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A Game Courier Preset for Sissa

This rule-enforcing preset was created through the Play-Test Applet

R N B Q K S B N R P P P P P P P P P p p p p p p p p p r n b s k q b n r

Sissa

Legal moves displayed. Might enforce rules.

Welcome to Game Courier, where you can play Sissa and many other Chess variants through online correspondence.


Rules of Sissa

In general all the rules of standard chess are applied here.

When castling the King steps three squares toward either Rook.

The Bishops Conversion Rule holds.

Both bishops of each player cannot run along squares of the same color. One of them must change in such a manner that it transits through squares of the other color. Being in its original square without having been moved before, it will take an orthogonal step towards any of the 3 surrounding squares that are of the other color, provided that these are empty. This special move is called conversion and it must be done as an ordinary move during the game.

In the following diagram the g1-bishop may make the conversion by moving towards either f1 or g2 or h1.

conversion

A player may choose which bishop he converts, but if he makes a normal move with one of them, then the first move made with the other must be a conversion move; and, viceversa, if he first makes a conversion move with one, then the other will have to be moved normally. Thus, a player never can make more than one conversion move in a game, and a promoted bishop does not make conversion moves. It is possible to take a piece of the opponent by conversion. If both bishops are in their original squares without having been moved before and one of them is captured, then the other will retain the option of being converted or move normally according to the color of the square in which it is located.

[pc _MLV_SI Sissa]Sissa moves each time as Rook AND Bishop following a movement pattern of the form nR+nB or nB+nR, where n is any whole number.

nR+nB means "first n squares like Rook followed by n squares like Bishop";

nB+nR means "first n squares like Bishop followed by n squares like Rook".

Then, if for instance n=5, Sissa MUST MOVE 5 squares as Rook followed by 5 squares as Bishop or viceversa.

There is no restriction on the movement direction of the second stage respecting to the first.

Sissa doesn't leap. All squares it passes by must be empty.

The following diagram illustrates its way of movement:


sissa

From c3, Sissa can reach the squares marked with green circlets by moving nightrider-wise; squares marked with red circlets are reached by moving rook-wise. 

The i6 square is reached by c3-f3-i6. The c3-f6-i6 path is obstructed by the Blue's King. Likewise, f9 is reached via c3-f6-f9, not by c3-c6-f9 that is obstructed by the Bishop.

c8 is reached via c3-h3-c8, not via c3-h8-c8 that is obstructed by the g8-Pawn; c1 is reached via c3-a1-c1 or via c3-a3-c1 but not by c3-e3-c1 nor c3-e1-c1 that are both obstructed by the d2-Pawn.

a2, a4, b5, d5 and e4 can be reached by moving either like Mao or like Moa; b1 only like Moa; d1 is inaccessible due to the obstruction of White's King and d2-Pawn.   

Concluding, the Bishop can be captured by 4 paths: c3-e3-c5 or c3-e5-c5 or c3-a3-c5 or c3-a5-c5. The Queen can only be captured by c3-e5-e7 since c3-c5-e7 is obstructed by the Bishop.

How to Move Pieces

Full Algebraic Notation

Algebraic notation identifies each space by a coordinate that begins with its file label and ends with its rank label. On the Chess board, files go up and down from one player to the other, and ranks go from left to right. In most games, files are represented by letters, and ranks are represented by numbers, but there is no fixed rule requiring this for all games, and some games, such as Shogi, reverse this convention. If you look at the diagram, you will usually see the file labels going from left to right and the file labels going up and down. And if you hover your mouse over a space, you will normally see the name of the coordinate appear in a tooltip.

It is not uncommon to see algebraic notation being used for Chess, but it is often in an abbreviated format that requires you to know both the rules of the game and the current position to know exactly which piece moves where. For example, the notation "Ne6" indicates that a Knight is moving to e6, but it doesn't indicate which Knight, and it doesn't specify where the Knight is coming from. To figure this out, you need to know how a Knight moves and which Knight on the board can make a legal move to e6.

Although rules may be programmed for individual games, Game Courier itself does not know the rules of any game, and it is unable to parse abbreviated algebraic notation. Therefore, it relies on full algebraic notation, which completely specifies the move without requiring any knowledge of the game's rules or the current position. The most usual type of full algebraic notation indicates the piece that is moving by its label, the space it is moving from, and the space it moving to. In Chess, a typical first move might be written as "P e2-e4". When you hover your mouse over a piece, you will normally see the piece label followed by the coordinate for the space, and when you hover it over an empty space, you will normally see the coordinate label. Including the piece label in your notation allows Game Courier to check that the piece you're moving is the right one, and it makes game notation easier to follow, but it is not mandatory.

You may promote a piece by including a promotion move after your regular move. A promotion move has a piece go directly to a coordinate. Here is an example: "p e7-e8; q-e8".

You may remove a piece from a space by adding an @ to the space or by omitting the destination coordinate. For example, both "@-e4" and "e4-" would remove the piece on "e4". This is useful for en passant when you are playing a game that does not handle this automatically. For example, "P d5-e6; e5-" removes the Pawn on e5 after a Pawn moves from d5 to e6.

You will not need to remove spaces for most games, but if you should need to, you can do this by omitting the first coordinate in a move. For example, "-e4" would remove e4 from the board. To add or return a space to the board, you may add an @ or any other piece to it.

Available Pieces

Pieces are represented by labels, usually using uppercase letters for White and lowercase letter for Black. When you enter a move or specify the starting position for a game, you should remember that piece labels are case-sensitive. Many piece sets are available for use with Game Courier, and this table shows you which pieces belong to the piece set you are currently using.

These pieces come from a set containing more pieces, but this preset has had the set of pieces reduced to those used in the game.

wbishop.gif
B
wking.gif
K
wknight.gif
N
wpawn.gif
P
wqueen.gif
Q
wrook.gif
R
../alfaeriemisc/lavallee/wsissa2.gif
S
bbishop.gif
b
bking.gif
k
bknight.gif
n
bpawn.gif
p
bqueen.gif
q
brook.gif
r
../alfaeriemisc/lavallee/bsissa2.gif
s

Credits

This preset uses the short-enforced settings file for Sissa, which was made by Carlos Cetina.

Game Courier was created, programmed and written by Fergus Duniho.

Game Courier, Copyright © Fergus Duniho, 2001-2017


WWW Page Created: 15 August 2001