1GraphViz(3) User Contributed Perl Documentation GraphViz(3)
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6 Tk::GraphViz - Render an interactive GraphViz graph
7
9 use Tk::GraphViz;
10 my $gv = $mw->GraphViz ( qw/-width 300 -height 300/ )
11 ->pack ( qw/-expand yes -fill both/ );
12 $gv->show ( $dotfile );
13
15 The GraphViz widget is derived from Tk::Canvas. It adds the ability to
16 render graphs in the canvas. The graphs can be specified either using
17 the DOT graph-description language, or using via a GraphViz object.
18 When show() is called, the graph is passed to the dot command to
20 generate the layout info. That info is then used to create rectangles,
21 lines, etc in the canvas that reflect the generated layout.
22 Once the items have been created in the graph, they can be used like
24 any normal canvas items: events can be bound, etc. In this way,
25 interactive graphing applications can be created very easily.
26
28 $gv->show ( graph, ?opt => val, ...? )
29 Renders the given graph in the canvas. The graph itself can be
30 specified in a number of formats. 'graph' can be one of the following:
31 - An instance of the GraphViz class (or subclass thereof)
33 - A scalar containing a graph in DOT format. The scalar must match
34 /^\s*(?:di)?graph /.
35 - An instance of the IO::Handle class (or subclass thereof), from which
36 to read a graph in DOT format.
37 - The name / path of a file that contains a graph in DOT format.
38 show() will recognize some options that control how the graph is
40 rendered, etc. The recognized options:
41 layout => CMD
43 Specifies an alternate command to invoke to generate the layout of
44 the graph. If not given, then default is 'dot'. This can be used,
45 for example, to use 'neato' instead of 'dot'.
46 graphattrs => [ name => value, ... ]
48 Allows additional default graph attributes to be specified. Each
49 name => value pair will be passed to dot as '-Gname=value' on the
50 command-line.
51 nodeattrs => [ name => value, ... ]
53 Allows additional default node attributes to be specified. Each
54 name => value pair will be passed to dot as '-Nname=value' on the
55 command-line.
56 edgeattrs => [ name => value, ... ]
58 Allows additional default edge attributes to be specified. Each
59 name => value pair will be passed to dot as '-Ename=value' on the
60 command-line.
61 For example, to use neato to generate a layout with non-overlapping
63 nodes and spline edges:
64 $gv->show ( $file, layout => 'neato',
66 graphattrs => [qw( overlap false spline true )] );
67 $gv->createBindings ( ?option => value? )
69 The Tk::GraphViz canvas can be configured with some bindings for
70 standard operations. If no options are given, the default bindings for
71 zooming and scrolling will be enabled. Alternative bindings can be
72 specified via these options:
73 -zoom => true
75 Creates the default bindings for zooming. Zooming in or out in the
76 canvas will be bound to <Shift-2> (Shift + mouse button 2). To
77 zoom in, click and drag out a zoom rectangle from top left to
78 bottom right. To zoom out, click and drag out a zoom rectangle
79 from bottom left to top right.
80 -zoom => spec
82 This will bind zooming to an alternative event sequence. Examples:
83 -zoom => '<1>' # Zoom on mouse button 1
85 -zoom => '<Ctrl-3>' # Zoom on Ctrl + mouse button 3
86 -scroll => true
88 Creates the default bindings for scrolling / panning. Scrolling
89 the canvas will be bound to <2> (Mouse button 2).
90 -scroll => spec
92 This will bind scrolling to an alternative event sequence.
93 Examples:
94 -scroll => '<1>' # Scroll on mouse button 1
96 -scroll => '<Ctrl-3>' # Scroll on Ctrl + mouse button 3
97 -keypad => true
99 Binds the keypad arrow / number keys to scroll the canvas, and the
100 keypad +/- keys to zoom in and out. Note that the canvas must have
101 the keyboard focus for these bindings to be activated. This is
102 done by default when createBindings() is called without any
103 options.
104 $gv->fit()
106 Scales all of the elements in the canvas to fit the canvas' width and
107 height.
108 $gv->zoom( -in => factor )
110 Zoom in by scaling everything up by the given scale factor. The factor
111 should be > 1.0 in order to get reasonable behavior.
112 $gv->zoom( -out => factor )
114 Zoom out by scaling everything down by the given scale factor. This is
115 equivalent to
116 $gv->zoom ( -in => 1/factor )
118 The factor show be > 1.0 in order to get reasonable behavior.
120
122 In order to facilitate binding, etc, all of the graph elements (nodes,
123 edges, subgraphs) that a created in the cavas. Specific tags are given
124 to each class of element. Additionally, all attributes attached to an
125 element in the graph description (e.g. 'color', 'style') will be
126 included as tags.
127 Nodes
129 Node elements are identified with a 'node' tag. For example, to bind
130 something to all nodes in a graph:
131 $gv->bind ( 'node', '<Any-Enter>', sub { ... } );
133 The value of the 'node' tag is the name of the node in the graph (which
135 is not equivalent to the node label -- that is the 'label' tag)
136 Edges
138 Edge elements are identified with a 'edge' tag. For example, to bind
139 something to all edges in a graph:
140 $gv->bind ( 'edge', '<Any-Enter>', sub { ... } );
142 The value of the 'edge' tag is an a string of the form "node1 node2",
144 where node1 and node2 are the names of the respective nodes. To make
145 it convenient to get the individual node names, the edge also has tags
146 'node1' and 'node2', which give the node names separately.
147 Subgraphs
149 Subgraph elements are identified with a 'subgraph' tag. The value of
150 the 'subgraph' is the name of the subgraph / cluster.
151
153 The following example creates a GraphViz widgets to display a graph
154 from a file specified on the command line. Whenever a node is clicked,
155 the node name and label are printed to stdout:
156 use GraphViz;
158 use Tk;
159 my $mw = new MainWindow ();
161 my $gv = $mw->Scrolled ( 'GraphViz',
162 -background => 'white',
163 -scrollbars => 'sw' )
164 ->pack ( -expand => '1', -fill => 'both' );
165 $gv->bind ( 'node', '<Button-1>', sub {
167 my @tags = $gv->gettags('current');
168 push @tags, undef unless (@tags % 2) == 0;
169 my %tags = @tags;
170 printf ( "Clicked node: '%s' => %s\n",
171 $tags{node}, $tags{label} );
172 } );
173 $gv->show ( shift );
175 MainLoop;
176
178 Lots of DOT language features not yet implemented
179 Various node shapes and attributes: polygon, skew, ...
181 Edge arrow head types
182
184 See http://www.graphviz.org/ for more info on the graphviz tools.
185
187 Jeremy Slade <jeremy@jkslade.net>
188 Other contributors: Mike Castle, John Cerney, Phi Kasten, Jogi
190 Kuenstner Tobias Lorenz, Charles Minc, Reinier Post, Slaven Rezic
191
193 Copyright 2003-2008 by Jeremy Slade
194 This library is free software; you can redistribute it and/or modify it
196 under the same terms as Perl itself.
197
199 Hey! The above document had some coding errors, which are explained
200 below:
201 Around line 2294:
203 You forgot a '=back' before '=head1'
204perl v5.32.0 2020-07-28 GraphViz(3)