y.layout.orthogonal
Class OrthogonalLayouter

java.lang.Object
  y.layout.CanonicMultiStageLayouter
      y.layout.orthogonal.OrthogonalLayouter

All Implemented Interfaces:

Layouter

public class OrthogonalLayouter
extends CanonicMultiStageLayouter

This layout algorithm arranges graphs in an orthogonal fashion.

Layout Style

This layout algorithm arranges the nodes of a given graph such that each edge is drawn as an alternating sequence of horizontal and vertical segments.

It produces compact drawings with no overlapping nodes, few crossings and few bends and is well suited for small and medium-sized sparse graphs.

Orthogonal drawings are common in engineering applications since they are able to provide clear representations of complex networks that can also be optimal with respect to diverse objective functions such as bend minimization or area minimization. Application domains of orthogonal drawings include software engineering, database schema representation, system management, knowledge representation, VLSI circuits and floor planning applications.

Orthogonal layout with default settings

Concept

The orthogonal layout algorithm is based on the topology-shape-metrics approach and runs in three phases:

Planarization

A planar embedding is computed.

Orthogonalization

The bends and the angles are computed.

Compaction

The coordinates for the nodes and edges are determined.

Features

There exist several different layout styles that the orthogonal layout algorithm supports depending on whether or not the edges should be routed completely orthogonal, or whether or not the original size of the nodes should be maintained. Such layout styles are NORMAL_STYLE, UNIFORM_STYLE, BOX_STYLE, MIXED_STYLE, FIXED_BOX_STYLE, FIXED_MIXED_STYLE and can be applied using method setLayoutStyle(int).

OrthogonalLayouter is able to consider edge label data when arranging a graph. This means that the layout algorithm will determine the positions of the nodes and edges such that the edge labels do not overlap with the rest of the layout. Integrated edge labeling can be activated using method setIntegratedEdgeLabelingEnabled(boolean).

EdgeLayoutDescriptor instances can be used for specifying individual information (e.g. distances) for each edge in the graph. The descriptors are bound to the graph using DataProviders registered with key EDGE_LAYOUT_DESCRIPTOR_DPKEY. If there is no descriptor assigned to some edges, a default descriptor will be used. To set default descriptors, use setEdgeLayoutDescriptor(EdgeLayoutDescriptor).

OrthogonalLayouter tries to optimize diverse objective functions such as bend minimization, number of edge crossings, edge length minimization or face maximization. These settings can be enabled using the corresponding methods setPerceivedBendsOptimizationEnabled(boolean), setUseCrossingPostprocessing(boolean), setUseLengthReduction(boolean), and setUseFaceMaximization(boolean), respectively. The drawback when these settings are enabled is that the running time of the algorithm may be drastically increased.

For input graphs without group nodes, this layout algorithm is able to detect some specific substructures. If desired, it can handle and arrange them explicitly, making the structure easy to recognize. Supported substructures are trees, chains and cycles. See the corresponding style properties for details: setTreeStyle(byte), setChainStyle(byte) and setCycleStyle(byte). For the detection of substructures, it is optionally possible to consider node types, such that only nodes of the same user-defined type can form a substructure.

Field Summary

static byte	BOX_STYLE A layout style that modifies the size of nodes to minimize the overall number of bends.
static byte	CHAIN_STYLE_NONE A chain layout style that defines that chains should not be handled specifically.
static byte	CHAIN_STYLE_STRAIGHT A chain layout style that defines that chains are arranged in a straight fashion.
static byte	CHAIN_STYLE_WRAPPED_WITH_BENDS_AT_TURNS A chain layout style that defines that chains are line/column wrapped such that bends of the chain edges form the turns/corners of the chain arrangement.
static byte	CHAIN_STYLE_WRAPPED_WITH_NODES_AT_TURNS A chain layout style that defines that chains are line/column-wrapped such that nodes form the turns/corners of the chain arrangement.
static byte	CYCLE_STYLE_CIRCULAR_WITH_BENDS_AT_CORNERS A cycle layout style that defines that cycle structures are arranged in a circular fashion such that bends of cycle edges form the corners of the circular layout.
static byte	CYCLE_STYLE_CIRCULAR_WITH_NODES_AT_CORNERS A cycle layout style that defines that cycle structures are arranged in a circular fashion such that nodes form the corners of the circular layout.
static byte	CYCLE_STYLE_NONE A cycle layout style that defines that cycles should not be handled specifically.
static java.lang.Object	EDGE_BEND_COST_DPKEY A DataProvider key for providing bend costs for each edge The layout algorithm considers the specified costs during the bend minimization phase.
static java.lang.Object	EDGE_CROSSING_COST_DPKEY A DataProvider key for providing crossing costs for each edge The layout algorithm considers the specified costs during the crossing minimization phase.
static java.lang.Object	EDGE_DIRECTEDNESS_DPKEY A DataProvider key for specifying the directedness of edges for the detection of substructures The edge directedness is considered for the detection of substructures in the input graph i.e., trees, chains and cycles.
static java.lang.Object	EDGE_LAYOUT_DESCRIPTOR_DPKEY A DataProvider key for providing layout information for each edge If no edge layout descriptor is mapped for an edge, a default edge layout descriptor will be obtained using method createEdgeLayoutDescriptor().
static byte	FIXED_BOX_STYLE A layout style similar to BOX_STYLE that maintains the original node size.
static byte	FIXED_MIXED_STYLE A layout style similar to MIXED_STYLE that maintains the original node size.
static byte	MIXED_STYLE A layout style that produces non-orthogonal edges and resizes the nodes to a small uniform size.
static int	NODEMODEL_UNCHANGED Deprecated. Use NORMAL_STYLE instead.
static int	NODEMODEL_UNIFORM Deprecated. Use UNIFORM_STYLE instead.
static byte	NORMAL_STYLE A layout style that produces orthogonal edges while maintaining the original node size.
static byte	NORMAL_TREE_STYLE Deprecated. To configure a style for tree-like structures use the tree style property instead. TREE_STYLE_ASPECT_RATIO_TREE produces tree layouts with a similar style.
static byte	ORIENTATION_AUTO_DETECTION Orientation specifier that defines that the layout orientation of substructures is chosen automatically.
static byte	ORIENTATION_BOTTOM_TO_TOP Orientation specifier that defines that the layout orientation of substructures is bottom to top.
static byte	ORIENTATION_LEFT_TO_RIGHT Orientation specifier that defines that the layout orientation of substructures is left to right.
static byte	ORIENTATION_RIGHT_TO_LEFT Orientation specifier that defines that the layout orientation of substructures is right to left.
static byte	ORIENTATION_TOP_TO_BOTTOM Orientation specifier that defines that the layout orientation of substructures is top to bottom.
static byte	TREE_STYLE_ASPECT_RATIO_TREE A tree layout style that yields tree layouts with an aspect ratio close to 1:1 that are generated by ARNodePlacer.
static byte	TREE_STYLE_COMPACT A tree layout style that aims to create maximally compact layouts for the subtrees by using the CompactNodePlacer for the tree layout algorithm.
static byte	TREE_STYLE_DEFAULT A tree layout style that arranges subtrees in a layered tree fashion with grouped edge routes, generated by a DefaultNodePlacer with routing style DefaultNodePlacer.ROUTING_FORK and alignment setting DefaultNodePlacer.ALIGNMENT_CENTER.
static byte	TREE_STYLE_INTEGRATED A tree layout style that arranges subtrees in a layered tree fashion with grouped edge routes and integrates the tree elements into the orthogonal layout framework.
static byte	TREE_STYLE_NONE A tree layout style that defines that subtrees should not be handled specifically.
static byte	UNIFORM_STYLE A layout style that produces orthogonal edges and nodes of uniform size.

