Consolidate to centipawns conversion

[stockfish] / src / uci.cpp

diff --git a/src/uci.cpp b/src/uci.cpp
index 523d551e0c051cee5578e951bb70cce4d553e0e0..f893bd9cece7becbc36f38c15ef4155386f07a4e 100644 (file)
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -207,8 +207,8 @@ namespace {
      // The coefficients of a third-order polynomial fit is based on the fishtest data
      // for two parameters that need to transform eval to the argument of a logistic
      // function.
-     constexpr double as[] = {   1.07390458,   -6.94334517,   31.95090161,  317.75424048};
-     constexpr double bs[] = {  -2.82843814,   16.64518180,  -19.74439200,   68.39499088 };
+     constexpr double as[] = {   0.38036525,   -2.82015070,   23.17882135,  307.36768407};
+     constexpr double bs[] = {  -2.29434733,   13.27689788,  -14.26828904,   63.45318330 };
 
      // Enforce that NormalizeToPawnValue corresponds to a 50% win rate at ply 64
      static_assert(UCI::NormalizeToPawnValue == int(as[0] + as[1] + as[2] + as[3]));
@@ -303,6 +303,13 @@ void UCI::loop(int argc, char* argv[]) {
 }
 
 
+/// Turns a Value to an integer centipawn number,
+/// without treatment of mate and similar special scores.
+int UCI::to_cp(Value v) {
+
+  return 100 * v / UCI::NormalizeToPawnValue;
+}
+
 /// UCI::value() converts a Value to a string by adhering to the UCI protocol specification:
 ///
 /// cp <x>    The score from the engine's point of view in centipawns.
@@ -316,7 +323,7 @@ string UCI::value(Value v) {
   stringstream ss;
 
   if (abs(v) < VALUE_TB_WIN_IN_MAX_PLY)
-      ss << "cp " << v * 100 / NormalizeToPawnValue;
+      ss << "cp " << UCI::to_cp(v);
   else if (abs(v) < VALUE_MATE_IN_MAX_PLY)
   {
       const int ply = VALUE_MATE_IN_MAX_PLY - 1 - std::abs(v);  // recompute ss->ply