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 a7348be72c game/events: the player event log and the five research events
Recovers the game's event-posting API so the engine can post events and the
compare harness can see them. Until now the owner's event list was invisible to
every layer: B3's replace-mode oracle failed by exactly one item across 40,300
(an unposted EVENT_RESEARCH_OVERBUDGET) while its compare read clean, and B2's
clean compare bounds the economy fields only.

New pure module src/game/events:
  * EventStorage / TurnEvents / PlayerEvent -- the list is bucketed by TURN, not
    flat, which the save-editor struct notes had wrong.
  * EventStorage::Post reproducing the original's rules, including the four that
    change save bytes: the FLT_MAX (not infinity) default position; action 0 with
    no subject and no position storing as 2; per-bucket dedup that compares
    message/image/location/position/action but NOT summary; and EvNxID starting
    at 0 and being promoted to 1 on the first post.
  * PruneOldTurns reproduced with its off-by-one: of a leading run of buckets
    older than turn-50 it erases n-1, so one stale bucket always survives. The
    survivor is serialized, so correcting it would diverge.
  * research_events: the five events the research path raises, their EvImg
    identifiers and string-table keys, and the 0.8 completion split evaluated
    against (double)0.8f rather than the decimal 0.8.

Localized text is deliberately absent: only the EVENTSUM_/EVENTMSG_ keys are
here and the text resolves through a caller-supplied lookup, as the game does.

The four event offsets the B3 hook carried as local literals now come from the
generated header; they are read off instructions rather than inferred from the
save schema.

tests/game_events: 112 checks including a replay of the event list
turn3-state.sav actually holds. ctest 31/31 -> 32/32.

docs/E-events.md carries the proposed region and Coverage wording for the next
B3 recapture.
2026-09-08 02:45:57 -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 game/events: the player event log and the five research events 2026-09-08 02:45:57 -04:00
include/generated game/events: the player event log and the five research events 2026-09-08 02:45:57 -04:00
src game/events: the player event log and the five research events 2026-09-08 02:45:57 -04:00
tests game/events: the player event log and the five research events 2026-09-08 02:45:57 -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 game/events: the player event log and the five research events 2026-09-08 02:45:57 -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 init commit 2026-09-07 17:07:54 -04:00
LICENSE init commit 2026-09-07 17:07:54 -04:00
README.md b3: research hook + RNG-snapshot compare design; fix draw mapping to y/(2^32-1), NextInt inclusive, float32 odds, spend floor, decay constants 2026-09-07 23:14:08 -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

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)
  • 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).