prefuse.action.layout.graph
Class SquarifiedTreeMapLayout

java.lang.Object
  prefuse.activity.Activity
      prefuse.action.Action
          prefuse.action.GroupAction
              prefuse.action.layout.Layout
                  prefuse.action.layout.graph.TreeLayout
                      prefuse.action.layout.graph.SquarifiedTreeMapLayout

public class SquarifiedTreeMapLayout
extends TreeLayout

TreeLayout instance computing a TreeMap layout that optimizes for low aspect ratios of visualized tree nodes. TreeMaps are a form of space-filling layout that represents nodes as boxes on the display, with children nodes represented as boxes placed within their parent's box.

This particular algorithm is taken from Bruls, D.M., C. Huizing, and J.J. van Wijk, "Squarified Treemaps" In Data Visualization 2000, Proceedings of the Joint Eurographics and IEEE TCVG Sumposium on Visualization, 2000, pp. 33-42. Available online at: http://www.win.tue.nl/~vanwijk/stm.pdf.

For more information on TreeMaps in general, see http://www.cs.umd.edu/hcil/treemap-history/.

Version:

1.0

Author:

jeffrey heer

Field Summary

static java.lang.String	AREA
static Schema	AREA_SCHEMA

Fields inherited from class prefuse.action.layout.graph.TreeLayout

m_root

Fields inherited from class prefuse.action.layout.Layout

m_anchor, m_bounds, m_bpts, m_insets, m_margin, m_tmpa, m_tmpb

Fields inherited from class prefuse.action.GroupAction

m_group

Fields inherited from class prefuse.action.Action

m_vis

Fields inherited from class prefuse.activity.Activity

DEFAULT_STEP_TIME, INFINITY

Constructor Summary

SquarifiedTreeMapLayout(java.lang.String group)
Creates a new SquarifiedTreeMapLayout with no spacing between parent areas and their enclosed children.

SquarifiedTreeMapLayout(java.lang.String group, double frame)
Creates a new SquarifiedTreeMapLayout with the specified spacing between parent areas and their enclosed children.

Method Summary

double	getFrameWidth() Gets the amount of desired framing space, in pixels, between parent rectangles and their enclosed children.
void	run(double frac) Runs this Action, triggering whatever processing this Action performs.
void	setFrameWidth(double frame) Sets the amount of desired framing space between parent rectangles and their enclosed children.

Methods inherited from class prefuse.action.layout.graph.TreeLayout

getLayoutRoot, setLayoutRoot

Methods inherited from class prefuse.action.layout.Layout

getLayoutAnchor, getLayoutBounds, setLayoutAnchor, setLayoutBounds, setMargin, setX, setY

Methods inherited from class prefuse.action.GroupAction

getGroup, setGroup

Methods inherited from class prefuse.action.Action

getVisualization, run, setVisualization

Methods inherited from class prefuse.activity.Activity

addActivityListener, alwaysRunAfter, cancel, fireActivityCancelled, fireActivityFinished, fireActivityScheduled, fireActivityStarted, fireActivityStepped, getDuration, getNextTime, getPace, getPacingFunction, getStartTime, getStepTime, getStopTime, isEnabled, isRunning, isScheduled, removeActivityListener, run, runAfter, runAt, setDuration, setEnabled, setPacingFunction, setStartTime, setStepTime

Methods inherited from class java.lang.Object

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

Field Detail

AREA

public static final java.lang.String AREA

See Also:

Constant Field Values

AREA_SCHEMA

public static final Schema AREA_SCHEMA

Constructor Detail

SquarifiedTreeMapLayout

public SquarifiedTreeMapLayout(java.lang.String group)

Creates a new SquarifiedTreeMapLayout with no spacing between parent areas and their enclosed children.

Parameters:

group - the data group to layout. Must resolve to a Graph instance.

SquarifiedTreeMapLayout

public SquarifiedTreeMapLayout(java.lang.String group,
                               double frame)

Creates a new SquarifiedTreeMapLayout with the specified spacing between parent areas and their enclosed children.

Parameters:

frame - the amount of desired framing space between parent areas and their enclosed children.

group - the data group to layout. Must resolve to a Graph instance.

Method Detail

setFrameWidth

public void setFrameWidth(double frame)

Sets the amount of desired framing space between parent rectangles and their enclosed children. Use a value of 0 to remove frames altogether. If you adjust the frame value, you must re-run the layout to see the change reflected. Negative frame values are not allowed and will result in an IllegalArgumentException.

Parameters:

frame - the frame width, 0 for no frames

getFrameWidth

public double getFrameWidth()

Gets the amount of desired framing space, in pixels, between parent rectangles and their enclosed children.

Returns:

the frame width

run

public void run(double frac)

Description copied from class: Action

Runs this Action, triggering whatever processing this Action performs. Subclass this method to create custom Actions.

Specified by:

run in class GroupAction

Parameters:

frac - the fraction of this Action's duration that has elapsed.

See Also:

Action.run(double)