Graph::Easy::Node - Represents a node in a simple graph
use Graph::Easy::Node; my $bonn = Graph::Easy::Node->new('Bonn'); $bonn->set_attribute('border', 'solid 1px black'); my $berlin = Graph::Easy::Node->new( name => 'Berlin' );
A Graph::Easy::Node represents a node in a simple graph. Each node has contents (a text, an image or another graph), and dimension plus an origin. The origin is typically determined by a graph layouter module like Graph::Easy.
Graph::Easy::Node
Apart from the methods of the base class Graph::Easy::Base, a Graph::Easy::Node has the following methods:
Graph::Easy::Base
my $node = Graph::Easy::Node->new( name => 'node name' ); my $node = Graph::Easy::Node->new( 'node name' );
Creates a new node. If you want to add the node to a Graph::Easy object, then please use the following to create the node object:
my $node = $graph->add_node('Node name');
You can then use $node->set_attribute(); or $node->set_attributes(); to set the new Node's attributes.
$node->set_attribute();
$node->set_attributes();
my $ascii = $node->as_ascii();
Return the node as a little box drawn in ASCII art as a string.
my $txt = $node->as_txt();
Return the node in simple txt format, including attributes.
my $svg = $node->as_svg();
Returns the node as Scalable Vector Graphic. The actual code for that routine is defined Graph::Easy::As_svg.pm.
my $txt = $node->as_graphviz_txt();
Returns the node as graphviz compatible text which can be feed to dot etc to create images.
my $txt = $node->as_pure_txt();
Return the node in simple txt format, without the attributes.
my $html = $node->as_html();
Return the node as HTML code.
$node->attribute('border-style');
Returns the respective attribute of the node or undef if it was not set. If there is a default attribute for all nodes of the specific class the node is in, then this will be returned.
my $def = $node->default_attribute('color');
Returns the default value for the given attribute in the class of the object, or the empty string if no default could be found.
my $txt = $node->attributes_as_txt();
Return the attributes of this node as text description.
$node->set_attribute('border-style', 'none');
Sets the specified attribute of this (and only this!) node to the specified value.
$node->del_attribute('border-style');
Deletes the specified attribute of this (and only this!) node.
$node->set_attributes( $hash );
Sets all attributes specified in $hash as key => value pairs in this (and only this!) node.
$hash
my $border = $node->border_attribute();
Assembles the border-width, border-color and border-style attributes into a string like "solid 1px red".
border-width
border-color
border-style
# returns f.i. #ff0000 my $color = $node->get_color_attribute( 'fill' );
Just like get_attribute(), but only for colors, and returns them as hex, using the current colorscheme.
Is an alias to color_attribute().
color_attribute()
my $styles = $node->text_styles(); if ($styles->{'italic'}) { print 'is italic\n'; }
Return a hash with the given text-style properties, aka 'underline', 'bold' etc.
my $grandpa = $node->find_grandparent();
For a node that has no origin (is not relative to another), returns $node. For all others, follows the chain of origin back until a node without a parent is found and returns this node. This code assumes there are no loops, which origin() prevents from happening.
$node
origin()
my $name = $node->name();
Return the name of the node.
my $label = $node->label();
Return the label of the node. If no label was set, returns the name of the node.
name
my $bg = $node->background();
Returns the background color. This method honours group membership and inheritance.
my $title = $node->title();
Returns a potential title that can be used for mouse-over effects. If no title was set (or autogenerated), will return an empty string.
my $link = $node->link();
Returns the URL, build from the linkbase and link (or autolink) attributes. If the node has no link associated with it, return an empty string.
linkbase
link
autolink
my ($w,$h) = $node->dimensions();
Returns the dimensions of the node/cell derived from the label (or name) in characters. Assumes the label/name has literal '\n' replaced by "\n".
my ($cx,$cy) = $node->size();
Returns the node size in cells.
my $contents = $node->contents();
For nested nodes, returns the contents of the node.
my $width = $node->width();
Returns the width of the node. This is a unitless number.
my $height = $node->height();
Returns the height of the node. This is a unitless number.
my $cols = $node->columns();
Returns the number of columns (in cells) that this node occupies.
my $cols = $node->rows();
Returns the number of rows (in cells) that this node occupies.
if ($node->is_multicelled()) { ... }
Returns true if the node consists of more than one cell. See als rows() and cols().
if ($node->is_anon()) { ... }
Returns true if the node is an anonymous node. False for Graph::Easy::Node objects, and true for Graph::Easy::Node::Anon.
