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 v.2015.05
 

ogdf::DavidsonHarelLayout Class Reference

The Davidson-Harel layout algorithm. More...

#include <ogdf/energybased/DavidsonHarelLayout.h>

+ Inheritance diagram for ogdf::DavidsonHarelLayout:

Public Types

enum  SettingsParameter { spStandard, spRepulse, spPlanar }
 Easy way to set fixed costs. More...
 
enum  SpeedParameter { sppFast, sppMedium, sppHQ }
 Easy way to set temperature and iterations. More...
 

Public Member Functions

 DavidsonHarelLayout ()
 Creates an instance of Davidson-Harel layout. More...
 
 ~DavidsonHarelLayout ()
 
void call (GraphAttributes &GA)
 Calls the layout algorithm for graph attributes GA. More...
 
void fixSettings (SettingsParameter sp)
 Fixes the cost values to special configurations. More...
 
double getAttractionWeight () const
 Returns the weight for the energy function Attraction. More...
 
double getNodeOverlapWeight () const
 Returns the weight for the energy function NodeOverlap. More...
 
int getNumberOfIterations () const
 Returns the number of iterations per temperature step. More...
 
double getPlanarityWeight () const
 Returns the weight for the energy function Planarity. More...
 
double getRepulsionWeight () const
 Returns the weight for the energy function Repulsion. More...
 
int getStartTemperature () const
 Returns the starting temperature. More...
 
void setAttractionWeight (double)
 Sets the weight for the energy function Attraction. More...
 
void setIterationNumberAsFactor (bool b)
 
void setNodeOverlapWeight (double)
 Sets the weight for the energy function NodeOverlap. More...
 
void setNumberOfIterations (int steps)
 Sets the number of iterations per temperature step to steps. More...
 
void setPlanarityWeight (double)
 Sets the weight for the energy function Planarity. More...
 
void setPreferredEdgeLength (double elen)
 Sets the preferred edge length to elen. More...
 
void setPreferredEdgeLengthMultiplier (double multi)
 Sets the preferred edge length multiplier for attraction. More...
 
void setRepulsionWeight (double w)
 Sets the weight for the energy function Repulsion. More...
 
void setSpeed (SpeedParameter sp)
 More convenient way of setting the speed of the algorithm. More...
 
void setStartTemperature (int t)
 Sets the starting temperature to t. More...
 
- Public Member Functions inherited from ogdf::LayoutModule
 LayoutModule ()
 Initializes a layout module. More...
 
virtual ~LayoutModule ()
 
virtual void call (GraphAttributes &GA, GraphConstraints &GC)
 Computes a layout of graph GA wrt the constraints in GC (if applicable). More...
 
void operator() (GraphAttributes &GA)
 Computes a layout of graph GA. More...
 

Private Attributes

double m_attractionWeight
 The weight for attraction energy. More...
 
bool m_crossings
 Should crossings be computed? More...
 
bool m_itAsFactor
 Should m_numberOfIterations be factor (true) or fixed number. More...
 
double m_multiplier
 By default, number of iterations per temperature step is number of vertices multiplied by multiplier. More...
 
double m_nodeOverlapWeight
 The weight for node overlap energy. More...
 
int m_numberOfIterations
 The number of iterations per temperature step. More...
 
double m_planarityWeight
 The weight for edge crossing energy. More...
 
double m_prefEdgeLength
 Preferred edge length (abs value), only used if > 0. More...
 
double m_repulsionWeight
 The weight for repulsion energy. More...
 
SpeedParameter m_speed
 You can override this by manually setting iter=0. More...
 
int m_startTemperature
 The temperature at the start of the optimization. More...
 

Detailed Description

The Davidson-Harel layout algorithm.

The implementation used in DavidsonHarelLayout is based on the following publication:

Ron Davidson, David Harel: Drawing Graphs Nicely Using Simulated Annealing. ACM Transactions on Graphics 15(4), pp. 301-331, 1996.

Definition at line 69 of file DavidsonHarelLayout.h.

Member Enumeration Documentation

Easy way to set fixed costs.

Enumerator
spStandard 
spRepulse 
spPlanar 

Definition at line 73 of file DavidsonHarelLayout.h.

Easy way to set temperature and iterations.

Enumerator
sppFast 
sppMedium 
sppHQ 

Definition at line 76 of file DavidsonHarelLayout.h.

Constructor & Destructor Documentation

ogdf::DavidsonHarelLayout::DavidsonHarelLayout ( )

Creates an instance of Davidson-Harel layout.

ogdf::DavidsonHarelLayout::~DavidsonHarelLayout ( )
inline

Definition at line 81 of file DavidsonHarelLayout.h.