Fields inherited from interface y.layout.Layouter

EDGE_ID_DPKEY, NODE_ID_DPKEY, NODE_TYPE_DPKEY, SELECTED_EDGES, SELECTED_NODES

Constructor Summary

OrthogonalLayouter()
Creates a new OrthogonalLayouter instance with default settings.

Method Summary

boolean	canLayoutCore(LayoutGraph graph) Accepts general graphs without exceptions.
protected EdgeLayoutDescriptor	createEdgeLayoutDescriptor() Returns a new EdgeLayoutDescriptor instance that will be used during the various phases of the layout algorithm to determine the drawing details of the edges of the graph.
void	doLayout(LayoutGraph graph) Calculates an orthogonal layout for the given graph.
void	doLayoutCore(LayoutGraph graph) Calculates an orthogonal layout for the given graph.
int	getChainSize() Returns the minimum size (number of nodes) a chain needs to have to be detected and handled as a chain substructure.
byte	getChainStyle() Returns the chain layout style that defines how chain substructures are arranged.
int	getCycleSize() Returns the minimum size (number of nodes) a cycle needs to have to be detected and explicitly handled as a cycle substructure.
byte	getCycleStyle() Returns the cycle layout style that defines how cycle substructures are arranged.
EdgeLayoutDescriptor	getEdgeLayoutDescriptor() Returns the EdgeLayoutDescriptor instance used for all those edges that do not have a specific layout descriptor assigned.
int	getGrid() Returns the equidistant spacing between the horizontal and vertical grid lines.
int	getLayoutStyle() Returns the layout style for this layout algorithm.
long	getMaximumDuration() Returns the preferred time limit in milliseconds.
int	getNodeModel() Deprecated. Use setLayoutStyle(int) instead.
byte	getTreeOrientation() Returns the desired orientation for subtree layouts.
int	getTreeSize() Returns the minimum size (number of nodes) a subtree needs to have to be detected and explicitly handled as a tree substructure.
byte	getTreeStyle() Returns the tree layout style that defines the basic arrangement style for subtrees.
boolean	getUseCrossingPostprocessing() Returns whether or not the number of edge crossings should be reduced.
boolean	getUseFaceMaximization() Returns whether or not one face of the embedding of the graph should be maximized.
boolean	getUseLengthReduction() Returns whether or not the overall edge length should be optimized.
boolean	getUseRandomization() Returns whether or not a randomization strategy should be performed.
boolean	getUseSketchDrawing() Returns whether or not the existing drawing should be used as a sketch of the resulting orthogonal layout.
boolean	getUseSpacePostprocessing() Deprecated.
boolean	isAlignDegreeOneNodesEnabled() Returns whether or not degree-one nodes that have the same neighbor should be aligned.
boolean	isConsiderNodeLabelsEnabled() Returns whether or not the layout algorithm considers node labels when calculating node positions to avoid overlaps.
boolean	isIntegratedEdgeLabelingEnabled() Returns whether or not the layout algorithm preserves space and places edge labels.
boolean	isParallelRoutesPreferenceEnabled() Returns whether or not parallel routes for parallel edges (multi-edges) are preferred over independent routes.
boolean	isPerceivedBendsOptimizationEnabled() Returns whether or not the number of perceived bends should be minimized.
boolean	isUniformPortAssignmentEnabled() Returns whether or not the layout algorithm should try to obtain a uniform port assignment of the edges incident to the same node side.
void	setAlignDegreeOneNodesEnabled(boolean alignDegreeOneNodesEnabled) Specifies whether or not degree-one nodes that have the same neighbor should be aligned with each other.
void	setChainSize(int chainSize) Specifies the minimum size (number of nodes) a chain needs to have to be detected and handled as a chain substructure.
void	setChainStyle(byte chainStyle) Specifies the chain layout style that defines how chain substructures are arranged.
void	setComponentLayouterEnabled(boolean enabled) Specifies whether or not the LayoutStage used for arranging the components of the graph is activated.
void	setConsiderNodeLabelsEnabled(boolean enabled) Specifies whether or not the layout algorithm considers node labels when calculating node positions to avoid overlaps.
void	setCycleSize(int cycleSize) Specifies the minimum size (number of nodes) a cycle needs to have to be detected and explicitly handled as a cycle substructure.
void	setCycleStyle(byte cycleStyle) Specifies the cycle layout style that defines how cycle substructures are arranged.
void	setEdgeLayoutDescriptor(EdgeLayoutDescriptor edgeLayoutDescriptor) Specifies the EdgeLayoutDescriptor instance used for all those edges that do not have a specific layout descriptor assigned.
void	setGrid(int value) Specifies the equidistant spacing between the horizontal and vertical grid lines.
void	setGroupNodeHidingEnabled(boolean groupNodeHidingEnabled) Specifies whether or not the LayoutStage used for hiding group nodes is activated.
void	setIntegratedEdgeLabelingEnabled(boolean enabled) Specifies whether or not the layout algorithm preserves space and places edge labels.
void	setLayoutStyle(int value) Specifies a layout style for this layout algorithm.
void	setMaximumDuration(long maximumDuration) Specifies the preferred time limit in milliseconds.
void	setNodeModel(int value) Deprecated. Use setLayoutStyle(int) instead.
void	setOrientationLayouterEnabled(boolean enabled) Specifies whether or not the LayoutStage that modifies the orientation of the layout is activated.
void	setParallelRoutesPreferenceEnabled(boolean parallelRoutesPreferenceEnabled) Specifies whether or not parallel routes for parallel edges (multi-edges) are preferred over independent routes.
void	setPerceivedBendsOptimizationEnabled(boolean perceivedBendsOptimizationEnabled) Specifies whether or not the number of perceived bends should be minimized.
void	setTreeOrientation(byte treeOrientation) Specifies the desired orientation for subtree layouts.
void	setTreeSize(int treeSize) Specifies the minimum size (number of nodes) a subtree needs to have to be detected and explicitly handled as a tree substructure.
void	setTreeStyle(byte treeStyle) Specifies the tree layout style that defines the basic arrangement style for subtrees.
void	setUniformPortAssignmentEnabled(boolean uniformPortAssignmentEnabled) Specifies whether or not the layout algorithm should try to obtain a uniform port assignment of the edges incident to the same node side.
void	setUseCrossingPostprocessing(boolean value) Specifies whether or not the number of edge crossings should be reduced.
void	setUseFaceMaximization(boolean value) Specifies whether or not one face of the embedding of the graph should be maximized.
void	setUseLengthReduction(boolean value) Specifies whether or not the overall edge length should be optimized.
void	setUseRandomization(boolean value) Specifies whether or not a randomization strategy should be performed.
void	setUseSketchDrawing(boolean value) Specifies whether or not the existing drawing should be used as a sketch of the resulting orthogonal layout.
void	setUseSpacePostprocessing(boolean value) Deprecated.

