Commit Graph

18 Commits

Author SHA1 Message Date
Josh Creek 624d1c6b78 docs(multiplayer): add a single index of outstanding work, and record the identity defect
The document had no one place that answered "what is left". Outstanding
items were spread across two phase-gate lines, two phase tables, §11, and
prose buried in the phase notes - and the name-keyed slot-reservation
hijack, which an adversarial review demonstrated with a real three-process
run, was not written down anywhere at all. It existed only in a
conversation.

New §0 indexes everything not done, in four groups: verification a
machine cannot do (the Phase 4 playtest, the Phase 5 3v3 gate), known
defects left unfixed with their severity, the one open architectural
question, and the two unstarted phases. Each row points at the detailed
write-up rather than duplicating it, and the phase gates now point back.

§11 gains the identity defect in full: reservations match on
slot.player_name and nothing else, with no uniqueness constraint on names
anywhere, so a peer joining during the 30s window with a departed
player's name is handed their slot, ship and team. A bespoke token would
be half of task 7.4 thrown away, so it stays deferred - with the
consequence stated plainly rather than implied, and listed as a
precondition of Phase 6's internet-facing gate.

Also refreshes the stale status paragraph and task 5.10 for the replay
log's reject recording, write-failure handling, close(), and dump tool.
2026-08-21 16:51:52 +01:00
Josh Creek ff725e1ffa feat(multiplayer): §6.3 late joiners take a vacated slot at the next kickoff
"Spectate now, take the slot at the next kickoff" was a print statement.
The server logged it and never acted; on the client, _is_spectator was
assigned once in _on_match_config_received and never revisited - and that
handler returns early whenever _slots is non-empty, so no rebroadcast
could promote an in-match spectator. The reconnect path only worked
because a returning player is a fresh process.

Server: late joiners are queued in arrival order and the queue is drained
from _begin_kickoff, before the reset transforms are read, so a promoted
player's ship is placed by that same kickoff and the controller swap
lands on an already-frozen body. A slot is available only once its player
has gone AND their 30s reservation has lapsed - §6.4 outranks §6.3, since
taking a reserved slot would quietly break the reconnect promise.
_abort_if_abandoned now counts a waiting spectator as somebody present,
or the one person queued for the slot that just opened is dumped to the
lobby at the moment they were about to get it.

Client: new broadcast slot_assigned (reliable, channel 0). Broadcast
because every client holds its own slot list and one naming the wrong
peer keeps flying somebody else's ship as a remote body; reliable because
no per-snapshot field would re-converge a client that missed it. The
promoted client undoes what made the body remote - fresh interpolator,
physics interpolation back on, offsets cleared - and deliberately does
not unfreeze, clearing _local_prediction_ready so the next snapshot
teleports it to a real authoritative pose first. The controller-attach
block moved to _take_local_ownership rather than being copied.

New --role=host-latejoin/--role=client-latejoin and
--slot-reservation-seconds=. Verified 4/4 both sides: queued, NOT
promoted merely because the reservation lapsed, takes the slot at the
kickoff, same ship instance, and both peers independently measure ~45.7m
under its input. Control with a 90s reservation: kickoff fires, nothing
is promoted, the slot still reads the departed player's name.
2026-08-21 16:47:35 +01:00
Josh Creek 5714829c13 test(multiplayer): grade §6.4's reconnect from the returning player's side
The disconnect scenario only ever asserted the server's bookkeeping, and
the client's half was failing every run. run_disconnect_host_check ticked
60 physics frames past the reclaim and then shut the server down, so the
reconnecting client - whose wiring check waits a 2.0s settle before it
looks at anything - had its peer torn out from under it and reported
"current_scene is not NetworkedMatch after 2.0s". The host printed PASS
throughout, and the host was the side anyone read.

The hold is now a real window (8s), and the host also asserts that the
reconnected player's input reaches the server and moves the ship the
server owns - every other assertion there is slot bookkeeping that would
hold identically for a client whose input pipeline came back dead. Both
position and connection state are sampled while the peer is still
connected: the client leaves on its own schedule, and an end-of-hold
sample reported still_connected=false for a good run.

New --role=client-reconnect asserts the returning player is not a
spectator, owns a slot with its own peer_id, has a real ship, rejoined a
live match with the clock already known (§6.2 step 2's bootstrap), and
can still drive. That set is chosen because a stale _last_match_config
once made a reconnecting player a spectator, and that bug was visible in
this scenario's own logs while it reported PASS.

