From-scratch reimplementation of the Sword of the Stars (2006) engine. Clean-room; engine code only — bring your own game copy. Planning/RE evidence live in sots-re.
3ca010978c
Adds the half of the AI's turn that is arithmetic rather than judgement: what an
order looks like in the command block, which orders advance the save's
modification counter and by how much, and the phase/pass skeleton the decisions
hang in.
The counter's per-command cost turns out to have a sharp boundary. Applying an
element of command lists 1..16 advances it; applying an element of lists 17..27
does not, and one of the six flag-gated single commands is free as well. So a
uniform per-element cost model is wrong on any turn that touches the free half.
Two behaviours here are not conveniences and change the output:
* every submitted block costs at least one, because the send-buffer build sets
the research-rate gate unconditionally whatever the player did. On a quiet
board that is the largest term in the turn's delta -- four of the ten command
bumps on the reference turn are exactly this, and one of the four is the
human's;
* an AI fleet order costs three where the interface's costs two, because the
AI's bridge issues the fleet-task command twice, mode 0 then mode 1, and the
adder keys on (fleet, mode).
The phase spine records the one thing a literal port gets wrong: the turn submits
at phase 28 of 34, the submit latches the client closed before it builds the send
buffer, and every order the last five phases issue -- one of which is a colonize
order -- is refused. Tested through the client rather than by asserting a flag.
The task walk reproduces the two passes: rank once, walk twice, and refuse every
write in the first pass at the client rather than trusting the caller to check.
Nothing here decides anything. Which tasks exist and what each one wants are
questions about the board, and no part of this models the board; the module
supplies the order API, the pass gate and the cost function, and a caller
supplies the decisions.
game/ai tests 233 -> 423 checks; ctest 51/51 -> 53/53. Not linked into the
standalone driver, whose divergence on the reference pair is unchanged at 128.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ARBgSooAfokKUy6wKUKEyZ
|
||
|---|---|---|
| cmake | ||
| docs | ||
| include/generated | ||
| src | ||
| tests | ||
| third_party | ||
| tools | ||
| .gitignore | ||
| CMakeLists.txt | ||
| CMakePresets.json | ||
| CONTRIBUTING.md | ||
| LICENSE | ||
| README.md | ||
sots-engine
A from-scratch, functional reimplementation of the engine behind Sword of the Stars (2006). Not a byte-for-byte decompilation: behavior-equivalent code, built up one verified piece at a time (OpenRCT2-style) until the tree can build the whole application on its own.
Bring your own game. This repository contains engine code only. Game data, assets, saves, and
the original binaries are never included; tests and tools read an owner-supplied copy via
$SOTS_DATA_DIR. See CONTRIBUTING.md for the clean-room rules.
Status
Phase 2. M0 done — the shim frontend (src/shim/, a proxy binkw32.dll the original game
loads) builds, deploys, hooks, and logs from a real game launch. Engine code accrues under
src/mars/ and src/game/; each module is oracle-verified against the owner's game data before merge:
mars/parse— brace-block +.effectreaders (1,531/1,531 files agree with the reference)mars/text— flat key/value tables, id manifests, CSV (64/64 files agree)game/sim— strategic formulas (economy, research, colonies, movement) as pure functions; 356 hand-computed checksmars/vfs—.gob(ZIP) archive reader + loose-file override; entry counts and bytes verified againstunzipmars/stream— the game's self-describing save/serialization format (reader, writer, typed shapes) + gzip; three real saves round-trip byte-identicalmars/rng— MT19937 with save-state load/store; layout confirmed against real saves, draw mappings read off the binary (docs/mars-rng.md)game/data— typed catalogs (weapons, ship sections, turrets, id registries, tech tree, strings) with cross-reference checks; 229k values agree with the referencegame/design— ship-design assembly/fit/tech-gating rules and derived stats; validates all 127 stock designs from real savesapp— the standalone:sots_turnloads a save, runs one strategic turn over the published phase order of all three turn drivers, and writes a save. 14 of the 44 turn-driver phases are modelled; every phase that is not appears in the run log as a named no-op. How far it is from the byte-match, and what stands in the way, is indocs/S-standalone.md
Build: cmake --preset host && cmake --build --preset host && ctest --preset host (Linux);
tools/sync-build.sh cross-builds the shim on the lab box and stages it for deployment.
Layout (grows with the work)
src/shim/— binkw32 proxy + hooks + old-vs-new compare harness (frontend #1)src/mars/,src/game/— the engine and game reimplementation (accruing)src/app/— the standalone turn driver (frontend #2): load a save, run a turn, write a saveinclude/generated/sots_addresses.h— binary facts (RVAs/prototypes), generated from the RE repotests/— host tests; real-data tests skip unless$SOTS_DATA_DIRis settools/— build (MinGW i686 cross) and deploy scripts
Planning, findings, and verification evidence are tracked in the private RE repo (sots-re).