Methods inherited from class y.layout.CanonicMultiStageLayouter

appendStage, calcLayout, calcLayout, canLayout, checkGroupNodeSize, checkNodeSize, doLayout, enableOnlyCore, getComponentLayouter, getGroupNodeHider, getLabelLayouter, getLayoutOrientation, getOrientationLayouter, getParallelEdgeLayouter, getSelfLoopLayouter, getSubgraphLayouter, isComponentLayouterEnabled, isGroupNodeHidingEnabled, isLabelLayouterEnabled, isOrientationLayouterEnabled, isParallelEdgeLayouterEnabled, isSelfLoopLayouterEnabled, isSubgraphLayouterEnabled, prependStage, removeStage, setComponentLayouter, setGroupNodeHider, setLabelLayouter, setLabelLayouterEnabled, setLayoutOrientation, setOrientationLayouter, setParallelEdgeLayouter, setParallelEdgeLayouterEnabled, setSelfLoopLayouter, setSelfLoopLayouterEnabled, setSubgraphLayouter, setSubgraphLayouterEnabled

Methods inherited from class java.lang.Object

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

Field Detail

EDGE_LAYOUT_DESCRIPTOR_DPKEY

public static final java.lang.Object EDGE_LAYOUT_DESCRIPTOR_DPKEY

A DataProvider key for providing layout information for each edge

If no edge layout descriptor is mapped for an edge, a default edge layout descriptor will be obtained using method createEdgeLayoutDescriptor().

Minimum edge length constraints can only be considered for layout styles NORMAL_STYLE and UNIFORM_STYLE.

See Also:

setLayoutStyle(int)

EDGE_DIRECTEDNESS_DPKEY

public static final java.lang.Object EDGE_DIRECTEDNESS_DPKEY

A DataProvider key for specifying the directedness of edges for the detection of substructures

The edge directedness is considered for the detection of substructures in the input graph i.e., trees, chains and cycles. A substructure is only identified as such if all edges are either undirected or consistently directed with respect to the specified directedness.

• A directedness value of 1 indicates that the edge is considered to be directed from source to target.
• A directedness value of -1 indicates that the edge is considered to be directed from target to source.
• A directedness value of 0 indicates that the edge is considered to be undirected.

If no DataProvider is registered with this key, all edges are treated as undirected.

EDGE_CROSSING_COST_DPKEY

public static final java.lang.Object EDGE_CROSSING_COST_DPKEY

A DataProvider key for providing crossing costs for each edge

The layout algorithm considers the specified costs during the crossing minimization phase. Edges with lower costs are more likely to have crossings. If no individual costs are defined, each crossing has a cost of 1.

The algorithm uses a heuristic approach for crossing minimization and, thus, doesn't guarantee an optimal solution.

Avoid using very large cost values. Due to the fact that costs need to be multiplied and summed up, this might lead to overflows and undesired results.

EDGE_BEND_COST_DPKEY

public static final java.lang.Object EDGE_BEND_COST_DPKEY

A DataProvider key for providing bend costs for each edge

The layout algorithm considers the specified costs during the bend minimization phase. Edges with lower costs are more likely to have bends. If no individual costs are defined, each bend has a cost of 1.

The algorithm uses a heuristic approach for bend minimization and, thus, doesn't guarantee an optimal solution.

Avoid using very large cost values. Due to the fact that costs need to be multiplied and summed up, this might lead to overflows and undesired results.

NORMAL_STYLE

public static final byte NORMAL_STYLE

A layout style that produces orthogonal edges while maintaining the original node size.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style NORMAL_STYLE

UNIFORM_STYLE

public static final byte UNIFORM_STYLE

A layout style that produces orthogonal edges and nodes of uniform size.

Before calculating the layout, all nodes will be assigned equal sizes.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style UNIFORM_STYLE

BOX_STYLE

public static final byte BOX_STYLE

A layout style that modifies the size of nodes to minimize the overall number of bends.

The layout algorithm will enlarge nodes based on the number and position of their neighbors in order to minimize the number of required bends. The segments of all edges are either horizontal or vertical.

NodeHalos and node labels are not considered when choosing this style. To consider them use NORMAL_STYLE.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style BOX_STYLE

MIXED_STYLE

public static final byte MIXED_STYLE

A layout style that produces non-orthogonal edges and resizes the nodes to a small uniform size.

This layout style resembles BOX_STYLE, but it resizes all nodes to equal size.

It introduces additional bends into some edges and routes the last edge segment of these edges non-orthogonally to their adjacent nodes.

NodeHalos and node labels are not considered when choosing this style. To consider them use NORMAL_STYLE.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style MIXED_STYLE

TREE_STYLE_NONE

public static final byte TREE_STYLE_NONE

A tree layout style that defines that subtrees should not be handled specifically.

Subtrees are not detected and will be arranged without specific emphasis of the tree structure.

See Also:

setTreeStyle(byte), Constant Field Values

Sample Graph:

Tree style TREE_STYLE_NONE

TREE_STYLE_DEFAULT

public static final byte TREE_STYLE_DEFAULT

A tree layout style that arranges subtrees in a layered tree fashion with grouped edge routes, generated by a DefaultNodePlacer with routing style DefaultNodePlacer.ROUTING_FORK and alignment setting DefaultNodePlacer.ALIGNMENT_CENTER.

Child nodes sharing the same parent node are placed next to each other above/below the root (vertical orientation) or above each other left/right of the root (horizontal orientation).

In contrast to TREE_STYLE_INTEGRATED this style produces more compact layout results. However, the overall layout may be less homogeneous because the subtrees are separately arranged by a dedicated tree layout algorithm which does e.g., not consider the specified grid.

See Also:

setTreeStyle(byte), Constant Field Values

Sample Graph:

Tree style TREE_STYLE_DEFAULT

TREE_STYLE_INTEGRATED

public static final byte TREE_STYLE_INTEGRATED

A tree layout style that arranges subtrees in a layered tree fashion with grouped edge routes and integrates the tree elements into the orthogonal layout framework.

Child nodes sharing the same parent node are placed next to each other above/below the root (vertical orientation) or above each other left/right of the root (horizontal orientation).

In contrast to TREE_STYLE_DEFAULT, the subtree elements are handled by the orthogonal layout framework internally. This makes the final layout more homogeneous, but potentially less compact. Furthermore, the grid will be correctly obeyed also for tree nodes.

See Also:

setTreeStyle(byte), Constant Field Values

Sample Graph:

Tree style TREE_STYLE_INTEGRATED

TREE_STYLE_COMPACT

public static final byte TREE_STYLE_COMPACT

A tree layout style that aims to create maximally compact layouts for the subtrees by using the CompactNodePlacer for the tree layout algorithm.

The algorithm applied to the subtrees tries to combine different placement strategies such that the overall area required by subtrees is small. This means that the style of different tree structures can vary within the same layout.

See Also:

setTreeStyle(byte), Constant Field Values

Sample Graph:

Tree style TREE_STYLE_COMPACT

TREE_STYLE_ASPECT_RATIO_TREE

public static final byte TREE_STYLE_ASPECT_RATIO_TREE

A tree layout style that yields tree layouts with an aspect ratio close to 1:1 that are generated by ARNodePlacer.

To achieve the aspect ratio, tree child nodes are organized in as much rows/columns as needed. Edges are routed orthogonally along the rows/columns. The parent node of the children is placed in a corner besides the child nodes depending on the tree layout orientation, e.g., left above the child nodes for top-to-bottom orientation.

