=head1 DESCRIPTION
Text::Tradition is a library for representation and analysis of collated
-texts, particularly medieval ones. The Collation is the central feature of
-a Tradition, where the text, its sequence of readings, and its relationships
-between readings are actually kept.
+texts, particularly medieval ones. The Stemma is a representation of the
+copying relationships between the witnesses in a Tradition, modelled with
+a connected rooted directed acyclic graph (CRDAG).
=head1 DOT SYNTAX
-The easiest way to define a stemma (which is a directed acyclic graph, denoting
-the scholar's hypothesis concerning which text(s) were copied from which other(s))
-is to use a special form of the 'dot' syntax of GraphViz.
+The easiest way to define a stemma is to use a special form of the 'dot'
+syntax of GraphViz.
Each stemma opens with the line
isa => 'Graph',
predicate => 'has_graph',
);
-
+
sub BUILD {
my( $self, $args ) = @_;
# If we have been handed a dotfile, initialize it into a graph.
sub as_dot {
my( $self, $opts ) = @_;
+ ## See if we are including any a.c. witnesses in this graph.
+ my $graph = $self->graph;
+ if( exists $opts->{'layerwits'} ) {
+ my $extant = {};
+ map { $extant->{$_} = 1 } $self->witnesses;
+ $graph = $self->situation_graph( $extant, $opts->{'layerwits'} );
+ }
+
# Get default and specified options
my %graphopts = (
# 'ratio' => 1,
if $opts->{'node'};
@edgeopts{ keys %{$opts->{'edge'}} } = values %{$opts->{'edge'}}
if $opts->{'edge'};
-
+
my @dotlines;
push( @dotlines, 'digraph stemma {' );
## Print out the global attributes
push( @dotlines, _make_dotline( 'node', %nodeopts ) ) if keys %nodeopts;
# Add each of the nodes.
- foreach my $n ( $self->graph->vertices ) {
- if( $self->graph->has_vertex_attribute( $n, 'label' ) ) {
- my $ltext = $self->graph->get_vertex_attribute( $n, 'label' );
+ foreach my $n ( $graph->vertices ) {
+ if( $graph->has_vertex_attribute( $n, 'label' ) ) {
+ my $ltext = $graph->get_vertex_attribute( $n, 'label' );
push( @dotlines, _make_dotline( $n, 'label' => $ltext ) );
} else {
# Use the default display settings.
+ $n = _dotquote( $n );
push( @dotlines, " $n;" );
}
}
# Add each of our edges.
- foreach my $e ( $self->graph->edges ) {
- my( $from, $to ) = @$e;
+ foreach my $e ( $graph->edges ) {
+ my( $from, $to ) = map { _dotquote( $_ ) } @$e;
push( @dotlines, " $from -> $to;" );
}
push( @dotlines, '}' );
return join( "\n", @dotlines );
}
-=head2 editable
+=head2 editable( $opts )
+
+=head2 editable_graph( $graph, $opts )
+
+Returns a version of the graph rendered in our definition format. The
+output separates statements with a newline; set $opts->{'linesep'} to the
+empty string or to a space if the result is to be sent via JSON.
-Returns a version of the graph rendered in our definition format.
+If a situational version of the stemma is required, the arguments for
+situation_graph should be passed via $opts->{'extant'} and $opts->{'layerwits'}.
=cut
sub editable {
- my $self = shift;
+ my( $self, $opts ) = @_;
+ my $graph = $self->graph;
+ ## See if we need an editable version of a situational graph.
+ if( exists $opts->{'layerwits'} || exists $opts->{'extant'} ) {
+ my $extant = delete $opts->{'extant'} || {};
+ my $layerwits = delete $opts->{'layerwits'} || [];
+ $graph = $self->situation_graph( $extant, $layerwits );
+ }
+ return editable_graph( $graph, $opts );
+}
+
+sub editable_graph {
+ my( $graph, $opts ) = @_;
+
+ # Create the graph
+ my $join = ( $opts && exists $opts->{'linesep'} ) ? $opts->{'linesep'} : "\n";
my @dotlines;
push( @dotlines, 'digraph stemma {' );
my @real; # A cheap sort
- foreach my $n ( sort $self->graph->vertices ) {
- my $c = $self->graph->get_vertex_attribute( $n, 'class' );
+ foreach my $n ( sort $graph->vertices ) {
+ my $c = $graph->get_vertex_attribute( $n, 'class' );
$c = 'extant' unless $c;
if( $c eq 'extant' ) {
push( @real, $n );
foreach my $n ( @real ) {
push( @dotlines, _make_dotline( $n, 'class' => 'extant' ) );
}
- foreach my $e ( sort _by_vertex $self->graph->edges ) {
- my( $from, $to ) = @$e;
+ foreach my $e ( sort _by_vertex $graph->edges ) {
+ my( $from, $to ) = map { _dotquote( $_ ) } @$e;
push( @dotlines, " $from -> $to;" );
}
push( @dotlines, '}' );
- return join( "\n", @dotlines );
+ return join( $join, @dotlines );
}
sub _make_dotline {
my( $obj, %attr ) = @_;
my @pairs;
foreach my $k ( keys %attr ) {
- my $v = $attr{$k};
- $v =~ s/\"/\\\"/g;
- push( @pairs, "$k=\"$v\"" );
+ my $v = _dotquote( $attr{$k} );
+ push( @pairs, "$k=$v" );
}
- return sprintf( " %s [ %s ];", $obj, join( ', ', @pairs ) );
+ return sprintf( " %s [ %s ];", _dotquote( $obj ), join( ', ', @pairs ) );
}
+sub _dotquote {
+ my( $str ) = @_;
+ return $str if $str =~ /^[A-Za-z0-9]+$/;
+ $str =~ s/\"/\\\"/g;
+ $str = '"' . $str . '"';
+ return $str;
+}
+
sub _by_vertex {
return $a->[0].$a->[1] cmp $b->[0].$b->[1];
}
+=head2 situation_graph( $extant, $layered )
+
+Returns a graph which is the original stemma with all witnesses not in the
+%$extant hash marked as hypothetical, and witness layers added to the graph
+according to the list in @$layered. A layered (a.c.) witness is added as a
+parent of its main version, and additionally shares all other parents and
+children with that version.
