Provides tree layout style algorithms.

Implementations support radial layout of (sub)trees, compact layout obeying a given aspect ratio, and also horizontal/vertical layout of directed (and undirected) trees.

Class com.yworks.yfiles.layout.tree.GenericTreeLayouter enables the use of com.yworks.yfiles.layout.tree.NodePlacer implementations which are invoked to calculate the subtrees. Predefined node placers that inherit from abstract class com.yworks.yfiles.layout.tree.AbstractRotatableNodePlacer allow for rotation of subtrees.
Note that com.yworks.yfiles.layout.tree.GenericTreeLayouter can be used to emulate the results generated by both com.yworks.yfiles.layout.tree.TreeLayouter and com.yworks.yfiles.layout.tree.HVTreeLayouter .

Related Documentation

See the yFiles FLEX Developer's Guide (Analysis and Layout Part) section on Tree Layout for descriptions of the yFiles tree layout style algorithms.
The section Generic Tree Layout extensively discusses the advanced capabilities of class GenericTreeLayouter and also its numerous NodePlacer implementations.

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	Interface	Description
	FromSketchNodePlacer	A FromSketchNodePlacer is responsible for arranging its nodes using a comparator, which sorts the outgoing edges of a node according to the position of their target nodes in the graph before the actual placement happens.
	NodePlacer	This interface is used by com.yworks.yfiles.layout.tree.GenericTreeLayouter.
	PortAssignment	This interface is used by com.yworks.yfiles.layout.tree.GenericTreeLayouter.
	Processor	A processor is the possibility for each NodePlacer to prepare (and clean up) the graph for its children. It is created within com.yworks.yfiles.layout.tree.NodePlacer.createProcessor() and called by the GenericTreeLayouter at specific positions of the life-cycle. The processor may change the values within the DataMaps for its children.

	Class	Description
	AbstractNodePlacer	Utility class that serves as a basis for implementations of the com.yworks.yfiles.layout.tree.NodePlacer interface.
	AbstractRotatableNodePlacer	This is an abstract base class for NodePlacers that supports rotations. "Supporting rotation" means that the NodePlacers only implement the default direction (e.g.
	AbstractRotatableNodePlacer_Matrix	Instances of this class may be used to configure the com.yworks.yfiles.layout.tree.AbstractRotatableNodePlacer.
	AbstractRotatableNodePlacer_RootAlignment	This class represents the horizontal alignment of the root node.
	ARNodePlacer	This class is used by com.yworks.yfiles.layout.tree.GenericTreeLayouter and implements a sophisticated com.yworks.yfiles.layout.tree.NodePlacer.
	ARTreeLayouter	This tree layouter tries to generate compact tree layouts with a certain aspect ratio.
	AssistantPlacer	The assistant placer is a NodePlacer that delegates the node placement to two different node placers depending on the type of the children. The type of a child is recognized using a DataProvider providing boolean values.
	BalloonLayouter	A tree layouter that lays out the subtrees of the tree in a balloon-like fashion.
	BalloonLayouter_NodeInfo	Encapsulates information bound to a node during the algorithm calculates a layout.
	BusPlacer	The BusPlacer is a special NodePlacer that creates a bus where all child nodes and the root node are connected to. The BusPlacer is rotatable using the constructor 2().
	DefaultNodePlacer	Versatile default implementation of com.yworks.yfiles.layout.tree.NodePlacer used by com.yworks.yfiles.layout.tree.GenericTreeLayouter.
	DefaultPortAssignment	This class provides simple default port assignment strategies.
	DelegatingNodePlacer	The DelegatingNodePlacer may be used to layout the children of the actual node with two different NodePlacers.
	DendrogramPlacer	This is an implementation of the com.yworks.yfiles.layout.tree.NodePlacer interface that can be used to create dendrogram-like tree layouts.
	DoubleLinePlacer	The DoubleLinePlacer is a special node placer that places its children in two lines. This node placer is especially useful for leaves with great width.
	FreePlacer	Placer that can be used as simple "pseudo"-placer.
	GenericTreeLayouter	This class implements the basis of a generic tree layout algorithm.
	GenericTreeLayouter_SubtreeShape	Instances of this class are used to represent the shape of subtrees during the layout.
	GridNodePlacer	This NodePlacer arranges nodes into a grid.
	GroupedNodePlacer	A com.yworks.yfiles.layout.tree.NodePlacer that places the children of a local root in groups.
	HVTreeLayouter	This tree layouter allows to layout a tree such that each subgraph rooted at a node can either have a horizontal or vertical layout.
	LayeredNodePlacer	This NodePlacer calculates and respects layers.
	LeafPlacer	This implementation can be used to "place" leafs.
	LeftRightPlacer	The LeftRightPlacer is a NodePlacer that arranges the Nodes on the left and right side of a vertical bus.
	LeftRightPlacer_LeftRightDataProvider	Utility class providing a method to determine if a given node is aligned left (true) or right (false) to the parent node.
	MultiParentDescriptor	This class is used by com.yworks.yfiles.layout.tree.GenericTreeLayouter to determine the desired layout of nodes that constitute a multi-parent structure.
	NodeOrderComparator	This comparator compares edges by examining the com.yworks.bridge.util.Comparable that is obtained by passing the target nodes (com.yworks.yfiles.base.Edge.target()) to the get method (com.yworks.yfiles.base.DataProvider.getObject()) of the com.yworks.yfiles.base.DataProvider bound to the graph via the NODE_ORDER_DPKEY key.
	NodePlacerCompanion
	SimpleNodePlacer	This is a "default" NodePlacer.
	TreeComponentLayouter	This stage can be used to do mix layouts for tree-like subgraph structures and the non-tree like rest of a graph.
	TreeLayouter	Implementation of a layout algorithm for trees.
	TreeReductionStage	This stage can be used to layout non-tree structures with a tree layout algorithm.
	XCoordComparator	This comparator compares edges by examining the x-coordinates of the centers of their target nodes.