ilog.tgo.graphic.graphlayout
Class IltLocalLinkLayout

java.lang.Object
  ilog.views.graphlayout.IlvGraphLayout
      ilog.tgo.graphic.graphlayout.IltLocalLinkLayout

All Implemented Interfaces:

GraphModelListener, Serializable, EventListener

public class IltLocalLinkLayout
extends IlvGraphLayout

This is a simple link layout algorithm: All links are straight lines between the nearest sides of two nodes. A simple form of local disentanglement is applied.

Since:

JTGO 2.6

See Also:

Serialized Form

Field Summary

static boolean	AvoidAcuteAngles When set to true, acute angles will be avoided by inserting additional points.
static boolean	AvoidZigZag When set to true, zig-zag shapes with two acute angles will be turned into 90 deg. angles.

Fields inherited from class ilog.views.graphlayout.IlvGraphLayout

INVERSE_VIEW_COORDINATES, MANAGER_COORDINATES, VIEW_COORDINATES

Constructor Summary

IltLocalLinkLayout()
Creates a new instance of the Local Link Layout algorithm.

IltLocalLinkLayout(IltLocalLinkLayout source)
Creates a new layout instance by copying an existing one.

Method Summary

IlvRect	borderedBoundingBox(IlvGraphModel model, Object obj)
protected IlpPolyline	chooseShape(IlvGraphModel model, Object link) Chooses and returns the desired shape for a link.
protected void	commitConnection(IlvGraphModel model, Object link, Object node, ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side) Registers that a given link to a given node is to be connected at a given side of this node.
protected void	connectLink(IlvGraphModel model, Object link) Connects a link to its ends, by calling commitConnection() once for each of the two ends.
protected void	connectSelfLink(IlvGraphModel model, Object link)
IlvGraphLayout	copy() Copies the layout instance.
void	copyParameters(IlvGraphLayout source) Copies the parameters from a given layout instance.
protected ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.Socket	getConnectionSocket(IlvGraphModel model, Object link, Object node) Once commitConnection has been called with a link and a node as arguments, returns the socket where the link starts.
float	getLinkDistance()
float	getNodeBorderWidth()
protected void	init() Initializes instance variables.
protected void	layout(boolean redraw) Executes the layout.
protected void	placeLinks(IlvGraphModel model, Object node) Adjusts all connections ending on a given node.
protected void	placeLinks(IlvGraphModel model, Object node, ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side) Adjusts all connections ending on a given node, at a given side.
void	setLinkDistance(float distance)
void	setNodeBorderWidth(float width)
protected void	sortLinks(IlvGraphModel model, Object node) Sorts all connections ending on a given node.
protected Vector	sortLinks(IlvGraphModel model, Object node, ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side) Sorts the links ending on a given node, at a given side, so as to avoid unnecessary crossings.

Methods inherited from class ilog.views.graphlayout.IlvGraphLayout

addGraphLayoutEventListener, addGraphLayoutParameterEventListener, afterLayoutOfSubgraph, attach, attach, beforeLayout, beforeLayoutOfSubgraph, callLayoutStepPerformedIfNeeded, checkAppropriateLink, checkAppropriateLinks, cleanGraphModel, cleanLink, cleanNode, clipAllLinks, clipLink, contentsChanged, createLayoutGrapherProperty, createLayoutLinkProperty, createLayoutNodeProperty, createLayoutReport, detach, getAllowedTime, getAutoLayoutHandler, getBalanceSplineCurveThreshold, getCalcLayoutRegion, getCoordinatesMode, getGrapher, getGraphModel, getInstanceId, getLayout, getLayoutOfConnectedComponents, getLayoutOfConnectedComponentsReport, getLayoutRegion, getLayoutReport, getLayouts, getLinkClipInterface, getLinkConnectionBoxInterface, getMaxSplineCurveSize, getMinBusyTime, getMinSplineCurveSize, getMovingNodes, getParentLayout, getProperty, getProperty, getRecursiveLayout, getRemainingAllowedTime, getSeedValueForRandomGenerator, getSpecLayoutRegion, getSplineLinkFilter, increasePercentageComplete, isAnimate, isAutoLayout, isFitToView, isFixed, isGeometryUpToDate, isInputCheckEnabled, isLayoutNeeded, isLayoutOfConnectedComponentsEnabled, isLayoutOfConnectedComponentsEnabledByDefault, isLayoutRunning, isLayoutTimeElapsed, isMemorySavings, isParametersUpToDate, isPreserveFixedLinks, isPreserveFixedNodes, isSplineRoutingEnabled, isStoppedImmediately, isStructureUpToDate, isUseDefaultParameters, isUseSeedValueForRandomGenerator, layoutStepPerformed, onParameterChanged, onParameterChanged, performAutoLayout, performLayout, performLayout, performLayout, PerformLayout, performSublayout, removeGraphLayoutEventListener, removeGraphLayoutParameterEventListener, setAllowedTime, setAnimate, setAutoLayout, setAutoLayoutHandler, setBalanceSplineCurveThreshold, setCoordinatesMode, setFixed, setGeometryUpToDate, setGrapher, setGraphModel, setInputCheckEnabled, setLayoutOfConnectedComponents, setLayoutOfConnectedComponentsEnabled, setLayoutRegion, setLayoutRegion, setLayoutRegion, setLayoutReport, setLinkClipInterface, setLinkConnectionBoxInterface, setMaxSplineCurveSize, setMemorySavings, setMinBusyTime, setMinSplineCurveSize, setParametersUpToDate, setParentLayout, setPreserveFixedLinks, setPreserveFixedNodes, setProperty, setProperty, setSeedValueForRandomGenerator, setSplineLinkFilter, setSplineRoutingEnabled, setStructureUpToDate, setUseDefaultParameters, setUseSeedValueForRandomGenerator, stopImmediately, supportsAllowedTime, supportsAnimation, supportsLayoutOfConnectedComponents, supportsLayoutRegion, supportsLinkClipping, supportsLinkConnectionBox, supportsMemorySavings, supportsPercentageComplete, supportsPreserveFixedLinks, supportsPreserveFixedNodes, supportsRandomGenerator, supportsSaveParametersToNamedProperties, supportsSplineRouting, supportsStopImmediately, unfixAllLinks, unfixAllNodes, useAnimateRedraw

