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TImagePalette Class Reference

A class to define a conversion from pixel values to pixel color.

A Palette is defined by some anchor points. Each anchor point has a value between 0 and 1 and a color. An image has to be normalized and the values between the anchor points are interpolated. All member variables are public and can be directly manipulated. In most cases the default operator will be used to create a TImagePalette. In this case the member arrays have to be allocated by an application and will be deleted in the destructor of this class.

We provide few predefined palettes:

  • gHistImagePalette - palette used in TH2::Draw("col")
  • gWebImagePalette The web palette is a set of 216 colors that will not dither or shift on PCs or Macs. Browsers use this built-in palette when they need to render colors on monitors with only 256 colors (also called 8-bit color monitors). The 6x6x6 web palette provides very quick color index lookup and can be used for good quality conversion of images into 2-D histograms.
  • TImagePalette(Int_t ncolors, Int_t *colors) if ncolors <= 0 a default palette (see below) of 50 colors is defined.

if ncolors == 1 && colors == 0, then a Rainbow Palette is created.

if ncolors > 50 and colors=0, the DeepSea palette is used. (see TStyle::CreateGradientColorTable for more details)

if ncolors > 0 and colors = 0, the default palette is used with a maximum of ncolors.

The default palette defines:

  • index 0->9 : grey colors from light to dark grey
  • index 10->19 : "brown" colors
  • index 20->29 : "blueish" colors
  • index 30->39 : "redish" colors
  • index 40->49 : basic colors

Definition at line 33 of file TAttImage.h.

Public Member Functions

 TImagePalette ()
 Default constructor, sets all pointers to 0.
 
 TImagePalette (const TImagePalette &palette)
 Copy constructor.
 
 TImagePalette (Int_t ncolors, Int_t *colors)
 Creates palette in the same way as TStyle::SetPalette.
 
 TImagePalette (UInt_t numPoints)
 Constructor for a palette with numPoints anchor points.
 
virtual ~TImagePalette ()
 Destructor.
 
virtual Int_t FindColor (UShort_t r, UShort_t g, UShort_t b)
 Returns an index of the closest color.
 
virtual Int_tGetRootColors ()
 Returns a list of ROOT colors.
 
TImagePaletteoperator= (const TImagePalette &palette)
 Assignment operator.
 
- Public Member Functions inherited from TObject
 TObject ()
 TObject constructor.
 
 TObject (const TObject &object)
 TObject copy ctor.
 
virtual ~TObject ()
 TObject destructor.
 
void AbstractMethod (const char *method) const
 Use this method to implement an "abstract" method that you don't want to leave purely abstract.
 
virtual void AppendPad (Option_t *option="")
 Append graphics object to current pad.
 
virtual void Browse (TBrowser *b)
 Browse object. May be overridden for another default action.
 
ULong_t CheckedHash ()
 Check and record whether this class has a consistent Hash/RecursiveRemove setup (*) and then return the regular Hash value for this object.
 
virtual const char * ClassName () const
 Returns name of class to which the object belongs.
 
virtual void Clear (Option_t *="")
 
virtual TObjectClone (const char *newname="") const
 Make a clone of an object using the Streamer facility.
 
virtual Int_t Compare (const TObject *obj) const
 Compare abstract method.
 
virtual void Copy (TObject &object) const
 Copy this to obj.
 
virtual void Delete (Option_t *option="")
 Delete this object.
 
virtual Int_t DistancetoPrimitive (Int_t px, Int_t py)
 Computes distance from point (px,py) to the object.
 
virtual void Draw (Option_t *option="")
 Default Draw method for all objects.
 
virtual void DrawClass () const
 Draw class inheritance tree of the class to which this object belongs.
 
virtual TObjectDrawClone (Option_t *option="") const
 Draw a clone of this object in the current selected pad for instance with: gROOT->SetSelectedPad(gPad).
 
virtual void Dump () const
 Dump contents of object on stdout.
 
virtual void Error (const char *method, const char *msgfmt,...) const
 Issue error message.
 
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.
 
virtual void Execute (TMethod *method, TObjArray *params, Int_t *error=0)
 Execute method on this object with parameters stored in the TObjArray.
 
virtual void ExecuteEvent (Int_t event, Int_t px, Int_t py)
 Execute action corresponding to an event at (px,py).
 
virtual void Fatal (const char *method, const char *msgfmt,...) const
 Issue fatal error message.
 
virtual TObjectFindObject (const char *name) const
 Must be redefined in derived classes.
 
virtual TObjectFindObject (const TObject *obj) const
 Must be redefined in derived classes.
 
virtual Option_tGetDrawOption () const
 Get option used by the graphics system to draw this object.
 
virtual const char * GetIconName () const
 Returns mime type name of object.
 
virtual const char * GetName () const
 Returns name of object.
 
virtual char * GetObjectInfo (Int_t px, Int_t py) const
 Returns string containing info about the object at position (px,py).
 
virtual Option_tGetOption () const
 
virtual const char * GetTitle () const
 Returns title of object.
 
virtual UInt_t GetUniqueID () const
 Return the unique object id.
 
virtual Bool_t HandleTimer (TTimer *timer)
 Execute action in response of a timer timing out.
 
virtual ULong_t Hash () const
 Return hash value for this object.
 
