- Sashité for Developers
- Glossary
Glossary
This glossary defines the core terminology used across the Sashité ecosystem: the Game Protocol (structural model), Rule Systems (game-specific legality), and generic notation systems.
Note: The Protocol defines structure and invariants. The Rule System defines what is legal and how outcomes are evaluated.
1. Core game entities
| Term | Definition |
|---|---|
| Game | A ruleset describing how a Match starts, how Positions evolve through Moves, and how play ends (win / loss / draw / other). |
| Rule System | The complete game-specific rule layer expressed on top of the Game Protocol (legality, evaluation, outcomes, auxiliary state). |
| Game Protocol | The minimal structural framework that defines Pieces, Locations, Positions, Actions, and Moves, plus invariants for state transitions. |
| Player | A human or agent participating in a Match. |
| Side | A camp label. In the base protocol there are exactly two Sides: first and second. |
| Player Side | The Side assigned to a Player for the duration of a Match. This mapping is fixed. |
| Piece Side | The Side attribute of a Piece at a given moment. A Rule System may allow Piece Side to change over time. |
| Style | A movement tradition or family label (e.g., chess, shogi, xiangqi). In a given Match, exactly one or two Styles are in use (since each of the two Players has a fixed Player Style, which may be identical or different). |
| Player Identity | The tuple (Player Side, Player Style) that characterizes a Player’s fixed identity for the duration of a Match. |
| Player Style | The Style assigned to a Player for the duration of a Match. This mapping is fixed. A Player Style does not constrain which Piece Styles that player’s pieces may have. |
| Piece Style | The Style attribute of a Piece at a given moment. A Rule System may allow Piece Style to differ from Player Style, or to change over time. |
| First Player | The Player assigned to Side first for the whole Match. |
| Second Player | The Player assigned to Side second for the whole Match. |
| Active Player | The Player whose turn it is in the current Position. Exactly one player is Active at any time. |
| Inactive Player | The other Player in the current Position. |
2. Board, locations, and pieces
| Term | Definition |
|---|---|
| Board | The shared spatial structure containing addressable Squares (geometry defined by the Game or notation). |
| Square | A Board Location that can hold at most one Piece, or be empty. |
| Hand | A multiset of Pieces held off-board by a specific Player (two hands exist: first/second). Order is not meaningful at protocol level. |
| Location | Any place a Piece may exist under the Game Protocol: a Square, the First Player Hand, or the Second Player Hand. |
| Piece | An individual entity with identity attributes and exactly one Location. Pieces are not created or destroyed at protocol level. |
| Piece Name | A type identifier within a Game (e.g., king, rook, pawn). Semantics are Rule System-defined. |
| Piece State | A discrete, Rule System-defined attribute describing internal status (e.g., unpromoted/promoted, enhanced/diminished). |
| Piece Identity | The tuple (Piece Side, Piece Name, Piece State, Piece Style, Terminal Status) that characterizes a Piece’s functional identity. |
| Terminal Piece | A distinguished Piece whose presence/condition/capacity determines whether play can continue, as defined by the Rule System. |
| Terminal Piece Status | A Rule System-defined label describing a Terminal Piece situation (e.g., threatened, blocked). Game outcomes are derived from these statuses. |
| Captured Piece | A Rule System concept usually modeled protocol-wise as a displacement Board → Hand. |
| Drop / Placement | A Rule System concept usually modeled protocol-wise as a displacement Hand → Board. |
3. Positions, actions, and moves
| Term | Definition |
|---|---|
| Position | A protocol-level snapshot: every Piece’s Location and identity attributes, plus the current Active Player. |
| Initial Position | The first Position of a Match (defined by the Game, Rule System, or notation). |
| Position Identity | The equivalence class of a Position under canonical representation (same Pieces+attributes in same Locations, same Active Player). |
| Canonical Position Representation | A deterministic encoding used for equality checks (the exact format is system-defined). |
| Action | The smallest atomic transformation affecting at most one Piece: a Displacement and/or Mutation. |
| Displacement | The part of an Action that changes a Piece’s Location. Only Board→Board, Board→Hand, Hand→Board are allowed. |
| Mutation | The part of an Action that changes one or more identity attributes (Side/Name/State/Style), with or without movement. |
| Move | An ordered finite sequence of zero or more Actions performed by the Active Player in one turn. |
| Pass Move | A Move with zero Actions that only toggles the Active Player (if allowed by the Rule System). |
| Turn | One opportunity for the Active Player to execute exactly one Move. |
| Ply | One Move by a single player (one step of time progression). |
4. Matches and game-level notions
| Term | Definition |
|---|---|
| Match | A concrete run of a Game: a finite sequence of Positions starting from an Initial Position and evolving through Moves. |
| History | The ordered list of Moves (and optionally Positions) played so far. |
| Game State | The current Position plus Rule System-maintained auxiliary data (clocks, counters, repetition tracking, terminal evaluation, etc.). |
5. Legality and protocol validity
| Term | Definition |
|---|---|
| Protocol-Valid Move | A Move that satisfies protocol structure and invariants (allowed displacement patterns, conservation, exclusivity, correct turn toggle). |
| Pseudo-Legal Move | A Move that is protocol-valid and respects basic movement patterns, but may still violate higher-level constraints (e.g., terminal restrictions, repetition rules). |
| Legal Move | A Move that is protocol-valid and fully compliant with the Rule System in the current Game State. |
6. License
This specification is made available under the terms of the Open Web Foundation Agreement 1.0 (OWFa 1.0).
The authoritative legal text is the OWF “Final Specification Agreement (OWFa 1.0)”.