riichi-tools-rs

A tool library for riichi mahjong written in Rust, made mostly to be used as a WASM component.

Lots of inspiration from other mahjong tools, like https://euophrys.itch.io/mahjong-efficiency-trainer, http://tenhou.net/2/, http://kobalab.net/majiang/dapai.html etc.

Showcase / frontend of this library can be found at https://riichi.harphield.com/tools/

Shanten and Uke-ire modes

There are two implementations of shanten and uke-ire calculations available. The default one is slower, but doesn't use any lookup tables, so it creates a smaller binary: ideal for WASM.

The other one is a port from Spines.Mahjong and is a lot faster, but the binary is larger.

You can enable the faster mode with enabling the feature in your cargo.toml:

riichi-tools-rs = { version = "0.0.70", features = ["fast_shanten"] }

Roadmap

• South 4 Simulator
  • A game where you try to win in the last round [DONE] [moved to a separate project, riichi-tools-wasm]
• Hand analysis
  • Shanten for 13 tiles [DONE]
  • Shanten for 14 tiles with complete hand indication [DONE]
  • Ukeire, tile acceptance [DONE]
  • Hand value + yaku for complete hand (14 tiles) [DONE]
  • Hand value + yaku for tenpai hand with possible outcomes [DONE]
  • All of the above also for hands with calls [DONE]
  • Rule variants (Tenhou vs WRC vs MahjongSoul etc.)
• Table analysis
  • Safe tiles
  • Wait probability percentages
• Replay analysis
  • Tenhou replay parsing
  • Majsoul replay parsing
  • Discard rating

Hand representation parsing

Hand::from_text() method accepts a string representation in the following format:

• 1-9 m, s or p for manzu, souzu and pinzu tiles
• 0 m, s or p are red 5 (support is mostly WIP at the moment)
• 1-7 z for honor tiles, where
  • 1 = east
  • 2 = south
  • 3 = west
  • 4 = north
  • 5 = white dragon
  • 6 = green dragon
  • 7 = red dragon
• Open shapes
  • (XYZCI) is chi, where XYZ are consecutive numbers, C is the color (m, p, s) and I is the index of the called tile (0-2).
  • (pXCIr) is pon, where X is 0-9, C is the color (m, p, s, z) and I is the index of the player from who we called (1 = shimocha, 2 = toimen, 3 = kamicha). In case the pon has a red 5, the representation will use 0 - for example (p0m2). If it was the red 5 that was called, r is added
  • (kXCIr) is closed kan or daiminkan (open called kan). Same rules as pon apply, but I is optional - if not available, the kan is considered closed.
  • (sXCIr) is a shouminkan (added kan). Same rules as daiminkan above.

Some examples:

• 123m44456888s678p
• 456s11133z(456m1)(456p0)
• 4z(p1z1)(k2z)(s3z3)(p6z2)