Methods inherited from class java.lang.Object

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

Field Detail

AvoidZigZag

public static boolean AvoidZigZag

When set to true, zig-zag shapes with two acute angles will be turned into 90 deg. angles.

Internal method or field: do not use!

AvoidAcuteAngles

public static boolean AvoidAcuteAngles

When set to true, acute angles will be avoided by inserting additional points.

Internal method or field: do not use!

Constructor Detail

IltLocalLinkLayout

public IltLocalLinkLayout()

Creates a new instance of the Local Link Layout algorithm.

IltLocalLinkLayout

public IltLocalLinkLayout(IltLocalLinkLayout source)

Creates a new layout instance by copying an existing one. This constructor is used by the copy() method. Any subclass should provide a copy constructor.

The parameters of the source layout are copied using the method copyParameters(ilog.views.graphlayout.IlvGraphLayout).

See Also:

copy(), copyParameters(ilog.views.graphlayout.IlvGraphLayout)

Method Detail

copy

public IlvGraphLayout copy()

Copies the layout instance.

This method copies the layout instance by calling the copy constructor.

Specified by:

copy in class IlvGraphLayout

Returns:

A copy of the layout instance.

getNodeBorderWidth

public float getNodeBorderWidth()

Internal method or field: do not use!

setNodeBorderWidth

public void setNodeBorderWidth(float width)

Internal method or field: do not use!

borderedBoundingBox

public IlvRect borderedBoundingBox(IlvGraphModel model,
                                   Object obj)

Internal method or field: do not use!

getLinkDistance

public float getLinkDistance()

Internal method or field: do not use!

setLinkDistance

public void setLinkDistance(float distance)

Internal method or field: do not use!

copyParameters

public void copyParameters(IlvGraphLayout source)

Copies the parameters from a given layout instance.

Overrides:

copyParameters in class IlvGraphLayout

Parameters:

source - The layout instance from which the parameters are copied.

See Also:

copy()

init

protected void init()

Description copied from class: IlvGraphLayout

Initializes instance variables.

You should not call this method directly. The method is called internally by the constructor without arguments and by the copy constructor.

The method must be overridden by subclasses that need to initialize additional instance variables. The initialization of all the instance variables of the subclasses must be done in this method.

Overrides:

init in class IlvGraphLayout

commitConnection

protected void commitConnection(IlvGraphModel model,
                                Object link,
                                Object node,
                                ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side)

Registers that a given link to a given node is to be connected at a given side of this node.

Parameters:

link - a link

node - one of the two ends of the link

side - the node's side on which the link has to start

Internal method or field: do not use!

getConnectionSocket

protected ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.Socket getConnectionSocket(IlvGraphModel model,
                                                                                     Object link,
                                                                                     Object node)

Once commitConnection has been called with a link and a node as arguments, returns the socket where the link starts.

Internal method or field: do not use!

connectLink

protected void connectLink(IlvGraphModel model,
                           Object link)

Connects a link to its ends, by calling commitConnection() once for each of the two ends. Does nothing for selflinks.

Internal method or field: do not use!

sortLinks

protected Vector sortLinks(IlvGraphModel model,
                           Object node,
                           ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side)

Sorts the links ending on a given node, at a given side, so as to avoid unnecessary crossings. Returns the sorted vector of sockets. The sockets are sorted according to increasing values of `tangentDelta/radialDelta', i.e. links starting with a turn right (or ending with a turn left) come first, links starting with a turn left come last.

Internal method or field: do not use!

sortLinks

protected void sortLinks(IlvGraphModel model,
                         Object node)

Sorts all connections ending on a given node. Stores the sorted sockets table into getNodeData(node).sortedSockets.

