Mersenne-Twister random submodule

Cakefile

@@ -8,6 +8,7 @@ sources = [
   'character.coffee'
   'room.coffee'
   'localize.coffee'
+  'random.coffee'
   'salet.coffee'
 ]
 sourcestring = ""
@@ -24,7 +25,7 @@ task 'build', 'Compile all CoffeeScript files', ->
     fs.mkdirSync 'lib'
 
   # run coffee-script compile
-  exec "coffee -c --no-header -j lib/index.js #{sourcestring}", (err, stdout, stderr) ->
+  exec "cat #{sourcestring} | coffee --compile --stdio --no-header > lib/index.js", (err, stdout, stderr) ->
     if err
       util.log err
       process.exit 1 # abort npm packaging

src/random.coffee

@@ -0,0 +1,183 @@
+###
+This implementation of the Mersenne Twister is a port of the JavaScript
+version by Y. Okada. The JavaScript version was itself a port of a
+C implementation, by Takuji Nishimura and Makoto Matsumoto.
+
+CoffeeScript port by: Jamis Buck <jamis@jamisbuck.org>
+License: Public domain, baby. Knock yourself out.
+
+The original CoffeeScript sources are always available on GitHub:
+http://github.com/jamis/csmazes
+###
+
+class Random
+  N:          624
+  M:          397
+  MATRIX_A:   0x9908b0df
+  UPPER_MASK: 0x80000000
+  LOWER_MASK: 0x7fffffff
+
+  constructor: (seed) ->
+    @mt = new Array(@N)
+    @setSeed seed
+
+  # makes the argument into an unsigned integer, if it is not already one
+  unsigned32: (n1) -> if n1 < 0 then (n1 ^ @UPPER_MASK) + @UPPER_MASK else n1
+
+  # emulates underflow of subtracting two 32-bit unsigned integers. both arguments
+  # must be non-negative 32-bit integers.
+  subtraction32: (n1, n2) ->
+    if n1 < n2
+      @unsigned32((0x100000000 - (n2 - n1)) % 0xffffffff)
+    else
+      n1 - n2
+
+  # emulates overflow of adding two 32-bit integers. both arguments must be
+  # non-negative 32-bit integers.
+  addition32: (n1, n2) -> @unsigned32((n1 + n2) & 0xffffffff)
+
+  # emulates overflow of multiplying two 32-bit integers. both arguments must
+  # be non-negative 32-bit integers.
+  multiplication32: (n1, n2) ->
+    sum = 0
+    for i in [0...32]
+      if ((n1 >>> i) & 0x1)
+        sum = @addition32(sum, @unsigned32(n2 << i))
+    sum
+
+  setSeed: (seed) ->
+    if !seed || typeof seed == "number"
+      @seedWithInteger seed
+    else
+      @seedWithArray seed
+
+  defaultSeed: ->
+    currentDate = new Date()
+    currentDate.getMinutes() * 60000 + currentDate.getSeconds() * 1000 + currentDate.getMilliseconds()
+
+  seedWithInteger: (seed) ->
+    @seed = seed ? @defaultSeed()
+    @mt[0] = @unsigned32(@seed & 0xffffffff)
+    @mti = 1
+
+    while @mti < @N
+      @mt[@mti] = @addition32(
+        @multiplication32(1812433253, @unsigned32(@mt[@mti-1] ^ (@mt[@mti-1] >>> 30))),
+        @mti)
+      @mti[@mti] = @unsigned32(@mt[@mti] & 0xffffffff)
+      @mti++
+
+  seedWithArray: (key) ->
+    @seedWithInteger 19650218
+
+    i = 1
+    j = 0
+    k = if @N > key.length then @N else key.length
+
+    while k > 0
+      _m = @multiplication32(@unsigned32(@mt[i-1] ^ (@mt[i-1] >>> 30)), 1664525)
+      @mt[i] = @addition32(@addition32(@unsigned32(@mt[i] ^ _m), key[j]), j)
+      @mt[i] = @unsigned32(@mt[i] & 0xffffffff)
+
+      i++
+      j++
+
+      if i >= @N
+        @mt[0] = @mt[@N-1]
+        i = 1
+
+      j = 0 if j >= key.length
+      k--
+
+    k = @N - 1
+    while k > 0
+      @mt[i] = @subtraction32(
