Create a Box.

A box is defined by :

Its bottom left coordinates x1,y1
Its top right coordinates x2,y2

A box has line attributes (see TAttLine) and fill area attributes (see TAttFill).

Definition at line 24 of file TBox.h.

Public Types
enum	{ kCannotMove = BIT(12) }

Public Types inherited from TObject
enum	{ kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kBitMask = 0x00ffffff }

enum	{ kSingleKey = BIT(0), kOverwrite = BIT(1), kWriteDelete = BIT(2) }

enum	EStatusBits { kCanDelete = BIT(0), kMustCleanup = BIT(3), kObjInCanvas = BIT(3), kIsReferenced = BIT(4), kHasUUID = BIT(5), kCannotPick = BIT(6), kNoContextMenu = BIT(8), kInvalidObject = BIT(13) }

Public Member Functions
	TBox ()
	Box default constructor. More...

	TBox (Double_t x1, Double_t y1, Double_t x2, Double_t y2)
	Box standard constructor. More...

	TBox (const TBox &box)
	Box copy constructor. More...

virtual	~TBox ()
	Box destructor. More...

void	Copy (TObject &box) const
	Copy a Box. More...

virtual Int_t	DistancetoPrimitive (Int_t px, Int_t py)
	Compute distance from point px,py to a box. More...

virtual void	Draw (Option_t *option="")
	Draw this box with its current attributes. More...

virtual TBox *	DrawBox (Double_t x1, Double_t y1, Double_t x2, Double_t y2)
	Draw this box with new coordinates. More...

virtual void	ExecuteEvent (Int_t event, Int_t px, Int_t py)
	Execute action corresponding to one event. More...

virtual Rectangle_t	GetBBox ()
	Return the "bounding Box" of the Box. More...

virtual TPoint	GetBBoxCenter ()
	Return the center of the Box as TPoint in pixels. More...

Double_t	GetX1 () const

Double_t	GetX2 () const

Double_t	GetY1 () const

Double_t	GetY2 () const

virtual void	HideToolTip (Int_t event)
	Hide tool tip depending on the event type. More...

Bool_t	IsBeingResized () const

virtual Int_t	IsInside (Double_t x, Double_t y) const
	Function which returns 1 if point x,y lies inside the box, 0 otherwise. More...

virtual void	ls (Option_t *option="") const
	List this box with its attributes. More...

TBox &	operator= (const TBox &)
	Assignment operator. More...

virtual void	Paint (Option_t *option="")
	Paint this box with its current attributes. More...

virtual void	PaintBox (Double_t x1, Double_t y1, Double_t x2, Double_t y2, Option_t *option="")
	Draw this box with new coordinates. More...

virtual void	Print (Option_t *option="") const
	Dump this box with its attributes. More...

virtual void	SavePrimitive (std::ostream &out, Option_t *option="")
	Save primitive as a C++ statement(s) on output stream out. More...

virtual void	SetBBoxCenter (const TPoint &p)
	Set center of the Box. More...

virtual void	SetBBoxCenterX (const Int_t x)
	Set X coordinate of the center of the Box. More...

virtual void	SetBBoxCenterY (const Int_t y)
	Set Y coordinate of the center of the Box. More...

virtual void	SetBBoxX1 (const Int_t x)
	Set left hand side of BoundingBox to a value (resize in x direction on left) More...

virtual void	SetBBoxX2 (const Int_t x)
	Set right hand side of BoundingBox to a value (resize in x direction on right) More...

virtual void	SetBBoxY1 (const Int_t y)
	Set top of BoundingBox to a value (resize in y direction on top) More...

virtual void	SetBBoxY2 (const Int_t y)
	Set bottom of BoundingBox to a value (resize in y direction on bottom) More...

virtual void	SetToolTipText (const char *text, Long_t delayms=1000)
	Set tool tip text associated with this box. More...

virtual void	SetX1 (Double_t x1)

virtual void	SetX2 (Double_t x2)

virtual void	SetY1 (Double_t y1)

virtual void	SetY2 (Double_t y2)

Public Member Functions inherited from TObject
	TObject ()
	TObject constructor. More...

