d1b03e5f8c
The localised string tables are decoded. language\*_local_string.tbl uses a
third archive prefix, language\, and is not IDXD: the magic is IXUD and the
strings are UTF-16 big-endian, which is why earlier ASCII-oriented dumps of
these files produced garbage.
That makes Stage 02's nine sub-objectives readable in words -- rescue the ally
destroyer, destroy all enemy fighters, sink all enemy warships, rescue the
Amalthea, keep the Caliban undamaged, sink the destroyer targeting the
Acropolis, destroy all enemy cruise missiles. Ninety-one objectives are defined
across the game.
The guide script then confirms the phase structure twice over. It reads as three
acts -- marked attackers and protecting the Acropolis, then a warship whose
engine, weapons and shield projector must be destroyed, then cruise missiles
taken down one by one -- and each act matches the per-phase roster composition
found independently. Phase 3 fields exactly nine UN_e201_ADAN_ISCMissile against
SUBOBJ_013's "You destroyed all enemy cruise missiles", an exact match between
two files decoded on different days by different routes.
And it gives a mundane explanation for every null result in the arrival work.
The phase-1 objective is stated outright in the script: the attackers with the
orange markers are the targets, meaning UN_e010_ADAN_Attacker_S, of which phase
1 fields four squadrons. Every loss line in every run log reads
UN_e007_ADAN_Turret, with e010 appearing twice in total, because SYLPH_HUNT was
built to make turrets targets and SYLPH_KEEPOUT was tuned for them. The 42 kills
were overwhelmingly the wrong 42.
Kept at 🟡 because the objective text is certain but the inference that this
particular objective gates the phase advance comes from the script's structure
rather than from measurement. The test is a pilot that prioritises e010 over
e007, which is a target-preference knob rather than new decoding, with the
existing probe watching deployed jump from 41 toward the phase-2 roster.
Reverse-engineering knowledge base
This directory is the spec-side of the clean-room: it records what the original Project Sylpheed binary does (behaviour) and how its data is laid out, so that the Rust port can be implemented from these specs without re-deriving anything and without ever copying original code.
It exists to answer one question fast: "do we already know how X works, and how sure are we?"
The one rule that matters
Never document a claim more confidently than the evidence supports, and never paste original code here.
A wrong-but-confident note is worse than no note: someone builds on it and the bug hides for weeks. Every entry therefore carries an explicit confidence and its evidence. This mirrors the project method — measure the oracle, never infer; refute before believing.
Clean-room firewall
- ✅ Allowed: behaviour descriptions, field offsets/types, formulas, state machines,
observed input→output pairs, and references to the original by address
(
sub_821B68C0) or toxenia-rs/sylpheed.db. - ❌ Forbidden here and in
crates/: pasted decompiled C/C++ or verbatim disassembled function bodies presented as the thing to reimplement. Cite the address; describe the behaviour in your own words. Disassembly is a tool for understanding, not a source to copy.
Confidence levels
| Level | Meaning | Bar to reach it |
|---|---|---|
CONFIRMED |
Behaviour verified against ground truth. | ≥2 independent observations or one observation cross-checked against an oracle (canary framebuffer, a known-correct value, a second code path). |
PROBABLE |
Strong single-source inference. | One clean observation, or an unambiguous static read of the disassembly. |
HYPOTHESIS |
Educated guess, not yet tested. | Anything else. Must say what would confirm/refute it. |
Promotion requires new evidence, not re-reading the old evidence. A HYPOTHESIS that
"looks right again" is still a HYPOTHESIS. Only an independent check promotes it.
If evidence later contradicts an entry, demote it and record the contradiction — do
not silently edit the conclusion.
When to document
- Right after a function/structure crosses from
HYPOTHESISto at leastPROBABLE— before moving to the next code path, so the knowledge isn't lost or re-derived. - Whenever confidence changes (up or down) — append to the Evidence log, don't overwrite.
- Not while it's still a pure guess with no evidence — a one-liner in the relevant backlog/plan is enough until there's something to stand on.
What to document
- Functions/code paths →
docs/re/functions/<name>.md(one file per function or tight cluster). - Data structures / formats →
docs/re/structures/<name>.md. - Keep the index in
INDEX.md(one line each: name · confidence · one-line summary).
Use the templates: _TEMPLATE.function.md,
_TEMPLATE.structure.md.
How we find and confirm code paths (the toolchain)
Everything joins on the guest virtual address (PC) — code addresses are fixed by the XEX load, identical across our emulator and canary.
- Static (cheap, try first):
xenia-rs/sylpheed.db(DuckDB: 25 481 functions, xrefs, strings, vtables, imports). Query withxenia-rs/zq.py—zq.py grep <str>,zq.py xref <addr>,zq.py dis <lo> <hi>,zq.py fn <pc>. Entry points are usually a string (zq.py grep MSG_DEMO) or an import (movie/XMA API) xref'd back to the loader. - Dynamic (when static is ambiguous): run
xenia-rswith its probe suite —--pc-probe/--audit-pc-probe-hex(fires at block entry),--mem-watch(mid-block reads/writes of a VA),--lr-trace(call/return chains),--trace-instructions,--dump-addr(read guest memory). These already exist; prefer them over hacking canary. - Oracle (correctness ground truth): canary — the Wine cross-build
xenia-canary/build-cross/bin/Windows/Debug/xenia_canary.exe(the native Linux ELF crashes / does not run — do not use it). This is the only emulator that reaches the in-game menu; ourxenia-rsnever got past the intro video. Use canary to observe output (capture its framebuffer for texture colours), not usually to instrument code — though itsbuild-crosstoolchain does compile, so small C++ probes + rebuild are possible when needed. Run muted, one emulator process at a time, point it at the real ISO (not the symlink).
⚠️ VA-equality caveat: join code by PC (fixed), but never assume a data VA holds the same bytes across emulators — allocators differ. Compare data by content/layout.