#include <vtkSpanTreeLayoutStrategy.h>

Inheritance diagram for vtkSpanTreeLayoutStrategy:

Collaboration diagram for vtkSpanTreeLayoutStrategy:

Public Types
typedef vtkGraphLayoutStrategy	Superclass

Public Types inherited from vtkGraphLayoutStrategy
typedef vtkObject	Superclass

Public Types inherited from vtkObject
typedef vtkObjectBase	Superclass

Public Member Functions
virtual int	IsA (const char *type)

vtkSpanTreeLayoutStrategy *	NewInstance () const

void	PrintSelf (ostream &os, vtkIndent indent)

void	Layout ()


virtual void	SetDepthFirstSpanningTree (bool)

virtual bool	GetDepthFirstSpanningTree ()

virtual void	DepthFirstSpanningTreeOn ()

virtual void	DepthFirstSpanningTreeOff ()

Public Member Functions inherited from vtkGraphLayoutStrategy
vtkGraphLayoutStrategy *	NewInstance () const

virtual void	SetGraph (vtkGraph *graph)

virtual void	Initialize ()

virtual int	IsLayoutComplete ()

virtual void	SetWeightEdges (bool state)

virtual bool	GetWeightEdges ()

virtual void	SetEdgeWeightField (const char *field)

virtual char *	GetEdgeWeightField ()

Public Member Functions inherited from vtkObject
vtkObject *	NewInstance () const

virtual void	DebugOn ()

virtual void	DebugOff ()

bool	GetDebug ()

void	SetDebug (bool debugFlag)

virtual void	Modified ()

virtual unsigned long	GetMTime ()

unsigned long	AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)

unsigned long	AddObserver (const char event, vtkCommand , float priority=0.0f)

vtkCommand *	GetCommand (unsigned long tag)

void	RemoveObserver (vtkCommand *)

void	RemoveObservers (unsigned long event, vtkCommand *)

void	RemoveObservers (const char event, vtkCommand )

int	HasObserver (unsigned long event, vtkCommand *)

int	HasObserver (const char event, vtkCommand )

void	RemoveObserver (unsigned long tag)

void	RemoveObservers (unsigned long event)

void	RemoveObservers (const char *event)

void	RemoveAllObservers ()

int	HasObserver (unsigned long event)

int	HasObserver (const char *event)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, void(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)

template<class U , class T >
unsigned long	AddObserver (unsigned long event, U observer, bool(T::callback)(vtkObject , unsigned long, void *), float priority=0.0f)

int	InvokeEvent (unsigned long event, void *callData)

int	InvokeEvent (const char event, void callData)

int	InvokeEvent (unsigned long event)

int	InvokeEvent (const char *event)

Public Member Functions inherited from vtkObjectBase
const char *	GetClassName () const

virtual void	Delete ()

virtual void	FastDelete ()

void	Print (ostream &os)

virtual void	Register (vtkObjectBase *o)

virtual void	UnRegister (vtkObjectBase *o)

void	SetReferenceCount (int)

void	PrintRevisions (ostream &)

virtual void	PrintHeader (ostream &os, vtkIndent indent)

virtual void	PrintTrailer (ostream &os, vtkIndent indent)

int	GetReferenceCount ()

Static Public Member Functions
static vtkSpanTreeLayoutStrategy *	New ()

static int	IsTypeOf (const char *type)

static vtkSpanTreeLayoutStrategy *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkGraphLayoutStrategy
static int	IsTypeOf (const char *type)

static vtkGraphLayoutStrategy *	SafeDownCast (vtkObjectBase *o)

Static Public Member Functions inherited from vtkObject
static int	IsTypeOf (const char *type)

static vtkObject *	SafeDownCast (vtkObjectBase *o)

static vtkObject *	New ()

static void	BreakOnError ()

static void	SetGlobalWarningDisplay (int val)

static void	GlobalWarningDisplayOn ()

static void	GlobalWarningDisplayOff ()

static int	GetGlobalWarningDisplay ()

Static Public Member Functions inherited from vtkObjectBase
static int	IsTypeOf (const char *name)

static vtkObjectBase *	New ()

Protected Member Functions
virtual vtkObjectBase *	NewInstanceInternal () const

	vtkSpanTreeLayoutStrategy ()

	~vtkSpanTreeLayoutStrategy ()

Protected Member Functions inherited from vtkGraphLayoutStrategy
	vtkGraphLayoutStrategy ()

	~vtkGraphLayoutStrategy ()

Protected Member Functions inherited from vtkObject
	vtkObject ()

virtual	~vtkObject ()

virtual void	RegisterInternal (vtkObjectBase *, int check)

virtual void	UnRegisterInternal (vtkObjectBase *, int check)

void	InternalGrabFocus (vtkCommand mouseEvents, vtkCommand keypressEvents=NULL)

void	InternalReleaseFocus ()

Protected Member Functions inherited from vtkObjectBase
	vtkObjectBase ()

virtual	~vtkObjectBase ()

virtual void	CollectRevisions (ostream &)

virtual void	ReportReferences (vtkGarbageCollector *)

	vtkObjectBase (const vtkObjectBase &)

void	operator= (const vtkObjectBase &)

