/**
* This function will generate getRandomTurnCount() number of non cancelling,
* random turns. If a puzzle wants to provide custom scrambles
* (for example: Pochmann style megaminx or MRSS), it should override this method.
*
* NOTE: It is assumed that this method is thread safe! That means that if you're
* overriding this method and you don't know what you're doing,
* use the synchronized keyword when implementing this method:<br>
* <code>protected synchronized String generateScramble(Random r);</code>
* @param r An instance of Random
* @return A PuzzleStateAndGenerator that contains a scramble string, and the
* state achieved by applying that scramble.
*/
public virtual PuzzleStateAndGenerator GenerateRandomMoves(Random r)
{
var ab = new AlgorithmBuilder(MergingMode.NoMerging, GetSolvedState());
while (ab.GetTotalCost() < GetRandomMoveCount())
{
var successors = ab.GetState().GetScrambleSuccessors();
try
{
string move;
do
{
move = Functions.Choose(r, successors.Keys);
// If this move happens to be redundant, there is no
// reason to select this move again in vain.
successors.Remove(move);
} while (ab.IsRedundant(move));
ab.AppendMove(move);
}
catch (InvalidMoveException e)
{
Assert(false, e.Message, e);
return(null);
}
}
return(ab.GetStateAndGenerator());
}
public static PuzzleStateAndGenerator ApplyOrientation(CubePuzzle puzzle, CubeMove[] randomOrientation,
PuzzleStateAndGenerator psag, bool discardRedundantMoves)
{
if (randomOrientation.Length == 0)
{
return(psag);
}
// Append reorientation to scramble.
try
{
var ab = new AlgorithmBuilder(MergingMode.NoMerging, puzzle.GetSolvedState());
ab.AppendAlgorithm(psag.Generator);
// Check if our reorientation is going to cancel with the last
// turn of our scramble. If it does, then we just discard
// that last turn of our scramble. This ensures we have a scramble
// with no redundant turns, and I can't see how it could hurt the
// quality of our scrambles to do this.
var firstReorientMove = randomOrientation[0].ToString();
while (ab.IsRedundant(firstReorientMove))
{
//azzert(discardRedundantMoves);
var im = ab.FindBestIndexForMove(firstReorientMove, MergingMode.CanonicalizeMoves);
ab.PopMove(im.Index);
}
foreach (var cm in randomOrientation)
{
ab.AppendMove(cm.ToString());
}
psag = ab.GetStateAndGenerator();
return(psag);
}
catch (InvalidMoveException e)
{
Assert(false, e.Message, e);
return(null);
}
}