	TObject (const TObject &object)
	TObject copy ctor. More...

virtual	~TObject ()
	TObject destructor. More...

void	AbstractMethod (const char *method) const
	Use this method to implement an "abstract" method that you don't want to leave purely abstract. More...

virtual void	AppendPad (Option_t *option="")
	Append graphics object to current pad. More...

virtual void	Browse (TBrowser *b)
	Browse object. May be overridden for another default action. More...

virtual const char *	ClassName () const
	Returns name of class to which the object belongs. More...

virtual void	Clear (Option_t *="")

virtual TObject *	Clone (const char *newname="") const
	Make a clone of an object using the Streamer facility. More...

virtual Int_t	Compare (const TObject *obj) const
	Compare abstract method. More...

virtual void	Delete (Option_t *option="")
	Delete this object. More...

virtual void	DrawClass () const
	Draw class inheritance tree of the class to which this object belongs. More...

virtual TObject *	DrawClone (Option_t *option="") const
	Draw a clone of this object in the current selected pad for instance with: `gROOT->SetSelectedPad(gPad)`. More...

virtual void	Dump () const
	Dump contents of object on stdout. More...

virtual void	Error (const char method, const char msgfmt,...) const
	Issue error message. More...

virtual void	Execute (const char method, const char params, Int_t *error=0)
	Execute method on this object with the given parameter string, e.g. More...

virtual void	Execute (TMethod method, TObjArray params, Int_t *error=0)
	Execute method on this object with parameters stored in the TObjArray. More...

virtual void	Fatal (const char method, const char msgfmt,...) const
	Issue fatal error message. More...

virtual TObject *	FindObject (const char *name) const
	Must be redefined in derived classes. More...

virtual TObject *	FindObject (const TObject *obj) const
	Must be redefined in derived classes. More...

virtual Option_t *	GetDrawOption () const
	Get option used by the graphics system to draw this object. More...

virtual const char *	GetIconName () const
	Returns mime type name of object. More...

virtual const char *	GetName () const
	Returns name of object. More...

virtual char *	GetObjectInfo (Int_t px, Int_t py) const
	Returns string containing info about the object at position (px,py). More...

virtual Option_t *	GetOption () const

virtual const char *	GetTitle () const
	Returns title of object. More...

virtual UInt_t	GetUniqueID () const
	Return the unique object id. More...

virtual Bool_t	HandleTimer (TTimer *timer)
	Execute action in response of a timer timing out. More...

virtual ULong_t	Hash () const
	Return hash value for this object. More...

virtual void	Info (const char method, const char msgfmt,...) const
	Issue info message. More...

virtual Bool_t	InheritsFrom (const char *classname) const
	Returns kTRUE if object inherits from class "classname". More...

virtual Bool_t	InheritsFrom (const TClass *cl) const
	Returns kTRUE if object inherits from TClass cl. More...

virtual void	Inspect () const
	Dump contents of this object in a graphics canvas. More...

void	InvertBit (UInt_t f)

virtual Bool_t	IsEqual (const TObject *obj) const
	Default equal comparison (objects are equal if they have the same address in memory). More...

virtual Bool_t	IsFolder () const
	Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More...

Bool_t	IsOnHeap () const

virtual Bool_t	IsSortable () const

Bool_t	IsZombie () const

void	MayNotUse (const char *method) const
	Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary). More...

virtual Bool_t	Notify ()
	This method must be overridden to handle object notification. More...

void	Obsolete (const char method, const char asOfVers, const char *removedFromVers) const
	Use this method to declare a method obsolete. More...

void	operator delete (void *ptr)
	Operator delete. More...

void	operator delete[] (void *ptr)
	Operator delete []. More...

void *	operator new (size_t sz)

void *	operator new (size_t sz, void *vp)

void *	operator new[] (size_t sz)

void *	operator new[] (size_t sz, void *vp)

TObject &	operator= (const TObject &rhs)
	TObject assignment operator. More...

virtual void	Pop ()
	Pop on object drawn in a pad to the top of the display list. More...

virtual Int_t	Read (const char *name)
	Read contents of object with specified name from the current directory. More...

virtual void	RecursiveRemove (TObject *obj)
	Recursively remove this object from a list. More...

void	ResetBit (UInt_t f)

virtual void	SaveAs (const char filename="", Option_t option="") const
	Save this object in the file specified by filename. More...

void	SetBit (UInt_t f, Bool_t set)
	Set or unset the user status bits as specified in f. More...

void	SetBit (UInt_t f)

virtual void	SetDrawOption (Option_t *option="")
	Set drawing option for object. More...

virtual void	SetUniqueID (UInt_t uid)
	Set the unique object id. More...

virtual void	SysError (const char method, const char msgfmt,...) const
	Issue system error message. More...

