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y.layout
Interface NodeLabelModel

All Known Implementing Classes:
DiscreteNodeLabelModel, EdgeOppositeNodeLabelModel, FreeNodeLabelModel, PortLabelModel, SmartNodeLabelModel, TableGroupNodeRealizer.ColumnNodeLabelModel, TableGroupNodeRealizer.RowNodeLabelModel

public interface NodeLabelModel

NodeLabelModel defines the properties of the model associated with a NodeLabelLayout.

A NodeLabelModel provides a set of possible candidates for the placement of a node label. It also defines a parameter that describes the current location of the label.

It is important that all state information is encapsulated in the model parameter. NodeLabelModel instances may be shared between multiple node labels but produce different parameters for labels with different locations.

 

Method Summary
 java.lang.Object createModelParameter(OrientedRectangle labelBounds, NodeLayout nodeLayout)
          Creates a model parameter that represents the given node label position within this model.
 java.lang.Object getDefaultParameter()
          Returns a model parameter that encodes the default position of this model's allowed node label positions.
 YList getLabelCandidates(NodeLabelLayout labelLayout, NodeLayout nodeLayout)
          Returns all NodeLabelCandidates that describe valid label positions within this model.
 OrientedRectangle getLabelPlacement(YDimension labelSize, NodeLayout nodeLayout, java.lang.Object param)
          Returns the bounds of the label for the position encoded by the given model parameter.
 

Method Detail

getDefaultParameter

java.lang.Object getDefaultParameter()
Returns a model parameter that encodes the default position of this model's allowed node label positions.

This parameter can be passed to getLabelPlacement(YDimension, NodeLayout, Object) to retrieve the corresponding label box.

Returns:
the model parameter describing the default placement of the node label

getLabelPlacement

OrientedRectangle getLabelPlacement(YDimension labelSize,
                                    NodeLayout nodeLayout,
                                    java.lang.Object param)
Returns the bounds of the label for the position encoded by the given model parameter.

 
The provided parameter must have been generated by this model.
Parameters:
labelSize - the width and height of the label
nodeLayout - the layout of the node to which the label belongs
param - the model parameter that describes the abstract position of the label within this model
Returns:
the oriented box of the label

getLabelCandidates

YList getLabelCandidates(NodeLabelLayout labelLayout,
                         NodeLayout nodeLayout)
Returns all NodeLabelCandidates that describe valid label positions within this model.

In case the implementing NodeLabelModel allows every possible location, this method always returns the current location as a LabelCandidate.

Parameters:
labelLayout - the label for which candidates should be generated
nodeLayout - the layout of the node to which the label belongs
Returns:
a list of NodeLabelCandidate instances

createModelParameter

java.lang.Object createModelParameter(OrientedRectangle labelBounds,
                                      NodeLayout nodeLayout)
Creates a model parameter that represents the given node label position within this model.

The created model parameter is the closest parameter representation of the given label location that can be achieved within this model.

This parameter can be passed to getLabelPlacement(YDimension, NodeLayout, Object) to retrieve the current label box.

A model parameter can be an arbitrary Object. However it must contain all information to allow restoring of the encoded location with this NodeLabelModel.

Parameters:
labelBounds - the box of the label, encoding the label location for which the parameter should be created
nodeLayout - the layout of the node to which the label belongs
Returns:
the model parameter representing the given label location
See Also:
getLabelPlacement(YDimension, NodeLayout, Object)

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