private double PrivateStrategyNextPiece
(
STBoard board,
STPiece piece,
STPiece.STPieceShape nextPieceShape, // None == no piece available or known
ref int bestRotationDelta, // 0 or {0,1,2,3}
ref int bestTranslationDelta // 0 or {...,-2,-1,0,1,2,...}
)
{
if (false == piece.IsValid( ))
{
return(0.0);
}
int currentBestTranslationDelta = 0;
int currentBestRotationDelta = 0;
double currentBestMerit = (-1.0e20);
int currentBestPriority = 0;
int trialTranslationDelta = 0;
int trialRotationDelta = 0;
double trialMerit = 0.0;
int trialPriority = 0;
int maxOrientations = 0;
bool moveAcceptable = false;
int count = 0;
STBoard tempBoard = new STBoard();
STPiece tempPiece = new STPiece();
maxOrientations = STPiece.GetMaximumOrientationsOfShape(piece.GetShape());
for
(
trialRotationDelta = 0;
trialRotationDelta < maxOrientations;
trialRotationDelta++
)
{
// Make temporary copy of piece, and rotate the copy.
tempPiece.CopyFrom(piece);
for (count = 0; count < trialRotationDelta; count++)
{
tempPiece.Rotate();
}
// Determine the translation limits for this rotated piece.
bool moveIsPossible = false;
int minDeltaX = 0;
int maxDeltaX = 0;
board.DetermineAccessibleTranslationsForPieceOrientation
(
tempPiece,
ref moveIsPossible, // false==NONE POSSIBLE
ref minDeltaX, // Left limit
ref maxDeltaX // Right limit
);
// Consider all allowed translations for the current rotation.
if (true == moveIsPossible)
{
for
(
trialTranslationDelta = minDeltaX;
trialTranslationDelta <= maxDeltaX;
trialTranslationDelta++
)
{
// Evaluate this move
// Copy piece to temp and rotate and translate
tempPiece.CopyFrom(piece);
for (count = 0; count < trialRotationDelta; count++)
{
tempPiece.Rotate();
}
tempPiece.Translate(trialTranslationDelta, 0);
moveAcceptable =
board.DetermineIfPieceIsWithinBoardAndDoesNotOverlapOccupiedCells
(
tempPiece
);
if (true == moveAcceptable)
{
// Since the piece can be (not necessarily GET) at the goal
// horizontal translation and orientation, it's worth trying
// out a drop and evaluating the move.
tempBoard.CopyFrom(board);
tempBoard.FullDropAndCommitPieceToBoard(tempPiece);
trialPriority = 0;
// Okay, now do second move with "Next Piece"
int nextPieceBestRotation = 0; // Dummy variable
int nextPieceBestTranslation = 0; // Dummy variable
STPiece nextPiece = new STPiece();
nextPiece.SetShape(nextPieceShape);
nextPiece.SetX(tempBoard.GetPieceSpawnX());
nextPiece.SetY(tempBoard.GetPieceSpawnY() - 1);
nextPiece.SetOrientation(1);
trialMerit =
PrivateStrategy
(
true, // Not just a single ply; We are calling from a parent ply.
tempBoard,
nextPiece,
ref nextPieceBestRotation,
ref nextPieceBestTranslation
);
// If this move is better than any move considered before,
// or if this move is equally ranked but has a higher priority,
// then update this to be our best move.
if (
(trialMerit > currentBestMerit) ||
((trialMerit == currentBestMerit) && (trialPriority > currentBestPriority))
)
{
currentBestPriority = trialPriority;
currentBestMerit = trialMerit;
currentBestTranslationDelta = trialTranslationDelta;
currentBestRotationDelta = trialRotationDelta;
}
}
}
}
}
// Commit to this move
bestTranslationDelta = currentBestTranslationDelta;
bestRotationDelta = currentBestRotationDelta;
return(currentBestMerit);
}
