A Game Courier Preset for Modern Chaturanga
Rules of Modern Chaturanga
Modern Chaturanga:- Original ashtapada board, with Indian markings.
- Alternate uncheckered plain board (without ashtapada markings)
Modern Chaturanga is based on Henry A. Davidson's variation of Chaturanga, as described in his 1949 book: A Short History of Chess, but with new promotion rules:
- Pawns promote to Counselors (Ferz) upon reaching their 6th rank, like they would promote in Makruk.
- Counselors themselves promote to Generals (like a Man from Courier Chess) when they arrive to their 8th rank. This rule is inspired by the stronger promotion rule in Joe Joyce's Modern Shatranj.
This preset enforces all rules.
Summary of the rules:
- The object of the game is to capture or Bare the opponent's King.
- Bare King counts as a loss for the lone King, provided the latter cannot also bare his/her opponent's King on the very next move. Two bare Kings count as a draw.
- There is no checkmate or stalemate.
- Kings move like in orthodox chess, one square in any direction. However, unlike in chess, Kings are allowed to move into "check" and risk being captured.
- Generals move like Kings, one square in any direction, but they are not royal.
- Counselors move only one square diagonally, like a Ferz. They promote to Generals upon reaching their 8th rank.
- Elephants move like Burmese Elephants, Makruk Bishops or Shogi Silver Generals (one square either diagonally or straight forward).
- Pawns move and capture just like their Orthodox Chess counterparts; one step foward for movement and diagonally to capture. Pawns do not have a 2-step initial move, consequently there is no en passant rule. Pawns promote upon reaching their 6th rank to Councelors (Ferz), like they would in Makruk.
- Knights and Rooks move like in orthodox Chess.
- There is no castling rule.
Why in the world would Kings be allowed to put themselves into "check" and risk being captured?
Henry A. Davidson must have believed that this option was available in India for at least four possible reasons:
1. Blunders - A player making such a mistake, carelessly putting his/her King into check deserves to lose the game. Plain and simple!
2. Surrender - Instead of resigning, players whose position is hopeless may choose to surrender their forces with honor by sacrificing their King.
3. and 4. are that since (according to Davidson) checkmate and stalemate were Persian concepts previously unknown in India, there had to be a way for games to continue to an end when either of these two "Persian" situations arose in play. See the diagrams below:
Sample "Persian" checkmate and stalemate situations in Chaturanga
Should the above situations arise in Chaturanga, according to Davidson, the game would need to carry on, and black would be forced to play on. Therefore:
In the board on the left, black (who is in check) would need to play with any of his pieces (including the King), and white would formally end the game with his/her next move: QxK# (if black played Ka7 or Kc7) or RxK# (for any other black move).
In the case of the diagram in the right, black is not in check, but given that he/she is forced to move (stalemates didn't exist according to Davidson), then any King move will put him in check, and white will promote to queen and win with either PxK=Q# (if black played Kd8 or Kf8), or KxK# (should black play Kd7, Kxe7 or Kf7).
In the notation above, the checkmate symbol "#" is used to represent a King's capture.
In the diagram above left (which is after 1.Rf8+) since in this variation the Kings can remain in check, black might as well play: 1... Qc2+! Now both Kings are in check, and should white blunder and not capture the enemy king, black could have the 2... QxK# option available.
Notes about this preset:
- This preset detects when a King has been captured, which ends the game.
- This preset enforces the Bare King rule as follows:
- Lone King versus King + 2 (or more) pieces: automatic loss for the lone King.
- Lone King versus Lone King: automatic draw.
- Lone King versus King + 1 piece: The Lone King will be allowed one more move. If the lone King does not bare the opponent on this additional move: automatic loss for the lone King.
- This preset warns players when they are in "check", but it will not force the player to move out of check, as King captures were part of the Indian game according to Davidson.
- However, when a traditional "checkmate" or "stalemate" situation arises, this preset will only warn players that they must play on, as the game must ultimately end with a King capture.
- Alternately, players may end the game with the Game Courier commands: resign or drawn, as applicable.
Read more about Chaturanga here.
Game Courier Logs
Game Courier Logs for Games of Chaturanga VariationsHow 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.
Credits
This preset uses the Alfaerie2 settings file for Modern Chaturanga, which was made by Jose Carrillo.
Game Courier was created, programmed and written by Fergus Duniho.
Game Courier, Copyright © Fergus Duniho, 2001-2017
WWW Page Created: 15 August 2001