Member Function Documentation

void ogdf::DavidsonHarelLayout::call ( GraphAttributes GA)
virtual

Calls the layout algorithm for graph attributes GA.

Implements ogdf::LayoutModule.

void ogdf::DavidsonHarelLayout::fixSettings ( SettingsParameter  sp)

Fixes the cost values to special configurations.

double ogdf::DavidsonHarelLayout::getAttractionWeight ( ) const
inline

Returns the weight for the energy function Attraction.

Definition at line 116 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::getNodeOverlapWeight ( ) const
inline

Returns the weight for the energy function NodeOverlap.

Definition at line 122 of file DavidsonHarelLayout.h.

int ogdf::DavidsonHarelLayout::getNumberOfIterations ( ) const
inline

Returns the number of iterations per temperature step.

Definition at line 140 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::getPlanarityWeight ( ) const
inline

Returns the weight for the energy function Planarity.

Definition at line 128 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::getRepulsionWeight ( ) const
inline

Returns the weight for the energy function Repulsion.

Definition at line 110 of file DavidsonHarelLayout.h.

int ogdf::DavidsonHarelLayout::getStartTemperature ( ) const
inline

Returns the starting temperature.

Definition at line 134 of file DavidsonHarelLayout.h.

void ogdf::DavidsonHarelLayout::setAttractionWeight ( double  )

Sets the weight for the energy function Attraction.

void ogdf::DavidsonHarelLayout::setIterationNumberAsFactor ( bool  b)
inline

Switch between using iteration number as fixed number or factor (*number of nodes of graph)

Definition at line 144 of file DavidsonHarelLayout.h.

void ogdf::DavidsonHarelLayout::setNodeOverlapWeight ( double  )

Sets the weight for the energy function NodeOverlap.

void ogdf::DavidsonHarelLayout::setNumberOfIterations ( int  steps)

Sets the number of iterations per temperature step to steps.

void ogdf::DavidsonHarelLayout::setPlanarityWeight ( double  )

Sets the weight for the energy function Planarity.

void ogdf::DavidsonHarelLayout::setPreferredEdgeLength ( double  elen)
inline

Sets the preferred edge length to elen.

Definition at line 104 of file DavidsonHarelLayout.h.

void ogdf::DavidsonHarelLayout::setPreferredEdgeLengthMultiplier ( double  multi)
inline

Sets the preferred edge length multiplier for attraction.

This is bad design, cause you dont need to have an attraction function, DH is purely modular and independent with its cost functions.

Definition at line 101 of file DavidsonHarelLayout.h.

void ogdf::DavidsonHarelLayout::setRepulsionWeight ( double  w)

Sets the weight for the energy function Repulsion.

void ogdf::DavidsonHarelLayout::setSpeed ( SpeedParameter  sp)

More convenient way of setting the speed of the algorithm.

Influences number of iterations per temperature step, starting temperature, and cooling factor.

void ogdf::DavidsonHarelLayout::setStartTemperature ( int  t)

Sets the starting temperature to t.

Member Data Documentation

double ogdf::DavidsonHarelLayout::m_attractionWeight
private

The weight for attraction energy.

Definition at line 148 of file DavidsonHarelLayout.h.

bool ogdf::DavidsonHarelLayout::m_crossings
private

Should crossings be computed?

Definition at line 156 of file DavidsonHarelLayout.h.

bool ogdf::DavidsonHarelLayout::m_itAsFactor
private

Should m_numberOfIterations be factor (true) or fixed number.

Definition at line 157 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::m_multiplier
private

By default, number of iterations per temperature step is number of vertices multiplied by multiplier.

Definition at line 154 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::m_nodeOverlapWeight
private

The weight for node overlap energy.

Definition at line 149 of file DavidsonHarelLayout.h.

int ogdf::DavidsonHarelLayout::m_numberOfIterations
private

The number of iterations per temperature step.

Definition at line 152 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::m_planarityWeight
private

The weight for edge crossing energy.

Definition at line 150 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::m_prefEdgeLength
private

Preferred edge length (abs value), only used if > 0.

Definition at line 155 of file DavidsonHarelLayout.h.

double ogdf::DavidsonHarelLayout::m_repulsionWeight
private

The weight for repulsion energy.

Definition at line 147 of file DavidsonHarelLayout.h.

SpeedParameter ogdf::DavidsonHarelLayout::m_speed
private

You can override this by manually setting iter=0.

Definition at line 153 of file DavidsonHarelLayout.h.

int ogdf::DavidsonHarelLayout::m_startTemperature
private

The temperature at the start of the optimization.

Definition at line 151 of file DavidsonHarelLayout.h.


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