private void ReportStatus(MonteCarloTreeSearchNode rootNode)
{
// Update Status
if (statusUpdate.ElapsedMilliseconds > millisecondsBetweenUpdates && OnStatus != null)
{
EngineStatus status = new EngineStatus();
foreach (var child in rootNode.Children)
{
double eval = Math.Round((child.Visits > 0 ? 200.0 * child.Wins / child.Visits : 0) - 100.0, 2);
string pv = "";
var c = child;
while (c != null && c.Move >= 0 && c.Move <= 80)
{
pv += /*(c.LastToMove == Player.One ? "b " : "o ") +*/ Constants.TileNames[c.Move] + " (" + c.Wins + "/" + c.Visits + ") ";
c = c.Children?.OrderBy(x => x.Visits)?.ThenBy(x => x.Wins)?.LastOrDefault();
}
status.Add(child?.Move ?? 80, eval, pv, child.Visits);
}
status.Sort();
OnStatus?.Invoke(this, status);
statusUpdate = Stopwatch.StartNew();
}
}
private int MonteCarloTreeSearch(Board rootState)
{
var rootNode = new MonteCarloTreeSearchNode(rootState, GetMoves);
var forceEnd = false;
var parallelism = 8;
var semaphore = new Semaphore(parallelism, parallelism);
for (int i = 0; i < maxIterations && !cancel.Cancelled && !forceEnd; i++)
{
var node = rootNode;
var state = new Board(rootState);
simulationCount++;
// Select
while (node.Untried.Count == 0 && node.Children.Count > 0)
{
node = node.SelectChild();
state.MakeMove(node.Move);
visitedNodes++;
}
// Expand
if (node.Untried.Count > 0)
{
var move = node.Untried[random.Next(node.Untried.Count)];
state.MakeMove(move);
node = node.AddChild(state, move);
visitedNodes++;
}
semaphore.WaitOne();
Task.Run(() =>
{
// Simulate
while (state.Winner == Player.Empty && state.Turn < VolcanoGame.Settings.TournamentAdjudicateMaxTurns)
{
var moves = GetRandomMoves(state);
if (moves.Count == 0)
{
break;
}
state.MakeMove(moves[random.Next(moves.Count)]);
visitedNodes++;
}
// Backpropagate
while (node != null)
{
if (forceEnd)
{
break;
}
//var fastWinReward = 0.5 * (state.Turn - rootState.Turn) / VolcanoGame.Settings.TournamentAdjudicateMaxTurns;
//node.Update(state.Winner == node.LastToMove ? 1.0 - fastWinReward : 0.0);
node.Update(state.Winner == node.LastToMove ? 1.0 : 0.0);
node = node.Parent;
visitedNodes++;
}
semaphore.Release();
});
// Cut Short
foreach (var child in rootNode.Children)
{
// If we have a potential move that has a 100% win rate and it's been visited a lot of times, stop searching
if (child.Visits > 500 && child.Wins == child.Visits)
{
forceEnd = true;
}
}
// Update Status
if (statusUpdate.ElapsedMilliseconds > millisecondsBetweenUpdates && OnStatus != null)
{
EngineStatus status = new EngineStatus();
foreach (var child in rootNode.Children)
{
double eval = Math.Round((child.Visits > 0 ? 200.0 * Math.Min(child.Wins, child.Visits) / child.Visits : 0) - 100.0, 2);
string pv = "";
var c = child;
while (c != null && c.Move >= 0 && c.Move <= 80)
{
pv += Constants.TileNames[c.Move] + " (" + Math.Round(c.Wins, 2) + "/" + c.Visits + ") ";
c = c.Children?.OrderBy(x => x.Visits)?.ThenBy(x => x.Wins)?.LastOrDefault();
}
status.Add(child?.Move ?? 80, eval, pv, child.Visits);
}
status.Sort();
OnStatus(this, status);
statusUpdate = Stopwatch.StartNew();
}
}
forceEnd = true;
return(rootNode.Children.OrderBy(x => x.Visits).LastOrDefault().Move);
}
private int MonteCarloTreeSearch(Board rootState)
{
var rootNode = new MonteCarloTreeSearchNode(rootState, GetMoves);
var forceWin = false;
while (!cancel.Cancelled && !forceWin)
{
var node = rootNode;
var state = new Board(rootState);
state.allowHash = _allowHash;
state.fastWinSearch = _allowFastWinSearch;
if (_allowHash)
{
state.winHashes = winHashes;
}
simulationCount++;
// Select
while (node.Untried.Count == 0 && node.Children.Count > 0)
{
node = node.SelectChild(_ucbFactor);
state.MakeMove(node.Move);
visitedNodes++;
}
// Expand
if (node.Untried.Count > 0)
{
var move = node.Untried[random.Next(node.Untried.Count)];
state.MakeMove(move);
node = node.AddChild(state, move);
visitedNodes++;
}
// Simulate
while (state.Winner == Player.Empty && state.Turn < VolcanoGame.Settings.TournamentAdjudicateMaxTurns)
{
var moves = state.GetMoves();
if (moves.Count == 0)
{
break;
}
state.MakeMove(moves[random.Next(moves.Count)]);
visitedNodes++;
}
// Backpropagate
while (node != null)
{
node.Update(state.Winner == node.LastToMove ? 1.0 : 0.0);
node = node.Parent;
visitedNodes++;
}
// Cut Short
if (_allowForcedWins)
{
foreach (var child in rootNode.Children)
{
// If we have a potential move that has a 100% win rate and it's been visited a lot of times, stop searching
if (child.Visits > 500 && child.Wins == child.Visits)
{
forceWin = true;
}
}
}
// Update Status
if (statusUpdate.ElapsedMilliseconds > millisecondsBetweenUpdates && OnStatus != null)
{
EngineStatus status = new EngineStatus();
foreach (var child in rootNode.Children)
{
double eval = Math.Round((child.Visits > 0 ? 200.0 * child.Wins / child.Visits : 0) - 100.0, 2);
string pv = "";
var c = child;
while (c != null && c.Move >= 0 && c.Move <= 80)
{
pv += Constants.TileNames[c.Move] + " (" + c.Wins + "/" + c.Visits + ") ";
c = c.Children?.OrderBy(x => x.Visits)?.ThenBy(x => x.Wins)?.LastOrDefault();
}
status.Add(child?.Move ?? 80, eval, pv, child.Visits);
}
status.Sort();
OnStatus?.Invoke(this, status);
statusUpdate = Stopwatch.StartNew();
}
}
return(rootNode.Children.OrderBy(x => x.Visits).LastOrDefault().Move);
}