Clarify/implement rules for >2 players

[ElTh0r0]

From #8

nDirection is dynamic (but only relevant for >2 players as the direction changes if a player must pass).

Aha. I hadn't read up on the 3-player rules before. But are you sure that the direction can change? From the rules here:

In the case where the current player has no move available, the right to move is given back to the previous player, which means effectively the turn order is changed once to anti-clockwise.

The way I interpret this is that if it is player 2's turn (for example), and he has only moves that would let player 3 win, he must pass and play transfers back to player 1, but the word “once” here suggests that this doesn't permanently change the direction of play. So from player 1's perspective, the next player is always player 2.

Thanks for pointing that out! I think you are right and I missed the word "once" 🙂
But I'll double check it one more time and will take care of it!

[maksverver]

The three-player rules are a bit strange. How I interpret them is that it's illegal for a player to make any move that would allow the next player to win.

As a consequence, it is impossible for any player to win on their own turn. Because if they could, then the previous player's move would by definition have been invalid. So the only way to win as (say) player 1 is by creating a situation where player 2 has no moves except those that would allow player 1 or player 3 to win. In that case, letting player 3 is illegal, and he must let player 1 win instead.

The rules for three players as currently implemented in stack-and-conquer differ on two points:

1. The rule that forbids building a tower for your opponent is technically too strict: it should only be disallowed to build a tower for the next player, not the previous one (note the word “next” in “However, all moves that would result in an instant win for the next player are not available. ”). The distinction is not really important, however, because if you disallow player 2 from building a tower for player 1, and simply pass the turn to player 1 instead, then player 1 will make the same winning move on his own turn, and the outcome is the same.

2. Moves that allow the next player to win, by leaving them a winning move, should also be forbidden, but currently, they aren't. This seems more important.