See Also:

setTreeStyle(byte), Constant Field Values

Sample Graph:

Tree style TREE_STYLE_ASPECT_RATIO_TREE

ORIENTATION_TOP_TO_BOTTOM

public static final byte ORIENTATION_TOP_TO_BOTTOM

Orientation specifier that defines that the layout orientation of substructures is top to bottom.

See Also:

setTreeOrientation(byte), Constant Field Values

ORIENTATION_BOTTOM_TO_TOP

public static final byte ORIENTATION_BOTTOM_TO_TOP

Orientation specifier that defines that the layout orientation of substructures is bottom to top.

See Also:

setTreeOrientation(byte), Constant Field Values

ORIENTATION_LEFT_TO_RIGHT

public static final byte ORIENTATION_LEFT_TO_RIGHT

Orientation specifier that defines that the layout orientation of substructures is left to right.

See Also:

setTreeOrientation(byte), Constant Field Values

ORIENTATION_RIGHT_TO_LEFT

public static final byte ORIENTATION_RIGHT_TO_LEFT

Orientation specifier that defines that the layout orientation of substructures is right to left.

See Also:

setTreeOrientation(byte), Constant Field Values

ORIENTATION_AUTO_DETECTION

public static final byte ORIENTATION_AUTO_DETECTION

Orientation specifier that defines that the layout orientation of substructures is chosen automatically.

The automatic orientation selection is made e.g., by searching a side at the root node were no edge connects yet and inserting the substructure at that side using the respective orientation (for example, right side means left-to-right layout). It is recommended to use this setting if layouts should be maximally compact, because specifying a fixed orientation reduces the degree of freedom of the algorithm.

See Also:

setTreeOrientation(byte), Constant Field Values

CHAIN_STYLE_NONE

public static final byte CHAIN_STYLE_NONE

A chain layout style that defines that chains should not be handled specifically.

Chains in the input graph are not detected and will be arranged without specific emphasis of the chain structure.

See Also:

setChainStyle(byte), Constant Field Values

Sample Graph:

Chains are not handled explicitly (CHAIN_STYLE_NONE)

CHAIN_STYLE_STRAIGHT

public static final byte CHAIN_STYLE_STRAIGHT

A chain layout style that defines that chains are arranged in a straight fashion.

See Also:

setChainStyle(byte), Constant Field Values

Sample Graph:

Chain layout style CHAIN_STYLE_STRAIGHT

CHAIN_STYLE_WRAPPED_WITH_NODES_AT_TURNS

public static final byte CHAIN_STYLE_WRAPPED_WITH_NODES_AT_TURNS

A chain layout style that defines that chains are line/column-wrapped such that nodes form the turns/corners of the chain arrangement.

See Also:

setChainStyle(byte), Constant Field Values

Sample Graph:

Chain layout style CHAIN_STYLE_WRAPPED_WITH_NODES_AT_TURNS

CHAIN_STYLE_WRAPPED_WITH_BENDS_AT_TURNS

public static final byte CHAIN_STYLE_WRAPPED_WITH_BENDS_AT_TURNS

A chain layout style that defines that chains are line/column wrapped such that bends of the chain edges form the turns/corners of the chain arrangement.

See Also:

setChainStyle(byte), Constant Field Values

Sample Graph:

Chain layout style CHAIN_STYLE_WRAPPED_WITH_BENDS_AT_TURNS

CYCLE_STYLE_NONE

public static final byte CYCLE_STYLE_NONE

A cycle layout style that defines that cycles should not be handled specifically.

Cycles in the input graph are not detected and will be arranged without specific emphasis of the cycle structure.

See Also:

setCycleStyle(byte), Constant Field Values

Sample Graph:

Cycle not handled specifically (CYCLE_STYLE_NONE)

CYCLE_STYLE_CIRCULAR_WITH_NODES_AT_CORNERS

public static final byte CYCLE_STYLE_CIRCULAR_WITH_NODES_AT_CORNERS

A cycle layout style that defines that cycle structures are arranged in a circular fashion such that nodes form the corners of the circular layout.

See Also:

setCycleStyle(byte), Constant Field Values

Sample Graph:

Cycle layout style CYCLE_STYLE_CIRCULAR_WITH_NODES_AT_CORNERS

CYCLE_STYLE_CIRCULAR_WITH_BENDS_AT_CORNERS

public static final byte CYCLE_STYLE_CIRCULAR_WITH_BENDS_AT_CORNERS

A cycle layout style that defines that cycle structures are arranged in a circular fashion such that bends of cycle edges form the corners of the circular layout.

See Also:

setCycleStyle(byte), Constant Field Values

Sample Graph:

Cycle layout style CYCLE_STYLE_CIRCULAR_WITH_BENDS_AT_CORNERS

NORMAL_TREE_STYLE

public static final byte NORMAL_TREE_STYLE

Deprecated. To configure a style for tree-like structures use the tree style property instead. TREE_STYLE_ASPECT_RATIO_TREE produces tree layouts with a similar style.

A layout style similar to NORMAL_STYLE that is best-suited for tree-like structures and graphs that contain one or more subtrees.

The use of this style is not recommended anymore. When specifying this style using setLayoutStyle(int), the tree style is automatically changed to TREE_STYLE_ASPECT_RATIO_TREE, but the layout style value is actually set to NORMAL_STYLE.

See Also:

setTreeStyle(byte), Constant Field Values

FIXED_MIXED_STYLE

public static final byte FIXED_MIXED_STYLE

A layout style similar to MIXED_STYLE that maintains the original node size.

This style introduces additional bends into some edges and routes the last edge segment of these edges non-orthogonally to their adjacent nodes.

NodeHalos and node labels are not considered when choosing this style. To consider them use NORMAL_STYLE.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style FIXED_MIXED_STYLE

FIXED_BOX_STYLE

public static final byte FIXED_BOX_STYLE

A layout style similar to BOX_STYLE that maintains the original node size.

Nodes will be placed at the same positions as with FIXED_MIXED_STYLE, but edges will be routed strictly orthogonally.

NodeHalos and node labels are not considered when choosing this style. To consider them use NORMAL_STYLE.

See Also:

setLayoutStyle(int), Constant Field Values

Sample Graph:

Layout style FIXED_BOX_STYLE

NODEMODEL_UNCHANGED

public static final int NODEMODEL_UNCHANGED

Deprecated. Use NORMAL_STYLE instead.

See Also:

Constant Field Values

NODEMODEL_UNIFORM

public static final int NODEMODEL_UNIFORM

Deprecated. Use UNIFORM_STYLE instead.

See Also:

Constant Field Values

Constructor Detail

OrthogonalLayouter

public OrthogonalLayouter()

Creates a new OrthogonalLayouter instance with default settings.

Method Detail

getMaximumDuration

public long getMaximumDuration()

Returns the preferred time limit in milliseconds.

Depending on the specified value and the size of the input graph, the layout algorithm may automatically disable properties setUseRandomization(boolean), setUseLengthReduction(boolean), setPerceivedBendsOptimizationEnabled(boolean) and setUseCrossingPostprocessing(boolean). These properties improve the layout quality but also increase the runtime, especially for larger graphs. If the time limit is set to Long.MAX_VALUE, the layout algorithm runs unrestricted.

