y.layout.hierarchic
Class MedianDrawerWrapper

java.lang.Object
  y.layout.hierarchic.MedianDrawerWrapper

All Implemented Interfaces:

Drawer

public class MedianDrawerWrapper
extends java.lang.Object
implements Drawer

This class can be used for improving the results of different drawers.

It is designed as a wrapper to another drawer (especially SimplexDrawer). It will insert additional dummy nodes for each node that has an even number of incoming edges or outgoing edges. Dummy nodes will be inserted in the neighboring layer at the center of the other edges' opposite nodes.

The produced drawings are considered to be more symmetric.

Field Summary

protected Drawer	drawerDelegate The delegate Drawer instance that will perform the actual drawing.
protected NodeMap	dummy A NodeMap used for identifying dummy nodes.

Fields inherited from interface y.layout.hierarchic.Drawer

NODE_BORDER_BOTTOM, NODE_BORDER_LEFT, NODE_BORDER_RIGHT, NODE_BORDER_TOP, NODE_DISTANCE

Constructor Summary

MedianDrawerWrapper(Drawer drawerDelegate)
Creates an instance of MedianDrawerWrapper using the delegate Drawer instance to perform the core work.

Method Summary

void	assignCoordinates(LayoutGraph graph, NodeList[] layerLists, DataProvider layerID) Assigns the coordinates to the nodes of the given graph.
Drawer	getDelegate() Returns the Drawer to which the actual drawing is delegated.
protected void	postprocess(LayoutGraph graph, NodeList[] layerLists, NodeMap layerID) Called as a hook after the actual drawing is performed by the delegate Drawer instance.
protected void	preprocess(LayoutGraph graph, NodeList[] layerLists, NodeMap layerID) Called as a hook before the actual drawing is performed by the delegate Drawer instance.
void	setDelegate(Drawer drawerDelegate) Specifies the Drawer to which the actual drawing is delegated.
void	setDummyMap(NodeMap dummyMap) Specifies a NodeMap instance for identifying the dummy nodes from the real ones.
void	setMinimalEdgeDistance(double d) Specifies the minimum distance between two edges that span the same layer.
void	setMinimalLayerDistance(double d) Specifies the minimum distance between two layers.
void	setMinimalMultiEdgeDistance(double d) Specifies the minimum distance between two edges sharing source/target in the same layer.
void	setMinimalNodeDistance(double d) Specifies the minimum distance between two nodes in the same layer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

drawerDelegate

protected Drawer drawerDelegate

The delegate Drawer instance that will perform the actual drawing.

See Also:

setDummyMap(NodeMap)

dummy

protected NodeMap dummy

A NodeMap used for identifying dummy nodes.

It returns the original edge for each dummy node or null for real nodes.

See Also:

setDummyMap(y.base.NodeMap)

Constructor Detail

MedianDrawerWrapper

public MedianDrawerWrapper(Drawer drawerDelegate)

Creates an instance of MedianDrawerWrapper using the delegate Drawer instance to perform the core work.

Parameters:

drawerDelegate - the delegate Drawer instance

Method Detail

assignCoordinates

public void assignCoordinates(LayoutGraph graph,
                              NodeList[] layerLists,
                              DataProvider layerID)

Description copied from interface: Drawer

Assigns the coordinates to the nodes of the given graph.

Specified by:

assignCoordinates in interface Drawer

Parameters:

graph - the graph

layerLists - the array of NodeLists each of which contains nodes that belong to the same layer

layerID - the DataProvider that returns the zero-based index of the layer to which each node belongs

setDummyMap

public void setDummyMap(NodeMap dummyMap)

Specifies a NodeMap instance for identifying the dummy nodes from the real ones.

Specified by:

setDummyMap in interface Drawer

Parameters:

dummyMap - the NodeMap that returns the original edge for each dummy node or null for real nodes

setMinimalEdgeDistance

public void setMinimalEdgeDistance(double d)

Specifies the minimum distance between two edges that span the same layer.

Minimum distance must be non-negative.

Specified by:

setMinimalEdgeDistance in interface Drawer

Default Value:

The default value is 5.0.

Parameters:

d - the minimum distance between two edges

Throws:

java.lang.IllegalArgumentException - if the minimum distance is negative

Sample Graphs:

Edge distance 10

Edge distance 100

setMinimalLayerDistance

public void setMinimalLayerDistance(double d)

Specifies the minimum distance between two layers.

Minimum distance must be non-negative.

Specified by:

setMinimalLayerDistance in interface Drawer

Default Value:

The default value is 60.0.

Parameters:

d - the minimum distance between two edges sharing source/target

Throws:

java.lang.IllegalArgumentException - if the minimum distance is negative

Sample Graphs:

Layer distance 40

Layer distance 100

setMinimalMultiEdgeDistance

public void setMinimalMultiEdgeDistance(double d)

Specifies the minimum distance between two edges sharing source/target in the same layer.

Minimum distance must be non-negative.

Specified by:

setMinimalMultiEdgeDistance in interface Drawer

Default Value:

The default value is 0.0.

Parameters:

d - the minimum distance between two edges sharing source/target

Throws:

java.lang.IllegalArgumentException - if the minimum distance is negative

Sample Graphs:

Multi-edge distance 10

Multi-edge distance 200

setMinimalNodeDistance

public void setMinimalNodeDistance(double d)

Specifies the minimum distance between two nodes in the same layer.

Minimum distance must be non-negative.

Specified by:

setMinimalNodeDistance in interface Drawer

Default Value:

The default value is 20.0.

Parameters:

d - the minimum distance between two edges sharing source/target

Throws:

java.lang.IllegalArgumentException - if the minimum distance is negative

Sample Graphs:

Node distance 10

Node distance 100

preprocess

protected void preprocess(LayoutGraph graph,
                          NodeList[] layerLists,
                          NodeMap layerID)

Called as a hook before the actual drawing is performed by the delegate Drawer instance.

This method is called by assignCoordinates(LayoutGraph, NodeList[], DataProvider) and calculates the dummy nodes that have to be inserted to the graph for each node that has an even number of incoming edges or outgoing edges. These nodes are being removed in postprocess(LayoutGraph, NodeList[], NodeMap) method.

Parameters:

graph - the graph

layerLists - an array of NodeLists each of which contains nodes that belong to the same layer

layerID - the NodeMap that will be filled during the calculation and holds the zero-based index of the layer to which each node belongs

See Also:

postprocess(LayoutGraph, NodeList[], NodeMap)

postprocess

protected void postprocess(LayoutGraph graph,
                           NodeList[] layerLists,
                           NodeMap layerID)

Called as a hook after the actual drawing is performed by the delegate Drawer instance.

This method is called by assignCoordinates(LayoutGraph, NodeList[], DataProvider) as a last step in order to remove the dummy nodes inserted by preprocess(LayoutGraph, NodeList[], NodeMap) method and restore the graph.

Parameters:

graph - the graph

layerLists - an array of NodeLists each of which contains nodes that belong to the same layer

layerID - the NodeMap that returns the zero-based index of the layer to which each node belongs

See Also:

postprocess(LayoutGraph, NodeList[], NodeMap)

getDelegate

public Drawer getDelegate()

Returns the Drawer to which the actual drawing is delegated.

Returns:

the Drawer instance that performs the actual drawing

See Also:

setDelegate(Drawer)

setDelegate

public void setDelegate(Drawer drawerDelegate)

Specifies the Drawer to which the actual drawing is delegated.

Parameters:

drawerDelegate - the given Drawer instance that performs the actual drawing