procedure TMainForm.SelectObject(AIndex: integer);
{ Select Object with AIndex, AIndex is 0 based. }
var
  i: Integer;
  ihobj: Integer;
begin
  ImageEnVect1.UnSelAllObjects;
  for i := 0 to ImageEnVect1.ObjectsCount - 1 do
  begin
    ihobj := ImageEnVect1.GetObjFromIndex(i);
    if (not ImageEnVect1.IsSelObject(ihobj)) and (AIndex = ihobj) then
      ImageEnVect1.AddSelObject(ihobj);
  end;
  ImageEnVect1.Update;
end;