Bool_t	TestBit (UInt_t f) const

Int_t	TestBits (UInt_t f) const

virtual void	UseCurrentStyle ()
	Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked. More...

virtual void	Warning (const char method, const char msgfmt,...) const
	Issue warning message. More...

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
	Write this object to the current directory. More...

virtual Int_t	Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
	Write this object to the current directory. More...

Public Member Functions inherited from TAttLine
	TAttLine ()
	AttLine default constructor. More...

	TAttLine (Color_t lcolor, Style_t lstyle, Width_t lwidth)
	AttLine normal constructor. More...

virtual	~TAttLine ()
	AttLine destructor. More...

void	Copy (TAttLine &attline) const
	Copy this line attributes to a new TAttLine. More...

Int_t	DistancetoLine (Int_t px, Int_t py, Double_t xp1, Double_t yp1, Double_t xp2, Double_t yp2)
	Compute distance from point px,py to a line. More...

virtual Color_t	GetLineColor () const
	Return the line color. More...

virtual Style_t	GetLineStyle () const
	Return the line style. More...

virtual Width_t	GetLineWidth () const
	Return the line width. More...

virtual void	Modify ()
	Change current line attributes if necessary. More...

virtual void	ResetAttLine (Option_t *option="")
	Reset this line attributes to default values. More...

virtual void	SaveLineAttributes (std::ostream &out, const char *name, Int_t coldef=1, Int_t stydef=1, Int_t widdef=1)
	Save line attributes as C++ statement(s) on output stream out. More...

virtual void	SetLineAttributes ()
	Invoke the DialogCanvas Line attributes. More...

virtual void	SetLineColor (Color_t lcolor)
	Set the line color. More...

virtual void	SetLineColorAlpha (Color_t lcolor, Float_t lalpha)
	Set a transparent line color. More...

virtual void	SetLineStyle (Style_t lstyle)
	Set the line style. More...

virtual void	SetLineWidth (Width_t lwidth)
	Set the line width. More...

Public Member Functions inherited from TAttFill
	TAttFill ()
	AttFill default constructor. More...

	TAttFill (Color_t fcolor, Style_t fstyle)
	AttFill normal constructor. More...

virtual	~TAttFill ()
	AttFill destructor. More...

void	Copy (TAttFill &attfill) const
	Copy this fill attributes to a new TAttFill. More...

virtual Color_t	GetFillColor () const
	Return the fill area color. More...

virtual Style_t	GetFillStyle () const
	Return the fill area style. More...

virtual Bool_t	IsTransparent () const

virtual void	Modify ()
	Change current fill area attributes if necessary. More...

virtual void	ResetAttFill (Option_t *option="")
	Reset this fill attributes to default values. More...

virtual void	SaveFillAttributes (std::ostream &out, const char *name, Int_t coldef=1, Int_t stydef=1001)
	Save fill attributes as C++ statement(s) on output stream out. More...

virtual void	SetFillAttributes ()
	Invoke the DialogCanvas Fill attributes. More...

virtual void	SetFillColor (Color_t fcolor)
	Set the fill area color. More...

virtual void	SetFillColorAlpha (Color_t fcolor, Float_t falpha)
	Set a transparent fill color. More...

virtual void	SetFillStyle (Style_t fstyle)
	Set the fill area style. More...

Public Member Functions inherited from TAttBBox2D
virtual	~TAttBBox2D ()

Protected Attributes
Bool_t	fResizing
	! True if box is being resized More...

Double_t	fX1
	X of 1st point. More...

Double_t	fX2
	X of 2nd point. More...

Double_t	fY1
	Y of 1st point. More...

Double_t	fY2
	Y of 2nd point. More...