Values have to be greater or equal to 0.

Restricting the maximum duration may result in a lower layout quality. Furthermore, the real runtime may exceed the maximum duration since the layout algorithm still has to find a valid solution.

Returns:

a non-negative value that specifies the preferred time limit

See Also:

setMaximumDuration(long)

setMaximumDuration

public void setMaximumDuration(long maximumDuration)

Specifies the preferred time limit in milliseconds.

Depending on the specified value and the size of the input graph, the layout algorithm may automatically disable properties setUseRandomization(boolean), setUseLengthReduction(boolean), setPerceivedBendsOptimizationEnabled(boolean) and setUseCrossingPostprocessing(boolean). These properties improve the layout quality but also increase the runtime, especially for larger graphs. If the time limit is set to Long.MAX_VALUE, the layout algorithm runs unrestricted.

Values have to be greater or equal to 0.

Restricting the maximum duration may result in a lower layout quality. Furthermore, the real runtime may exceed the maximum duration since the layout algorithm still has to find a valid solution.

Default Value:

The default value is Long.MAX_VALUE. The layout algorithm runs unrestricted.

Parameters:

maximumDuration - a non-negative value that specifies the preferred time limit

Throws:

java.lang.IllegalArgumentException - if the maximum duration is negative

setNodeModel

public void setNodeModel(int value)

Deprecated. Use setLayoutStyle(int) instead.

isUniformPortAssignmentEnabled

public boolean isUniformPortAssignmentEnabled()

Returns whether or not the layout algorithm should try to obtain a uniform port assignment of the edges incident to the same node side.

If this option is enabled, the algorithm may insert additional bends in order to obtain a more uniform port assignment.

If option setUseSketchDrawing(boolean) is enabled, the algorithm doesn't insert additional bends which may result in non-uniform ports even though this option is enabled.

This option can only be considered for layout styles NORMAL_STYLE and UNIFORM_STYLE.

Returns:

true if the port assignment is uniform, false otherwise

See Also:

setUniformPortAssignmentEnabled(boolean)

setUniformPortAssignmentEnabled

public void setUniformPortAssignmentEnabled(boolean uniformPortAssignmentEnabled)

Specifies whether or not the layout algorithm should try to obtain a uniform port assignment of the edges incident to the same node side.

If this option is enabled, the algorithm may insert additional bends in order to obtain a more uniform port assignment.

If option setUseSketchDrawing(boolean) is enabled, the algorithm doesn't insert additional bends which may result in non-uniform ports even though this option is enabled.

This option can only be considered for layout styles NORMAL_STYLE and UNIFORM_STYLE.

Default Value:

The default value is false.

Parameters:

uniformPortAssignmentEnabled - true if the port assignment should be uniform, false otherwise

Sample Graphs:

true

false

getTreeStyle

public byte getTreeStyle()

Returns the tree layout style that defines the basic arrangement style for subtrees.

If there are user-defined node types, a subtree contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

The identified subtrees do never contain parallel edges (multiple edges between the same endpoints).

Returns:

one of the predefined tree styles

See Also:

setTreeStyle(byte)

setTreeStyle

public void setTreeStyle(byte treeStyle)

Specifies the tree layout style that defines the basic arrangement style for subtrees.

If there are user-defined node types, a subtree contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

The identified subtrees do never contain parallel edges (multiple edges between the same endpoints).

Default Value:

The default value is TREE_STYLE_NONE. Subtrees are not arranged in a special way.

Parameters:

treeStyle - one of the predefined tree styles

Throws:

java.lang.IllegalArgumentException - if an unknown tree style is given

getTreeSize

public int getTreeSize()

Returns the minimum size (number of nodes) a subtree needs to have to be detected and explicitly handled as a tree substructure.

This setting has no effect if style TREE_STYLE_NONE is specified.

Returns:

the minimum number of nodes a tree needs to contain to be detected as a substructure

See Also:

setTreeSize(int)

setTreeSize

public void setTreeSize(int treeSize)

Specifies the minimum size (number of nodes) a subtree needs to have to be detected and explicitly handled as a tree substructure.

This setting has no effect if style TREE_STYLE_NONE is specified.

Default Value:

The default value is 3.

Parameters:

treeSize - the minimum number of nodes a tree needs to contain to be detected as a substructure

Throws:

java.lang.IllegalArgumentException - if the given minimum size is less than 3

getTreeOrientation

public byte getTreeOrientation()

Returns the desired orientation for subtree layouts.

This orientation affects only trees that are specifically handled as a tree substructure when the tree style is not TREE_STYLE_NONE. It is independent of the main layout orientation. For example, the main orientation could be top-to-bottom while the subtree orientation is left-to-right at the same time.

This property has no effect if TREE_STYLE_NONE is set as tree style.

Returns:

one of the four default layout orientations or ORIENTATION_AUTO_DETECTION

See Also:

setTreeOrientation(byte)

setTreeOrientation

public void setTreeOrientation(byte treeOrientation)

Specifies the desired orientation for subtree layouts.

This orientation affects only trees that are specifically handled as a tree substructure when the tree style is not TREE_STYLE_NONE. It is independent of the main layout orientation. For example, the main orientation could be top-to-bottom while the subtree orientation is left-to-right at the same time.

This property has no effect if TREE_STYLE_NONE is set as tree style.

Default Value:

The default value is ORIENTATION_AUTO_DETECTION. The tree orientation is determined automatically.

Parameters:

treeOrientation - one of the four default layout orientations or ORIENTATION_AUTO_DETECTION

Throws:

java.lang.IllegalArgumentException - if the given layout orientation is unknown

getChainStyle

public byte getChainStyle()

Returns the chain layout style that defines how chain substructures are arranged.

A chain is a simple edge path where the degree of the nodes is less than or equal to 2.

Property setChainSize(int) defines the minimum length a chain needs to have to be handled explicitly.

If there are user-defined node types, a chain substructure contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

If a chain is part of a handled subtree (tree style other than TREE_STYLE_NONE must be selected), then this chain will be arranged according to the tree layout style and not handled as a chain substructure.

Returns:

one of the predefined chain styles

See Also:

setChainStyle(byte)

setChainStyle

public void setChainStyle(byte chainStyle)

Specifies the chain layout style that defines how chain substructures are arranged.

A chain is a simple edge path where the degree of the nodes is less than or equal to 2.

Property setChainSize(int) defines the minimum length a chain needs to have to be handled explicitly.

If there are user-defined node types, a chain substructure contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

If a chain is part of a handled subtree (tree style other than TREE_STYLE_NONE must be selected), then this chain will be arranged according to the tree layout style and not handled as a chain substructure.

Default Value:

The default value is CHAIN_STYLE_NONE. Chains are not handled explicitly.

Parameters:

chainStyle - one of the predefined chain styles

Throws:

java.lang.IllegalArgumentException - if an unknown chain style is given

getChainSize

public int getChainSize()

Returns the minimum size (number of nodes) a chain needs to have to be detected and handled as a chain substructure.

This setting has no effect if style CHAIN_STYLE_NONE is specified.

Returns:

the minimum number of nodes a chain needs to contain to be detected as a substructure

See Also:

setChainSize(int)

setChainSize

public void setChainSize(int chainSize)

Specifies the minimum size (number of nodes) a chain needs to have to be detected and handled as a chain substructure.

