How to get bounds rect of the shapes??

How to get bounds rect of the shapes??

https://drive.google.com/file/d/0BwdfodaqQm4pLXpNRGNkM2tyMGM/view?usp=sharing

After some tries , I get it work:

procedure TForm1.Button1Click(Sender: TObject);
begin
with TRectangle.Create(FViewBox) do
begin
Parent := FViewBox;
BoundsRect := GetBoundsRect(FViewBox);
Opacity := 0.7;
end;
end;

function TForm1.GetBoundsRect(TPathContainer: TLayout): TRectF;
var
LControl: TControl;
LPath: TPath;
LLeft, LRight, LTop, LBottom: Single;
LLeftAssigned, LRightAssigned, LTopAssigned, LBottomAssigned: Boolean;
begin
LLeftAssigned := False;
LRightAssigned := False;
LTopAssigned := False;
LBottomAssigned := False;
// Get Bounds Rect of All Paths
for LControl in TPathContainer.Controls do
begin
if LControl is TPath then
begin
LPath := LControl as TPath;
if not LLeftAssigned then
begin
LLeft := LPath.Data.GetBounds.Left;
LLeftAssigned := True;
end
else
LLeft := Min(LLeft, LPath.Data.GetBounds.Left);
if not LRightAssigned then
begin
LRight := LPath.Data.GetBounds.Right;
LRightAssigned := True;
end
else
LRight := Max(LRight, LPath.Data.GetBounds.Right);
if not LTopAssigned then
begin
LTop := LPath.Data.GetBounds.Top;
LTopAssigned := True;
end
else
LTop := Min(LTop, LPath.Data.GetBounds.Top);
if not LBottomAssigned then
begin
LBottom := LPath.Data.GetBounds.Bottom;
LBottomAssigned := True;
end
else
LBottom := Max(LBottom, LPath.Data.GetBounds.Bottom);
end;
end;

Result := TRectF.Create(LLeft, LTop, LRight, LBottom);

Result.Fit(FVectorContainer.BoundsRect);
OffsetRect(Result, -FVectorContainer.Position.X, -FVectorContainer.Position.Y);

end;