Package com.macrofocus.treemap

Class PivotByAlgorithm

java.lang.Object

com.macrofocus.treemap.AbstractAlgorithm

com.macrofocus.treemap.PivotByAlgorithm

All Implemented Interfaces:

Algorithm

public class PivotByAlgorithm
extends AbstractAlgorithm

Implementation of the Pivot By algorithm. It is described described in:

Ben Shneiderman and Martin Wattenberg. Ordered treemap layouts. IEEE Symposium on Information Visualization, 0:73, 2001.

Complexity: O(n^2), where n is the number of nodes in the tree (depends on the pivot in use).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PivotByAlgorithm.Biggest	The pivot is taken to be the item with the largest area since the largest item is the most difficult to place.
static class	PivotByAlgorithm.Middle	The pivot is taken to be the middle item of the list since this is more likely to create a balanced layout.
static class	PivotByAlgorithm.SplitSize	Selects the pivot that will split L1 and L3 into approximately equal total areas.
static interface	PivotByAlgorithm.Type	Strategy for determining the node to use as a pivot

Constructor Summary

Constructors

Constructor	Description
PivotByAlgorithm()
PivotByAlgorithm(PivotByAlgorithm.Type type)

Method Summary

Modifier and Type	Method	Description
boolean	breadthFirstLayout(java.awt.Shape shape, MutableTreeMapNode parent, MutableTreeMapNode[] children, double sumSizes, int horizontalVanishingPoint, int verticalVanishingPoint, TreeMapWorker worker)	Arrange the items in the given array to fill the given shape.
boolean	isCompatible(java.awt.Shape shape)	Indicates whether the layout algorithm can handle the given geometry of its parent
java.lang.String	toString()

Methods inherited from class com.macrofocus.treemap.AbstractAlgorithm

depthFirstLayout, finishLayout, getProperties, isChildContained, isColorParent, isRenderingLeafLabelsSupported, isRenderingParentLabelSupported, isSpaceFilling, iterator, startLayout, sum

Methods inherited from class java.lang.Object

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

Constructor Detail

PivotByAlgorithm

public PivotByAlgorithm()

PivotByAlgorithm

public PivotByAlgorithm(PivotByAlgorithm.Type type)

Method Detail

breadthFirstLayout

public boolean breadthFirstLayout(java.awt.Shape shape,
                                  MutableTreeMapNode parent,
                                  MutableTreeMapNode[] children,
                                  double sumSizes,
                                  int horizontalVanishingPoint,
                                  int verticalVanishingPoint,
                                  TreeMapWorker worker)

Arrange the items in the given array to fill the given shape. This is called during the first pass, while traversing the tree top down.

Parameters:

shape - the current rectangle being divided.

parent - the parent node.

children - the items to map.

sumSizes - the size of the parent.

worker - the worker thread

Returns:

true if the layout has been cancelled, false otherwise

isCompatible

public boolean isCompatible(java.awt.Shape shape)

Description copied from interface: Algorithm

Indicates whether the layout algorithm can handle the given geometry of its parent

Parameters:

shape - the geometry of its parent

Returns:

true if it can lay out the children using the specified geometrical shape

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object