internal GvMouseEventArgs(MouseEventArgs argsPar, XGraphViewer xGraphScrollerP)
 {
     args     = argsPar;
     position = args.GetPosition(xGraphScrollerP.MainPanel);
 }
 internal GvMouseEventArgs(MouseEventArgs argsPar, XGraphViewer xGraphScrollerP)
 {
     args = argsPar;
     position = args.GetPosition(xGraphScrollerP.MainPanel);
 }