Protected Attributes inherited from TAttLine
Color_t	fLineColor
	Line color. More...

Style_t	fLineStyle
	Line style. More...

Width_t	fLineWidth
	Line width. More...

Protected Attributes inherited from TAttFill
Color_t	fFillColor
	Fill area color. More...

Style_t	fFillStyle
	Fill area style. More...

Private Attributes
TObject *	fTip
	! tool tip associated with box More...

Additional Inherited Members
Static Public Member Functions inherited from TObject
static Long_t	GetDtorOnly ()
	Return destructor only flag. More...

static Bool_t	GetObjectStat ()
	Get status of object stat flag. More...

static void	SetDtorOnly (void *obj)
	Set destructor only flag. More...

static void	SetObjectStat (Bool_t stat)
	Turn on/off tracking of objects in the TObjectTable. More...

Protected Member Functions inherited from TObject
virtual void	DoError (int level, const char location, const char fmt, va_list va) const
	Interface to ErrorHandler (protected). More...

void	MakeZombie ()

#include <TBox.h>

Inheritance diagram for TBox:

[legend]

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

Enumerator
kCannotMove

Definition at line 38 of file TBox.h.

Constructor & Destructor Documentation

◆ TBox() [1/3]

TBox::TBox ( )

Box default constructor.

Definition at line 41 of file TBox.cxx.

◆ TBox() [2/3]

TBox::TBox	(	Double_t	x1,
		Double_t	y1,
		Double_t	x2,
		Double_t	y2
	)

Box standard constructor.

Definition at line 54 of file TBox.cxx.

◆ TBox() [3/3]

TBox::TBox ( const TBox & box )

Box copy constructor.

Definition at line 79 of file TBox.cxx.

◆ ~TBox()

TBox::~TBox ( )

virtual

Box destructor.

Definition at line 68 of file TBox.cxx.

Member Function Documentation

◆ Copy()

void TBox::Copy ( TObject & box ) const

virtual

Copy a Box.

Reimplemented from TObject.

Reimplemented in TPave, TPaletteAxis, TLegend, TWbox, TPaveLabel, and TFrame.

Definition at line 111 of file TBox.cxx.

◆ DistancetoPrimitive()

Int_t TBox::DistancetoPrimitive	(	Int_t	px,
		Int_t	py
	)

virtual

Compute distance from point px,py to a box.

Compute the closest distance of approach from point px,py to the edges of this box. The distance is computed in pixels units.

In case of a filled box the distance returned is 0 if the point (px,py) is inside the box, and is huge if the point is outside.

Reimplemented from TObject.

Reimplemented in TPaletteAxis, TPave, and TDiamond.

Definition at line 134 of file TBox.cxx.

◆ Draw()

void TBox::Draw ( Option_t * option = "" )

virtual

Draw this box with its current attributes.

if the box has no fill style (ie fill style=0), the box contour is drawn if the box has a fill style, the box contour is not drawn by default. to force the contour to be drawn, specify option "l"

Reimplemented from TObject.

Reimplemented in TPave, TPaveText, TLegend, TWbox, TPaveLabel, TDiamond, TPavesText, and TFrame.

Definition at line 180 of file TBox.cxx.

◆ DrawBox()

TBox * TBox::DrawBox	(	Double_t	x1,
		Double_t	y1,
		Double_t	x2,
		Double_t	y2
	)

virtual

Draw this box with new coordinates.

Definition at line 189 of file TBox.cxx.

◆ ExecuteEvent()

void TBox::ExecuteEvent	(	Int_t	event,
		Int_t	px,
		Int_t	py
	)

virtual

Execute action corresponding to one event.

This member function is called when a BOX/WBOX/PAD object is clicked.

If the mouse is clicked in one of the 4 corners of the box (pA,pB,pC,pD) the box is resized with the rubber rectangle.

If the mouse is clicked inside the box, the box is moved.

If the mouse is clicked on the 4 edges (pL,pR,pTop,pBot), the box is rescaled parallel to this edge (same as Motif window manager).

Note that this function is duplicated on purpose by TPad::ExecuteEvent. If somebody modifies this function, may be similar changes should also be applied to TPad::ExecuteEvent.

Reimplemented from TObject.

