The rectangle's drawing attributes.
Public X0 As Single
Public Y0 As Single
Public Radius As Single
Public DrawWidth As Integer
Public ForeColor As OLE_COLOR
Public FillColor As OLE_COLOR
Public FillStyle As FillStyleConstants
Public DrawStyle As DrawStyleConstants

' Default property values.
Private Const m_def_X0 = 0
Private Const m_def_Y0 = 0
Private Const m_def_Radius = 80
Private Const m_def_DrawWidth = 1
Private Const m_def_ForeColor = vbBlack
Private Const m_def_FillColor = vbBlack
Private Const m_def_FillStyle = vbBlack
Private Const m_def_DrawStyle = vbSolid

' Draw on picCanvas.
Public Sub Draw()

   Form1.Picture1.ForeColor = ForeColor
   ' Set other drawing attributes.
   With fmyform(iCurrentProcId).picCanvas
       .FillStyle = FillStyle
       .FillColor = FillColor
       .DrawWidth = DrawWidth
       .DrawStyle = DrawStyle
   End With

   ' Draw the object.
   Form1.Picture1.Circle (X0, Y0), Radius, Form1.Picture1.ForeColor
End Sub

' Set default property values.
Private Sub SetDefaultProperties()
   X0 = m_def_Y0
   Y0 = m_def_X0
   Radius = m_def_Radius
   DrawWidth = m_def_DrawWidth
   ForeColor = m_def_ForeColor
   FillColor = m_def_FillColor
   FillStyle = m_def_FillStyle
   DrawStyle = m_def_DrawStyle
End Sub

' Set some defaults.
Private Sub Class_Initialize()
   SetDefaultProperties
End Sub