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.
Find a file
lane-b6 0fcbb69ba5 game/sim + app: ship construction -- the build-queue completion bookkeeping, and S11's sub-pass wired in
game/sim/construction.{h,cpp}: Game::ShipRecords (four per-hull-class arrays plus the
per-design vector, sized by ENUMERATION against the wire, not by what the code touches)
and the completion bookkeeping BuildQueue::ProcessTurn performs -- the per-class built
counter, whose indexed increment has EXACTLY ONE writer in the whole image, and the
find-or-append per-design record keyed by the design's object id. RunSystemConstruction
wraps the point pass and keeps each completion's design id, which the point pass alone
does not report.

game/sim/colony: corrected from the instruction stream -- with points <= 0 the entry test
branches to the epilogue, so the REMOVAL SWEEP IS SKIPPED TOO. Carried as a labelled
hypothesis: no corpus save can reach the state that shows it.

app/construction_phase.{h,cpp}: S11's build-queue sub-pass, reported on its own line
because what blocks it is not what blocks the rest of the colony turn. It is blocked on
the per-system output term for points; it is NOT what the archived ship census waits on.

tests/game_sim/test_construction.cpp: 65 checks, including a corpus oracle the campaign
already owned and had not noticed -- zuul-turn16-noderoute -> zuul-turn17-rollpending is a
real consecutive-turn pair in which six orders complete and one is partially advanced.
The test SOLVES for the point total rather than assuming it, so a non-FIFO order, a
per-order budget or skip-instead-of-stop each falsify it.
2026-09-08 14:39:20 -04:00
cmake m0: binkw32 proxy shim, minhook, trace hook on Application::Initialize; build/deploy tooling 2026-09-07 17:22:15 -04:00
docs docs: B6 prediction before the build -- the build queue closes nothing on either reference pair 2026-09-08 14:33:16 -04:00
include/generated merge lane E1: income chain 25/25 on the BnkEl oracle; difficulty multiplier resolved (turn.cpp union-resolved: tail phases 17, 21, 31) 2026-09-08 13:55:49 -04:00
src game/sim + app: ship construction -- the build-queue completion bookkeeping, and S11's sub-pass wired in 2026-09-08 14:39:20 -04:00
tests game/sim + app: ship construction -- the build-queue completion bookkeeping, and S11's sub-pass wired in 2026-09-08 14:39:20 -04:00
third_party mars/vfs: gob ZIP reader + native override, miniz 3.1.2; oracle-verified 8352+2035 entries 2026-09-07 17:40:51 -04:00
tools b4: colony + movement hooks; 22 formula corrections (growth curve has no capacity term, range margin +0.05f, ties-to-even rounding); 3 verified signatures 2026-09-08 00:57:55 -04:00
.gitignore init commit 2026-09-07 17:07:54 -04:00
CMakeLists.txt lane P2: fleet path planning (game/nav) 2026-09-08 12:43:11 -04:00
CMakePresets.json m0: binkw32 proxy shim, minhook, trace hook on Application::Initialize; build/deploy tooling 2026-09-07 17:22:15 -04:00
CONTRIBUTING.md CONTRIBUTING: note uv tool install cmake as the local workaround 2026-09-08 09:07:47 -04:00
LICENSE init commit 2026-09-07 17:07:54 -04:00
README.md src/app: the standalone -- load a save, run a turn, write a save 2026-09-08 10:35:45 -04:00

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 + .effect readers (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 checks
  • mars/vfs — .gob (ZIP) archive reader + loose-file override; entry counts and bytes verified against unzip
  • mars/stream — the game's self-describing save/serialization format (reader, writer, typed shapes) + gzip; three real saves round-trip byte-identical
  • mars/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 reference
  • game/design — ship-design assembly/fit/tech-gating rules and derived stats; validates all 127 stock designs from real saves
  • app — the standalone: sots_turn loads 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 in docs/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 save
  • include/generated/sots_addresses.h — binary facts (RVAs/prototypes), generated from the RE repo
  • tests/ — host tests; real-data tests skip unless $SOTS_DATA_DIR is set
  • tools/ — build (MinGW i686 cross) and deploy scripts

Planning, findings, and verification evidence are tracked in the private RE repo (sots-re).