Bool_t HasInconsistentHash () const
 Return true is the type of this object is known to have an inconsistent setup for Hash and RecursiveRemove (i.e.
 
virtual void Info (const char *method, const char *msgfmt,...) const
 Issue info message.
 
virtual Bool_t InheritsFrom (const char *classname) const
 Returns kTRUE if object inherits from class "classname".
 
virtual Bool_t InheritsFrom (const TClass *cl) const
 Returns kTRUE if object inherits from TClass cl.
 
virtual void Inspect () const
 Dump contents of this object in a graphics canvas.
 
void InvertBit (UInt_t f)
 
Bool_t IsDestructed () const
 IsDestructed.
 
virtual Bool_t IsEqual (const TObject *obj) const
 Default equal comparison (objects are equal if they have the same address in memory).
 
virtual Bool_t IsFolder () const
 Returns kTRUE in case object contains browsable objects (like containers or lists of other objects).
 
R__ALWAYS_INLINE Bool_t IsOnHeap () const
 
virtual Bool_t IsSortable () const
 
R__ALWAYS_INLINE Bool_t IsZombie () const
 
virtual void ls (Option_t *option="") const
 The ls function lists the contents of a class on stdout.
 
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).
 
virtual Bool_t Notify ()
 This method must be overridden to handle object notification.
 
void Obsolete (const char *method, const char *asOfVers, const char *removedFromVers) const
 Use this method to declare a method obsolete.
 
void operator delete (void *ptr)
 Operator delete.
 
void operator delete[] (void *ptr)
 Operator delete [].
 
voidoperator new (size_t sz)
 
voidoperator new (size_t sz, void *vp)
 
voidoperator new[] (size_t sz)
 
voidoperator new[] (size_t sz, void *vp)
 
TObjectoperator= (const TObject &rhs)
 TObject assignment operator.
 
virtual void Paint (Option_t *option="")
 This method must be overridden if a class wants to paint itself.
 
virtual void Pop ()
 Pop on object drawn in a pad to the top of the display list.
 
virtual void Print (Option_t *option="") const
 This method must be overridden when a class wants to print itself.
 
virtual Int_t Read (const char *name)
 Read contents of object with specified name from the current directory.
 
virtual void RecursiveRemove (TObject *obj)
 Recursively remove this object from a list.
 
void ResetBit (UInt_t f)
 
virtual void SaveAs (const char *filename="", Option_t *option="") const
 Save this object in the file specified by filename.
 
virtual void SavePrimitive (std::ostream &out, Option_t *option="")
 Save a primitive as a C++ statement(s) on output stream "out".
 
void SetBit (UInt_t f)
 
void SetBit (UInt_t f, Bool_t set)
 Set or unset the user status bits as specified in f.
 
virtual void SetDrawOption (Option_t *option="")
 Set drawing option for object.
 
virtual void SetUniqueID (UInt_t uid)
 Set the unique object id.
 
virtual void SysError (const char *method, const char *msgfmt,...) const
 Issue system error message.
 
R__ALWAYS_INLINE 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.
 
virtual void Warning (const char *method, const char *msgfmt,...) const
 Issue warning message.
 
virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
 Write this object to the current directory.
 
virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
 Write this object to the current directory.
 

Static Public Member Functions

static TImagePaletteCreate (Option_t *opts)
 Factory method to creates an image palette of a specific typ.
 
static TImagePaletteCreateCOLPalette (Int_t nContours)
 Factory method to creates an image palette for histogram plotting.
 
- Static Public Member Functions inherited from TObject
static Longptr_t GetDtorOnly ()
 Return destructor only flag.
 
static Bool_t GetObjectStat ()
 Get status of object stat flag.
 
static void SetDtorOnly (void *obj)
 Set destructor only flag.
 
static void SetObjectStat (Bool_t stat)
 Turn on/off tracking of objects in the TObjectTable.
 

