private void buttonExtVisitedClick(object sender, EventArgs e) { ISystem sys = textBoxSystemName.Text.Length > 0 ? discoveryform.history.FindSystem(textBoxSystemName.Text, discoveryform.galacticMapping) : new SystemClass("Unknown", numberBoxDoubleX.Value, numberBoxDoubleY.Value, numberBoxDoubleZ.Value); // find centre, i.e less 1 ly distance if (sys != null) { var list = HistoryList.FindSystemsWithinLy(discoveryform.history.EntryOrder, sys, numberBoxMinRadius.Value, numberBoxMaxRadius.Value, !checkBoxCustomCube.Checked); ReturnSystems((from x in list select new Tuple <ISystem, double>(x, x.Distance(sys))).ToList()); } else { ExtendedControls.MessageBoxTheme.Show(this.FindForm(), "Cannot find system ".Tx(this) + textBoxSystemName.Text, "Warning".Tx(), MessageBoxButtons.OK, MessageBoxIcon.Warning); } }