› Graphviz › Source › Graphviz › Node

class Node

Represents a visual node in the graph, which can be connected to other nodes.

Definitions

def initialize(name, graph = nil, **attributes)

Initialize the node in the graph with the unique name.

Implementation

 
def initialize(name, graph = nil, **attributes)
	@name = name
	@attributes = attributes
	
	@connections = []
	
	# This sets up the connection between the node and the parent.
	@graph = nil
	graph << self if graph
end

def attach(parent)

Attach this node to the given graph:

Implementation

 
def attach(parent)
	@graph = parent
end

attr :name

attr :connections

attr_accessor :attributes

def connect(destination, attributes = {})

Create an edge between this node and the destination with the specified options.

Implementation

 
def connect(destination, attributes = {})
	edge = Edge.new(@graph, self, destination, attributes)
	
	@connections << edge
	
	return edge
end

def connected?(node)

Calculate if this node is connected to another. +O(N)+ search required.

Implementation

 
def connected?(node)
	return @connections.find{|edge| edge.destination == node}
end

def add_node(name = nil, **attributes)

Add a node and #connect to it.

Implementation

 
def add_node(name = nil, **attributes)
	node = @graph.add_node(name, **attributes)
	
	connect(node)
	
	return node
end

def dump_value(value)

Dump the value to dot text format.

Implementation

 
def dump_value(value)
	if Symbol === value
		value.to_s
	else
		value.inspect
	end
end

def dump_attributes(attributes)

Dump the attributes to dot text format.

Implementation

 
def dump_attributes(attributes)
	if attributes.size > 0
		"[" + attributes.collect{|name, value| "#{name}=#{dump_value(value)}"}.join(", ") + "]"
	else
		""
	end
end