private bool getSelection(Canguro.Model.Model model, List<Canguro.Model.Item> selection)
{
foreach (Canguro.Model.Item item in model.JointList)
if (item != null && item.IsSelected)
selection.Add(item);
foreach (Canguro.Model.Item item in model.LineList)
if (item != null && item.IsSelected)
selection.Add(item);
foreach (Canguro.Model.Item item in model.AreaList)
if (item != null && item.IsSelected)
selection.Add(item);
return (selection.Count > 0);
}