AForge.Controls.ManipulatorControl.ManipulatorControl_MouseDown C# (CSharp) Method

        private void ManipulatorControl_MouseDown( object sender, MouseEventArgs e )
        {
            if ( e.Button == MouseButtons.Left )
            {
                // get click point relatively to manipulation area's center
                int cX = e.X - areaMargin - areaRadius;
                int cY = e.Y - areaMargin - areaRadius;

                if ( isSquareLook )
                {
                    if (
                        ( cX <= areaRadius ) && ( cX >= -areaRadius ) &&
                        ( cY <= areaRadius ) && ( cY >= -areaRadius ) )
                    {
                        tracking = true;
                    }
                }
                else
                {
                    // check if the point is inside of manipulator
                    if ( Math.Sqrt( cX * cX + cY * cY ) <= areaRadius )
                    {
                        tracking = true;
                    }
                }

                if ( tracking )
                {
                    manipulatatorX = (float)  cX / areaRadius;
                    manipulatatorY = (float) -cY / areaRadius;

                    this.Capture = true;
                    this.Cursor = Cursors.Hand;

                    NotifyClients( );
                    // start timer, which is used to notify
                    // about manipulator's position change
                    ticksBeforeNotificiation = -1;
                    timer.Start( );
                }
            }
        }