Reimplemented in TPave, TPaletteAxis, TWbox, TSliderBox, TDiamond, and TFrame.

Definition at line 216 of file TBox.cxx.

◆ GetBBox()

Rectangle_t TBox::GetBBox ( )

virtual

Return the "bounding Box" of the Box.

Implements TAttBBox2D.

Definition at line 727 of file TBox.cxx.

◆ GetBBoxCenter()

TPoint TBox::GetBBoxCenter ( )

virtual

Return the center of the Box as TPoint in pixels.

Implements TAttBBox2D.

Definition at line 751 of file TBox.cxx.

◆ GetX1()

Double_t TBox::GetX1 ( ) const

inline

Definition at line 52 of file TBox.h.

◆ GetX2()

Double_t TBox::GetX2 ( ) const

inline

Definition at line 53 of file TBox.h.

◆ GetY1()

Double_t TBox::GetY1 ( ) const

inline

Definition at line 54 of file TBox.h.

◆ GetY2()

Double_t TBox::GetY2 ( ) const

inline

Definition at line 55 of file TBox.h.

◆ HideToolTip()

void TBox::HideToolTip ( Int_t event )

virtual

Hide tool tip depending on the event type.

Typically tool tips are hidden when event is not a kMouseEnter and not a kMouseMotion event.

Definition at line 591 of file TBox.cxx.

◆ IsBeingResized()

Bool_t TBox::IsBeingResized ( ) const

inline

Definition at line 51 of file TBox.h.

◆ IsInside()

Int_t TBox::IsInside	(	Double_t	x,
		Double_t	y
	)		const

virtual

Function which returns 1 if point x,y lies inside the box, 0 otherwise.

Definition at line 600 of file TBox.cxx.

◆ ls()

void TBox::ls ( Option_t * option = "" ) const

virtual

List this box with its attributes.

Reimplemented from TObject.

Reimplemented in TPave.

Definition at line 610 of file TBox.cxx.

◆ operator=()

TBox & TBox::operator= ( const TBox & b )

Assignment operator.

Definition at line 92 of file TBox.cxx.

◆ Paint()

void TBox::Paint ( Option_t * option = "" )

virtual

Paint this box with its current attributes.

Reimplemented from TObject.

Reimplemented in TPave, TLegend, TPaveText, TPaletteAxis, TWbox, TPaveStats, TPaveLabel, TDiamond, TPavesText, and TFrame.

Definition at line 619 of file TBox.cxx.

◆ PaintBox()

void TBox::PaintBox	(	Double_t	x1,
		Double_t	y1,
		Double_t	x2,
		Double_t	y2,
		Option_t *	option = `""`
	)

virtual

Draw this box with new coordinates.

Definition at line 627 of file TBox.cxx.

◆ Print()

void TBox::Print ( Option_t * option = "" ) const

virtual

Dump this box with its attributes.

Reimplemented from TObject.

Reimplemented in TPave, TLegend, and TPaveText.

Definition at line 645 of file TBox.cxx.

◆ SavePrimitive()

void TBox::SavePrimitive	(	std::ostream &	out,
		Option_t *	option = `""`
	)

virtual

Save primitive as a C++ statement(s) on output stream out.

Reimplemented from TObject.

Reimplemented in TPave, TLegend, TPaveText, TPaletteAxis, TWbox, TPaveStats, TPaveLabel, TSliderBox, TPaveClass, TDiamond, TFrame, and TPavesText.

Definition at line 659 of file TBox.cxx.

◆ SetBBoxCenter()

void TBox::SetBBoxCenter ( const TPoint & p )

virtual

Set center of the Box.

Implements TAttBBox2D.

Definition at line 762 of file TBox.cxx.

◆ SetBBoxCenterX()

void TBox::SetBBoxCenterX ( const Int_t x )

virtual

Set X coordinate of the center of the Box.

Implements TAttBBox2D.

Definition at line 787 of file TBox.cxx.

◆ SetBBoxCenterY()

void TBox::SetBBoxCenterY ( const Int_t y )

virtual

Set Y coordinate of the center of the Box.

Implements TAttBBox2D.

Definition at line 803 of file TBox.cxx.