Protected Attributes
vtkGraphLayoutStrategy *	TreeLayout

bool	DepthFirstSpanningTree

Protected Attributes inherited from vtkGraphLayoutStrategy
vtkGraph *	Graph

char *	EdgeWeightField

bool	WeightEdges

Protected Attributes inherited from vtkObject
bool	Debug

vtkTimeStamp	MTime

vtkSubjectHelper *	SubjectHelper

Protected Attributes inherited from vtkObjectBase
vtkAtomicInt32	ReferenceCount

vtkWeakPointerBase **	WeakPointers

Detailed Description

vtkSpanTreeLayout is a strategy for drawing directed graphs that works by first extracting a spanning tree (more accurately, a spanning forest), and using this both to position graph vertices and to plan the placement of non-tree edges. The latter are drawn with the aid of edge points to produce a tidy drawing.

The approach is best suited to "quasi-trees", graphs where the number of edges is of the same order as the number of nodes; it is less well suited to denser graphs. The boolean flag DepthFirstSpanningTree determines whether a depth-first or breadth-first strategy is used to construct the underlying forest, and the choice of strategy affects the output layout significantly. Informal experiments suggest that the breadth-first strategy is better for denser graphs.

Different layouts could also be produced by plugging in alternative tree layout strategies. To work with the method of routing non-tree edges, any strategy should draw a tree so that levels are equally spaced along the z-axis, precluding for example the use of a radial or balloon layout.

vtkSpanTreeLayout is based on an approach to 3D graph layout first developed as part of the "tulip" tool by Dr. David Auber at LaBRI, U.Bordeaux: see www.tulip-software.org

This implementation departs from the original version in that: (a) it is reconstructed to use Titan/VTK data structures; (b) it uses a faster method for dealing with non-tree edges, requiring at most two edge points per edge (c) allows for plugging in different tree layout methods (d) allows selection of two different strategies for building the underlying layout tree, which can yield significantly different results depending on the data.

Thanks:: Thanks to David Duke from the University of Leeds for providing this implementation.

Examples:: vtkSpanTreeLayoutStrategy (Examples)

Definition at line 70 of file vtkSpanTreeLayoutStrategy.h.

Member Typedef Documentation

typedef vtkGraphLayoutStrategy vtkSpanTreeLayoutStrategy::Superclass

Definition at line 75 of file vtkSpanTreeLayoutStrategy.h.

Constructor & Destructor Documentation

vtkSpanTreeLayoutStrategy::vtkSpanTreeLayoutStrategy ( )

protected

vtkSpanTreeLayoutStrategy::~vtkSpanTreeLayoutStrategy ( )

protected

Member Function Documentation

static vtkSpanTreeLayoutStrategy* vtkSpanTreeLayoutStrategy::New ( )

static

static int vtkSpanTreeLayoutStrategy::IsTypeOf ( const char * type )

static

virtual int vtkSpanTreeLayoutStrategy::IsA ( const char * name )

virtual

Return 1 if this class is the same type of (or a subclass of) the named class. Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkGraphLayoutStrategy.

static vtkSpanTreeLayoutStrategy* vtkSpanTreeLayoutStrategy::SafeDownCast ( vtkObjectBase * o )

static

virtual vtkObjectBase* vtkSpanTreeLayoutStrategy::NewInstanceInternal ( ) const

protectedvirtual

Reimplemented from vtkGraphLayoutStrategy.

vtkSpanTreeLayoutStrategy* vtkSpanTreeLayoutStrategy::NewInstance ( ) const

void vtkSpanTreeLayoutStrategy::PrintSelf	(	ostream &	os,
		vtkIndent	indent
	)

virtual

Methods invoked by print to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkGraphLayoutStrategy.

virtual void vtkSpanTreeLayoutStrategy::SetDepthFirstSpanningTree ( bool )

virtual

If set, base the layout on a depth-first spanning tree, rather than the default breadth-first spanning tree. Switching between DFT and BFT may significantly change the layout, and choice must be made on a per-graph basis. Default value is off.

virtual bool vtkSpanTreeLayoutStrategy::GetDepthFirstSpanningTree ( )

virtual

If set, base the layout on a depth-first spanning tree, rather than the default breadth-first spanning tree. Switching between DFT and BFT may significantly change the layout, and choice must be made on a per-graph basis. Default value is off.

virtual void vtkSpanTreeLayoutStrategy::DepthFirstSpanningTreeOn ( )

virtual

If set, base the layout on a depth-first spanning tree, rather than the default breadth-first spanning tree. Switching between DFT and BFT may significantly change the layout, and choice must be made on a per-graph basis. Default value is off.

virtual void vtkSpanTreeLayoutStrategy::DepthFirstSpanningTreeOff ( )

virtual

If set, base the layout on a depth-first spanning tree, rather than the default breadth-first spanning tree. Switching between DFT and BFT may significantly change the layout, and choice must be made on a per-graph basis. Default value is off.

void vtkSpanTreeLayoutStrategy::Layout ( )

virtual

Perform the layout.

Implements vtkGraphLayoutStrategy.