Internal method or field: do not use!

connectSelfLink

protected void connectSelfLink(IlvGraphModel model,
                               Object link)

Internal method or field: do not use!

placeLinks

protected void placeLinks(IlvGraphModel model,
                          Object node,
                          ilog.tgo.graphic.graphlayout.IltLocalLinkLayout.NodeSide side)

Adjusts all connections ending on a given node, at a given side.

Internal method or field: do not use!

placeLinks

protected void placeLinks(IlvGraphModel model,
                          Object node)

Adjusts all connections ending on a given node.

Internal method or field: do not use!

chooseShape

protected IlpPolyline chooseShape(IlvGraphModel model,
                                  Object link)

Chooses and returns the desired shape for a link.

Internal method or field: do not use!

layout

protected void layout(boolean redraw)
               throws IlvGraphLayoutException

Description copied from class: IlvGraphLayout

Executes the layout.

This method must be implemented by each layout algorithm (subclasses of IlvGraphLayout). This method computes the coordinates of the nodes in the attached graph model and moves the nodes to the new positions using the method IlvGraphModel.moveNode(java.lang.Object, float, float, boolean).

The method can also perform reshape operations on the links using the method IlvGraphModel.reshapeLink(java.lang.Object, ilog.views.IlvPoint, ilog.views.IlvPoint[], int, int, ilog.views.IlvPoint, boolean). Any implementation of this method must pass, for the redraw argument of these two methods, the same value as the one it receives.

When using a subclass of IlvGraphLayout, refer to the documentation of the subclass to know when this method throws an exception.

When writing the implementation of this method, you can obtain an instance of the layout report using IlvGraphLayout.getLayoutReport() and store particular information about the behavior of the layout algorithm in the layout report. You can also notify the layout event listeners using the method IlvGraphLayout.layoutStepPerformed().

When the layout algorithm is finished and if the layout is performed successfully, you must call the method IlvGraphLayoutReport.setCode(int) with the argument IlvGraphLayoutReport.LAYOUT_DONE on the layout report instance.

Here is a sample implementation for a Random layout:

 protected void layout(boolean redraw)
   throws IlvGraphLayoutException
 {
   // obtain the graph model
   IlvGraphModel graphModel = getGraphModel();
   // obtain the layout report
   IlvGraphLayoutReport layoutReport = getLayoutReport();

   boolean atLeastOneNodeMoved = false;

   // obtain the layout region
   IlvRect rect = getCalcLayoutRegion();
   float xMin = rect.x;
   float yMin = rect.y;
   float xMax = rect.x + rect.width;
   float yMax = rect.y + rect.height;

   // initialize the random generator
   Random random = (isUseSeedValueForRandomGenerator()) ?
     new Random(getSeedValueForRandomGenerator()) :
     new Random();

   // get an enumeration of the nodes
   Enumeration nodes = graphModel.getNodes();

   // browse the nodes
   while (nodes.hasMoreElements()) {
     Object node = nodes.nextElement();

     // skip fixed nodes
     if (isPreserveFixedNodes() && isFixed(node))
       continue;

     // compute coordinates
     float x = xMin + (xMax - xMin) * random.nextFloat();
     float y = yMin + (yMax - yMin) * random.nextFloat();

     // move the node to the computed position
     graphModel.moveNode(node, x, y, redraw);

     atLeastOneNodeMoved = true;

     // notify listeners on layout events
     layoutStepPerformed();
   }

   if (atLeastOneNodeMoved)
     layoutReport.setCode(IlvGraphLayoutReport.LAYOUT_DONE);
   else
     layoutReport.setCode(IlvGraphLayoutReport.NO_MOVEABLE_NODE);
 }
 

Note that, beginning with JViews 3.5, the signature of the old method protected abstract void layout() has changed. When writing a new layout algorithm, the method IlvGraphLayout.layout(boolean) must be implemented instead.

Specified by:

layout in class IlvGraphLayout

Parameters:

redraw - If true, the attached graph model will be asked to redraw the graph after layout. When the layout algorithm moves the nodes and reshapes the links, it is required to pass the value of the redraw argument to the methods IlvGraphModel.moveNode(java.lang.Object, float, float, boolean) and IlvGraphModel.reshapeLink(java.lang.Object, ilog.views.IlvPoint, ilog.views.IlvPoint[], int, int, ilog.views.IlvPoint, boolean).

Throws:

IlvGraphLayoutException - If an unusual situation occurs. WARNING: this method can throw one of the subclasses of IlvGraphLayoutException. Specifically, it can throw an IlvInappropriateGraphException. It can also throw an IlvInappropriateLinkException when inappropriate types of links and/or link connectors are used in an IlvGrapher. For details, refer to the documentation of these exception classes.

See Also:

IlvGraphLayout.performLayout(boolean, boolean, boolean), IlvGraphLayout.getLayoutReport(), IlvGraphLayout.layoutStepPerformed(), IlvGraphModel