+        @unsigned32(@mt[i] ^ @multiplication32(@unsigned32(@mt[i-1] ^ (@mt[i-1] >>> 30)), 1566083941)), i)
+      @mt[i] = @unsigned32(@mt[i] & 0xffffffff)
+      i++
+      if i >= @N
+        @mt[0] = @mt[@N-1]
+        i = 1
+
+    @mt[0] = 0x80000000
+
+  nextInteger: (upper) ->
+    return 0 if (upper ? 1) < 1
+
+    mag01 = [0, @MATRIX_A]
+
+    if @mti >= @N
+      kk = 0
+
+      while kk < @N - @M
+        y = @unsigned32((@mt[kk] & @UPPER_MASK) | (@mt[kk+1] & @LOWER_MASK))
+        @mt[kk] = @unsigned32(@mt[kk+@M] ^ (y >>> 1) ^ mag01[y & 0x1])
+        kk++
+
+      while kk < @N-1
+        y = @unsigned32((@mt[kk] & @UPPER_MASK) | (@mt[kk+1] & @LOWER_MASK))
+        @mt[kk] = @unsigned32(@mt[kk+@M-@N] ^ (y >>> 1) ^ mag01[y & 0x1])
+        kk++
+
+      y = @unsigned32((@mt[@N-1] & @UPPER_MASK) | (@mt[0] & @LOWER_MASK))
+      @mt[@N-1] = @unsigned32(@mt[@M-1] ^ (y >>> 1) ^ mag01[y & 0x1])
+      @mti = 0
+
+    y = @mt[@mti++]
+
+    y = @unsigned32(y ^ (y >>> 11))
+    y = @unsigned32(y ^ ((y << 7) & 0x9d2c5680))
+    y = @unsigned32(y ^ ((y << 15) & 0xefc60000))
+
+    @unsigned32(y ^ (y >>> 18)) % (upper ? 0x100000000)
+
+  randomInt: (upper) ->
+    @nextInteger(upper)
+
+  nextFloat: -> @nextInteger() / 0xffffffff
+
+  nextBoolean: -> @nextInteger() % 2 == 0
+  
+  # Returns the result of rolling *n* dice with *dx* sides, and adding *plus*.
+  dice: (n, dx, plus) ->
+    result = 0
+    for i in [0..n]
+      console.log i
+      result += @nextInteger(1, dx)
+    if (plus)
+      result += plus
+    result
+
+  # Rolls dice according to a xdy+z string, where
+  # x and z are optional.
+  # This rolls *x* dice of *y* sides and adds *z* to the result.
+  # The *y* component can be "F" for Fudge die or "%" for percentile.
+
+  diceString: (def) ->
+    diceRe = /^([1-9][0-9]*)?d([%FA]|[1-9][0-9]*)([-+][1-9][0-9]*)?$/;
+    match = def.match(diceRe)
+    if (!match)
+      throw new Error(
+        "dice_string_error".l({string:def})
+      )
+
+    num = 1
+    bonus = 0
+    sides = undefined
+    if match[1]
+      num = parseInt(match[1], 10)
+    if match[3]
+      bonus = parseInt(match[3], 10)
+
+    switch (match[2])
+      when 'F'
+        sides = 3
+        bonus -= num*2
+        break
+      when '%'
+        sides = 100
+        break
+      else
+        sides = parseInt(match[2], 10)
+        break
+    return @dice(num, sides, bonus)

src/salet.coffee

@@ -380,6 +380,8 @@ class Salet
       @progress = saveFile.progress
       @character = new Character
 
+      @rnd = new Random(@progress.seed)
+
       # Start the game
       @init()
 
@@ -414,7 +416,11 @@ class Salet
           console.log "There was an error loading your save. The save will be overwritten."
           console.error err
       else
-        @progress.seed = new Date().toString()
+        currentDate = new Date()
+        @progress.seed = currentDate.getMinutes() * 60000
+        @progress.seed += currentDate.getSeconds() * 1000
+        @progress.seed += currentDate.getMilliseconds()
+        @rnd = new Random(@progress.seed)
 
         @progress.sequence = [{link:@start, when:0}]
 
@@ -444,5 +450,7 @@ class Salet
 
     return this
 
-window.salet = new Salet()
-window.salet.view.init(window.salet)
+salet = new Salet()
+salet.view.init(salet)
+
+module.exports = salet