Don't sleep longer than necessary to meet the interval.

[cellular-automata.git] / 003 / src / life.erl

diff --git a/003/src/life.erl b/003/src/life.erl
index 5f91d26..f4b1fe5 100644 (file)
--- a/003/src/life.erl
+++ b/003/src/life.erl
@@ -7,7 +7,7 @@
 -define(CHAR_ALIVE, 111).  % "o"
 -define(CHAR_BAR,    45).  % "-"
 
--define(INTERVAL, 100).
+-define(GEN_INTERVAL, 100).
 
 
 -record(state, {x            :: non_neg_integer()
@@ -73,7 +73,10 @@ life_loop(
                           ,print_time   = PrintTime
     },
 
-    timer:sleep(?INTERVAL),
+    NewTimeMil = NewTime / 1000,
+    NextGenDelay = round(?GEN_INTERVAL - NewTimeMil),
+    timer:sleep(NextGenDelay),
+
     life_loop(NewState).
 
 
@@ -94,6 +97,9 @@ do_print_status(Bar, X, Y, N, GenCount, TimeMic, PrintTimeMic) ->
 
 
 do_print_board(Board) ->
+    % It seems that just doing a fold should be faster than map + to_list
+    % combo, but, after measuring several times, map + to_list has been
+    % consistently (nearly twice) faster than either foldl or foldr.
     RowStrings = array:to_list(
         array:map(
             fun(_, Row) ->