Main frame

Tower series returns the point index under a given XY position, for example the mouse cursor position when using the Series1 OnClick event:

procedure TForm1.Series1Click(Sender: TChartSeries;
  ValueIndex: Integer;
  Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  Label1.Caption:=' Clicked Tower :  ' + IntToStr(ValueIndex) + 
  '   X :  ' + FormatFloat('0.##',Series1.XValue[ValueIndex]) + 
  '   Y :  ' + FormatFloat('0.##',Series1.YValue[ValueIndex]) + 
  '   Z :  ' + FormatFloat('0.##',Series1.ZValue[ValueIndex]);
end;