Custom scene navigation commands
ZoomInOut.cs
// 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.
// 

using System;
using ESRI.ArcGIS.Analyst3D;
using ESRI.ArcGIS.Geometry;
using ESRI.ArcGIS.Controls;
using ESRI.ArcGIS.ADF.BaseClasses;
using ESRI.ArcGIS.ADF.CATIDs;
using System.Runtime.InteropServices;

namespace sceneTools
{
  [ClassInterface(ClassInterfaceType.None)]
  [Guid("C0624E23-6085-4e46-9ED1-25CE20A972E9")]

  public sealed class ZoomInOut : BaseTool
  {
    [DllImport("user32")] public static extern int SetCapture(int hwnd); 
    [DllImport("user32")] public static extern int GetCapture(int fuFlags);
    [DllImport("user32")] public static extern int ReleaseCapture(int hwnd);

        #region COM Registration Function(s)
        [ComRegisterFunction()]
        [ComVisible(false)]
        static void RegisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryRegistration(registerType);

            //
            // TODO: Add any COM registration code here
            //
        }

        [ComUnregisterFunction()]
        [ComVisible(false)]
        static void UnregisterFunction(Type registerType)
        {
            // Required for ArcGIS Component Category Registrar support
            ArcGISCategoryUnregistration(registerType);

            //
            // TODO: Add any COM unregistration code here
            //
        }

        #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 static void ArcGISCategoryRegistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Register(regKey);

        }
        /// <summary>
        /// Required method for ArcGIS Component Category unregistration -
        /// Do not modify the contents of this method with the code editor.
        /// </summary>
        private static void ArcGISCategoryUnregistration(Type registerType)
        {
            string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
            ControlsCommands.Unregister(regKey);

        }

        #endregion
        #endregion

    private System.Windows.Forms.Cursor m_pCursor;
    private ISceneHookHelper m_pSceneHookHelper;
    private long m_lMouseX, m_lMouseY;
    private bool m_bInUse;

    public ZoomInOut()
    {
      base.m_category = "Sample_SceneControl(C#)";
      base.m_caption = "Zoom In/Out";
      base.m_toolTip = "Zoom In/Out";
      base.m_name = "Sample_SceneControl(C#)/Zoom In/Out";
      base.m_message = "Dynamically zooms in and out on the scene";

      //Load resources
      string[] res = GetType().Assembly.GetManifestResourceNames();
      if(res.GetLength(0) > 0)
      {
        base.m_bitmap = new System.Drawing.Bitmap(GetType().Assembly.GetManifestResourceStream("sceneTools.ZoomInOut.bmp"));
      }
      m_pCursor = new System.Windows.Forms.Cursor(GetType().Assembly.GetManifestResourceStream("sceneTools.ZOOMINOUT.CUR"));
    
      m_pSceneHookHelper = new SceneHookHelperClass ();
    }

    public override bool Enabled
    {
      get
      {
        if(m_pSceneHookHelper.Scene == null)
          return false;
        else
          return true;
      }
    }
  
    public override void OnCreate(object hook)
    {
      m_pSceneHookHelper.Hook = hook;
    }

    public override int Cursor
    {
      get
      {
        return m_pCursor.Handle.ToInt32();
      }
    }
  
    public override bool Deactivate()
    {
      return true;
    }
  
    public override void OnMouseDown(int Button, int Shift, int X, int Y)
    {
      //Initialize mouse coordinates
      m_bInUse = true;
      m_lMouseX = X;
      m_lMouseY = Y;

      SetCapture(m_pSceneHookHelper.ActiveViewer.hWnd);
    }
  
    public override void OnMouseMove(int Button, int Shift, int X, int Y)
    {
      if(!m_bInUse) return;

      //Differences between previous and current mouse coordinates
      long dx, dy;
      dx = X - m_lMouseX;
      dy = Y - m_lMouseY;

      if(dx == 0 && dy == 0) return;

      //Get the scene viewer's camera
      ICamera pCamera = (ICamera) m_pSceneHookHelper.Camera;

      //Zoom camera
      if(dy < 0)
        pCamera.Zoom(1.1);
      else if(dy > 0)
        pCamera.Zoom(0.9);

      //Set mouse coordinates for the next OnMouseMove event
      m_lMouseX = X;
      m_lMouseY = Y;

      //Redraw the scene viewer
      ISceneViewer pSceneViewer = (ISceneViewer) m_pSceneHookHelper.ActiveViewer;
      pSceneViewer.Redraw(true);
    }
  
    public override void OnMouseUp(int Button, int Shift, int X, int Y)
    {
      if(!m_bInUse) return;
  
      if(GetCapture(m_pSceneHookHelper.ActiveViewer.hWnd) != 0)
        ReleaseCapture(m_pSceneHookHelper.ActiveViewer.hWnd);

      m_bInUse = false;
    }
  }
}