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The Consuls. Chess with two Kings and Pawns that can capture as Bishop, Knight, and Rook on the enemy side.[All Comments] [Add Comment or Rating]
Albert Lee wrote on 2021-07-11 UTC

I just added description and links to a smaller variant of The Consuls on a 4x4 board in the Notes section.


Albert Lee wrote on 2021-07-11 UTC

Thanks for your effort, much appreciated!


H. G. Muller wrote on 2021-07-11 UTC

Ah yes, I mixed it up. Fixed that now.

There still is a problem in the notation. Because the diagram doesn't support location-dependent moving, I implemented it through automatic non-standard promotion through a small additional script embedded in the page, which defines a function WeirdPromotion. And defined 5 different Pawn types, which all promote depending on the rank they land on.

But the SAN generator adds a promotion suffix when the type after the move isn't the same as before the move, and all the 5 Pawn types currently havetheir ID defined as P. So the promotion suffix is ambiguous, and this might lead to problems when, on pasting a game, the diagram encounters a move like e5=P. Besides, in the context of this game it looks silly to have promotion suffixes, when promotion is automatic. Not sure how I can address that in general, though.

[Edit]

The notation problem seems solved. I now suppress writing a promotion suffix when the promoted piece has the same ID as the original piece, even when it actually is a different piece type. In principle the SAN generator + parser should be resistant against different piece types having the same ID; its decision to add disambiguators is not based on the piece type, but the piece ID. So if two pieces that have the same ID can move to the same square, it will add the disambiguator necessary to distinguish the moves. Such ambiguous piece labeling cannot work if the ID appears as a promotion suffix, though; the SAN parser would always take it to be the first piece type (in the legend table) that has that ID. But if there is no promotion suffix, and the only pseudo-legal move with the specified piece to the specified square is a promotion, the SAN parser will interpret the move as that promotion even in the absence of a promotion suffix.

This should in general allow position-dependent moving to be emulated through a custom promotion routine switching the type between types with the same ID, in a transparent way. The only peculiarity here is that the piece with position-dependent move is a Pawn, and that only the first alternative will get the P suppressed in the move notation. The alternative Pawn types will all specify the P in their move notation. E.g.

1. e4 h5 2. e5 h4 3. Pe6 f5 4. Pxf5 Ph3 5. Pf6 Pxg2 6. Pxg7


Albert Lee wrote on 2021-07-11 UTC

Thank you for creating this playable version!

I noticed that the Pawn promotion rules for Knight and Bishop are swapped. This is the supposed order of promotion which follows the sequence of the initial arrangement of pieces on the back rank: King, Bishop, Knight, and Rook.


H. G. Muller wrote on 2021-07-10 UTC
satellite=consul files=8 ranks=8 graphicsDir=/graphics.dir/alfaeriePNG/ whitePrefix=w blackPrefix=b promoZone=0 maxPromote=0 squareSize=50 graphicsType=png lightShade=#CCCC11 darkShade=#339933 rimColor=#111199 coordColor=#CCCC11 borders=0 firstRank=1 useMarkers=1 extinction=0 pawn::::a2-h2 pawn::cKfW:: pawn::cBfmW:: pawn::cNfmWfcF:: pawn::cRfWfcF:: knight:N:::b1,g1 bishop::::c1,f1 rook::::a1,h1 king::KisO2::d1,e1

The Consuls


Fergus Duniho wrote on 2021-07-09 UTC

Okay, I have published this to the site.


Albert Lee wrote on 2021-07-09 UTC

Hi Fergus, thanks for your comment.

I have changed the description of the Pawn promotion rules from the point of view of the player who is promoting - 5th, 6th, 7th, and 8th ranks.


Fergus Duniho wrote on 2021-07-08 UTC

Your description of Pawn promotion is a bit unintuitive. You describe it in terms of 1st through 4th ranks. Since I presume that promotion would be on the 1st through 4th ranks of the opponent, it would seem to say that a Pawn can move as a Rook on its player's 5th rank, as a Knight on a player's 6th rank, as a Bishop on a player's 7th rank, and as a King on a player's 8th rank. But the other order seems like it might be what you intend, since it allows slower and less powerful types of promotion before allowing quicker and more powerful types. So, please clarify promotion in terms of the ranks of the player who is promoting.


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