1 files changed, 108 insertions, 0 deletions
diff --git a/module/tex/context/third/simpleslides/automata/automata-eca.lua b/module/tex/context/third/simpleslides/automata/automata-eca.lua
new file mode 100644
index 0000000..95d1f71
--- /dev/null
+++ b/module/tex/context/third/simpleslides/automata/automata-eca.lua
@@ -0,0 +1,108 @@
+--
+--------------------------------------------------------------------------------
+--         FILE:  automata-eca.lua
+--  DESCRIPTION:  drawing elementary cellular automata
+-- REQUIREMENTS:  ConTeXt MkIV with Simple Slides module
+--         BUGS:  uncountable
+--       AUTHOR:  Philipp Gesang (Phg), <megas.kapaneus@gmail.com>
+--      VERSION:  1.0
+--      CREATED:  14/08/10 19:43:35 CEST
+--------------------------------------------------------------------------------
+--
+
+environment.loadluafile( "automata-life" )
+
+local help = gol.helpers
+
+local C, Cs, Ct, P, R, S, match = lpeg.C, lpeg.Cs, lpeg.Ct, lpeg.P, lpeg.R, lpeg.S, lpeg.match
+
+
+eca = {}
+
+
+function eca.parse_file (fname)
+    local f = assert(io.open(fname, "r"), "No such file: "..fname..".")
+    local init = f:read("*all")
+    f:close()
+
+    return help.strip(init)
+end
+
+function eca.to_base(number, base)
+    local alphabet, result, cnt, remainder = "0123456789abcdef", "", 0                   
+    while number > 0 do
+        cnt = cnt + 1 
+        number, remainder = math.floor(number / base), (number % base) + 1 
+        result = string.sub(alphabet, remainder, remainder) .. result
+    end 
+    return result
+end
+
+function eca.gen_rule(nr)
+    local rules = {}
+    local states = { "111", "110", "101", "100", "011", "010", "001", "000" }
+    
+    nr = string.format("%8s",eca.to_base(nr, 2)):gsub(" ", "0")
+
+    local n = 1
+    while n <= #states  do
+        rules[states[n]] = nr:sub(n,n)
+        n = n + 1
+    end
+
+    return rules
+end
+
+function eca.next_line(from, rule)
+    local new = ""
+    from = "0"..from.."0"  -- assume dead borders
+    --from = string.format("0%s0", from) -- too slow
+
+    local cell = C(S"01")
+    local cells= Ct(cell * #(cell * cell)) / function (t)
+        local three = t[1]..t[2]..t[3]
+        new = new .. rule[three]
+    end
+    lpeg.match(cells^1, from)
+    return new
+end
+
+function eca.stripcells (str, dir, cnt)
+    if     dir == "left"  then
+        return str:sub( cnt )
+    elseif dir == "right" then
+        return str:sub( 0, str:len() - cnt )
+    else -- assume ambilateral clipping
+        return str:sub( cnt, str:len() - cnt )
+    end
+end
+
+function eca.gen_frame(from, lines, rule)
+
+    local cnt = 1
+    local c = mplife.setup.current
+
+    local new = { [1] = eca.stripcells(from, c.clip, c.diff ) }
+
+    repeat
+        from = eca.next_line(from, rule)
+        table.insert( new, eca.stripcells(from, c.clip, c.diff) )
+        cnt = cnt + 1
+    until cnt == lines
+    return eca.next_line(from, rule), new
+end
+
+function eca.successive (current)
+    local thisframe
+    current.from, thisframe = eca.gen_frame(current.from, current.framesize, current.rule)
+    if not context then -- cli invocation
+        for _,j in ipairs(thisframe) do 
+            io.write(j:gsub("0","·"):gsub("1","O").."\n") 
+        end
+    else
+        
+    end
+    return 0
+end
+
+return eca