SgPointSet SpUtil::GetRelevantMoves(GoBoard& bd, SgBlackWhite toPlay,
bool useFilter)
{
SgPointSet legal;
for (SgSetIterator it(bd.AllEmpty()); it; ++it)
if (bd.IsLegal(*it))
legal.Include(*it);
if (! useFilter)
return legal;
GoSafetySolver safetySolver(bd);
SgBWSet safe;
safetySolver.FindSafePoints(&safe);
SgBlackWhite opp = SgOppBW(toPlay);
SgPointSet moves;
const GoRules& rules = bd.Rules();
const bool captureDead = rules.CaptureDead();
//const bool japaneseScoring = rules.JapaneseScoring();
for (SgSetIterator it(legal); it; ++it)
{
SgPoint p = *it;
const bool isSafe = safe[toPlay].Contains(p);
const bool isSafeOpp = safe[opp].Contains(p);
const bool hasOppNeighbors = bd.HasNeighbors(p, opp);
if ( (! isSafe && ! isSafeOpp)
|| (isSafe && captureDead && hasOppNeighbors)
// || (isSafeOpp && ! japaneseScoring)
)
moves.Include(p);
}
return moves;
}
bool GoEyeUtil::IsSinglePointEye(const GoBoard& bd, SgPoint p,
SgBlackWhite color)
{
SG_ASSERT(bd.IsEmpty(p));
const SgBlackWhite opp = SgOppBW(color);
if (bd.HasEmptyNeighbors(p) || bd.HasNeighbors(p, opp))
return false;
if (bd.Line(p) == 1)
return ! (bd.HasDiagonals(p, SG_EMPTY) || bd.HasDiagonals(p, opp));
return (bd.NumDiagonals(p, SG_EMPTY) + bd.NumDiagonals(p, opp)) <= 1;
}