Public Attributes

UShort_tfColorAlpha
 [fNumPoints] alpha at each anchor point
 
UShort_tfColorBlue
 [fNumPoints] blue color at each anchor point
 
UShort_tfColorGreen
 [fNumPoints] green color at each anchor point
 
UShort_tfColorRed
 [fNumPoints] red color at each anchor point
 
UInt_t fNumPoints
 number of anchor points
 
Double_tfPoints
 [fNumPoints] value of each anchor point [0..1]
 

Additional Inherited Members

- Public Types inherited from TObject
enum  {
  kIsOnHeap = 0x01000000 , kNotDeleted = 0x02000000 , kZombie = 0x04000000 , kInconsistent = 0x08000000 ,
  kBitMask = 0x00ffffff
}
 
enum  { kSingleKey = BIT(0) , kOverwrite = BIT(1) , kWriteDelete = BIT(2) }
 
enum  EDeprecatedStatusBits { kObjInCanvas = BIT(3) }
 
enum  EStatusBits {
  kCanDelete = BIT(0) , kMustCleanup = BIT(3) , kIsReferenced = BIT(4) , kHasUUID = BIT(5) ,
  kCannotPick = BIT(6) , kNoContextMenu = BIT(8) , kInvalidObject = BIT(13)
}
 
- Protected Types inherited from TObject
enum  { kOnlyPrepStep = BIT(3) }
 
- 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).
 
void MakeZombie ()
 

#include <TAttImage.h>

Inheritance diagram for TImagePalette:
[legend]

Constructor & Destructor Documentation

◆ TImagePalette() [1/4]

TImagePalette::TImagePalette ( )

Default constructor, sets all pointers to 0.

Definition at line 270 of file TAttImage.cxx.

◆ TImagePalette() [2/4]

TImagePalette::TImagePalette ( const TImagePalette palette)

Copy constructor.

Definition at line 297 of file TAttImage.cxx.

◆ TImagePalette() [3/4]

TImagePalette::TImagePalette ( UInt_t  numPoints)

Constructor for a palette with numPoints anchor points.

It allocates the memory but does not set any colors.

Definition at line 284 of file TAttImage.cxx.

◆ TImagePalette() [4/4]

TImagePalette::TImagePalette ( Int_t  ncolors,
Int_t colors 
)

Creates palette in the same way as TStyle::SetPalette.

Definition at line 317 of file TAttImage.cxx.

◆ ~TImagePalette()

TImagePalette::~TImagePalette ( )
virtual

Destructor.

Definition at line 441 of file TAttImage.cxx.

Member Function Documentation

◆ Create()

TImagePalette * TImagePalette::Create ( Option_t opts)
static

Factory method to creates an image palette of a specific typ.

Create a new palette

This creates a new TImagePalette based on the option specified in the parameter. The supported options are:

  • "col" - color palette similar in TStyle (i.e. use for "col" option)
  • "web" - color palette similar to gWebImagePalette
  • "hist" - color palette similar to gHistImagePalette
Parameters
optsthe type of palette to create

Ownership of the returned object transfers to the caller.

Return values
newpalette
nullptr- option does not exist

Definition at line 702 of file TAttImage.cxx.

◆ CreateCOLPalette()

TImagePalette * TImagePalette::CreateCOLPalette ( Int_t  ncontours)
static

Factory method to creates an image palette for histogram plotting.

Creates a "col" palette with correct number of contours

The behavior is similar to the TImagePalette::Create() method with the "col" option. The difference here is that the palette will only contain a specific number of colors. This method is used to create the palette used in the "col2" and "colz2" options. It handles the color selection for contours.

Parameters
ncontoursnumber of contours

Ownership of the returned object transfers to the caller.

Returns
new palette

Definition at line 748 of file TAttImage.cxx.

◆ FindColor()

Int_t TImagePalette::FindColor ( UShort_t  r,
UShort_t  g,
UShort_t  b 
)
virtual

Returns an index of the closest color.

Reimplemented in TWebPalette.

Definition at line 485 of file TAttImage.cxx.

◆ GetRootColors()

Int_t * TImagePalette::GetRootColors ( )
virtual

Returns a list of ROOT colors.

Could be used to set histogram palette. See also TStyle::SetPalette

Reimplemented in TWebPalette, and TDefHistImagePalette.

Definition at line 507 of file TAttImage.cxx.

◆ operator=()

TImagePalette & TImagePalette::operator= ( const TImagePalette palette)

Assignment operator.

Definition at line 453 of file TAttImage.cxx.

Member Data Documentation

◆ fColorAlpha

UShort_t* TImagePalette::fColorAlpha

[fNumPoints] alpha at each anchor point

Definition at line 41 of file TAttImage.h.

◆ fColorBlue

UShort_t* TImagePalette::fColorBlue

[fNumPoints] blue color at each anchor point

Definition at line 40 of file TAttImage.h.

◆ fColorGreen

UShort_t* TImagePalette::fColorGreen

[fNumPoints] green color at each anchor point

Definition at line 39 of file TAttImage.h.

◆ fColorRed

UShort_t* TImagePalette::fColorRed

[fNumPoints] red color at each anchor point

Definition at line 38 of file TAttImage.h.

◆ fNumPoints

UInt_t TImagePalette::fNumPoints

number of anchor points

Definition at line 36 of file TAttImage.h.

◆ fPoints

Double_t* TImagePalette::fPoints

[fNumPoints] value of each anchor point [0..1]

Definition at line 37 of file TAttImage.h.

Libraries for TImagePalette:

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