constructor TTool.Create(AIndex, Ax, Ay: Integer; AShapeList: TShapeList; APaintBox: TPaintBox);
begin
case AIndex of
  1: FCurrentShape:=TPenLine.Create(Ax, Ay, APaintBox);
  2: FCurrentShape:=TLine.Create(Ax, Ay, APaintBox);
  3: FCurrentShape:=TRect.Create(Ax, Ay, APaintBox);
end;
AShapeList.AddShape(FCurrentShape);
end;