private void Visit(CellState startCellState)
{
startCellState.Visited = true;
count++;
startCellState.DfsDepth = count;
startCellState.DfsLow = count;
foreach (CellState adjacentCellState in startCellState.GetAdjacentCellStates())
{
if (adjacentCellState.OccupationStatus != OccupationStatus.YourWall && adjacentCellState.OccupationStatus != OccupationStatus.OpponentWall)
{
if (!adjacentCellState.Visited)
{
Edge newEdge = new Edge
{
StartVertex = startCellState,
EndVertex = adjacentCellState
};
edgeStack.Push(newEdge);
adjacentCellState.ParentCellState = startCellState;
Visit(adjacentCellState);
if (adjacentCellState.DfsLow >= startCellState.DfsDepth)
{
// Create a biconnected component
BiconnectedComponent component = new BiconnectedComponent(nextComponentNumber);
nextComponentNumber++;
startCellState.GameState.AddBiconnectedComponent(component);
Edge poppedEdge = null;
do
{
poppedEdge = edgeStack.Pop();
component.AddCell(poppedEdge.StartVertex);
component.AddCell(poppedEdge.EndVertex);
poppedEdge.StartVertex.AddBiconnectedComponent(component);
poppedEdge.EndVertex.AddBiconnectedComponent(component);
}while (poppedEdge != newEdge);
}
if (adjacentCellState.DfsLow < startCellState.DfsLow)
{
startCellState.DfsLow = adjacentCellState.DfsLow;
}
}
else
if (!(adjacentCellState.ParentCellState == startCellState) && (adjacentCellState.DfsDepth < startCellState.DfsDepth))
{
// The link from startCellState to adjacentCellState is a back edge to an ancestor of startCellState:
Edge backEdge = new Edge
{
StartVertex = startCellState,
EndVertex = adjacentCellState
};
edgeStack.Push(backEdge);
if (adjacentCellState.DfsDepth < startCellState.DfsLow)
{
startCellState.DfsLow = adjacentCellState.DfsDepth;
}
}
}
}
}
private void CalculateOpponentsOverallMetrics(GameState gameState, MetricsEvaluator evaluator)
{
Metrics overallMetrics;
if (gameState.OpponentsCell.IsACutVertex)
{
gameState.OpponentsCell.CalculateSubtreeMetricsForOpponent(evaluator, null /* No entry component */);
overallMetrics = gameState.OpponentsCell.SubtreeMetricsForOpponent;
}
else
{
BiconnectedComponent playersComponent = gameState.OpponentsCell.GetBiconnectedComponents().FirstOrDefault();
if (playersComponent == null)
{
// The player has no more moves left - there are no edges leading from the cell, and hence no components to be part of!
overallMetrics = Metrics.Zero;
}
else
{
playersComponent.CalculateSubtreeMetricsForOpponent(evaluator, gameState.OpponentsCell);
overallMetrics = playersComponent.SubtreeMetricsForOpponent;
}
}
gameState.NumberOfCellsClosestToOpponent = overallMetrics.NumberOfCellsClosestToPlayer;
gameState.NumberOfCellsReachableByOpponent = overallMetrics.NumberOfCellsReachableByPlayer;
gameState.TotalDegreesOfCellsClosestToOpponent = overallMetrics.TotalDegreesOfCellsClosestToPlayer;
gameState.TotalDegreesOfCellsReachableByOpponent = overallMetrics.TotalDegreesOfCellsReachableByPlayer;
gameState.SumOfDistancesFromYouOnOpponentsClosestCells = overallMetrics.SumOfDistancesFromOtherPlayerOnClosestCells;
gameState.SumOfDistancesFromOpponentOnOpponentsClosestCells = overallMetrics.SumOfDistancesFromThisPlayerOnClosestCells;
gameState.NumberOfComponentBranchesInOpponentsTree = overallMetrics.NumberOfComponentBranchesInTree;
}
