com.yworks.yfiles.layout.hierarchic

Enum LayeringStrategy

java.lang.Object

java.lang.Enum<LayeringStrategy>

com.yworks.yfiles.layout.hierarchic.LayeringStrategy

All Implemented Interfaces:

Serializable, Comparable<LayeringStrategy>

public enum LayeringStrategy
extends Enum<LayeringStrategy>

See Also:

HierarchicLayout.getFromScratchLayeringStrategy()

Enum Constant Summary

Enum Constants

Enum Constant and Description
BFS A layering strategy based on a breadth first search (BFS).
FROM_SKETCH A layering strategy which derives the layers from the initial coordinates of the nodes.
HIERARCHICAL_DOWNSHIFT A layering strategy which applies a fast heuristic that improves the layering done by HIERARCHICAL_TOPMOST by shifting some nodes down.
HIERARCHICAL_OPTIMAL A layering strategy which places each node in the optimal layer to minimize the layer distances.
HIERARCHICAL_TIGHT_TREE A layering strategy which applies a heuristic to approximate the optimal layering.
HIERARCHICAL_TOPMOST A layering strategy which places each node in the highest possible layer without passing its predecessor in the topological order of nodes.
UNKNOWN A dummy layering strategy which describes a strategy that is not part of the default strategies.
USER_DEFINED A layering strategy which uses a layer assignment specified by the user.

Method Summary

Modifier and Type	Method and Description
static LayeringStrategy	fromOrdinal(int ordinal)
int	value()
static LayeringStrategy	valueOf(String name) Returns the enum constant of this type with the specified name.
static LayeringStrategy[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

BFS

public static final LayeringStrategy BFS

A layering strategy based on a breadth first search (BFS).

All edges will span at most one layer in the resulting drawing. Edges between nodes that belong to the same layer are possible.

The nodes that will be placed in the first layer can be provided by a data provider bound to the input graph using the key BFSLayerer.CORE_NODES_DPKEY. If this data provider is not given, then nodes that have no incoming edges are placed in the first layer.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

FROM_SKETCH

public static final LayeringStrategy FROM_SKETCH

A layering strategy which derives the layers from the initial coordinates of the nodes.

It tries to find a layering that is similar to the one in the input graph. The layout algorithm may place nodes in the same layer, even though they are connected by an edge.

In a vertically oriented layout, nodes that overlap vertically are placed in the same layer. The same holds for a horizontally oriented layout in the case where the nodes overlap horizontally.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

HIERARCHICAL_DOWNSHIFT

public static final LayeringStrategy HIERARCHICAL_DOWNSHIFT

A layering strategy which applies a fast heuristic that improves the layering done by HIERARCHICAL_TOPMOST by shifting some nodes down.

The quality of the result is usually worse than the one produced by HIERARCHICAL_TIGHT_TREE.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

HIERARCHICAL_OPTIMAL

public static final LayeringStrategy HIERARCHICAL_OPTIMAL

A layering strategy which places each node in the optimal layer to minimize the layer distances.

The layer distance of an edge is the absolute difference between the layer numbers of its source and target node. The layer assignment will minimize the overall sum of the layer distances of all edges in the layout.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

HIERARCHICAL_TIGHT_TREE

public static final LayeringStrategy HIERARCHICAL_TIGHT_TREE

A layering strategy which applies a heuristic to approximate the optimal layering.

The quality of the result may not be as good as with optimal layering but it is usually achieved faster.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

HIERARCHICAL_TOPMOST

public static final LayeringStrategy HIERARCHICAL_TOPMOST

A layering strategy which places each node in the highest possible layer without passing its predecessor in the topological order of nodes.

All nodes with indegree zero will be assigned to the topmost layer of the layout. The number of separate layers will be as small as possible.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

UNKNOWN

public static final LayeringStrategy UNKNOWN

A dummy layering strategy which describes a strategy that is not part of the default strategies.

See Also:

HierarchicLayout.getFromScratchLayeringStrategy()

USER_DEFINED

public static final LayeringStrategy USER_DEFINED

A layering strategy which uses a layer assignment specified by the user.

The nodes' layer assignment must be provided by a data provider bound to the input graph using the key GivenLayersLayerer.LAYER_ID_DPKEY.

This layering strategy allows edges whose source and target share a layer.

See Also:

HierarchicLayout.setFromScratchLayeringStrategy(LayeringStrategy)

Method Detail

fromOrdinal

public static final LayeringStrategy fromOrdinal(int ordinal)

value

public int value()

valueOf

public static LayeringStrategy valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

values

public static LayeringStrategy[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (LayeringStrategy c : LayeringStrategy.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared