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Update Stockfish to development version from 2020-06-17

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Peter Osterlund
2020-06-19 11:49:56 +02:00
parent a64eab03cc
commit 6bcbd6d080
34 changed files with 1445 additions and 885 deletions
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116
DroidFishApp/src/main/cpp/stockfish/timeman.cpp
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@@ -28,66 +28,21 @@
TimeManagement Time; // Our global time management object
namespace {
enum TimeType { OptimumTime, MaxTime };
constexpr int MoveHorizon = 50; // Plan time management at most this many moves ahead
constexpr double MaxRatio = 7.3; // When in trouble, we can step over reserved time with this ratio
constexpr double StealRatio = 0.34; // However we must not steal time from remaining moves over this ratio
// move_importance() is a skew-logistic function based on naive statistical
// analysis of "how many games are still undecided after n half-moves". Game
// is considered "undecided" as long as neither side has >275cp advantage.
// Data was extracted from the CCRL game database with some simple filtering criteria.
double move_importance(int ply) {
constexpr double XScale = 6.85;
constexpr double XShift = 64.5;
constexpr double Skew = 0.171;
return pow((1 + exp((ply - XShift) / XScale)), -Skew) + DBL_MIN; // Ensure non-zero
}
template<TimeType T>
TimePoint remaining(TimePoint myTime, int movesToGo, int ply, TimePoint slowMover) {
constexpr double TMaxRatio = (T == OptimumTime ? 1.0 : MaxRatio);
constexpr double TStealRatio = (T == OptimumTime ? 0.0 : StealRatio);
double moveImportance = (move_importance(ply) * slowMover) / 100.0;
double otherMovesImportance = 0.0;
for (int i = 1; i < movesToGo; ++i)
otherMovesImportance += move_importance(ply + 2 * i);
double ratio1 = (TMaxRatio * moveImportance) / (TMaxRatio * moveImportance + otherMovesImportance);
double ratio2 = (moveImportance + TStealRatio * otherMovesImportance) / (moveImportance + otherMovesImportance);
return TimePoint(myTime * std::min(ratio1, ratio2)); // Intel C++ asks for an explicit cast
}
} // namespace
/// init() is called at the beginning of the search and calculates the allowed
/// thinking time out of the time control and current game ply. We support four
/// different kinds of time controls, passed in 'limits':
///
/// inc == 0 && movestogo == 0 means: x basetime [sudden death!]
/// inc == 0 && movestogo != 0 means: x moves in y minutes
/// inc > 0 && movestogo == 0 means: x basetime + z increment
/// inc > 0 && movestogo != 0 means: x moves in y minutes + z increment
/// init() is called at the beginning of the search and calculates the bounds
/// of time allowed for the current game ply. We currently support:
// 1) x basetime (+z increment)
// 2) x moves in y seconds (+z increment)
void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
TimePoint minThinkingTime = Options["Minimum Thinking Time"];
TimePoint moveOverhead = Options["Move Overhead"];
TimePoint slowMover = Options["Slow Mover"];
TimePoint npmsec = Options["nodestime"];
TimePoint hypMyTime;
TimePoint minThinkingTime = TimePoint(Options["Minimum Thinking Time"]);
TimePoint moveOverhead = TimePoint(Options["Move Overhead"]);
TimePoint slowMover = TimePoint(Options["Slow Mover"]);
TimePoint npmsec = TimePoint(Options["nodestime"]);
// opt_scale is a percentage of available time to use for the current move.
// max_scale is a multiplier applied to optimumTime.
double opt_scale, max_scale;
// If we have to play in 'nodes as time' mode, then convert from time
// to nodes, and use resulting values in time management formulas.
@@ -105,29 +60,40 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
}
startTime = limits.startTime;
optimumTime = maximumTime = std::max(limits.time[us], minThinkingTime);
const int maxMTG = limits.movestogo ? std::min(limits.movestogo, MoveHorizon) : MoveHorizon;
//Maximum move horizon of 50 moves
int mtg = limits.movestogo ? std::min(limits.movestogo, 50) : 50;
// 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.
for (int hypMTG = 1; hypMTG <= maxMTG; ++hypMTG)
// Make sure timeLeft is > 0 since we may use it as a divisor
TimePoint timeLeft = std::max(TimePoint(1),
limits.time[us] + limits.inc[us] * (mtg - 1) - moveOverhead * (2 + mtg));
// A user may scale time usage by setting UCI option "Slow Mover"
// Default is 100 and changing this value will probably lose elo.
timeLeft = slowMover * timeLeft / 100;
// x basetime (+ z increment)
// If there is a healthy increment, timeLeft can exceed actual available
// game time for the current move, so also cap to 20% of available game time.
if (limits.movestogo == 0)
{
// Calculate thinking time for hypothetical "moves to go"-value
hypMyTime = limits.time[us]
+ limits.inc[us] * (hypMTG - 1)
- moveOverhead * (2 + std::min(hypMTG, 40));
hypMyTime = std::max(hypMyTime, TimePoint(0));
TimePoint t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, ply, slowMover);
TimePoint t2 = minThinkingTime + remaining<MaxTime >(hypMyTime, hypMTG, ply, slowMover);
optimumTime = std::min(t1, optimumTime);
maximumTime = std::min(t2, maximumTime);
opt_scale = std::min(0.008 + std::pow(ply + 3.0, 0.5) / 250.0,
0.2 * limits.time[us] / double(timeLeft));
max_scale = 4 + std::min(36, ply) / 12.0;
}
// x moves in y seconds (+ z increment)
else
{
opt_scale = std::min((0.8 + ply / 128.0) / mtg,
0.8 * limits.time[us] / double(timeLeft));
max_scale = std::min(6.3, 1.5 + 0.11 * mtg);
}
// Never use more than 80% of the available time for this move
optimumTime = std::max(minThinkingTime, TimePoint(opt_scale * timeLeft));
maximumTime = TimePoint(std::min(0.8 * limits.time[us] - moveOverhead, max_scale * optimumTime));
if (Options["Ponder"])
optimumTime += optimumTime / 4;
}