Merge with remote branch 'origin/main'

src/Lynx.Cli/appsettings.Development.json

@@ -1,4 +1,7 @@
 {
+ "GeneralSettings": {
+ "EnableTuning": true
+ },
  "EngineSettings": {
  "DefaultMaxDepth": 3,
  "TranspositionTableEnabled": true,

src/Lynx.Cli/appsettings.json

@@ -1,7 +1,8 @@
 {
  // Settings that affect the executable behavior
  "GeneralSettings": {
- "EnableLogging": true // logging can be completely disablesd, both console and file, setting this to false. Alternatively, one or more "NLog.rules" can be removed/tweaked
+ "EnableLogging": true, // logging can be completely disablesd, both console and file, setting this to false. Alternatively, one or more "NLog.rules" can be removed/tweaked
+ "EnableTuning": false // Exposes search tunable values via UCI. Intended to be used for developer only purposes
  },
 
  // Settings that affect the engine behavior

src/Lynx/Configuration.cs

@@ -72,6 +72,8 @@ public static int Hash
 public sealed class GeneralSettings
 {
  public bool EnableLogging { get; set; } = false;
+
+ public bool EnableTuning { get; set; } = false;
 }
 
 public sealed class EngineSettings

src/Lynx/SPSAAttribute.cs

@@ -1,4 +1,5 @@
-using System.Numerics;
+using NLog;
+using System.Numerics;
 using System.Reflection;
 using System.Text.Json;
 using System.Text.Json.Nodes;
@@ -47,7 +48,7 @@ public string ToOBString(PropertyInfo property)
  return $"{property.Name}, int, {val}, {MinValue}, {MaxValue}, {Step}, {Configuration.EngineSettings.SPSA_OB_R_end}";
  }
 
- private static T GetPropertyValue(PropertyInfo property)
+ internal static T GetPropertyValue(PropertyInfo property)
  {
  T val = (T)property.GetValue(Configuration.EngineSettings)!;
 
@@ -83,3 +84,148 @@ public string ToOBPrettyString(PropertyInfo property)
 #pragma warning restore IL2026 // Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code
  }
 }
+
+public static class SPSAAttributeHelpers
+{
+ private static readonly Logger _logger = LogManager.GetCurrentClassLogger();
+
+ public static IEnumerable<string> GenerateOpenBenchStrings()
+ {
+ foreach (var property in typeof(EngineSettings).GetProperties())
+ {
+ var genericType = typeof(SPSAAttribute<>);
+ var spsaArray = property.GetCustomAttributes(genericType);
+ var count = spsaArray.Count();
+
+ if (count > 1)
+ {
+ _logger.Warn("Property {0} has more than one [{1}]", property.Name, genericType.Name);
+ }
+
+ if (count == 0)
+ {
+ continue;
+ }
+
+ var genericSpsa = spsaArray.First();
+ if (genericSpsa is SPSAAttribute<int> intSpsa)
+ {
+ yield return intSpsa.ToOBString(property);
+ }
+ else if (genericSpsa is SPSAAttribute<double> doubleSpsa)
+ {
+ yield return doubleSpsa.ToOBString(property);
+ }
+ else
+ {
+ _logger.Error("Property {0} has a [{1}] defined with unsupported type <{2}>", property.Name, genericSpsa);
+ }
+ }
+ }
+
+ public static IEnumerable<string> GenerateOpenBenchPrettyStrings()
+ {
+ foreach (var property in typeof(EngineSettings).GetProperties())
+ {
+ var genericType = typeof(SPSAAttribute<>);
+ var spsaArray = property.GetCustomAttributes(genericType);
+ var count = spsaArray.Count();
+
+ if (count > 1)
+ {
+ _logger.Warn("Property {0} has more than one [{1}]", property.Name, genericType.Name);
+ }
+
+ if (count == 0)
+ {
+ continue;
+ }
+
+ var genericSpsa = spsaArray.First();
+ if (genericSpsa is SPSAAttribute<int> intSpsa)
+ {
+ yield return intSpsa.ToOBPrettyString(property);
+ }
+ else if (genericSpsa is SPSAAttribute<double> doubleSpsa)
+ {
+ yield return doubleSpsa.ToOBPrettyString(property);
+ }
+ else
+ {
+ _logger.Error("Property {0} has a [{1}] defined with unsupported type <{2}>", property.Name, genericSpsa);
+ }
+ }
+ }
+
+ public static IEnumerable<KeyValuePair<string, JsonNode?>> GenerateWeatherFactoryStrings()
+ {
+ foreach (var property in typeof(EngineSettings).GetProperties())
+ {
+ var genericType = typeof(SPSAAttribute<>);
+ var spsaArray = property.GetCustomAttributes(genericType);
+ var count = spsaArray.Count();
+
+ if (count > 1)
+ {
+ _logger.Warn("Property {0} has more than one [{1}]", property.Name, genericType.Name);
+ }
+
+ if (count == 0)
+ {
+ continue;
+ }
+
+ var genericSpsa = spsaArray.First();
+ if (genericSpsa is SPSAAttribute<int> intSpsa)
+ {
+ yield return intSpsa.ToWeatherFactoryString(property);
+ }
+ else if (genericSpsa is SPSAAttribute<double> doubleSpsa)
+ {
+ yield return doubleSpsa.ToWeatherFactoryString(property);
+ }
+ else
+ {
+ _logger.Error("Property {0} has a [{1}] defined with unsupported type <{2}>", property.Name, genericSpsa);
+ }
+ }
+ }
+
+ public static IEnumerable<string> GenerateOptionStrings()
+ {
+ foreach (var property in typeof(EngineSettings).GetProperties())
+ {
+ var genericType = typeof(SPSAAttribute<>);
+ var spsaArray = property.GetCustomAttributes(genericType);
+ var count = spsaArray.Count();
+
+ if (count > 1)
+ {
+ _logger.Warn("Property {0} has more than one [{1}]", property.Name, genericType.Name);
+ }
+
+ if (count == 0)
+ {
+ continue;
+ }
+
+ var genericSpsa = spsaArray.First();
+ if (genericSpsa is SPSAAttribute<int> intSpsa)
+ {
+ var val = SPSAAttribute<int>.GetPropertyValue(property);
+
+ yield return $"option name {property.Name} type spin default {val} min {intSpsa.MinValue} max {intSpsa.MaxValue}";
+ }
+ else if (genericSpsa is SPSAAttribute<double> doubleSpsa)
+ {
+ var val = SPSAAttribute<double>.GetPropertyValue(property);
+
+ yield return $"option name {property.Name} type spin default {val} min {doubleSpsa.MinValue} max {doubleSpsa.MaxValue}";
+ }
+ else
+ {
+ _logger.Error("Property {0} has a [{1}] defined with unsupported type <{2}>", property.Name, genericSpsa);
+ }
+ }
+ }
+}

