private void FloodFillMinDistancesQueen(Point point, PieceGrid pieceGrid, PointSquareArray <double?> result)
{
ISet <Point> visited = new HashSet <Point>();
Queue <(Point, double)> toVisit = new Queue <(Point, double)>();
foreach (Point p in pieceGrid.GetOpenPointsOutFrom(point))
{
toVisit.Enqueue((p, 1));
}
while (toVisit.Any())
{
(Point, double)p = toVisit.Dequeue();
if (visited.Contains(p.Item1))
{
continue;
}
if (result[p.Item1].HasValue)
{
result[p.Item1] = Math.Min(p.Item2, result[p.Item1].Value);
}
else
{
result.Add(p.Item1, p.Item2);
}
visited.Add(p.Item1);
foreach (Point pNext in pieceGrid.GetOpenPointsOutFrom(p.Item1)
.Where(adj => !visited.Contains(adj)))
{
toVisit.Enqueue((pNext, p.Item2 + 1));
}
}
}
public void ApplyReverseMove(Move move)
{
Owner owner = PreviousPlayer;
if (PieceGrid.PointPieces[move.AmazonsPoint].Owner != owner)
{
throw new ArgumentException($"Reverse move given doesn't correspond to {owner} previous turn. Move: {move}");
}
if (PieceGrid.PointPieces[move.AmazonsPoint].Name != PieceName.Amazon)
{
throw new ArgumentException($"Reverse move given isn't on an Amazon. You cannot move a {PieceGrid.PointPieces[move.Origin].Name}. Move: {move}");
}
PieceGrid.ApplyReverseMove(move);
if (owner == Owner.Player1)
{
Player1MoveCount--;
}
else
{
Player2MoveCount--;
}
_moves.Clear();
}
/// <summary>
/// Create a dictionary of points mapped to the minimum distance to that point for the given player and move type.
/// As a side effect, this fills the Specific*Distances dictionary for the given <paramref name="owner"/>
/// </summary>
/// <param name="pieceGrid">PieceGrid to analyze</param>
/// <param name="owner">Player whos amazons we are calculating distance for</param>
/// <param name="queen">True for Queen distances, false for King distances</param>
/// <returns>Dictionary of Points with their minimum distance values for the given player and move type</returns>
private PointSquareArray <double?> BuildDistancesDictionary(PieceGrid pieceGrid, Owner owner, bool queen)
{
var distancesDictionary = new PointSquareArray <double?>(pieceGrid.Size);
ISet <Point> amazonPoints;
if (owner == Owner.Player1)
{
amazonPoints = pieceGrid.Amazon1Points;
}
else
{
amazonPoints = pieceGrid.Amazon2Points;
}
foreach (Point amazonPoint in amazonPoints)
{
if (queen)
{
FloodFillMinDistancesQueen(amazonPoint, pieceGrid, distancesDictionary);
}
else
{
FloodFillMinDistancesKing(amazonPoint, pieceGrid, distancesDictionary);
}
}
return(distancesDictionary);
}
public Board Clone()
{
Board newBoard = new Board();
newBoard.PieceGrid = PieceGrid.Clone();
newBoard.Player1MoveCount = Player1MoveCount;
newBoard.Player2MoveCount = Player2MoveCount;
return(newBoard);
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
PieceGrid pieceGrid = (PieceGrid)value;
writer.WriteStartObject();
writer.WritePropertyName("Size");
writer.WriteValue(pieceGrid.Size);
writer.WritePropertyName("PointPieces");
serializer.Serialize(writer, pieceGrid.PointPieces);
writer.WriteEndObject();
}
/// <summary>
/// Calculate the mobility score for all amazons on the PieceGrid
/// </summary>
/// <param name="pieceGrid">PieceGrid to analyze</param>
private void CalculateAllAmazonMobility(PieceGrid pieceGrid)
{
AmazonMobilityScores.Clear();
foreach (Point p in pieceGrid.Amazon1Points)
{
AmazonMobilityScores.Add(p, CalculateAmazonMobility(p, Owner.Player1, pieceGrid));
}
foreach (Point p in pieceGrid.Amazon2Points)
{
AmazonMobilityScores.Add(p, CalculateAmazonMobility(p, Owner.Player2, pieceGrid));
}
}
/// <summary>
/// Build all the internal analysis data for the given PieceGrid
/// </summary>
/// <param name="pieceGrid">PieceGrid to analyze</param>
/// <param name="playerToMove">Player whos turn it is</param>
public void BuildAnalysis(PieceGrid pieceGrid, Owner playerToMove)
{
if (pieceGrid.Id == LastAnalyzedPieceGridId)
{
return;
}
LastAnalyzedPieceGridId = pieceGrid.Id;
LocalAdvantages = new PointSquareArray <LocalAdvantage>(pieceGrid.Size);
Player1QueenMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player1);
Player2QueenMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player2);
CalculateLocalAdvantages(pieceGrid, playerToMove);
