Hi all,

I did the quiz :) I am new to Ruby so any tips are appreciated.

View at

http://curi.us/code/dungeon.html

or below:

# dungeon.rb Version 1.0
# Elliot Temple
# May 31, 2006
#
# This is my first Ruby Quiz entry
#
# For Ruby Quiz #80
# http://rubyquiz.com/quiz80.html
#
# Generates an ASCII dungeon with an evolutionary algorithm. Makes  
random
# changes and calls undo if the evaluate method returns a lower number.
# Continues for a while, then makes sure to get valid output.
#
# It works but could benefit from tuning various numbers and some new  
features
# in the evaluate function. It could also be faster. Sample output at  
bottom.

class Tile
   attr_accessor :x, :y
   @@TileType = Struct.new(:graphic, :frequency, :walkable)
   @@data = {
   :wall => @@TileType.new("#", 250, false),
   :open => @@TileType.new(" ", 120, true),
   :water => @@TileType.new("~", 10, true),
   :stairs_up => @@TileType.new("<", 1, true),
   :stairs_down => @@TileType.new(">", 1, true)
   }
   def initialize x, y, type = :any
     @x = x
     @y = y
     if type == :any
       @type_history = [get_rand_tile]
     else
       @type_history = [type]
     end
   end
   def type
     @type_history.last
   end
   def to_s
     @@data[@type_history.last].graphic
   end
   def get_rand_tile
     total = @@data.inject(0) { |total, pair| total + pair 
[1].frequency }
     @@data.each do |k,v|
       return k if rand(total) < v.frequency
       total -= v.frequency
     end
   end
   def random_change
     @type_history << get_rand_tile
   end
   def undo(n=1)
     n.times do
       @type_history.pop
     end
   end
   def walkable?
     @@data[@type_history.last].walkable
   end
end

class Map
   def initialize(height,width)
     @height = height
     @width = width
     @map = []
     @changeable_tiles = []
     @last_changed = []
     width.times do |i|
       column = []
       height.times do |j|
         if (j == 0) or (j == width - 1) or (i == 0) or (i == width - 1)
           column << Tile.new(i, j, :wall)
         else
           tmp = Tile.new(i, j)
           column << tmp
           @changeable_tiles << tmp
         end
       end
       @map << column
     end
     @changeable_tiles = @changeable_tiles.sort_by {rand}
     # x = @changeable_tiles.shift
     # x.become_stairs_up
     # x = @changeable_tiles.shift
     # x.become_stairs_down
   end
   def to_s
     # old version that put # around the output
     # '#' * (@width+2) + "\n" + (@map.collect { |row| '#' +  
row.collect {|tile| tile.to_s}.join("") + '#' }.join "\n") + "\n" +  
'#' * (@width+2)
     @map.collect { |row| row.collect {|tile| tile.to_s}.join 
("") }.join "\n"
   end

   def update n=1
     n.times do
       x = @changeable_tiles[rand(@changeable_tiles.length)]
       x.random_change
       @last_changed << x
     end
   end

   def undo n=1
     n.times do
       @last_changed.pop.undo
     end
   end

   def path_between start, destination, exclude = []
     return false if start.nil?
     return true if start == destination
     return false unless start.walkable?
     return false if exclude.include?(start)
     exclude << start
     path_between(self.down(start), destination, exclude) or  
path_between(self.up(start), destination, exclude) or path_between 
(self.left(start), destination, exclude) or path_between(self.right 
(start), destination, exclude)
   end

   def path_between2 start, destination
     g = find_group(start)
     g.include?(destination)
   end

   def find_group start, walkable = true, group = []
     return group if start.nil?
     return group unless start.walkable? == walkable
     return group if group.include?(start)
     group << start
     find_group(self.down(start), walkable, group)
     find_group(self.up(start), walkable, group)
     find_group(self.left(start), walkable, group)
     find_group(self.right(start), walkable, group)
     return group
   end

   def count_groups walkable = true
     tiles = @map.flatten.select { |tile| tile.walkable? == walkable }
     count = 0
     while tiles.any?
       count += 1
       tiles -= find_group(tiles[0], walkable)
     end
     count
   end

   def left tile
     @map[tile.x - 1][tile.y] rescue nil
   end
   def right tile
     @map[tile.x + 1][tile.y] rescue nil
   end
   def down tile
     @map[tile.x][tile.y - 1] rescue nil
   end
   def up tile
     @map[tile.x][tile.y + 1] rescue nil
   end

   def stair_distance
     (find_one(:stairs_up).x - find_one(:stairs_down).x).abs +  
(find_one(:stairs_up).y - find_one(:stairs_down).y).abs
   end

   def find_one tile_type
     @map.flatten.detect {|tile| tile_type == tile.type}
   end

   def number_of tile_type
     @map.flatten.inject(0) do |total, tile|
       tile.type == tile_type ? total + 1 : total
     end
   end

   def valid?
     return false unless number_of(:stairs_up) == 1
     return false unless number_of(:stairs_down) == 1
     return false unless path_between(find_one(:stairs_up), find_one 
(:stairs_down))
     true
   end

   def evaluate
     score = 0
     score -= 200 unless valid?
     if (number_of(:stairs_up) == 1) && (number_of(:stairs_down) == 1)
       score += 200 * stair_distance
     end
     score -= 100 * count_groups(true)
     score -= 70 * count_groups(false)
   end
end

map = Map.new 15,15

tmp = map.to_s
map.update 50
map.undo 40
map.update 50
map.undo 60
raise "undo bug" unless tmp == map.to_s

valid_steps = 0
e = map.evaluate
n = 25
undos = 0

2000.times do
   map.update n
   if map.evaluate >= e
     e = map.evaluate
   else
     map.undo n
     undos += 1
   end
end

until map.valid?
   map.update 1
   valid_steps += 1
end

puts map
puts "steps to validate #{valid_steps}"
puts "undos #{undos}"
puts "stair distance is #{map.stair_distance}"
puts map.count_groups
puts map.count_groups(false)
puts map.evaluate

=begin
Sample Output:

###############
## #####   ## #
## ## ## ### ##
#  #         ##
## > ## #######
##  ##  #######
####### ## # ##
### ### ##    #
###  ##     # #
#   #### #~~###
### #### ##  ##
####~     #####
##### #  #### #
#    <## ######
###############
steps to validate 0
undos 1959
stair distance is 11
4
1
1730
=end

-- Elliot Temple
http://www.curi.us/blog/