src/Lynx/Search/NegaMax.cs

@@ -97,30 +97,6 @@ private int NegaMax(int depth, int ply, int alpha, int beta, bool parentWasNullM
  staticEval = ttScore;
  }
 
- // 🔍 Null Move Pruning (NMP) - our position is so good that we can potentially afford giving our opponent a double move and still remain ahead of beta
- if (depth >= Configuration.EngineSettings.NMP_MinDepth
- && staticEval >= beta
- && !parentWasNullMove
- && phase > 2 // Zugzwang risk reduction: pieces other than pawn presents
- && (ttElementType != NodeType.Alpha || ttEvaluation >= beta)) // TT suggests NMP will fail: entry must not be a fail-low entry with a score below beta - Stormphrax and Ethereal
- {
- var nmpReduction = Configuration.EngineSettings.NMP_BaseDepthReduction + ((depth + Configuration.EngineSettings.NMP_DepthIncrement) / Configuration.EngineSettings.NMP_DepthDivisor); // Clarity
-
- // TODO more advanced adaptative reduction, similar to what Ethereal and Stormphrax are doing
- //var nmpReduction = Math.Min(
- // depth,
- // 3 + (depth / 3) + Math.Min((staticEval - beta) / 200, 3));
-
- var gameState = position.MakeNullMove();
- var evaluation = -NegaMax(depth - 1 - nmpReduction, ply + 1, -beta, -beta + 1, parentWasNullMove: true);
- position.UnMakeNullMove(gameState);
-
- if (evaluation >= beta)
- {
- return evaluation;
- }
- }
-
  if (depth <= Configuration.EngineSettings.RFP_MaxDepth)
  {
  // 🔍 Reverse Futility Pruning (RFP) - https://www.chessprogramming.org/Reverse_Futility_Pruning
@@ -163,6 +139,30 @@ private int NegaMax(int depth, int ply, int alpha, int beta, bool parentWasNullM
  }
  }
  }
+
+ // 🔍 Null Move Pruning (NMP) - our position is so good that we can potentially afford giving our opponent a double move and still remain ahead of beta
+ if (depth >= Configuration.EngineSettings.NMP_MinDepth
+ && staticEval >= beta
+ && !parentWasNullMove
+ && phase > 2 // Zugzwang risk reduction: pieces other than pawn presents
+ && (ttElementType != NodeType.Alpha || ttEvaluation >= beta)) // TT suggests NMP will fail: entry must not be a fail-low entry with a score below beta - Stormphrax and Ethereal
+ {
+ var nmpReduction = Configuration.EngineSettings.NMP_BaseDepthReduction + ((depth + Configuration.EngineSettings.NMP_DepthIncrement) / Configuration.EngineSettings.NMP_DepthDivisor); // Clarity
+
+ // TODO more advanced adaptative reduction, similar to what Ethereal and Stormphrax are doing
+ //var nmpReduction = Math.Min(
+ // depth,
+ // 3 + (depth / 3) + Math.Min((staticEval - beta) / 200, 3));
+
+ var gameState = position.MakeNullMove();
+ var evaluation = -NegaMax(depth - 1 - nmpReduction, ply + 1, -beta, -beta + 1, parentWasNullMove: true);
+ position.UnMakeNullMove(gameState);
+
+ if (evaluation >= beta)
+ {
+ return evaluation;
+ }
+ }
  }
 