T1 = LocalAdvantages.Where(a => a.Value != null).Sum(a => a.Value.DeltaQueen);
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
Newtonsoft.Json.Linq.JObject o = Newtonsoft.Json.Linq.JObject.Load(reader);
int size = o.Value <int>("Size");
PieceGrid newPieceGrid = new PieceGrid(size);
var pieceGridJson = o.Value <JObject>("PointPieces");
Dictionary <Point, Piece> pointPiecesDictionary = new Dictionary <Point, Piece>();
foreach (KeyValuePair <string, JToken> kvp in pieceGridJson)
{
Point point = Point.Get(kvp.Key);
Piece piece = Piece.Get(kvp.Value.Value <string>());
pointPiecesDictionary.Add(point, piece);
}
newPieceGrid.Initialize(pointPiecesDictionary);
return(newPieceGrid);
}
/// <summary>
/// Build <see cref="LocalAdvantage"/> objects for each open space on the PieceGrid
/// </summary>
/// <param name="pieceGrid">PieceGrid to analyze</param>
/// <param name="playerToMove">Player whos turn it is</param>
private void CalculateLocalAdvantages(PieceGrid pieceGrid, Owner playerToMove)
{
LocalAdvantages.Clear();
foreach (var kvp in pieceGrid.PointPieces)
{
if (!(kvp.Value is Open))
{
continue;
}
double player1QueenDistance = Player1QueenMinDistances[kvp.Key] ?? 1000d;
double player2QueenDistance = Player2QueenMinDistances[kvp.Key] ?? 1000d;
LocalAdvantage advantageValue = new LocalAdvantage
{
Player1QueenDistance = player1QueenDistance,
Player2QueenDistance = player2QueenDistance,
PlayerToMove = playerToMove,
};
LocalAdvantages[kvp.Key] = advantageValue;
}
}
private void FloodFillMinDistancesKing(Point point, PieceGrid pieceGrid, PointSquareArray <double?> result)
{
ISet <Point> visited = new HashSet <Point>();
Queue <(Point, double)> toVisit = new Queue <(Point, double)>();
foreach (Point p in point.GetAdjacentPoints().Where(adj => !pieceGrid.IsOutOfBounds(adj) &&
!pieceGrid.PointPieces[adj].Impassible))
{
toVisit.Enqueue((p, 1));
}
while (toVisit.Any())
{
(Point, double)p = toVisit.Dequeue();
if (visited.Contains(p.Item1))
{
continue;
}
if (result[p.Item1].HasValue)
{
result[p.Item1] = Math.Min(p.Item2, result[p.Item1].Value);
}
else
{
result.Add(p.Item1, p.Item2);
}
if (SpecificKingDistances[point] == null)
{
SpecificKingDistances.Add(point, new PointSquareArray <double>(pieceGrid.Size));
}
SpecificKingDistances[point].Add(p.Item1, p.Item2);
visited.Add(p.Item1);
foreach (Point pNext in p.Item1.GetAdjacentPoints()
.Where(adj => !pieceGrid.IsOutOfBounds(adj) &&
!pieceGrid.PointPieces[adj].Impassible &&
!visited.Contains(adj)))
{
toVisit.Enqueue((pNext, p.Item2 + 1));
}
}
}
/// <summary>
/// Calculate the mobility score for a specific amazon point on the PieceGrid.
/// </summary>
/// <remarks>
/// Mobility is based on the breathing space of each space that can be moved to by an
/// amazon at the given point. Closer (king distance) spaces are more valuable than
/// distant ones.
/// </remarks>
/// <param name="p">Point containing an amazon</param>
/// <param name="pieceGrid">PieceGrid to analyze</param>
/// <returns>Numeric mobility score, higher numbers = more mobile</returns>
private double CalculateAmazonMobility(Point p, Owner owner, PieceGrid pieceGrid)
{
IDictionary <Point, double?> minDistancesOppositePlayer;
if (owner == Owner.Player1)
{
minDistancesOppositePlayer = Player2QueenMinDistances;
}
else if (owner == Owner.Player2)
{
minDistancesOppositePlayer = Player1QueenMinDistances;
}
else
{
throw new ArgumentException($"Point {p} doesn't have an amazon for either player!");
}
double mobility = 0d;
foreach (Point target in pieceGrid.GetOpenPointsOutFrom(p))
{
int degree = target.GetAdjacentPoints()
.Where(adj => pieceGrid.PointPieces.ContainsKey(adj) && !pieceGrid.PointPieces[adj].Impassible)
.Count();
if (!minDistancesOppositePlayer.ContainsKey(target))
{
continue;
}
if (owner == Owner.Player1 && !LocalAdvantages[target].Player2Reachable)
{
continue;
}
if (owner == Owner.Player2 && !LocalAdvantages[target].Player1Reachable)
{
continue;
}
double localMobility = Math.Pow(2, -(SpecificKingDistances[p][target])) * degree;
mobility += localMobility;
}
return(mobility);
}
/// <summary>
/// Build all the internal analysis data for the given PieceGrid
