Custom scene navigation commands
NarrowFOV.vb
' Copyright 2010 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 ESRI.ArcGIS.Analyst3D
Imports ESRI.ArcGIS.Controls
Imports ESRI.ArcGIS.ADF.BaseClasses
Imports ESRI.ArcGIS.ADF.CATIDs
Imports System.Runtime.InteropServices

<ComClass(NarrowFOV.ClassId, NarrowFOV.InterfaceId, NarrowFOV.EventsId)> _
Public NotInheritable Class NarrowFOV
    Inherits BaseCommand

#Region "COM GUIDs"
    ' These  GUIDs provide the COM identity for this class 
    ' and its COM interfaces. If you change them, existing 
    ' clients will no longer be able to access the class.
    Public Const ClassId As String = "8379C5D4-AC6D-4BC9-90B9-D95BC4BE6828"
    Public Const InterfaceId As String = "C9A26C63-31EC-4CE0-A4C8-2476E40717D1"
    Public Const EventsId As String = "226947BD-DBCD-448E-907B-C5ADE3CF5373"
#End Region
#Region "COM Registration Function(s)"
    <ComRegisterFunction(), ComVisibleAttribute(False)> _
    Public Shared Sub RegisterFunction(ByVal registerType As Type)
        ' Required for ArcGIS Component Category Registrar support
        ArcGISCategoryRegistration(registerType)

        'Add any COM registration code after the ArcGISCategoryRegistration() call

    End Sub

    <ComUnregisterFunction(), ComVisibleAttribute(False)> _
    Public Shared Sub UnregisterFunction(ByVal registerType As Type)
        ' Required for ArcGIS Component Category Registrar support
        ArcGISCategoryUnregistration(registerType)

        'Add any COM unregistration code after the ArcGISCategoryUnregistration() call

    End Sub

#Region "ArcGIS Component Category Registrar generated code"
    ''' <summary>
    ''' Required method for ArcGIS Component Category registration -
    ''' Do not modify the contents of this method with the code editor.
    ''' </summary>
    Private Shared Sub ArcGISCategoryRegistration(ByVal registerType As Type)
        Dim regKey As String = String.Format("HKEY_CLASSES_ROOT\CLSID\{{{0}}}", registerType.GUID)
        ControlsCommands.Register(regKey)

    End Sub
    ''' <summary>
    ''' Required method for ArcGIS Component Category unregistration -
    ''' Do not modify the contents of this method with the code editor.
    ''' </summary>
    Private Shared Sub ArcGISCategoryUnregistration(ByVal registerType As Type)
        Dim regKey As String = String.Format("HKEY_CLASSES_ROOT\CLSID\{{{0}}}", registerType.GUID)
        ControlsCommands.Unregister(regKey)

    End Sub

#End Region
#End Region

    Private m_pSceneHookHelper As ISceneHookHelper

  ' A creatable COM class must have a Public Sub New() 
  ' with no parameters, otherwise, the class will not be 
  ' registered in the COM registry and cannot be created 
  ' via CreateObject.
    Public Sub New()
        MyBase.New()

        MyBase.m_category = "Sample_SceneControl(VB.NET)"
        MyBase.m_caption = "Narrow Field of View"
        MyBase.m_toolTip = "Narrow Field of View"
        MyBase.m_name = "Sample_SceneControl(VB.NET)/Narrow Field of View"
        MyBase.m_message = "Narrow Field of View"

        Dim res() As String = GetType(NarrowFOV).Assembly.GetManifestResourceNames()
        If res.GetLength(0) > 0 Then
            MyBase.m_bitmap = New System.Drawing.Bitmap(GetType(NarrowFOV).Assembly.GetManifestResourceStream("SceneToolsVB.narrow.bmp"))
        End If
        m_pSceneHookHelper = New SceneHookHelperClass
    End Sub

    Public Overrides Sub OnCreate(ByVal hook As Object)
        m_pSceneHookHelper.Hook = hook
    End Sub

    Public Overrides ReadOnly Property Enabled() As Boolean
        Get
            If m_pSceneHookHelper.Hook Is Nothing Or m_pSceneHookHelper.Scene Is Nothing Then
                Return False
            Else
                Dim pCamera As ICamera = CType(m_pSceneHookHelper.Camera, ICamera)

                'Disable if orthographic (2D) view
                If pCamera.ProjectionType = esri3DProjectionType.esriOrthoProjection Then
                    Return False
                Else
                    Return True
                End If
            End If
        End Get
    End Property

    Public Overrides Sub OnClick()
        'Get scene viewer's camera
        Dim pCamera As ICamera = CType(m_pSceneHookHelper.Camera, ICamera)

        'Widen the field of view
        Dim dAngle As Double
        dAngle = pCamera.ViewFieldAngle
        pCamera.ViewFieldAngle = dAngle * 0.9

        'Redraw the scene viewer
        Dim pSceneViewer As ISceneViewer = CType(m_pSceneHookHelper.ActiveViewer, ISceneViewer)
        pSceneViewer.Redraw(False)
    End Sub
End Class