  Span<Move> moves = stackalloc Move[Constants.MaxNumberOfPossibleMovesInAPosition];

src/Lynx/UCI/Commands/Engine/OptionCommand.cs

@@ -124,42 +124,15 @@ public sealed class OptionCommand : EngineBaseCommand
  public const string Id = "option";
 
  public static readonly ImmutableArray<string> AvailableOptions =
- [
- "option name UCI_Opponent type string",
- $"option name UCI_EngineAbout type string default {IdCommand.EngineName} by {IdCommand.EngineAuthor}, see https:/lynx-chess/Lynx",
- $"option name UCI_ShowWDL type check default {Configuration.EngineSettings.ShowWDL}",
- $"option name Hash type spin default {Configuration.EngineSettings.TranspositionTableSize} min {Constants.AbsoluteMinTTSize} max {Constants.AbsoluteMaxTTSize}",
- $"option name OnlineTablebaseInRootPositions type check default {Configuration.EngineSettings.UseOnlineTablebaseInRootPositions}",
- "option name Threads type spin default 1 min 1 max 1",
-
- #region Search tuning
-
- $"option name {nameof(Configuration.EngineSettings.LMR_MinDepth)} type spin default {Configuration.EngineSettings.LMR_MinDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMR_MinFullDepthSearchedMoves)} type spin default {Configuration.EngineSettings.LMR_MinFullDepthSearchedMoves} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMR_Base)} type spin default {100 * Configuration.EngineSettings.LMR_Base} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMR_Divisor)} type spin default {100 * Configuration.EngineSettings.LMR_Divisor} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.NMP_MinDepth)} type spin default {Configuration.EngineSettings.NMP_MinDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.NMP_BaseDepthReduction)} type spin default {Configuration.EngineSettings.NMP_BaseDepthReduction} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.NMP_DepthIncrement)} type spin default {Configuration.EngineSettings.NMP_DepthIncrement} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.NMP_DepthDivisor)} type spin default {Configuration.EngineSettings.NMP_DepthDivisor} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.AspirationWindow_Delta)} type spin default {Configuration.EngineSettings.AspirationWindow_Delta} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.AspirationWindow_MinDepth)} type spin default {Configuration.EngineSettings.AspirationWindow_MinDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.RFP_MaxDepth)} type spin default {Configuration.EngineSettings.RFP_MaxDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.RFP_DepthScalingFactor)} type spin default {Configuration.EngineSettings.RFP_DepthScalingFactor} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.Razoring_MaxDepth)} type spin default {Configuration.EngineSettings.Razoring_MaxDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.Razoring_Depth1Bonus)} type spin default {Configuration.EngineSettings.Razoring_Depth1Bonus} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.Razoring_NotDepth1Bonus)} type spin default {Configuration.EngineSettings.Razoring_NotDepth1Bonus} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.IIR_MinDepth)} type spin default {Configuration.EngineSettings.IIR_MinDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMP_MaxDepth)} type spin default {Configuration.EngineSettings.LMP_MaxDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMP_BaseMovesToTry)} type spin default {Configuration.EngineSettings.LMP_BaseMovesToTry} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.LMP_MovesDepthMultiplier)} type spin default {Configuration.EngineSettings.LMP_MovesDepthMultiplier} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.SEE_BadCaptureReduction)} type spin default {Configuration.EngineSettings.SEE_BadCaptureReduction} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.FP_MaxDepth)} type spin default {Configuration.EngineSettings.FP_MaxDepth} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.FP_DepthScalingFactor)} type spin default {Configuration.EngineSettings.FP_DepthScalingFactor} min 0 max 1024",
- $"option name {nameof(Configuration.EngineSettings.FP_Margin)} type spin default {Configuration.EngineSettings.FP_Margin} min 0 max 1024",
-
- #endregion
- ];
+ [
+ "option name UCI_Opponent type string",
+ $"option name UCI_EngineAbout type string default {IdCommand.EngineName} by {IdCommand.EngineAuthor}, see https:/lynx-chess/Lynx",
+ $"option name UCI_ShowWDL type check default {Configuration.EngineSettings.ShowWDL}",
+ $"option name Hash type spin default {Configuration.EngineSettings.TranspositionTableSize} min {Constants.AbsoluteMinTTSize} max {Constants.AbsoluteMaxTTSize}",
+ $"option name OnlineTablebaseInRootPositions type check default {Configuration.EngineSettings.UseOnlineTablebaseInRootPositions}",
+ "option name Threads type spin default 1 min 1 max 1",
+ .. Configuration.GeneralSettings.EnableTuning ? SPSAAttributeHelpers.GenerateOptionStrings() : []
+ ];
 
  //"option name UCI_AnalyseMode type check",
  //"option name NalimovPath type string default C:/...",