This setting has no effect if style CHAIN_STYLE_NONE is specified.

Default Value:

The default value is 4.

Parameters:

chainSize - the minimum number of nodes a chain needs to contain to be detected as a substructure

Throws:

java.lang.IllegalArgumentException - if the given minimum size is less than 2

getCycleStyle

public byte getCycleStyle()

Returns the cycle layout style that defines how cycle substructures are arranged.

If there are user-defined node types, a cycle contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

A cycle is a simple edge path where the first and last node are identical. The algorithm only considers cycles where at most one edge connects a cycle node with the rest of the graph (i.e. isolated cycles that are connected with one edge).

Returns:

one of the predefined cycle styles

See Also:

setCycleStyle(byte)

setCycleStyle

public void setCycleStyle(byte cycleStyle)

Specifies the cycle layout style that defines how cycle substructures are arranged.

If there are user-defined node types, a cycle contains only nodes of the same type or only nodes without a type (i.e. null as type). This way, node types can be used to control which elements are allowed to form a substructure.

A cycle is a simple edge path where the first and last node are identical. The algorithm only considers cycles where at most one edge connects a cycle node with the rest of the graph (i.e. isolated cycles that are connected with one edge).

Default Value:

The default value is CYCLE_STYLE_NONE. Cycles are not handled explicitly.

Parameters:

cycleStyle - one of the predefined cycle styles

Throws:

java.lang.IllegalArgumentException - if an unknown cycle style is given

getCycleSize

public int getCycleSize()

Returns the minimum size (number of nodes) a cycle needs to have to be detected and explicitly handled as a cycle substructure.

This setting has no effect if style CYCLE_STYLE_NONE is specified.

Returns:

the minimum number of nodes a cycle needs to contain to be detected as a substructure

See Also:

setCycleSize(int)

setCycleSize

public void setCycleSize(int cycleSize)

Specifies the minimum size (number of nodes) a cycle needs to have to be detected and explicitly handled as a cycle substructure.

This setting has no effect if style CYCLE_STYLE_NONE is specified.

Default Value:

The default value is 4.

Parameters:

cycleSize - the minimum number of nodes a cycle needs to contain to be detected as a substructure

Throws:

java.lang.IllegalArgumentException - if the given minimum size is less than 4

isParallelRoutesPreferenceEnabled

public boolean isParallelRoutesPreferenceEnabled()

Returns whether or not parallel routes for parallel edges (multi-edges) are preferred over independent routes.

When enabled, the algorithm routes multi-edges (edges that connect the same pair of nodes) in parallel, i.e., these edges connect to the same side of the nodes and have the same or a similar path. Note that the path is not always exactly the same since the algorithm has to omit label-edge intersections if integrated labeling is enabled. If this setting is disabled, the edges are simply independent and might as well connect to different node sides and get very different paths.

A parallel routing is suitable for a lot of diagrams (especially larger ones) as it helps to better recognize multi-edge structures. However, there are scenarios where the routes of such edges might as well be independent. For small examples the structure can also be clear if the edges connect to other node sides, especially when they are in consecutive order around the node.

This property only affects edges that share the same source and target node.

This setting is ignored when CanonicMultiStageLayouter.isParallelEdgeLayouterEnabled() is enabled, that is, if parallel edges are not handled by this layout algorithm internally but by a specified stage.

Returns:

true if parallel edges are routed in parallel, false otherwise

See Also:

setParallelRoutesPreferenceEnabled(boolean)

setParallelRoutesPreferenceEnabled

public void setParallelRoutesPreferenceEnabled(boolean parallelRoutesPreferenceEnabled)

Specifies whether or not parallel routes for parallel edges (multi-edges) are preferred over independent routes.

When enabled, the algorithm routes multi-edges (edges that connect the same pair of nodes) in parallel, i.e., these edges connect to the same side of the nodes and have the same or a similar path. Note that the path is not always exactly the same since the algorithm has to omit label-edge intersections if integrated labeling is enabled. If this setting is disabled, the edges are simply independent and might as well connect to different node sides and get very different paths.

A parallel routing is suitable for a lot of diagrams (especially larger ones) as it helps to better recognize multi-edge structures. However, there are scenarios where the routes of such edges might as well be independent. For small examples the structure can also be clear if the edges connect to other node sides, especially when they are in consecutive order around the node.

This property only affects edges that share the same source and target node.

This setting is ignored when CanonicMultiStageLayouter.isParallelEdgeLayouterEnabled() is enabled, that is, if parallel edges are not handled by this layout algorithm internally but by a specified stage.

Default Value:

The default value is true. The algorithm tries to route parallel edges in parallel.

Parameters:

parallelRoutesPreferenceEnabled - true if parallel edges should be routed in parallel, false otherwise

Sample Graphs:

true

false

createEdgeLayoutDescriptor

protected EdgeLayoutDescriptor createEdgeLayoutDescriptor()

Returns a new EdgeLayoutDescriptor instance that will be used during the various phases of the layout algorithm to determine the drawing details of the edges of the graph.

This method may be overridden to create a new EdgeLayoutDescriptor instance with different configuration settings.

This method must not return null.

Returns:

a new EdgeLayoutDescriptor instance

getEdgeLayoutDescriptor

public EdgeLayoutDescriptor getEdgeLayoutDescriptor()

Returns the EdgeLayoutDescriptor instance used for all those edges that do not have a specific layout descriptor assigned.

By default, this method will return an EdgeLayoutDescriptor instance created with createEdgeLayoutDescriptor().

Returns:

the current EdgeLayoutDescriptor instance

See Also:

setEdgeLayoutDescriptor(EdgeLayoutDescriptor), EDGE_LAYOUT_DESCRIPTOR_DPKEY

setEdgeLayoutDescriptor

public void setEdgeLayoutDescriptor(EdgeLayoutDescriptor edgeLayoutDescriptor)

Specifies the EdgeLayoutDescriptor instance used for all those edges that do not have a specific layout descriptor assigned.

Default Value:

The default value is EdgeLayoutDescriptor

Parameters:

edgeLayoutDescriptor - the current EdgeLayoutDescriptor instance

Throws:

java.lang.IllegalArgumentException - if the specified EdgeLayoutDescriptor is null

See Also:

EDGE_LAYOUT_DESCRIPTOR_DPKEY

setConsiderNodeLabelsEnabled

public void setConsiderNodeLabelsEnabled(boolean enabled)

Specifies whether or not the layout algorithm considers node labels when calculating node positions to avoid overlaps.

This method is a convenience method that assures that the labeling algorithm is of type LabelLayoutTranslator and LabelLayoutTranslator.setTranslateNodeLabelsEnabled(boolean) is set to true.

Setting this option may overwrite the currently set labeling algorithm. Hence, to combine this option with a generic edge labeling algorithm, the generic labeling has to be applied in an additional step after calculating the layout.

This settings works correctly only in conjunction with layout style NORMAL_STYLE.

Default Value:

The default value is false. Node labels are ignored.

Parameters:

enabled - true if the layout algorithm should take the node labels into account, false otherwise

Sample Graphs:

false

true

isConsiderNodeLabelsEnabled

public boolean isConsiderNodeLabelsEnabled()

Returns whether or not the layout algorithm considers node labels when calculating node positions to avoid overlaps.