+
+=cut
+
+sub situation_graph {
+ my( $self, $extant, $layerwits ) = @_;
+
+ my $graph = $self->graph->copy;
+ foreach my $vertex ( $graph->vertices ) {
+ # Set as extant any vertex that is extant in the stemma AND
+ # exists in the $extant hash.
+ my $class = 'hypothetical';
+ $class = 'extant' if exists $extant->{$vertex} && $extant->{$vertex} &&
+ $self->graph->get_vertex_attribute( $vertex, 'class' ) ne 'hypothetical';
+ $graph->set_vertex_attribute( $vertex, 'class', $class );
+ }
+
+ # For each 'layered' witness in the layerwits array, add it to the graph
+ # as an ancestor of the 'main' witness, and otherwise with the same parent/
+ # child links as its main analogue.
+ # TOOD Handle case where B is copied from A but corrected from C
+ my $aclabel = $self->collation->ac_label;
+ foreach my $lw ( @$layerwits ) {
+ # Add the layered witness and set it with the same attributes as
+ # its 'main' analogue
+ throw( "Cannot add a layer to a hypothetical witness $lw" )
+ unless $graph->get_vertex_attribute( $lw, 'class' ) eq 'extant';
+ my $lwac = $lw . $aclabel;
+ $graph->add_vertex( $lwac );
+ $graph->set_vertex_attributes( $lwac,
+ $graph->get_vertex_attributes( $lw ) );
+
+ # Set it as ancestor to the main witness
+ $graph->add_edge( $lwac, $lw );
+
+ # Give it the same ancestors and descendants as the main witness has,
+ # bearing in mind that those ancestors and descendants might also just
+ # have had a layered witness defined.
+ foreach my $v ( $graph->predecessors( $lw ) ) {
+ next if $v eq $lwac; # Don't add a loop
+ $graph->add_edge( $v, $lwac );
+ $graph->add_edge( $v.$aclabel, $lwac )
+ if $graph->has_vertex( $v.$aclabel );
+ }
+ foreach my $v ( $graph->successors( $lw ) ) {
+ next if $v eq $lwac; # but this shouldn't occur
+ $graph->add_edge( $lwac, $v );
+ $graph->add_edge( $lwac, $v.$aclabel )
+ if $graph->has_vertex( $v.$aclabel );
+ }
+ }
+ return $graph;
+}
+
=head2 as_svg
Returns an SVG representation of the graph, calling as_dot first.
my( $self, $opts ) = @_;
my $dot = $self->as_dot( $opts );
my @cmd = qw/dot -Tsvg/;
- my( $svg, $err );
+ my $svg;
my $dotfile = File::Temp->new();
## TODO REMOVE
# $dotfile->unlink_on_destroy(0);
print $dotfile $dot;
push( @cmd, $dotfile->filename );
run( \@cmd, ">", binary(), \$svg );
- $svg = decode_utf8( $svg );
- return $svg;
+ # HACK: Parse the SVG and change the dimensions.
+ # Get rid of width and height attributes to allow scaling.
+ if( $opts->{'size'} ) {
+ require XML::LibXML;
+ my $parser = XML::LibXML->new();
+ my $svgdoc = $parser->parse_string( decode_utf8( $svg ) );
+ my( $ew, $eh ) = @{$opts->{'size'}};
+ # If the graph is wider than it is tall, set width to ew and remove height.
+ # Otherwise set height to eh and remove width.
+ my $width = $svgdoc->documentElement->getAttribute('width');
+ my $height = $svgdoc->documentElement->getAttribute('height');
+ $width =~ s/\D+//g;
+ $height =~ s/\D+//g;
+ my( $remove, $keep, $val );
+ if( $width > $height ) {
+ $remove = 'height';
+ $keep = 'width';
+ $val = $ew . 'px';
+ } else {
+ $remove = 'width';
+ $keep = 'height';
+ $val = $eh . 'px';
+ }
+ $svgdoc->documentElement->removeAttribute( $remove );
+ $svgdoc->documentElement->setAttribute( $keep, $val );
+ $svg = $svgdoc->toString();
+ }
+ # Return the result
+ return decode_utf8( $svg );
}
=head2 witnesses
return @wits;
}
+=head2 hypotheticals
+
+Returns a list of the hypothetical witnesses represented in the stemma.
+
+=cut
+
+sub hypotheticals {
+ my $self = shift;
+ my @wits = grep
+ { $self->graph->get_vertex_attribute( $_, 'class' ) eq 'hypothetical' }
+ $self->graph->vertices;
+ return @wits;
+}
+
sub throw {
Text::Tradition::Error->throw(
'ident' => 'Stemma error',
projects / scpubgit/stemmatology.git / blobdiff