function TPABounds2(TPA: TPointArray): TBox;
var
  h, i: Integer;
begin
  h := High(TPA);
  case (h > -1) of
    True:
    begin
      Result.X1 := TPA[0].X;
      Result.Y1 := TPA[0].Y;
      Result.X2 := TPA[0].X;
      Result.Y2 := TPA[0].Y
      if (h > 0) then
        for i := 1 to h do
        begin
          if (Result.X1 > TPA[i].X) then
            Result.X1 := TPA[i].X
          else
            if (Result.X2 < TPA[i].X) then
              Result.X2 := TPA[i].X;
          if (Result.Y1 > TPA[i].Y) then
            Result.Y1 := TPA[i].Y
          else
            if (Result.Y2 < TPA[i].Y) then
              Result.Y2 := TPA[i].Y;
        end;
    end;
    False:
    begin
      Result.X1 := 0;
      Result.Y1 := 0;
      Result.X2 := 0;
      Result.Y2 := 0;
    end;
  end;
end;

var
  TPA: TPointArray;

begin
  TPA := [Point(5, 10), Point(4, 4), Point(8, 12)];
  WriteLn(BoxToStr(TPABounds2(TPA)));
end.