Событие перетаскавание

/*http://esate.ru, TaoOpenGLister*/

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
// для работы с библиотекой OpenGL 
using Tao.OpenGl;
// для работы с библиотекой FreeGLUT 
using Tao.FreeGlut;
// для работы с элементом управления SimpleOpenGLControl 
using Tao.Platform.Windows;

namespace View3D
{
   public partial class Form1 : Form
   {
      int x, y;
      double AlphaX,AlphaY;
      bool MouseIsDown;
      public Form1()
      {
        AlphaX = 45;
        AlphaY = 45;
        
        InitializeComponent();
        AnT.InitializeContexts();

        Init();
        Draw();
        
        Gl.glFlush();
        AnT.Invalidate();
      }

      private void Init()
      {
        Glut.glutInit();
        Glut.glutInitDisplayMode(Glut.GLUT_RGB | Glut.GLUT_DOUBLE | Glut.GLUT_DEPTH);
        Gl.glClearColor(0, 0, 0, 1);
        Gl.glViewport(0, 0, AnT.Width, AnT.Height);
        Gl.glMatrixMode(Gl.GL_PROJECTION);
        Gl.glLoadIdentity();
        Glu.gluPerspective(45, (float)AnT.Width / (float)AnT.Height, 0.1, 200);
        Gl.glMatrixMode(Gl.GL_MODELVIEW);
        Gl.glLoadIdentity();
        Gl.glEnable(Gl.GL_DEPTH_TEST);
        Glu.gluLookAt(10, 10, 10, 0, 0, 0, 0, 0, 1); 
      }

      private void Draw()
      {
        Gl.glClear(Gl.GL_COLOR_BUFFER_BIT | Gl.GL_DEPTH_BUFFER_BIT);
        Gl.glLoadIdentity();
        Gl.glColor3f(1, 1, 1);
        Gl.glPushMatrix();
        Gl.glTranslated(0, 0, -6);
        Gl.glRotated(AlphaX, 1, 0, 0);
        Gl.glRotated(AlphaY, 0, 1, 0);

        Glut.glutWireCube(2);
        Gl.glColor3f(1, 0, 0);

        DrawAxes(0.5);
        Gl.glPopMatrix();
      }
      private void DrawAxes(double Length)
      {
        Gl.glColor3f(1, 0, 0);
        Gl.glBegin(Gl.GL_LINES);
           Gl.glVertex3d(0,0,0);
           Gl.glVertex3d(Length, 0, 0);
        Gl.glEnd();
        Gl.glColor3f(0, 1, 0);
        Gl.glBegin(Gl.GL_LINES);
           Gl.glVertex3d(0, 0, 0);
           Gl.glVertex3d(0, Length, 0);
        Gl.glEnd();
        Gl.glColor3f(0, 0, 1);
        Gl.glBegin(Gl.GL_LINES);
           Gl.glVertex3d(0, 0, 0);
           Gl.glVertex3d(0, 0, Length);
        Gl.glEnd();
      }

      private void AnT_DragDrop(object sender, DragEventArgs e)
      {
        
      }

      private void AnT_MouseDown_1(object sender, MouseEventArgs e)
      {
        x = e.X;
        y = e.Y;
        MouseIsDown = true;
      }

      private void AnT_MouseUp_1(object sender, MouseEventArgs e)
      {
        MouseIsDown = false;
      }

      private void AnT_MouseMove_1(object sender, MouseEventArgs e)
      {
        if (MouseIsDown)
        {
           AlphaX += Convert.ToDouble(x - e.X);
           AlphaY += Convert.ToDouble(y - e.Y);
           x = e.X;
           y = e.Y;
           Init();
           Draw();
        }
      }
   }
}