Verified 3/3 both sides. Control: rejoining while the slot is still
occupied fails on is_player=false - and since the first control run
reported it as the generic "lost its ship mid-drive", the spectator case
is now diagnosed before the drive rather than after.
2026-08-21 16:25:25 +01:00
Josh Creek 866efa0d9b fix(multiplayer): server no longer rate-limits a backlog it caused itself
Closes task 5.10's three recording gaps, and the gap-closing found a real
input-loss bug.

Replay log: a failed write now ends the log permanently instead of
desyncing every later record's framing; close() is called from _exit_tree
with a summary, since the RefCounted destructor closes it implicitly but
never says whether the log is complete; rejected packets are recorded
with their reason in the kind byte (framing unchanged, FORMAT_VERSION 2
so "no rejects" differs from "this build never recorded them"). Recording
is capped at 8 per peer per window - uncapped, the diagnostic is a remote
disk-fill amplifier, since the attacker picks the packet rate. Uncapped
totals live on MatchSim and survive the peer's disconnect.

The bug: a 2s host stall has the client sending at 60Hz throughout, and
ENet delivers that whole backlog in the first window after resume - 70 of
an honest client's packets rejected as "rate limit exceeded". Redundancy
does not cover it, because the dropped packets are contiguous: 0 of 70
rescued, and 82 of 923 sequences (8.88%, ~1.4s of input) never reached
the server, against 0.00% with no stall. Every prediction gate passed.

Fixed by granting each already-tracked peer a capped, two-window packet
grace when the server detects its own wall-clock stall. Rate-limit
rejects 70 -> 0, sequences missing 8.88% -> 0.00%, seq-guard rejects
9 -> 0. Controls on the unfixed build lost 4.34/7.52/7.86%. All three
abuse roles still disconnect and no flood induced a stall, so the grace
cannot be farmed.

Also corrects an earlier wrong conclusion: the reviewer's free-flight
p95 0.688 is real and reproduces on two processes with 0.0% snapshot
loss. The plain --role=client drive fails the 0.5 free-flight bound in
3 of 8 runs because that drive is mostly a contact test - the harness
comment already said so - leaving a cohort as small as 12 samples.
Near-surface error is genuinely several times open-air error, so the
calibrated bound now belongs to --exercise-free-flight alone and the
plain role asserts the always-well-sampled all-cohort percentiles at
1.2/2.0, printing the free-flight numbers as reported-not-asserted.
6/6 plain runs pass where 3/7 failed; tightening to 0.3 still fails.

tools/replay_dump.gd reads a log back: counts by kind, plus how much of
the input sequence stream reached the server once redundancy is counted.
2026-08-21 16:10:43 +01:00
Josh Creek e51dc765a2 test(multiplayer): report transport health on prediction-quality failures
A percentile alone cannot tell "the predictor regressed" from "the client
never received the data". The client gate now prints snapshot_loss /
snapshot_age / rtt on every run, and on a quality failure with >20% loss
says explicitly that the run was transport-starved. It deliberately does
not convert the failure into a pass: a client that cannot receive
snapshots is still a failed run, just a differently-diagnosed one.

Both directions of the new branch verified non-vacuously (forced true so
it fires and formats; restored so it stays quiet on a healthy run while
the INFO line still prints).

Records the investigation behind it in multiplayer-todo.md: the reviewer's
3-process p95 0.688 did not reproduce. An idle third process costs nothing
(p99 0.094), a spectator costs a small but real amount (p99 0.094-0.146),
and snapshot loss held at 0.0% even under 2x CPU oversubscription - all an
order of magnitude inside the 0.5/2.0 gates. Also notes that a previously
working class_name can silently drop out of the .godot class cache, which
surfaces as a bogus parse error with nothing in git status to explain it.
2026-08-21 15:24:58 +01:00
Josh Creek a5cbc977b5 feat(multiplayer): Phase 5 tasks 5.6-5.10 - disconnects, spectators, replay log
Completes Phase 5's implementation. Every task is verified at 1v1; the
3v3 phase gate itself has not been run and remains outstanding.

5.6/5.7 disconnects: a ship is never despawned. The slot keeps it and
swaps the controller (--fill-bots gives it a bot, the default leaves it
inert per §1.4), sets `stalled` immediately so the nameplate greys out
rather than waiting ~500ms for the abandoned jitter buffer to starve,
and reserves the slot for 30s keyed by player name so a reconnect gets
the same ship back.