Graph::Easy::Node::Anon
my ($x,$y) = $node->pos();
Returns the position of the node. Initially, this is undef, and will be set from Graph::Easy::layout.
Graph::Easy::layout
my ($dx,$dy) = $node->offset();
Returns the position of the node relativ to the origin. Returns (0,0) if the origin node was not sset.
(0,0)
my $x = $node->x();
Returns the X position of the node. Initially, this is undef, and will be set from Graph::Easy::layout.
my $y = $node->y();
Returns the Y position of the node. Initially, this is undef, and will be set from Graph::Easy::layout.
my $id = $node->id();
Returns the node's unique ID number.
$node->grow();
Grows the node in columns() and rows() until all the outgoing/incoming connection fit at the borders.
columns()
rows()
my $cnt = $node->connections();
Returns the number of connections to (incoming) and from (outgoing) this node.
my @pre = $node->predecessors();
Returns all nodes (as objects) that link to us.
if ($node->has_predecessors()) { ... }
Returns true if the node has one or more predecessors. Will return true for nodes with selfloops.
my @suc = $node->successors();
Returns all nodes (as objects) that we are linking to.
my @suc = $node->sorted_successors();
Return successors of the node sorted by their chain value (e.g. successors with more successors first).
my @edges = $node->edges_to($other_node);
Returns all the edge objects that start at $node and go to $other_node.
$other_node
my @edges = $node->shared_edges();
Return a list of all edges starting/ending at this node, that share a port with another edge.
my @nodes = $node->nodes_sharing_start($side, $port);
Return a list of unique nodes that share a start point with an edge from this node, on the specified side (absolut) and port number.
my @nodes = $node->nodes_sharing_end($side, $port);
Return a list of unique nodes that share an end point with an edge from this node, on the specified side (absolut) and port number.
my @edges = $node->edges_to('start', 'south', '0');
Returns all the edge objects that share the same start or end port at the specified side and port number. The side must be one of south, north, west or east. The port number must be positive.
start
end
south
north
west
east
my @edges = $node->incoming();
Return all edges that end at this node.
my @edges = $node->outgoing();
Return all edges that start at this node.
$node->add_to_group( $group );
Put the node into this group.
my $group = $node->group();
Return the group this node belongs to, or undef.
my $parent = $node->parent();
Returns the parent object of the node, which is either the group the node belongs to, or the graph.
my $origin_node = $node->origin();
Returns the node this node is relativ to, or undef otherwise.
$node->relative_to($parent, $dx, $dy);
Sets itself relativ to $parent with the offset $dx,$dy.
$parent
$dx,$dy
my $shape = $node->shape();
Returns the shape of the node as string, defaulting to 'rect'.
my $angle = $self->rotation();
Return the node's rotation, based on the rotate attribute, and in case this is relative, on the node's flow.
rotate
my $flow = $node->flow();
Returns the outgoing flow for this node as absolute direction in degrees.
The value is computed from the incoming flow (or the general flow as default) and the flow attribute of this node.
my $extra_params = $node->_extra_params();
The return value of that method is added as extra params to the HTML tag for a node when as_html() is called. Returns the empty string by default, and can be overriden in subclasses. See also use_class().
use_class()
Overriden method should return a text with a leading space, or the empty string.
Example:
package Graph::Easy::MyNode; use base qw/Graph::Easy::Node/; sub _extra_params { my $self = shift; ' ' . 'onmouseover="alert(\'' . $self->name() . '\');"'; } 1;
None by default.
Graph::Easy.
Copyright (C) 2004 - 2006 by Tels http://bloodgate.com.
See the LICENSE file for more details.
To install Graph::Easy, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Graph::Easy
CPAN shell
perl -MCPAN -e shell install Graph::Easy
For more information on module installation, please visit the detailed CPAN module installation guide.