Line Attributes class.

This class is used (in general by secondary inheritance) by many other classes (graphics, histograms). It holds all the line attributes.

Line attributes

Line attributes are:

Line Color
Line Width
Line Style

Line Color

The line color is a color index (integer) pointing in the ROOT color table. The line color of any class inheriting from TAttLine can be changed using the method SetLineColor and retrieved using the method GetLineColor. The following table shows the first 50 default colors.

Color transparency

SetLineColorAlpha(), allows to set a transparent color. In the following example the line color of the histogram histo is set to blue with a transparency of 35%. The color kBlue itself remains fully opaque.

histo->SetLineColorAlpha(kBlue, 0.35);

The transparency is available on all platforms when the flagOpenGL.CanvasPreferGL is set to 1 in $ROOTSYS/etc/system.rootrc, or on Mac with the Cocoa backend. On the file output it is visible with PDF, PNG, Gif, JPEG, SVG ... but not PostScript.

Line Width

The line width is expressed in pixel units. The line width of any class inheriting from TAttLine can be changed using the method SetLineWidth and retrieved using the method GetLineWidth. The following picture shows the line widths from 1 to 10 pixels.

Line Style

Line styles are identified via integer numbers. The line style of any class inheriting from TAttLine can be changed using the method SetLineStyle and retrieved using the method GetLineStyle.

The first 10 line styles are predefined as shown on the following picture:

Additional line styles can be defined using TStyle::SetLineStyleString. For example the line style number 11 can be defined as follow:

gStyle->SetLineStyleString(11,"400 200");

Existing line styles (1 to 10) can be redefined using the same method.

Definition at line 24 of file TAttLine.h.

Public Member Functions
	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...

Protected Attributes
Color_t	fLineColor
	Line color. More...

Style_t	fLineStyle
	Line style. More...

Width_t	fLineWidth
	Line width. More...

#include <TAttLine.h>

Inheritance diagram for TAttLine:

[legend]

Constructor & Destructor Documentation

◆ TAttLine() [1/2]

TAttLine::TAttLine ( )

AttLine default constructor.

Definition at line 128 of file TAttLine.cxx.

◆ TAttLine() [2/2]

TAttLine::TAttLine	(	Color_t	color,
		Style_t	style,
		Width_t	width
	)

AttLine normal constructor.

Line attributes are taking from the argument list

color : must be one of the valid color index
style : 1=solid, 2=dash, 3=dash-dot, 4=dot-dot. New styles can be defined using TStyle::SetLineStyleString.
width : expressed in pixel units

Definition at line 145 of file TAttLine.cxx.

◆ ~TAttLine()

TAttLine::~TAttLine ( )

virtual

AttLine destructor.

Definition at line 155 of file TAttLine.cxx.

Member Function Documentation

◆ Copy()

void TAttLine::Copy ( TAttLine & attline ) const

Copy this line attributes to a new TAttLine.

Definition at line 162 of file TAttLine.cxx.

◆ DistancetoLine()

Int_t TAttLine::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.

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

Algorithm:

  A(x1,y1)         P                             B(x2,y2)
  -----------------+------------------------------
                   |
                   |
                   |
                   |
                  M(x,y)
Let us call  a = distance AM     A=a**2
             b = distance BM     B=b**2
             c = distance AB     C=c**2
             d = distance PM     D=d**2
             u = distance AP     U=u**2
             v = distance BP     V=v**2     c = u + v
D = A - U
D = B - V  = B -(c-u)**2
   ==> u = (A -B +C)/2c

Definition at line 196 of file TAttLine.cxx.

◆ GetLineColor()

virtual Color_t TAttLine::GetLineColor ( ) const

inlinevirtual

Return the line color.

Reimplemented in TGWin32VirtualXProxy.

Definition at line 39 of file TAttLine.h.

◆ GetLineStyle()

virtual Style_t TAttLine::GetLineStyle ( ) const

inlinevirtual

Return the line style.

Reimplemented in TGWin32VirtualXProxy.

Definition at line 40 of file TAttLine.h.

◆ GetLineWidth()

virtual Width_t TAttLine::GetLineWidth ( ) const

inlinevirtual

Return the line width.

Reimplemented in TGWin32VirtualXProxy.