This method is a convenience method that assures that the labeling algorithm is of type LabelLayoutTranslator and LabelLayoutTranslator.setTranslateNodeLabelsEnabled(boolean) is set to true.

Setting this option may overwrite the currently set labeling algorithm. Hence, to combine this option with a generic edge labeling algorithm, the generic labeling has to be applied in an additional step after calculating the layout.

This settings works correctly only in conjunction with layout style NORMAL_STYLE.

Returns:

true if the layout algorithm takes the node labels into account, false otherwise

Throws:

java.lang.IllegalStateException - if no properly configured LabelLayoutTranslator is registered even though this property was enabled earlier (can happen when manually specifying the labeling algorithm).

See Also:

setConsiderNodeLabelsEnabled(boolean)

setIntegratedEdgeLabelingEnabled

public void setIntegratedEdgeLabelingEnabled(boolean enabled)

Specifies whether or not the layout algorithm preserves space and places edge labels.

To define the desired placement for each label add a PreferredPlacementDescriptor on EdgeLabelLayout.

This method also assures that the labeling algorithm is of type LabelLayoutTranslator and LabelLayoutTranslator.setTranslateEdgeLabelsEnabled(boolean) is set to true.

When enabling this property, any previously specified labeling algorithm will be overwritten and when disabling it, any currently specified labeling algorithm will be disabled via property CanonicMultiStageLayouter.setLabelLayouterEnabled(boolean). Therefore, it is recommended to only use this convenience property instead of manually changing the mentioned other properties.

Default Value:

The default value is false. Integrated edge labeling is disabled.

Parameters:

enabled - true if integrated edge labeling should be enabled, false otherwise

Sample Graphs:

false

true

isIntegratedEdgeLabelingEnabled

public boolean isIntegratedEdgeLabelingEnabled()

Returns whether or not the layout algorithm preserves space and places edge labels.

To define the desired placement for each label add a PreferredPlacementDescriptor on EdgeLabelLayout.

This method also assures that the labeling algorithm is of type LabelLayoutTranslator and LabelLayoutTranslator.setTranslateEdgeLabelsEnabled(boolean) is set to true.

When enabling this property, any previously specified labeling algorithm will be overwritten and when disabling it, any currently specified labeling algorithm will be disabled via property CanonicMultiStageLayouter.setLabelLayouterEnabled(boolean). Therefore, it is recommended to only use this convenience property instead of manually changing the mentioned other properties.

Returns:

true if integrated edge labeling is enabled, false otherwise

Throws:

java.lang.IllegalStateException - if no properly configured LabelLayoutTranslator is registered even though integrated labeling was enabled earlier (can happen when manually specifying the labeling algorithm).

See Also:

setIntegratedEdgeLabelingEnabled(boolean)

getNodeModel

public int getNodeModel()

Deprecated. Use setLayoutStyle(int) instead.

setUseRandomization

public void setUseRandomization(boolean value)

Specifies whether or not a randomization strategy should be performed.

The randomization will increase the overall layout quality with high probability. The drawback is that the running time of the layout algorithm may increase.

Default Value:

The default value is true. A randomization strategy is applied.

Parameters:

value - true if randomization should be performed, false otherwise

getUseRandomization

public boolean getUseRandomization()

Returns whether or not a randomization strategy should be performed.

The randomization will increase the overall layout quality with high probability. The drawback is that the running time of the layout algorithm may increase.

Returns:

true if randomization is performed, false otherwise

See Also:

setUseRandomization(boolean)

isAlignDegreeOneNodesEnabled

public boolean isAlignDegreeOneNodesEnabled()

Returns whether or not degree-one nodes that have the same neighbor should be aligned.

Returns:

true if the degree-one nodes are aligned, false otherwise

See Also:

setAlignDegreeOneNodesEnabled(boolean)

setAlignDegreeOneNodesEnabled

public void setAlignDegreeOneNodesEnabled(boolean alignDegreeOneNodesEnabled)

Specifies whether or not degree-one nodes that have the same neighbor should be aligned with each other.

Default Value:

The default value is false. Degree-one nodes with the same neighbor are not aligned with each other.

Parameters:

alignDegreeOneNodesEnabled - true if the degree-one nodes should be aligned, false otherwise

Sample Graphs:

false

true

setUseFaceMaximization

public void setUseFaceMaximization(boolean value)

Specifies whether or not one face of the embedding of the graph should be maximized.

An embedding of a graph is uniquely specified by the cyclic order of edges incident to the same node in a graph drawing.

In any planar drawing of a planar graph, the edges divide the plane into different regions called faces. If one of these faces (the outer face) gets maximized, all other faces will be more compact.

Default Value:

The default value is false. No face of the embedding is maximized.

Parameters:

value - true if a face of the embedding of the graph should be maximized, false otherwise

Sample Graphs:

false

true

getUseFaceMaximization

public boolean getUseFaceMaximization()

Returns whether or not one face of the embedding of the graph should be maximized.

An embedding of a graph is uniquely specified by the cyclic order of edges incident to the same node in a graph drawing.

In any planar drawing of a planar graph, the edges divide the plane into different regions called faces. If one of these faces (the outer face) gets maximized, all other faces will be more compact.

Returns:

true if a face of the embedding is maximized, false otherwise

See Also:

setUseRandomization(boolean)

setUseCrossingPostprocessing

public void setUseCrossingPostprocessing(boolean value)

Specifies whether or not the number of edge crossings should be reduced.

The layout algorithm will try to significantly reduce the number of crossings in a post-processing step.

The running time of the layout algorithm may increase.

Default Value:

The default value is true. The number of edge crossings is reduced.

Parameters:

value - true if the number of crossings should be reduced, false otherwise

Sample Graphs:

true

false

getUseCrossingPostprocessing

public boolean getUseCrossingPostprocessing()

Returns whether or not the number of edge crossings should be reduced.

The layout algorithm will try to significantly reduce the number of crossings in a post-processing step.

The running time of the layout algorithm may increase.

Returns:

true if the number of crossings is reduced, false otherwise

See Also:

setUseCrossingPostprocessing(boolean)

isPerceivedBendsOptimizationEnabled

public boolean isPerceivedBendsOptimizationEnabled()

Returns whether or not the number of perceived bends should be minimized.

A perceived bend is not an actual bend but it is created when a helical arrangement of chains of nodes occurs.

Returns:

true if the number of perceived bends is minimized, false otherwise

See Also:

setPerceivedBendsOptimizationEnabled(boolean)

setPerceivedBendsOptimizationEnabled

public void setPerceivedBendsOptimizationEnabled(boolean perceivedBendsOptimizationEnabled)

Specifies whether or not the number of perceived bends should be minimized.

A perceived bend is not an actual bend but it is created when a helical arrangement of chains of nodes occurs.

Default Value:

The default value is false. The number of perceived bends will not be minimized.

Parameters:

perceivedBendsOptimizationEnabled - true if the number of perceived bends should be minimized, false otherwise

Sample Graphs:

false

true

setGrid

public void setGrid(int value)

Specifies the equidistant spacing between the horizontal and vertical grid lines.

Each node will be placed on a grid point. Edges will be routed such that all segments but the first and last one lie on grid lines. (The first and last segments of an edge may or may not lie on grid lines.) Edges consisting of a single segment always lie on grid lines.

The grid spacing has to be greater than 0.

This option is only guaranteed if layout style is NORMAL_STYLE. For all other styles, it is used as a hint only.

