Plot EVE's Regions using Ruby-graphviz

gistfile1.rb

# Include ruby-graphviz in the gemfile

# Doesn't have to be a rake task, obviously.
task draw_regions: :environment do
  require 'graphviz'
  
  # Model initialization left as an exercise to the reader. The models I use are
  # just tables from EVE's static data export.
  regions = StaticData::Region.all.to_a.reject { |r| r.jumps_from.size.zero? }.map { |r| [r.regionID, r]     }.to_h
  jumps   = StaticData::RegionJump.all.to_a.map { |j| [j.fromRegionID, j.toRegionID] }

  regionNodes = {}

  opts_graph = { mode: :graph, layout: :neato, splines: :polyline, overlap: :scalexy, pack: true, smoothing: :spring, compound: true }
  opts_node  = { color: :grey, fillcolor: :yellow, shape: :rect }
  opts_edge  = { arrowhead: :none }

  graph = GraphViz::new(:G, opts_graph) do |graph|

    regions.each do |k, r|
      regionNodes[k] = graph.add_node(r.to_s, opts_node.merge(label: r.to_s))
    end

    jumps.each do |j|
      if j[0].to_i > j[1].to_i
        graph.add_edges(regionNodes[j[0]], regionNodes[j[1]], opts_edge)
      end
    end
  end

  # graph.output(svg: 'output/regions.svg')
  graph.output(png: 'output/regions.png')
end