5.7 was a real bug, found by the test rather than by review:
SlotInfo.controller was declared RLShipController, but the takeover
swaps in an AIShipController or the base controller - the narrower type
makes that assignment fail its type check, leaving the field pointing at
the controller set_controller() just queue_free()d. It surfaced as
controller_valid=false on the first run. The per-tick action write is
now also gated on `is RLShipController`, since a disconnected slot's bot
drives itself and overwriting it from a starving buffer would pin it to
the departed player's last input.

§6.4's two rules conflict: reserve for 30s, but abort when the last
human leaves. Applied naively the abort wins instantly in a 1v1 and the
reservation can never be redeemed, making reconnect unreachable exactly
when it matters. Abort now waits for no connections AND no outstanding
reservations.

5.8 spectators: a slotless peer spawns no ship and receives the same
snapshot broadcast. HUDController.spectator_mode keeps the clock, score
and goal celebration and hides only the ship instrument cluster - it
previously push_error'd and bailed, leaving a spectator with a dead HUD.
Camera cycles ships in slot order then the ball. --max-spectators caps
it, counted from the live peer list so a dropped spectator cannot leak a
unit of the cap.

5.9 escape respawn: new GameMode._on_bodies_respawned() virtual;
NetworkedMatch bumps reset_gen through Phase 2's deferred path so the
bump and the respawned pose land in the same broadcast. Single-player
modes are unaffected - the base is a no-op.

5.10 replay log: scripts/replay_log.gd, --replay-log=<path>, storing the
wire bytes verbatim in both directions rather than re-serialising - a
re-encode would launder away precisely the malformed payload being
chased. A live 6s match recorded 1115 records (557 inputs / 558
snapshots) and a stored snapshot decodes back to server_tick=100
match_state=WARMUP bodies=2.

Note for future work: --check-only --script is the only thing that
catches a parse error in networked_match.gd, because the unit runner
never loads it. Two separate breakages passed the full unit suite while
breaking every two-process run. A new class_name also needs --import
before it resolves.

Test surface: --role=host-disconnect (three-process 5.6/5.7 scenario),
--match-length=<s>, --replay-log, --fill-bots/--no-fill-bots,
--max-spectators. The ball-contact scenario now steers at the ball with
closed-loop real input instead of a hand-tuned fixed heading, which 5.3
broke by adding KICKOFF_YAW_JITTER; thrusting while turning took it from
2/3 to 5/5.

Regression: 87 unit tests; free-flight LAN p99 0.094m with 0 hard snaps;
transition gate 0.00%; ball contact 5/5; lifecycle goal cycle and full
match to RESULTS/LOBBY; disconnect+reconnect; two-bot CI.
2026-08-21 10:25:15 +01:00
Josh Creek 3d6906b981 feat(multiplayer): Phase 5 tasks 5.2-5.5 - clock, kickoff, goals, full time
Implements the rest of the §6.2 lifecycle on top of 5.1's state machine.

5.3 kickoff: the server resets every body and broadcasts the RESULTING
transforms, never a seed - §1's locked decision, because shared-seed
determinism needs both sides to consume the RNG stream in identical
order forever and the first randf() added to the reset path desyncs
silently. Countdown is derived from server_tick on both peers, and a
kickoff that lands after its own resume tick applies immediately and
skips the countdown rather than scheduling into the past.

5.4 goals: goal_scored(scoring_team, score, goal_tick, resume_tick).
Score is authoritative at sensor time, before any presentation. The
reset moved OUT of the sensor path and into the kickoff at resume_tick,
which is what stops the server resetting while clients are still
mid-celebration. Engine.time_scale is never touched.

5.2 clock: tick-derived, no Timer and no _process polling. The goal
pause shifts the absolute end_tick by (resume_tick - goal_tick) rather
than pausing anything, so no float drift accumulates across goals.

5.5 full time: clock expiry -> FULL_TIME -> sudden death on a draw or
RESULTS, golden goal in overtime, then LOBBY on both peers - clients
return to the lobby, not the main menu. get_tree().paused is never used.