Default Value:

The default value is 20.

Parameters:

value - the grid spacing

Throws:

java.lang.IllegalArgumentException - if the grid spacing is negative

Sample Graphs:

Grid spacing 20.

Grid spacing 40.

getGrid

public int getGrid()

Returns the equidistant spacing between the horizontal and vertical grid lines.

Each node will be placed on a grid point. Edges will be routed such that all segments but the first and last one lie on grid lines. (The first and last segments of an edge may or may not lie on grid lines.) Edges consisting of a single segment always lie on grid lines.

The grid spacing has to be greater than 0.

This option is only guaranteed if layout style is NORMAL_STYLE. For all other styles, it is used as a hint only.

Returns:

the grid spacing

See Also:

setGrid(int)

setLayoutStyle

public void setLayoutStyle(int value)

Specifies a layout style for this layout algorithm.

Default Value:

The default value is NORMAL_STYLE

Parameters:

value - one of the predefined layout styles

Throws:

java.lang.IllegalArgumentException - if an unknown layout style is given

getLayoutStyle

public int getLayoutStyle()

Returns the layout style for this layout algorithm.

Returns:

one of the predefined layout styles

See Also:

setLayoutStyle(int)

setUseSpacePostprocessing

public void setUseSpacePostprocessing(boolean value)

Deprecated.

Specifies whether or not the area occupied by the drawing should be minimized.

The layout algorithm will try to reduce significantly the occupied area.

The drawback is that the running time of the layout algorithm may be increased.

Default Value:

The default value is true.

Parameters:

value - true if the drawing area should be minimized, false otherwise

getUseSpacePostprocessing

public boolean getUseSpacePostprocessing()

Deprecated.

Returns whether or not the area occupied by the drawing should be minimized.

The layout algorithm will try to reduce significantly the occupied area.

The drawback is that the running time of the layout algorithm may be increased.

Returns:

true if the drawing area is minimized, false otherwise

See Also:

setUseSpacePostprocessing(boolean)

setUseLengthReduction

public void setUseLengthReduction(boolean value)

Specifies whether or not the overall edge length should be optimized.

The algorithm will try to significantly reduce the length of some edges.

The drawback is that the running time of the layout algorithm may increase.

Default Value:

The default value is true. The overall edge length is reduced.

Parameters:

value - true if the overall edge length should be reduced, false otherwise

Sample Graphs:

true

false

getUseLengthReduction

public boolean getUseLengthReduction()

Returns whether or not the overall edge length should be optimized.

The algorithm will try to significantly reduce the length of some edges.

The drawback is that the running time of the layout algorithm may increase.

Returns:

true if the overall edge length minimization is reduced, false otherwise

See Also:

setUseLengthReduction(boolean)

getUseSketchDrawing

public boolean getUseSketchDrawing()

Returns whether or not the existing drawing should be used as a sketch of the resulting orthogonal layout.

The layout algorithm will try to orthogonalize the given sketch without making too many modifications with respect to the original drawing.

Returns:

true if the existing drawing is used as a sketch, false otherwise

See Also:

setUseSketchDrawing(boolean)

setUseSketchDrawing

public void setUseSketchDrawing(boolean value)

Specifies whether or not the existing drawing should be used as a sketch of the resulting orthogonal layout.

The layout algorithm will try to orthogonalize the given sketch without making too many modifications in respect to the original drawing.

If this option is enabled, the existing drawing should be preserved as much as possible. Hence, optimization steps like setUseCrossingPostprocessing(boolean), setUseFaceMaximization(boolean) and setPerceivedBendsOptimizationEnabled(boolean) are not applied even if enabled.

Default Value:

The default value is false. The initial coordinates of the nodes are not considered.

Parameters:

value - true if the existing drawing should be used as a sketch, false otherwise

Sample Graphs:

Initial drawing

Orthogonal layout when initial drawing is used as sketch

Orthogonal layout when the initial drawing is not used as sketch

setComponentLayouterEnabled

public void setComponentLayouterEnabled(boolean enabled)

Specifies whether or not the LayoutStage used for arranging the components of the graph is activated.

Overrides:

setComponentLayouterEnabled in class CanonicMultiStageLayouter

OrthogonalLayouter can only handle single components. Disabling ComponentLayouter will lead to errors during execution.

Default Value:

The default value is true. The stage that arranges connected graph components is activated.

Parameters:

enabled - true if the stage that arranges the graph components is activated, false otherwise

See Also:

CanonicMultiStageLayouter.isComponentLayouterEnabled(), CanonicMultiStageLayouter.setComponentLayouter(LayoutStage), ComponentLayouter

setGroupNodeHidingEnabled

public void setGroupNodeHidingEnabled(boolean groupNodeHidingEnabled)

Specifies whether or not the LayoutStage used for hiding group nodes is activated.

Overrides:

setGroupNodeHidingEnabled in class CanonicMultiStageLayouter

OrthogonalLayouter cannot handle group nodes. Disabling GroupNodeHider will lead to errors during execution.

Default Value:

The default value is true. The stage responsible for hiding group nodes is activated.

Parameters:

groupNodeHidingEnabled - true if the stage used for hiding group nodes is activated, false otherwise

See Also:

CanonicMultiStageLayouter.isGroupNodeHidingEnabled(), CanonicMultiStageLayouter.setGroupNodeHider(LayoutStage), GroupNodeHider

setOrientationLayouterEnabled

public void setOrientationLayouterEnabled(boolean enabled)

Specifies whether or not the LayoutStage that modifies the orientation of the layout is activated.

Overrides:

setOrientationLayouterEnabled in class CanonicMultiStageLayouter

If the current layout orientation is LayoutOrientation.TOP_TO_BOTTOM, the orientation of the layout will not be modified.

Based on the undirected layout style, disabling OrientationLayouter has no significant effect.

Default Value:

The default value is true. The orientation LayoutStage is activated.

Parameters:

enabled - true if the stage that modifies the orientation is activated, false otherwise

See Also:

CanonicMultiStageLayouter.isOrientationLayouterEnabled(), CanonicMultiStageLayouter.setOrientationLayouter(LayoutStage), CanonicMultiStageLayouter.setLayoutOrientation(byte), OrientationLayouter

canLayoutCore

public boolean canLayoutCore(LayoutGraph graph)

Accepts general graphs without exceptions.

Specified by:

canLayoutCore in class CanonicMultiStageLayouter

Parameters:

graph - the input graph

Returns:

true for all input graphs

doLayoutCore

public void doLayoutCore(LayoutGraph graph)

Calculates an orthogonal layout for the given graph.

Specified by:

doLayoutCore in class CanonicMultiStageLayouter

The given graph will not be copied during the layout process and the result will be immediately applied to the input graph.

Parameters:

graph - the input graph

doLayout

public void doLayout(LayoutGraph graph)

Calculates an orthogonal layout for the given graph.

Specified by:

doLayout in interface Layouter

Overrides:

doLayout in class CanonicMultiStageLayouter

The given graph will not be copied during the layout process and the result will be immediately applied to the input graph.

Parameters:

graph - the input graph

See Also:

CanonicMultiStageLayouter.appendStage(LayoutStage), CanonicMultiStageLayouter.prependStage(LayoutStage), CanonicMultiStageLayouter.doLayoutCore(LayoutGraph)