X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Ftimeman.cpp;h=051d9726aa9ae29cb6398d00d79db23b090653bc;hp=81c2f39b77e4d40eaff30c57dadeeda6f4f2b1be;hb=be641e881fdfdf3354453381f832fe7822e7c731;hpb=59a9bc93512138eca31ec38d36d8ddd7868ed708

diff --git a/src/timeman.cpp b/src/timeman.cpp
index 81c2f39b..051d9726 100644
--- a/src/timeman.cpp
+++ b/src/timeman.cpp
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -18,6 +18,7 @@
 */
 
 #include <algorithm>
+#include <cfloat>
 #include <cmath>
 
 #include "search.h"
@@ -34,8 +35,6 @@ namespace {
 
   const double xscale     = 9.3;
   const double xshift     = 59.8;
-  const double yscale     = 7780;
-  const double yshift     = 1e-3; // Larger than 0. Ensures a non-zero importance
   const double skewfactor = 0.172;
 
 
@@ -46,7 +45,7 @@ namespace {
 
   double move_importance(int ply) {
 
-    return yscale / pow((1 + exp((ply - xshift) / xscale)), skewfactor) + yshift;
+    return pow((1 + exp((ply - xshift) / xscale)), -skewfactor) + DBL_MIN; // Ensure non-zero
   }
 
 
@@ -61,13 +60,13 @@ namespace {
 
 void TimeManager::pv_instability(double bestMoveChanges) {
 
-  unstablePVExtraTime = int(bestMoveChanges * optimumSearchTime / 1.4);
+  unstablePvFactor = 1 + bestMoveChanges;
 }
 
 
 void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color us)
 {
-  /* We support four different kind of time controls:
+  /* We support four different kinds of time controls:
 
       increment == 0 && movesToGo == 0 means: x basetime  [sudden death!]
       increment == 0 && movesToGo != 0 means: x moves in y minutes
@@ -91,9 +90,9 @@ void TimeManager::init(const Search::LimitsType& limits, int currentPly, Color u
   int minThinkingTime      = Options["Minimum Thinking Time"];
   int slowMover            = Options["Slow Mover"];
 
-  // Initialize all to maximum values but unstablePVExtraTime that is reset
-  unstablePVExtraTime = 0;
-  optimumSearchTime = maximumSearchTime = limits.time[us];
+  // Initialize unstablePvFactor to 1 and search times to maximum values
+  unstablePvFactor = 1;
+  optimumSearchTime = maximumSearchTime = std::max(limits.time[us], minThinkingTime);
 
   // We calculate optimum time usage for different hypothetical "moves to go"-values and choose the
   // minimum of calculated search time values. Usually the greatest hypMTG gives the minimum values.