Files
Sylpheed/tools/re-capture
sylph-decoder a9755170ee formats: a keyframe's time comes before its pose, and none of them was missing
The placement region is `frames` records of `{u32 time; 36-byte pose}` after an
8-byte header, so the time word PRECEDES the pose it belongs to. Our parser's
40-byte window opened at the pose, four bytes into the record, and then read the
word at its `+36` as that pose's time -- which is the NEXT pose's. Every pose
field was right; only the time association slipped by one.

Two things the corpus has carried for weeks are that off-by-one and nothing
else: "a group's data stops 4 bytes short of its final block's time slot", and
"the last keyframe carries no time". The group is not short (8 + frames*40 is
exact) and no time is missing -- the first pose's time is the lead-in word at
`header + 8` that `parse_placements` skipped without asking what it was.

Disc-wide, 33 archives, 13 991 groups, each test with a control:

  A  lead-in prepended to the shifted times is non-decreasing  13991/13991
  B  a non-zero lead-in is strictly below the next time         5058/5058
     control (another group's lead-in, same bundle)            70.9%
  C  multi-segment alpha ramp at a constant rate, corrected    857/1540
     the same, under the old reading                             0/1042

C is the one that cannot be argued with: interpolation between keyframes is
linear, and under the old reading not one multi-keyframe ramp on the disc comes
out at a constant rate.

Adoption is free on every static composite, which is what the corpus previously
declined it over. `SYLPHEED_KF_TIME_SHIFT=1` moved GP_TITLE build 7 by 13.1% of
its pixels because it left pose 0 untimed; with the lead-in restored, all 12
GP_TITLE builds render byte-identically, and across 217 builds in six archives
only two elements pick a different rest pose -- both times between two poses
that are equally invisible.

`SYLPHEED_KF_TIME_SHIFT` is gone; `SYLPHEED_KF_TIME_LEGACY=1` restores the old
reading for A/B work.

ui_header_time_disc needed one line: 546 bundles whose every group is a single
static pose now report max_time = 0 where they previously reported no time at
all. Excluding them, the result it guards strengthened -- the bound holds over
2 859 bundles instead of 2 313, still with zero violations.

Not established: the executable's own parser. Reach is written down.

docs/re/ui-keyframe-record-layout.md

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Nsxw1A9JseUw99Yw1ZRQzY
2026-08-29 14:01:39 +00:00
..

Runtime-capture harness (sylph-re container)

Screenshot-driven scripts for reading the running retail game's menus under Xenia Canary + lavapipe, headless. They assume the container helpers screenshot, vgamepad, pad are on $PATH and HOME=/sylph-home/re.

Script What it does
skip_intro.sh Boot → main menu, unattended. Taps A only while the intro movie is actually playing (frame-to-frame RMSE), then once at the PRESS Ⓐ BUTTON title. Static logo screens are left alone, so a stray tap can never land on NEW GAME.
wait_title.sh Older variant: wait for the title (green Ⓐ glyph at px 625,618) and tap A. Superseded by skip_intro.sh.
step.sh One Arsenal navigation step (down/up/next/prev/none) + a compact capture: weapon list stacked over the DATA SHEET.
sweep.sh Walk a whole weapon-type list, capturing only rows that show a DATA SHEET — locked rows (a "Conditions to Develop" panel) are detected by the brightness of the Range Class label box and skipped.
type.sh Change weapon-type tab N times (RB) and report the header strip.
hp.sh / cyc.sh Hangar hard-point carousel: cyc.sh steps it (d-pad down, not left/right) and captures the Name + DATA SHEET.

Input timing under lavapipe: the game polls input at its own low frame rate, so a 60 ms d-pad tap is dropped roughly half the time. 200 ms is reliable; 300 ms starts to auto-repeat (two rows per press).

Findings produced with these: docs/re/weapon-datasheet-runtime.md.

Guest-memory tools (no screenshots)

Script What it does
gmem.py Read the live guest address space out of /dev/shm/xenia_memory_* (Xenia's backing file), addressed by guest VA. find / read / words.
weapon_runtime.py Solve the Weapon/Shell struct layouts against the disc records and read the fields the disc defaults.
unit_discover.py Find which runtime class carries a set of ID strings, assuming no vtable: tallies the word at pointer_site - k across distinct IDs.
unit_runtime.py Same solver for the unit\UN_*.tbl definition objects (vtable 0x820af844). Unions several snapshots — unit definitions are per-stage.
schema_order.py Merge a sub-record's field-declaration order across all tables (topological sort); the layout check that pins fields no table ever values.
order_check.py Test offset = base + 4*index for one table's sub-record against solver output.
grab_tutorial.sh Cold-boot Canary, walk to the Nth TUTORIAL entry, wait for the stage load, snapshot guest RAM. One emulator per capture — backing out of a loaded mission wedges it.

Snapshot first — cp --sparse=always /dev/shm/xenia_memory_* snap.bin (~2 s) — and point $GMEM_FILE at the copy; the running emulator pegs every core under lavapipe.

🔴 pgrep -f / pkill -f match YOUR OWN shell

An agent driving this toolkit runs its commands through a wrapper shell whose command line contains the pattern being searched for. So

pgrep -f 'pilot\.py'        # matches the wrapper running this very command
pkill -f 'fly_session|pilot\.py'   # kills that wrapper — the script dies mid-way

This has cost four separate mistakes in one session: two scripts killed mid-execution, and twice a "is it already running?" guard that answered yes because it had found itself. The [p]ilot bracket trick does not help when the literal invocation (python3 pilot.py …) also appears on the wrapper's command line.

What works:

pgrep -x xenia_canary                       # exact NAME match, no -f
ps -eo pid,args | grep 'python3 pilot.py' | grep -v snapshot-bash
kill -9 <explicit pid>                      # look it up first, then kill by pid

The snapshot-bash filter is the reliable tell: the wrapper's command line always contains the shell-snapshot path.

🔴 The emulator does not survive the end of an agent turn

/work/.claude/settings.json defines a Stop hook that kill -9s every xenia_canary when a turn ends, printing "Stop hook killed N stale xenia process(es)".

So:

  • never launch a run intending to read it in a later turn — it will be dead;
  • an experiment has to produce its evidence within the turn that starts it;
  • prefer measurements that land in the first minutes of flight. REMAINING OB steps 4 → 8 → 12 inside the first few minutes, which is why a two-pass differential works in one turn while a 25-minute freeze watch does not.

This cost three iterations of investigating a "mysterious external SIGKILL", complete with cgroup and host memory forensics, before the hook was found. When a process dies at a session boundary, check the harness first.