Four bugs found and fixed while building this, each by a failing run
rather than by inspection:

- Tick order was load-bearing: _update_kickoff_countdown() clears the
  same _kickoff_resume_tick that _update_match_state() reads to leave
  WARMUP, so running the countdown first wiped the transition condition
  and the match sat frozen in WARMUP forever.
- _apply_match_state resets _state_deadline_tick on every transition, so
  a GOAL_PAUSE deadline assigned before _set_match_state was wiped and
  the match never resumed. Deadlines are now owned by _apply_match_state.
- Freezing "all bodies" is wrong on a client. Remote ships and the ball
  are permanently FREEZE_MODE_KINEMATIC and transform-driven; freezing
  them all unfroze the remote ones on the way back out, so they fell
  under gravity while the interpolator fought them - 210 hard snaps and
  an infinite p99. A client now freezes only the one body it simulates.
- A frozen body never runs _integrate_forces, so the queued kickoff
  teleport was stranded by an immediate set_deferred("freeze", true).
  Freeze now happens on a strictly later tick, the same pattern Phase 2
  used for _pending_reset_gen_bump_tick.

Prediction and reconciliation are suspended while the match is not live:
during a countdown or goal pause the local ship is frozen on both peers,
and running delta transport over those frozen states produced a p95
position error of 2.4e10 m. Input keeps flowing so the server's jitter
buffer does not starve into `stalled`.

Also fixed: a kickoff can arrive before match_config, and body order is
slot order - applying it early placed the BALL at positions[0], on top
of the first ship, which the ball-cam reported as "target vector can't
be zero" 95 times. It is now held until the roster exists.

Test changes: the ball-contact scenario steered by a hand-tuned fixed
heading, which 5.3 broke because kickoff applies KICKOFF_YAW_JITTER - it
flew past the ball in 3/3 runs. It now closes the loop on the actual
bearing using real input actions. Assertions that read a frozen ship
(freeze, thrust) are gated on the match being live, and the hooks now
survive the scene teardown at RESULTS instead of hanging on freed
objects for the full timeout.

Regression: 81 unit tests; free-flight LAN p99 0.143m and 80±20ms, both
0 hard snaps; transition gate 0.00%; ball contact 3/3; two-bot CI.
2026-08-21 10:01:39 +01:00
Josh Creek 9f28c02488 feat(multiplayer): Phase 5 task 5.1 - match lifecycle state machine
Adds the §6.1 state machine, its broadcast, and the client side that
follows it. Physics, freezing and input are deliberately NOT gated on
state yet - 5.3 and 5.4 own freeze/unfreeze at kickoff and goal, and
doing it here would change the conditions every Phase 4 prediction gate
was measured under.

scripts/match_state.gd holds the enum and transition table as pure data
with no scene or RPC dependency, so the table is checked exhaustively
rather than by example: every state reachable, every state has an exit,
no self-transitions, abort-to-LOBBY from anywhere per §6.4, illegal
shortcuts rejected, unknown values refused rather than coerced. The enum
values are the wire format - match_state has been a u8 in the snapshot
header since §2.4 - so a test pins them; only append, never renumber.

The server validates every transition and push_errors an illegal one
rather than following it. Clients deliberately do NOT enforce the table:
authoritative state must be accepted, and a late joiner legitimately
jumps straight to PLAYING.

Two channels carry the state. state_change (reliable, channel 0) is
prompt and carries an absolute at_tick, never a duration. The snapshot's
match_state byte is the catch-up path for a client not yet sent a
transition - a late joiner, or the window between scene load and the
first RPC.

The byte needs a tick guard, and this was found the hard way. Snapshots
are unreliable_ordered on channel 2 and ordering holds only within a
channel, so a state_change for tick N routinely arrives before an
in-flight snapshot from tick N-2. Without the guard the client applies
the new state then gets dragged back by the older byte, oscillating on
every transition - observed directly as LOADING -> WARMUP -> LOBBY ->
PLAYING -> LOBBY while running a deliberately-broken-byte control. Only
a byte at least as new as match_state_since_tick is accepted.

WARMUP_TICKS/GOAL_PAUSE_TICKS are honest placeholders so 5.1 drives real
transitions to verify against; 5.3 and 5.4 replace them. The server also
leaves LOADING immediately rather than waiting for scene_ready, which
does not exist yet.

New smoke flag --exercise-match-state, passed to both roles: the host
forces a goal to drive a GOAL_PAUSE cycle, the client records the
sequence and asserts every consecutive pair is legal, that ticks are
monotonic, and that the wire byte agrees with its own state. Observed
LOADING -> WARMUP -> PLAYING -> GOAL_PAUSE -> WARMUP with tick deltas
matching the configured durations exactly.

