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Relocation Chess. Swap a pair of your own pieces before you begin. With Fischer Random castling rules.[All Comments] [Add Comment or Rating]

H. G. Muller wrote on Sat, May 2, 2009 02:42 PM UTC:

Is '2' a legal value in the Setup tag? I thought this was a Boolean, limited to '0' and '1'. 

I think it is a bad idea to leave the actual swaps out of the PGN. They are part of the game. Especially in variants that allow several such swaps (e.g. Superchess), so the order cannot be deduced from the position after the swapping phase (as could be given by FEN).

So I propose the FEN tag should really be reserved for cases where the players get to play a non-standard position without having any say in it, i.e. in true shuffle variants. For variants like reocation Chess, we need to define a notation for swap moves.

I propose to write the swap moves in SAN as non-capture moves to an occupied square. E.g. 1. Kg8 would mean black swaps its King with the Knight on g8. In full algebraic notation this would be Ke8-g8. This could also work in Superchess, where swaps take place with pieces in the holdings: they could be written as drops to an occupied square. E.g. A@d1 would mean you swap the Queen for an Amazon, the Queen going back into the holdings. (Note that the way I implemented Superchess in WinBoard makes it a normal shuffle variant, where the players have no say in how they make swaps to create the initial position, so this does not apply there.)