BuildingCoder.CmdPickPoint3d.PickPointsForArea C# (CSharp) Метод

        public void PickPointsForArea(
            UIDocument uidoc)
        {
            Document doc = uidoc.Document;
              View view = doc.ActiveView;

              #region COMPLICATED_UNRELIABLE_DOES_NOT_WORK
            #if COMPLICATED_UNRELIABLE_DOES_NOT_WORK

            using( Transaction t = new Transaction( doc ) )
            {
              t.Start( "Set Work Plane" );

              Plane plane = new Plane(
            view.ViewDirection,
            view.Origin );

              //SketchPlane sp = doc.Create.NewSketchPlane( plane );

              SketchPlane sp = SketchPlane.Create( doc, plane );

              view.SketchPlane = sp;
              view.ShowActiveWorkPlane();

              t.Commit();
            }

            double differenceX;
            double differenceY;
            double differenceZ;
            double area;

            XYZ pt1 = uidoc.Selection.PickPoint();
            XYZ pt2 = uidoc.Selection.PickPoint();

            double pt1x = pt1.X;
            double pt1y = pt1.Y;
            double pt1z = pt1.Z;

            double pt2x = pt2.X;
            double pt2y = pt2.Y;
            double pt2z = pt2.Z;

            bool b;
            int caseSwitch = 0;

            if( b = ( pt1z == pt2z ) )
            { caseSwitch = 1; }

            if( b = ( pt1y == pt2y ) )
            { caseSwitch = 2; }

            if( b = ( pt1x == pt2x ) )
            { caseSwitch = 3; }

            switch( caseSwitch )
            {
              case 1:
            differenceX = pt2x - pt1x;
            differenceY = pt1y - pt2y;
            area = differenceX * differenceY;
            break;

              case 2:
            differenceX = pt2x - pt1x;
            differenceZ = pt1z - pt2z;
            area = differenceX * differenceZ;
            break;

              default:
            differenceY = pt2y - pt1y;
            differenceZ = pt1z - pt2z;
            area = differenceY * differenceZ;
            break;
            }
            #endif // COMPLICATED_UNRELIABLE_DOES_NOT_WORK
              #endregion // COMPLICATED_UNRELIABLE_DOES_NOT_WORK

              XYZ p1, p2;

              try
              {
            p1 = uidoc.Selection.PickPoint(
              "Please pick first point for area" );

            p2 = uidoc.Selection.PickPoint(
              "Please pick second point for area" );
              }
              catch( Autodesk.Revit.Exceptions.OperationCanceledException )
              {
            return;
              }

              Plane plane = view.SketchPlane.GetPlane();

              UV q1 = plane.ProjectInto( p1 );
              UV q2 = plane.ProjectInto( p2 );
              UV d = q2 - q1;

              double area = d.U * d.V;

              area = Math.Round( area, 2 );

              if( area < 0 )
              {
            area = area * ( -1 );
              }

              TaskDialog.Show( "Area", area.ToString() );
        }