The DoubleLayerSubtreePlacer arranges the subtrees of a local root alternating in two layers.
Remarks
Layout Style
This ISubtreePlacer arranges nodes from top to bottom. It places the subtrees in two horizontal layers below the root. They are distributed in an alternating fashion, i.e., adjacent subtrees are in different layers.
This subtree placer is especially useful for leaves with a large width.
Default Values of Properties
| layerSpacingRatio | 0.33 | The distance between the two layers of subtrees is a third of the distance between the root and the upper layer. |
| rootAlignment | TRAILING | |
| spacing | 20 |
Type Details
- yFiles module
- algorithms
See Also
Constructors
Creates a new LeftRightSubtreePlacer instance.
Parameters
A map of options to pass to the method.
- rootAlignment - SubtreeRootAlignment
- The SubtreeRootAlignment that defines how the root node is aligned with its children and their shapes. This option sets the rootAlignment property on the created object.
- layerSpacingRatio - number
- The ratio of the spacing between the root and the children in the upper layer and the spacing between the two layers of subtrees. This option sets the layerSpacingRatio property on the created object.
- transformation - SubtreeTransform
- The modification matrix that defines the direction of the subtree. This option sets the transformation property on the created object.
- alignPorts - boolean
- Whether nodes are placed so that the source and target port of an edge are aligned. This option sets the alignPorts property on the created object.
- spacing - number
- The spacing between subtrees. This option sets the spacing property on the created object.
Properties
Gets or sets whether nodes are placed so that the source and target port of an edge are aligned.
Remarks
Dependent on the SubtreeRootAlignment type the subtree root is moved in a way that the edge connecting the root to one of its children is straightened.
This setting only applies to the following SubtreeRootAlignments:
Default Value
false.Ports are not aligned.
Property Value
true if the ports are to be aligned, false otherwiseSample Graphs
Gets or sets the ratio of the spacing between the root and the children in the upper layer and the spacing between the two layers of subtrees.
Default Value
0.33.The distance between the two layers of subtrees is a third of the distance between the root and the upper layer.
Property Value
Sample Graphs
Gets or sets the SubtreeRootAlignment that defines how the root node is aligned with its children and their shapes.
Default Value
Property Value
Throws
- Exception({ name: 'ArgumentError' })
- if the given root alignment is
null
Gets or sets the spacing between subtrees.
Remarks
Default Value
20.Property Value
Throws
- Exception({ name: 'ArgumentError' })
- if the given spacing is negative
Sample Graphs
Gets the modification matrix that defines the direction of the subtree.
Methods
Creates an edge comparison which takes the initial coordinates of the nodes into account.
Remarks
Returns
- ↪function(LayoutEdge, LayoutEdge):number
- the comparison for the edges
Signature Details
function(x: LayoutEdge, y: LayoutEdge) : numberEncapsulates a method that compares two objects.Parameters
- x - LayoutEdge
- The first object to compare.
- y - LayoutEdge
- The second object to compare.
Returns
- number
- An integer value which is
<0ifxis less thany,0ifxis equal toy, or>0ifxis greater thany
Implements
createProcessor
(treeLayout: TreeLayout, graph: LayoutGraph, currentRoot: LayoutNode) : ISubtreePlacerProcessorCreates an optional ISubtreePlacerProcessor for pre- and post-processing.
Remarks
null.Parameters
A map of options to pass to the method.
- treeLayout - TreeLayout
- the current TreeLayout instance
- graph - LayoutGraph
- the input graph
- currentRoot - LayoutNode
- the root node handled by this ISubtreePlacer
Returns
- ↪ISubtreePlacerProcessor?
- a ISubtreePlacerProcessor instance or
null
Implements
determineChildConnectors
(localRoot: LayoutNode, connectorMap: IMapper<LayoutNode,ParentConnectorDirection>)Provides the direction of the connector to the SubtreeShape for each child node.
Remarks
Parameters
A map of options to pass to the method.
- localRoot - LayoutNode
- the local root node
- connectorMap - IMapper<LayoutNode,ParentConnectorDirection>
- the IMapper<K,V> that is used for storing the direction specifiers of the child nodes
Implements
placeSubtree
(nodeShapeProvider: IMapper<LayoutNode,SubtreeShape>, subtreeShapeProvider: IMapper<LayoutNode,SubtreeShape>, graph: LayoutGraph, localRoot: LayoutNode, parentConnectorDirection: ParentConnectorDirection) : SubtreeShapeArranges the SubtreeShapes of the local root and its children and routes the edges that connect them.
Remarks
This method is the main method of the tree layout algorithm. It is called by TreeLayout in each recursion step to place the local root in relation to its children. Their shapes will be merged into one SubtreeShape, which is returned by this method.
The SubtreeShape for the local root can be obtained from the nodeShapeProvider. subtreeShapeProvider contains the SubtreeShapes assigned to the child nodes.
Due to the order in which the tree nodes are processed, it is guaranteed that at the time of the invocation of this method the SubtreeShape of every descendant node has already been calculated.
Parameters
A map of options to pass to the method.
- nodeShapeProvider - IMapper<LayoutNode,SubtreeShape>
- the IMapper<K,V> for obtaining an initial shape of the root node
- subtreeShapeProvider - IMapper<LayoutNode,SubtreeShape>
- the IMapper<K,V> for accessing the pre-calculated shapes of the subtrees
- graph - LayoutGraph
- the input graph
- localRoot - LayoutNode
- the root of the subtree that should be arranged by this method
- parentConnectorDirection - ParentConnectorDirection
- the direction specifier for the connector of the local root node to its parent node
Returns
- ↪SubtreeShape
- the combined shape of the whole subtree