Packageflare.vis.operator.layout
Classpublic class TreeMapLayout
InheritanceTreeMapLayout Inheritance Layout Inheritance Operator

Layout that places node in 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 layout determines the area of nodes in the tree map by looking up the sizeField property on leaf nodes. By default, this property is "size", such that the layout will look for size values in the DataSprite.size property.

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/.



Public Properties
 PropertyDefined by
 Inheritedenabled : Boolean
Indicates if the operator is enabled or disabled.
Operator
 InheritedlayoutAnchor : Point
The layout anchor, used by some layout instances to place an initial item or determine a focal point.
Layout
 InheritedlayoutBounds : Rectangle
The layout bounds for the layout.
Layout
 InheritedlayoutRoot : DataSprite
The layout root, the root node for tree layouts.
Layout
 InheritedlayoutType : String = "null"
The type of layout and axes.
Layout
 Inheritedparameters : Object
Sets parameter values for this operator.
Operator
  sizeField : String
The property from which to access size values for leaf nodes.
TreeMapLayout
 Inheritedvisualization : Visualization
The visualization processed by this operator.
Operator
Protected Properties
 PropertyDefined by
 Inherited_anchor : Point
Layout
 Inherited_setAnchor : Boolean = false
Layout
 Inherited_t : Transitioner = null
A transitioner for storing value updates.
Layout
 InheritedxyAxes : CartesianAxes
Returns the visualization's axes as a CartesianAxes instance.
Layout
Public Methods
 MethodDefined by
  
TreeMapLayout(sizeField:String = "size")
Creates a new TreeMapLayout
TreeMapLayout
 Inherited
applyParameters(op:IOperator, params:Object):void
[static] Static method that applies parameter settings to an operator.
Operator
 Inherited
Strips all EdgeSprites in a visualization of any control points.
Layout
 Inherited
Hides the axes.
Layout
 Inherited
operate(t:Transitioner = null):void
Performs an operation over the contents of a visualization.
Layout
 Inherited
setup():void
Setup method invoked whenever this operator's visualization property is set.
Operator
 Inherited
Reveals the axes.
Layout
 Inherited
[static] Updates all edges to be straight lines.
Layout
Protected Methods
 MethodDefined by
 Inherited
autoAnchor():void
Automatically-generate an anchor point.
Layout
  
layout():void
Calculates the spatial layout of visualized items.
TreeMapLayout
 Inherited
minAngle(a1:Number, a2:Number):Number
Returns an angle value that minimizes the angular distance between a reference angle and a target angle.
Layout
Public Constants
 ConstantDefined by
 InheritedCARTESIAN : String = "cartesian"
[static] Constant indicating Cartesian (x, y) coordinates.
Layout
 InheritedPOLAR : String = "polar"
[static] Constant indicating polar (radius, angle) coordinates.
Layout
Property detail
sizeFieldproperty
sizeField:String  [read-write]

The property from which to access size values for leaf nodes.

Implementation
    public function get sizeField():String
    public function set sizeField(value:String):void
Constructor detail
TreeMapLayout()constructor
public function TreeMapLayout(sizeField:String = "size")

Creates a new TreeMapLayout

Parameters
sizeField:String (default = "size") — the data property from which to access the size value for leaf nodes. The default is the "size" property.
Method detail
layout()method
protected override function layout():void

Calculates the spatial layout of visualized items. Layout operators override this method with their layout implementations.