carnivorous.rb

# Note: If you've been using VMWare recently, it leaves some network
# services dangling. Kill the before you start the sketch:
# sudo killall vmnet-netifup

load_library 'carnivore'
require 'packet_listener'
include Java::PacketListener

def setup
  @nodes            = {}
  @start_diameter   = 150.0
  @min_diameter     = 30.0
  @shrink_speed     = 0.99
  
  smooth
  size 800, 600
  ellipse_mode CENTER
  @carnivore = org.rsg.carnivore.CarnivoreP5.new(self)
end

def draw
  background 255
  @nodes.each do |ip, d|   
     
    # Use last two IP address bytes for x/y coords
    x = ip.split('.')[2].to_i * width / 255.0
    y = ip.split('.')[3].to_i * height / 255.0
    
    stroke 0
    fill 100, 100, 100, 200
    ellipse x, y, d, d
    no_stroke
    fill 100, 100, 100, 50
    ellipse x, y, d + 20, d + 20
    
    @nodes[ip] = (d * @shrink_speed) if d > @min_diameter
  end
end

def packetEvent(p)
  @nodes[p.receiverAddress.ip.to_s] = @start_diameter
  @nodes[p.senderAddress.ip.to_s] = @start_diameter
end