From 9e0836608220242a2c2b745a0430a7c4b9e33ced Mon Sep 17 00:00:00 2001
From: Michael Stapelberg <michael@stapelberg.de>
Date: Mon, 21 Feb 2011 20:00:56 +0100
Subject: [PATCH] add proof-of-concept perl script to render the tree to SVG

This will be useful to generate examples for the documentation.
---
 render-tree/Con.pm    |  21 +++++++
 render-tree/render.pl | 125 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 render-tree/Con.pm
 create mode 100755 render-tree/render.pl

diff --git a/render-tree/Con.pm b/render-tree/Con.pm
new file mode 100644
index 00000000..1830caf8
--- /dev/null
+++ b/render-tree/Con.pm
@@ -0,0 +1,21 @@
+# vim:ts=4:sw=4:expandtab
+package Con;
+
+use Moose;
+use MooseX::AttributeHelpers;
+use v5.10;
+
+has 'name' => (is => 'ro', isa => 'Str');
+has 'width' => (is => 'rw', isa => 'Int', default => 100);
+has '_nodes' => (is => 'ro', metaclass => 'Collection::Array', isa => 'ArrayRef[Con]',
+    default => sub { [] },
+    provides => {
+        'push' => 'add_node',
+        elements => 'nodes',
+    }
+);
+has 'parent' => (is => 'rw', isa => 'Con', predicate => 'has_parent');
+
+__PACKAGE__->meta->make_immutable;
+
+1
diff --git a/render-tree/render.pl b/render-tree/render.pl
new file mode 100755
index 00000000..bea5811a
--- /dev/null
+++ b/render-tree/render.pl
@@ -0,0 +1,125 @@
+#!/usr/bin/env perl
+# vim:ts=4:sw=4:expandtab
+# © 2011 Michael Stapelberg, see LICENSE
+#
+# Needs SVG (libsvg-perl), IO::All (libio-all-perl), JSON::XS (libjson-xs-perl) and Moose (libmoose-perl)
+#
+# XXX: unfinished proof-of-concept. awaits a json dump in my.tree, renders to test.svg
+# XXX: needs more beautifying (in the SVG but also in the code)
+# XXX: has some rendering differences between firefox and chromium. maybe inkscape makes the file look the same in both browsers
+
+use strict;
+use warnings;
+use SVG;
+use Data::Dumper;
+use JSON::XS;
+use IO::All;
+use List::Util qw(sum);
+use lib qw(.);
+use Con;
+use v5.10;
+
+my $input = io('my.tree')->slurp;
+my $tree = decode_json($input);
+my $root = parse_tree($tree);
+render_tree($root);
+
+sub parse_tree {
+    my ($input, $parent) = @_;
+    my $con = Con->new(name => $input->{name});
+    $con->parent($parent) if defined($parent);
+    for my $node (@{$input->{nodes}}) {
+        $con->add_node(parse_tree($node, $con));
+    }
+
+    return $con;
+}
+
+sub render_tree {
+    my ($con) = @_;
+    say 'rendering con ' . $con->name;
+    my @nodes = $con->nodes;
+    for my $node (@nodes) {
+        render_tree($node);
+    }
+
+    # nothing to calculate when there are no children
+    return unless @nodes > 0;
+
+    $con->width((@nodes > 1 ? (@nodes - 1) * 20 : 0) + sum map { $_->width } @nodes);
+
+    say $con->name . ' has width ' . $con->width;
+}
+
+# TODO: figure out the height
+my $svg = SVG->new(id => "tree", width => $root->width + 5, height => '1052');
+
+my $l1 = $svg->group(id => 'layer1');
+
+# gaussian blur (for drop shadows)
+$svg->defs()->filter(id => 'dropshadow')->fe(-type => 'gaussianblur', stdDeviation => '2.19');
+
+my $idcnt = 0;
+my $y = 10;
+render_svg($root, 0, 0);
+
+sub render_svg {
+    my ($con, $level, $x) = @_;
+
+    my $indent = ' ' x $level;
+
+    say $indent . 'svg-rendering con ' . $con->name . ' on level ' . $level;
+    say $indent . 'width: ' . $con->width;
+
+    # render the dropshadow rect
+    $l1->rect(
+        id => 'outer_rect_shadow' . $idcnt,
+        style => 'opacity:1.0;fill:#000000;fill-opacity:1;stroke:#000000;stroke-width:4;stroke-opacity:1;stroke-miterlimit:4;filter:url(#dropshadow)',
+        width => "96",
+        height => '50',
+        #x => $x + ($con->has_parent ? ($con->parent->width - 100) / 2 : 0),
+        x => $x + ($con->width / 2) - (96 / 2) + 0,
+        y => 4 + $level * 70 + 0,
+    );
+    $idcnt++;
+
+    # render the main rect
+    $l1->rect(
+        id => 'outer_rect' . $idcnt,
+        style => 'opacity:1.0;fill:#c30000;fill-opacity:1;stroke:#000000;stroke-width:4;stroke-opacity:1;stroke-miterlimit:4',
+        width => "96",
+        height => '50',
+        x => $x + ($con->width / 2) - (96 / 2),
+        y => 4 + $level * 70,
+    );
+
+    $idcnt++;
+
+    # render the text
+    $l1->text(
+        style => 'font-size:14px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:left;line-height:125%;letter-spacing:0px;word-spacing:0px;text-anchor:middle;fill:#000000;fill-opacity:1;stroke:none;font-family:Trebuchet MS;-inkscape-font-specification:Trebuchet MS',
+        x => $x + ($con->width / 2) - (100/2) + 5,
+        y => 4 + 15 + $level * 70,
+        id => 'title_'.$idcnt,
+    )->tspan(style => 'text-align:start;text-anchor:start')->cdata($con->name);
+    $idcnt++;
+
+    $y = $y + 50;
+    my @nodes = $con->nodes;
+    my $startx = $x + ($con->width / 2);
+
+    for my $node (@nodes) {
+        render_svg($node, $level + 1, $x);
+        my $mid = $x + ($node->width / 2);
+        $l1->path(
+            d => 'M ' . $startx . ',' . (4 + $level * 70 + 50) . ' ' . $mid . ',' . (4 + ($level+1) * 70),
+            id => 'path' . $idcnt,
+            style => 'fill:none;stroke:#000000;stroke-width:2px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1'
+        );
+        $x += $node->width + 20;
+        $idcnt++;
+    }
+
+}
+
+$svg->render > io('test.svg');