Creating a toolbar of globe tools
PolylineTool.vb
' Copyright 2012 ESRI
' 
' All rights reserved under the copyright laws of the United States
' and applicable international laws, treaties, and conventions.
' 
' You may freely redistribute and use this sample code, with or
' without modification, provided you include the original copyright
' notice and use restrictions.
' 
' See the use restrictions.
' 

Imports Microsoft.VisualBasic
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.IO
Imports ESRI.ArcGIS.ADF.BaseClasses
Imports ESRI.ArcGIS.ADF.CATIDs
Imports System.Windows.Forms
Imports ESRI.ArcGIS.Geometry
Imports ESRI.ArcGIS.Analyst3D
Imports ESRI.ArcGIS.Carto
Imports ESRI.ArcGIS.Display

Namespace GlobeGraphicsToolbar
  Public Class PolylineTool
    Inherits ESRI.ArcGIS.Desktop.AddIns.Tool
    Private _polylineGeometry As PolylineGeometry = Nothing
    Private Const LeftButton As Integer = 1
        Private Const GeographicCoordinateSystem As ESRI.ArcGIS.Geometry.esriSRGeoCSType = ESRI.ArcGIS.Geometry.esriSRGeoCSType.esriSRGeoCS_WGS1984
    Private Const PointElementSize As Double = 1
        Private Const PointElementStyle As ESRI.ArcGIS.Display.esriSimpleMarkerStyle = ESRI.ArcGIS.Display.esriSimpleMarkerStyle.esriSMSCircle
    Private Const PolylineElementWidth As Double = 1000
        Private Const PolylineElementStyle As ESRI.ArcGIS.Display.esriSimpleLineStyle = ESRI.ArcGIS.Display.esriSimpleLineStyle.esriSLSSolid
    Private Const GraphicsLayerName As String = "Globe Graphics"

    Public Sub New()
    End Sub

    Protected Overrides Sub OnUpdate()

    End Sub

    Protected Overrides Sub OnMouseDown(ByVal arg As ESRI.ArcGIS.Desktop.AddIns.Tool.MouseEventArgs)
      If arg.Button = MouseButtons.Left Then
        Dim geographicCoordinates As New GeographicCoordinates(ArcGlobe.Globe, arg.X, arg.Y)

        Dim spatialReferenceFactory As New SpatialReferenceFactory(CInt(Fix(GeographicCoordinateSystem)))

        Dim pointGeometry As New PointGeometry(geographicCoordinates.Longitude, geographicCoordinates.Latitude, geographicCoordinates.AltitudeInKilometers, spatialReferenceFactory.SpatialReference)

        If _polylineGeometry Is Nothing Then
          _polylineGeometry = New PolylineGeometry(spatialReferenceFactory.SpatialReference)
        End If

        _polylineGeometry.AddPoint(TryCast(pointGeometry.Geometry, IPoint))

        Dim tableOfContents As New TableOfContents(ArcGlobe.Globe)

        If (Not tableOfContents.LayerExists(GraphicsLayerName)) Then
          tableOfContents.ConstructLayer(GraphicsLayerName)
        End If

        Dim layer As New Layer(tableOfContents(GraphicsLayerName))

        If _polylineGeometry.PointCount = 1 Then
          Dim pointElement As New PointElement(pointGeometry.Geometry, PointElementSize, PointElementStyle)

          layer.AddElement(pointElement.Element, pointElement.ElementProperties)
        Else
          layer.RemoveElement(layer.ElementCount - 1)

          Dim polylineElement As New PolylineElement(_polylineGeometry.Geometry, PolylineElementWidth, PolylineElementStyle)

          layer.AddElement(polylineElement.Element, polylineElement.ElementProperties)
        End If

        ArcGlobe.Globe.GlobeDisplay.RefreshViewers()
      End If
    End Sub

    Protected Overrides Sub OnDoubleClick()
      _polylineGeometry = Nothing
    End Sub
  End Class

End Namespace