Verified against a control: hardcoding the snapshot byte back to 0 fails
both the byte assertion and the transition-legality assertion. The byte
is asserted separately from the RPC precisely because everything else in
the check is RPC-driven and would pass with a dead byte - the same gap
that hid the Phase 4 label bug (gotcha 47).

Regression: 81 unit tests; 60s free-flight LAN (p99 0.148m, 0 hard
snaps, marker 0/3364); transition gate 0.00%; ball contact; two-bot CI.
2026-08-21 09:31:22 +01:00
Josh Creek 75f485667b feat(multiplayer): Phase 4 prediction correctness + two input-death fixes
Closes Phase 4's outstanding action-sequence-correctness invariant, then
fixes two server-side bugs an adversarial review of that work uncovered.
Server simulation, bot observations, collision resources and tick rate are
unchanged: the server_physics_parity trace is byte-for-byte identical to
HEAD across 360 ticks including both ships' full observation vectors.

4.11 - prediction history filed under the ISSUING sequence

_send_local_input filed each post-step predicted state under the timeline's
estimate of the sequence the server would consume this tick, trailing
issuance by input_lead. The body had integrated the intent issued under
_input_seq, so predicted[S] held "state after the intent from now" while
the server's authority for S is "state after action(S)". They agree only
while the stick is still. Filing under _input_seq costs nothing: which
action the ship uses is decided in LocalNetShipController.get_action() and
is untouched.

Every prior Phase 4 gate held its input steady, and a steady input cannot
falsify a sequence label - the 60s runs honestly reported marker=0/3784.
New --exercise-input-transitions role toggles thrust every 6 ticks; it is
the only gate that can catch a label regression. Verified non-vacuous: the
old label fails it at 50%.

4.12 - issued-but-unsimulated sequences, and the release path

An attack (delta > 1) issues and sends several sequences for one local
physics step. Those gap sequences had no recorded prediction, so a server
ack of one reported missing_not_recorded - indistinguishable from ring
loss, costing a teleport and resync suppression several times a minute.
They are now recorded stateless via record_unsimulated() and answered with
a new "skip" decision mode. Free-flight hard snaps: 25/8/4 -> 0/0/0.

A release (delta == 0) re-recorded at the unchanged _input_seq, filing the
current intent under a sequence that went out carrying a different action;
LocalInputTimeline deliberately refuses to mutate an issued sequence, so
the ring contradicted the wire. Recording is now skipped on release ticks.

4.13 - two Phase 3 bugs silently killing player input

(a) InputJitterBuffer.consume() advanced last_applied_seq on every tick
including a starve. Since ingest() discards seq <= last_applied_seq, one
starve on a sequence the client had not sent yet stranded the stream one
ahead of arrivals permanently - both sides advancing in lockstep, every
honest packet discarded on arrival. The client's own input_lead release is
enough to trigger it, so input died for ~30 ticks roughly every 6.5s on a
clean LAN. Now only gives up on a sequence once strictly newer data proves
it lost. Silent-client stall and ring-overflow resync are unchanged.

(b) The seq-range guard bounded incoming seq against highest_ingested_seq,
which only advances inside ingest(), which that guard gates. After a ~2s
host hitch every packet was rejected forever with no diagnostic (600+
consecutive rejections reproduced via SIGSTOP). Third iteration of this
guard; each previous version bounded against a value only the accepted
path could advance. Adds an escape after 10 consecutive rejections, which
grants an attacker nothing the rate limiter does not already bound.

(c) The transitions gate reported PASS at 3.76% while input was completely
dead, because suppression stops _record_metrics - a worse outage yields
fewer samples and a LOWER rate. Now scales the required sample count with
run length and asserts the wire's server_stalled bit. Reverting both fixes
makes it fail at samples 292/600, server_stalled=true, input_lead=12.

Fixing (a) also explained a residual the review had already traced: 151 of
151 action-marker mismatches were the server repeating a stale action on a
starve, not a prediction defect. Marker is now 0.00% in all three
conditions (was 1.7-2.5%), and free-flight p99 improved to
0.141/0.168/0.154m from 0.170/0.176/0.184m.

Two pre-existing test defects fixed alongside: the ball gate asserted
RTT-masking on a link with no RTT (flaked 2 in 5; now asserted only at
rtt >= 20ms, 5/5 under latency), and the two-bot CI compared scores across
a 3-5s window (now polls the scores the server actually held; note
score_changed is emitted only on the client path).

