Variant Playing Engines

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Richard Allbert
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Variant Playing Engines

Post by Richard Allbert »

After getting my engine running on a Pi Zero on the ICC server, I've been adding various wild variants to it.

Is there a list of variant playing engines somewhere? Specifically for losers and giveaway.

I've been using Sjeng, which compiled ok for Linux, but it would be nice to have some more.

FairyMax doesn't play losers and giveaway :(
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hgm
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Re: Variant Playing Engines

Post by hgm »

To do well for Losers and Giveaway requires a completely different engine, based on proof-number search rather than alpha-beta. Fairy-Max is limited to Chess-like games, where the goal is to capture a royal piece. It started as merely a tool for empirical determination of the value of fairy pieces in such games. So it is very versatile in handling weird piece moves, but hardly allows any other rule changes. Version 5.0, which I released last month, is the first one that can handle a deviating board depth.

Pulsar plays all ICC variants. But I don't think it is open source.
Alexander Schmidt
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Re: Variant Playing Engines

Post by Alexander Schmidt »

Richard Allbert wrote:After getting my engine running on a Pi Zero on the ICC server, I've been adding various wild variants to it.

Is there a list of variant playing engines somewhere? Specifically for losers and giveaway.

I've been using Sjeng, which compiled ok for Linux, but it would be nice to have some more.

FairyMax doesn't play losers and giveaway :(
The best list I am aware of is this one:

http://computer-chess.org/doku.php?id=c ... ngine_list
Richard Allbert
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Re: Variant Playing Engines

Post by Richard Allbert »

Alexander Schmidt wrote:
The best list I am aware of is this one:

http://computer-chess.org/doku.php?id=c ... ngine_list
Great thanks :)
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Evert
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Re: Variant Playing Engines

Post by Evert »

SjaakII plays a ton of different variants, but not Suicide (or any of its close relatives). It could play a legal game if I finish implementing "captures are compulsory", but it'll play poorly.
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Nordlandia
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Re: Variant Playing Engines

Post by Nordlandia »

In which variants is Commonder featured in latest Fairy Max 5.0b version.

I can only find Knightmate.
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hgm
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Re: Variant Playing Engines

Post by hgm »

Courier Chess also features a Commoner. The newly added variant Roman Chess actually has two (called Archers). But in contrast to what its name suggests, the piece is not that common! :lol:

I used a Commoner in a Chess variant I designed myself, Elven Chess. (Each side also has two there, and they are called Dwarfs.) But Fairy-Max cannot do Elven Chess, because the latter also contains a piece that can do double captures (the Chu-Shogi Lion, called Warlock in that game), which is beyond Fairy-Max' capabilities.

Commoners are quite interesting pieces, and it is a pity they are not used more often. For example, the end-game KC-KC contains an amazing number of lengthy wins, for a symmetric end-game (which usually are dead draws). But when one side can prevent the other's K and C to connect, he can gang up against the opponent's K, leaving the C helplessly watching in his back. K+C versus bare K is always won on any board upto 14x14.
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Evert
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Re: Variant Playing Engines

Post by Evert »

There's also "viceroy chess", which is orthohess with promotion by file-piece. Promotion on the e-file is to commoner (called viceroy in this game).

Of course in practice that means it hardly ever shows up on the board.
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Nordlandia
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Re: Variant Playing Engines

Post by Nordlandia »

hgm wrote:Courier Chess also features a Commoner. The newly added variant Roman Chess actually has two (called Archers). But in contrast to what its name suggests, the piece is not that common! :lol:

I used a Commoner in a Chess variant I designed myself, Elven Chess. (Each side also has two there, and they are called Dwarfs.) But Fairy-Max cannot do Elven Chess, because the latter also contains a piece that can do double captures (the Chu-Shogi Lion, called Warlock in that game), which is beyond Fairy-Max' capabilities.

Commoners are quite interesting pieces, and it is a pity they are not used more often. For example, the end-game KC-KC contains an amazing number of lengthy wins, for a symmetric end-game (which usually are dead draws). But when one side can prevent the other's K and C to connect, he can gang up against the opponent's K, leaving the C helplessly watching in his back. K+C versus bare K is always won on any board upto 14x14.
Why isn't it possible to promote to other pieces than Queen in Knightmate.

Also i can't figure out how Fairy Max can use all cores instead of default 1 in winboard 4.8.
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Evert
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Re: Variant Playing Engines

Post by Evert »

Nordlandia wrote:
hgm wrote:Courier Chess also features a Commoner. The newly added variant Roman Chess actually has two (called Archers). But in contrast to what its name suggests, the piece is not that common! :lol:

I used a Commoner in a Chess variant I designed myself, Elven Chess. (Each side also has two there, and they are called Dwarfs.) But Fairy-Max cannot do Elven Chess, because the latter also contains a piece that can do double captures (the Chu-Shogi Lion, called Warlock in that game), which is beyond Fairy-Max' capabilities.

Commoners are quite interesting pieces, and it is a pity they are not used more often. For example, the end-game KC-KC contains an amazing number of lengthy wins, for a symmetric end-game (which usually are dead draws). But when one side can prevent the other's K and C to connect, he can gang up against the opponent's K, leaving the C helplessly watching in his back. K+C versus bare K is always won on any board upto 14x14.
Why isn't it possible to promote to other pieces than Queen in Knightmate.

Also i can't figure out how Fairy Max can use all cores instead of default 1 in winboard 4.8.
You should be able to promote to other pieces just fine (but F-Max probably doesn't consider it). There is no way to make it use more than a single core.