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
alex fa53e02b53 L1: probe the AI client seed across two processes -- it is fresh every time
Two hooks, Mars::RNG::Seed 0x0049fdf0 and StrategyApp::RunAI 0x008706f0, and a
config that turns everything else off. Two launches from the same save, load
only -- the AI clients are constructed on load, so no End Turn is needed.

Result: every AI client's generator seed differs between processes (net 32,
496 and 512 all move), while the record structure is byte-for-byte the same
shape and one Seed call with seed=0 produces an identical state in both runs.
So the turn1-state -> turn2 nondeterminism is a SEED effect, not the ordering
effect that was predicted, and lane AI1's 'every draw from the static generator
returns 0' is falsified by measurement.

The prediction said the opposite and is left in docs/L1-predictions.md with its
outcome underneath.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ARBgSooAfokKUy6wKUKEyZ
2026-09-08 18:22:14 -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 L1: probe the AI client seed across two processes -- it is fresh every time 2026-09-08 18:22:14 -04:00
include/generated L1: hook BeginProcessTurn and the three script-object writers a turn reaches 2026-09-08 17:43:10 -04:00
src L1: probe the AI client seed across two processes -- it is fresh every time 2026-09-08 18:22:14 -04:00
tests merge lane SV: script-object event bus (CMake lists merged into their constructs, rule 22) 2026-09-08 16:48:49 -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 merge lane W2: watchpoints + multiplayer Tier 0 (CMake list and main.cpp union-resolved to keep both instruments; header regenerated) 2026-09-08 15:28:28 -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).