/// </summary>
/// <param name="pieceGrid">PieceGrid to analyze</param>
/// <param name="playerToMove">Player whos turn it is</param>
public void BuildAnalysis(PieceGrid pieceGrid, Owner playerToMove)
{
if (pieceGrid.Id == LastAnalyzedPieceGridId)
{
return;
}
LastAnalyzedPieceGridId = pieceGrid.Id;
LocalAdvantages = new PointSquareArray <LocalAdvantage>(pieceGrid.Size);
AmazonMobilityScores = new PointSquareArray <double>(pieceGrid.Size);
SpecificQueenDistances = new PointSquareArray <PointSquareArray <double> >(pieceGrid.Size);
SpecificKingDistances = new PointSquareArray <PointSquareArray <double> >(pieceGrid.Size);
SpecificQueenDistances.Clear();
SpecificKingDistances.Clear();
Player1QueenMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player1, true);
Player1KingMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player1, false);
Player2QueenMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player2, true);
Player2KingMinDistances = BuildDistancesDictionary(pieceGrid, Owner.Player2, false);
CalculateLocalAdvantages(pieceGrid, playerToMove);
CalculateAllAmazonMobility(pieceGrid);
W = LocalAdvantages.Where(a => a.Value != null && a.Value.Player1Reachable && a.Value.Player2Reachable)
.Sum(a => Math.Pow(2, -(Math.Abs(a.Value.Player1QueenDistance - a.Value.Player2QueenDistance))));
C1 = 2 * LocalAdvantages.Where(a => a.Value != null).Sum(a => Math.Pow(2, -(a.Value.Player1QueenDistance)) - Math.Pow(2, -(a.Value.Player2QueenDistance)));
C2 = LocalAdvantages.Where(a => a.Value != null).Sum(a => Math.Min(1, Math.Max(-1, (a.Value.Player2KingDistance - a.Value.Player1KingDistance) / 6d)));
T1 = LocalAdvantages.Where(a => a.Value != null).Sum(a => a.Value.DeltaQueen);
T2 = LocalAdvantages.Where(a => a.Value != null).Sum(a => a.Value.DeltaKing);
T = (F1(W) * T1) + (F2(W) * C1) + (F3(W) * C2) + (F4(W) * T2);
double player1MobilitySum = AmazonMobilityScores.Where(s => pieceGrid.Amazon1Points.Contains(s.Key))
.Sum(s => IndividualWeightForM(W, s.Value));
double player2MobilitySum = AmazonMobilityScores.Where(s => pieceGrid.Amazon2Points.Contains(s.Key))
.Sum(s => IndividualWeightForM(W, s.Value));
M = player2MobilitySum - player1MobilitySum;
}
public IEnumerable <Move> GetAvailableMoves(Owner owner = Owner.None, bool reverse = false)
{
bool cached = false;
if (owner == Owner.None)
{
cached = _moves.ContainsKey(Owner.Player1) && _moves.ContainsKey(Owner.Player2);
}
else
{
cached = _moves.ContainsKey(owner);
}
if (!cached)
{
IEnumerable <Point> sourceSet;
if (owner == Owner.Player1)
{
List <Move> results = new List <Move>();
foreach (Point p in PieceGrid.Amazon1Points)
{
if (reverse)
{
results.AddRange(PieceGrid.GetReverseMovesFromPoint(p, owner));
}
else
{
results.AddRange(PieceGrid.GetMovesFromPoint(p));
}
}
_moves[owner] = results;
}
else if (owner == Owner.Player2)
{
List <Move> results = new List <Move>();
foreach (Point p in PieceGrid.Amazon2Points)
{
if (reverse)
{
results.AddRange(PieceGrid.GetReverseMovesFromPoint(p, owner));
}
else
{
results.AddRange(PieceGrid.GetMovesFromPoint(p));
}
}
_moves[owner] = results;
}
else
{
List <Move> results1 = new List <Move>();
List <Move> results2 = new List <Move>();
sourceSet = PieceGrid.Amazon1Points.Union(PieceGrid.Amazon2Points);
foreach (Point p in PieceGrid.Amazon1Points)
{
if (reverse)
{
results1.AddRange(PieceGrid.GetReverseMovesFromPoint(p, Owner.Player1));
}
else
{
results1.AddRange(PieceGrid.GetMovesFromPoint(p));
}
}
_moves[Owner.Player1] = results1;
foreach (Point p in PieceGrid.Amazon2Points)
{
if (reverse)
{
results2.AddRange(PieceGrid.GetReverseMovesFromPoint(p, Owner.Player2));
}
else
{
results2.AddRange(PieceGrid.GetMovesFromPoint(p));
}
}
_moves[Owner.Player2] = results2;
}
}
if (owner == Owner.None)
{
return(_moves[Owner.Player1].Union(_moves[Owner.Player2]));
}
else
{
return(_moves[owner]);
}
}
public Board(PieceGrid grid)
{
PieceGrid = grid;
Player1MoveCount = grid.PointPieces.Count(kvp => kvp.Value is ArrowPlayer1);
Player2MoveCount = grid.PointPieces.Count(kvp => kvp.Value is ArrowPlayer2);
}
public Board(int size)
{
PieceGrid = new PieceGrid(size, PieceHelpers.GetInitialAmazonPositions(size));
}