◆ SetBBoxX1()

void TBox::SetBBoxX1 ( const Int_t x )

virtual

Set left hand side of BoundingBox to a value (resize in x direction on left)

Implements TAttBBox2D.

Definition at line 820 of file TBox.cxx.

◆ SetBBoxX2()

void TBox::SetBBoxX2 ( const Int_t x )

virtual

Set right hand side of BoundingBox to a value (resize in x direction on right)

Implements TAttBBox2D.

Definition at line 829 of file TBox.cxx.

◆ SetBBoxY1()

void TBox::SetBBoxY1 ( const Int_t y )

virtual

Set top of BoundingBox to a value (resize in y direction on top)

Implements TAttBBox2D.

Definition at line 837 of file TBox.cxx.

◆ SetBBoxY2()

void TBox::SetBBoxY2 ( const Int_t y )

virtual

Set bottom of BoundingBox to a value (resize in y direction on bottom)

Implements TAttBBox2D.

Definition at line 846 of file TBox.cxx.

◆ SetToolTipText()

void TBox::SetToolTipText	(	const char *	text,
		Long_t	delayms = `1000`
	)

virtual

Set tool tip text associated with this box.

The delay is in milliseconds (minimum 250). To remove tool tip call method with text = 0.

Definition at line 679 of file TBox.cxx.

◆ SetX1()

virtual void TBox::SetX1 ( Double_t x1 )

inlinevirtual

Reimplemented in TPave.

Definition at line 63 of file TBox.h.

◆ SetX2()

virtual void TBox::SetX2 ( Double_t x2 )

inlinevirtual

Reimplemented in TPave.

Definition at line 64 of file TBox.h.

◆ SetY1()

virtual void TBox::SetY1 ( Double_t y1 )

inlinevirtual

Reimplemented in TPave.

Definition at line 65 of file TBox.h.

◆ SetY2()

virtual void TBox::SetY2 ( Double_t y2 )

inlinevirtual

Reimplemented in TPave.

Definition at line 66 of file TBox.h.

Member Data Documentation

◆ fResizing

Bool_t TBox::fResizing

protected

! True if box is being resized

Definition at line 34 of file TBox.h.

◆ fTip

TObject* TBox::fTip

private

! tool tip associated with box

Definition at line 27 of file TBox.h.

◆ fX1

Double_t TBox::fX1

protected

X of 1st point.

Definition at line 30 of file TBox.h.

◆ fX2

Double_t TBox::fX2

protected

X of 2nd point.

Definition at line 32 of file TBox.h.

◆ fY1

Double_t TBox::fY1

protected

Y of 1st point.

Definition at line 31 of file TBox.h.

◆ fY2

Double_t TBox::fY2

protected

Y of 2nd point.

Definition at line 33 of file TBox.h.

The documentation for this class was generated from the following files:

graf2d/graf/inc/TBox.h
graf2d/graf/src/TBox.cxx

Public Types

Public Member Functions

Protected Attributes

Private Attributes

Additional Inherited Members

Member Enumeration Documentation

◆ anonymous enum

Constructor & Destructor Documentation

◆ TBox() [1/3]

◆ TBox() [2/3]

◆ TBox() [3/3]

◆ ~TBox()

Member Function Documentation

◆ Copy()

◆ DistancetoPrimitive()

◆ Draw()

◆ DrawBox()

◆ ExecuteEvent()

◆ GetBBox()

◆ GetBBoxCenter()

◆ GetX1()

◆ GetX2()

◆ GetY1()

◆ GetY2()

◆ HideToolTip()

◆ IsBeingResized()

◆ IsInside()

◆ ls()

◆ operator=()

◆ Paint()

◆ PaintBox()

◆ Print()

◆ SavePrimitive()

◆ SetBBoxCenter()

◆ SetBBoxCenterX()

◆ SetBBoxCenterY()

◆ SetBBoxX1()

◆ SetBBoxX2()

◆ SetBBoxY1()

◆ SetBBoxY2()

◆ SetToolTipText()

◆ SetX1()

◆ SetX2()

◆ SetY1()

◆ SetY2()

Member Data Documentation

◆ fResizing

◆ fTip

◆ fX1

◆ fX2

◆ fY1

◆ fY2