Definition at line 41 of file TAttLine.h.

◆ Modify()

void TAttLine::Modify ( )

virtual

Change current line attributes if necessary.

Definition at line 232 of file TAttLine.cxx.

◆ ResetAttLine()

void TAttLine::ResetAttLine ( Option_t * option = "" )

virtual

Reset this line attributes to default values.

Reimplemented in TGWin32VirtualXProxy.

Definition at line 250 of file TAttLine.cxx.

◆ SaveLineAttributes()

void TAttLine::SaveLineAttributes	(	std::ostream &	out,
		const char *	name,
		Int_t	coldef = `1`,
		Int_t	stydef = `1`,
		Int_t	widdef = `1`
	)

virtual

Save line attributes as C++ statement(s) on output stream out.

Definition at line 260 of file TAttLine.cxx.

◆ SetLineAttributes()

void TAttLine::SetLineAttributes ( )

virtual

Invoke the DialogCanvas Line attributes.

Reimplemented in TGWin32VirtualXProxy.

Definition at line 280 of file TAttLine.cxx.

◆ SetLineColor()

virtual void TAttLine::SetLineColor ( Color_t lcolor )

inlinevirtual

Set the line color.

Reimplemented in TGeoVolumeMulti, TGeoVolume, TGX11, TGWin32, TEveTrackList, TVirtualX, TSpider, TPostScript, TGWin32VirtualXProxy, TPDF, TEveStraightLineSet, TPaletteAxis, TGQuartz, TParallelCoordRange, TTeXDump, TSVG, and TEveLine.

Definition at line 46 of file TAttLine.h.

◆ SetLineColorAlpha()

void TAttLine::SetLineColorAlpha	(	Color_t	lcolor,
		Float_t	lalpha
	)

virtual

Set a transparent line color.

lalpha defines the percentage of the color opacity from 0. (fully transparent) to 1. (fully opaque).

Definition at line 289 of file TAttLine.cxx.

◆ SetLineStyle()

virtual void TAttLine::SetLineStyle ( Style_t lstyle )

inlinevirtual

Set the line style.

Reimplemented in TGeoVolumeMulti, TGeoVolume, TGX11, TGWin32, TEveTrackList, TVirtualX, TSpider, TPostScript, TGWin32VirtualXProxy, TPDF, TGQuartz, TTeXDump, TSVG, and TEveLine.

Definition at line 48 of file TAttLine.h.

◆ SetLineWidth()

virtual void TAttLine::SetLineWidth ( Width_t lwidth )

inlinevirtual

Set the line width.

Reimplemented in TGeoVolumeMulti, TGeoVolume, TGX11, TGWin32, TEveTrackList, TVirtualX, TSpider, TPostScript, TGWin32VirtualXProxy, TPDF, TPaletteAxis, TGQuartz, TTeXDump, TParallelCoordRange, TSVG, and TEveLine.

Definition at line 49 of file TAttLine.h.

Member Data Documentation

◆ fLineColor

Color_t TAttLine::fLineColor

protected

Line color.

Definition at line 27 of file TAttLine.h.

◆ fLineStyle

Style_t TAttLine::fLineStyle

protected

Line style.

Definition at line 28 of file TAttLine.h.

◆ fLineWidth

Width_t TAttLine::fLineWidth

protected

Line width.

Definition at line 29 of file TAttLine.h.

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

core/base/inc/TAttLine.h
core/base/src/TAttLine.cxx

Line attributes

Line Color

Color transparency

Line Width

Line Style

Public Member Functions

Protected Attributes

Constructor & Destructor Documentation

◆ TAttLine() [1/2]

◆ TAttLine() [2/2]

◆ ~TAttLine()

Member Function Documentation

◆ Copy()

◆ DistancetoLine()

◆ GetLineColor()

◆ GetLineStyle()

◆ GetLineWidth()

◆ Modify()

◆ ResetAttLine()

◆ SaveLineAttributes()

◆ SetLineAttributes()

◆ SetLineColor()

◆ SetLineColorAlpha()

◆ SetLineStyle()

◆ SetLineWidth()

Member Data Documentation

◆ fLineColor

◆ fLineStyle

◆ fLineWidth