[Fix for MoveNubRenderer selection in the LineTool.]

Basically I fixed the line tool so that when you pick one of the 4 points on the line it will choose the one closest to the mouse. It currently does not do this for very small lines.

[Fix for MoveNubRenderer selection in the LineTool.]

I was getting annoyed when I was dealing with small lines, that it would select the wrong nub. So I changed the OnStylusDown method in the LineTool. Now it works perfectly.

Because instead of stopping at the first nub that passes the IsPointTouching method, it also checks all the nubs and picks the one closer to the mouse.

Here is the changed method:

        protected override void OnStylusDown(StylusEventArgs e)
       {
           bool callBase = false;
           if (!this.inCurveMode)
           {
               callBase = true;
           }
           else
           {
               PointF mousePt = new PointF(e.Fx, e.Fy);
               //start of change
               Single mindistance = Single.MaxValue;
               for (int i = 0; i < this.moveNubs.Length; ++i)
               {
                   if (this.moveNubs[i].IsPointTouching(Point.Truncate(mousePt), true))
                   {
                       PointF[] points = new PointF[]{this.moveNubs[i].Location};
                       this.moveNubs[i].Transform.TransformPoints(points);
                       Single distX = points[0].X - mousePt.X;
                       Single distY = points[0].Y - mousePt.Y;
                       Single distance = (Single)Math.Sqrt(distX * distX + distY * distY);
                       if (distance < mindistance)
                       {
                           mindistance = distance;
                           this.draggingNubIndex = i;
                           this.Cursor = this.handCursorMouseDown;
                           if (this.curveType == CurveType.NotDecided)
                           {
                               if (e.Button == MouseButtons.Right)
                               {
                                   this.curveType = CurveType.Bezier;
                               }
                               else
                               {
                                   this.curveType = CurveType.Spline;
                               }
                           }
                       }
                   }
               }
               //end of change
               if (this.draggingNubIndex == -1)
               {
                   callBase = true;
               }
               else
               {
                   for (int i = 0; i < this.moveNubs.Length; ++i)
                   {
                       this.moveNubs[i].Visible = false;
                   }
                   string helpText2 = PdnResources.GetString("LineTool.CurvingHelpText");
                   SetStatus(null, helpText2);
                   OnStylusMove(e);
               }
           }
           if (callBase)
           {
               base.OnStylusDown(e);
           }
       }

the original method is from 2.61