QA: 72 unit tests; 60s free-flight at LAN/80+-20ms/5% loss; transition
gate in all three; 2.0s and 3.5s host-freeze recovery; ball contact x5;
two-bot CI x3; all three abuse roles; net/match_net/clock/lobby smokes.

Phase 4 sign-off still pending a human playtest at ~100ms RTT - the
milestone asks how it feels, which no gate here answers.
2026-08-21 09:17:19 +01:00
Josh Creek cf73074e27 fix(multiplayer): resolve composition regression from second adversarial review
A second adversarial review of the previous fix commit found two of its
nine fixes silently defeated each other: the seq-range guard (fix for a
MEDIUM epoch-mismatch finding) capped the exact variable the ring-overflow
resync (fix for the original CRITICAL finding) depends on, making the
resync unreachable in production and recreating permanent input death at
a lower failure threshold, reachable via ordinary server tick loss alone.

- CRITICAL: rebind the seq-range guard to InputJitterBuffer's own
  highest_ingested_seq (now public) instead of the consumer-side
  last_applied_seq, so it tracks the client's send epoch rather than a
  value that can lag arbitrarily far behind during a stall.
- HIGH: InputLeadController's release logic still ANDed the old
  `lead > LEAD_MIN` gate onto the new depth-driven condition, so a
  backlog the controller never caused still couldn't drain. Split into
  two independent decisions: the seq-duplicate action follows real
  depth alone; lead's own bookkeeping separately never drops below its
  floor.
- MEDIUM: widen the CI driver's movement/stalled sampling margin
  (run_seconds - 2.0, was - 0.5) and assert the peer is still in
  multiplayer.get_peers() at sample time, since the old margin let the
  check pass on residual starvation grace after a bot had already
  disconnected.
- LOW: measure horizontal-only displacement in the human smoke test's
  movement check — the old 3D-distance bar was beatable by pure
  gravity settling with fully dead input.
- LOW: fix a real "clean stderr" violation (match_net.gd broadcasting
  a departure notice to a peer whose ENet channels are already torn
  down, including a second peer disconnecting in the same poll batch)
  by deferring the notification to the next idle frame.
- Wire the server's per-slot stalled bit into the client debug overlay
  for real — a prior commit message claimed this already reached the
  overlay when only the CI gate actually read it.

Re-verified end-to-end against the real production RPC path (not just
unit tests in isolation, which is how the composition bug got past the
first round): a 2-bot CI match with a 1.5s host SIGSTOP freeze injected
mid-run, well past the 0.6s threshold the review reproduced the bug at,
now recovers cleanly on repeated runs with zero stderr noise.
2026-08-20 18:26:12 +01:00
Josh Creek 2325313ad2 fix(multiplayer): adversarial review fixes for Phase 3
An Opus subagent's adversarial review of Phase 3 found a critical, silent,
permanent bug plus eight smaller real issues, all empirically verified
with real two- and three-process runs:

CRITICAL: InputJitterBuffer's 32-entry ring permanently bricked a
player's input once the un-consumed backlog exceeded the ring's
capacity - a fresh arrival would land in the exact slot consume() was
still waiting on, and since both counters only ever advance, the gap
never closed. Reproduced with a real SIGSTOP/SIGCONT host freeze:
client movement dropped from ~26m to 0.00m at ~0.7s, worse under real
loss (a lossy link lowered the fatal threshold to ~400ms), and
reachable via ordinary clock drift with no external trigger at all.
Fixed by tracking the highest seq ever ingested and having consume()
jump directly to what the ring can still provide once the gap exceeds
capacity, instead of starving through an unrecoverable span. Re-verified
with a 3s freeze (well past the original threshold): full recovery.

HIGH: InputLeadController's release logic was gated on its own past
attacks (lead > LEAD_MIN) rather than the real server-reported depth, so
a backlog it didn't itself cause was never drained. Fixed to gate on
actual depth vs target.

MEDIUM-HIGH: the rate limiter's "N consecutive over-budget seconds"
streak hard-reset to 0 on any clean window, letting a duty-cycled flood
(burst, one clean window, repeat) sustain ~33x budget indefinitely with
zero warnings. Replaced with a leaky-bucket accumulator immune to the
same evasion by construction.

MEDIUM: the seq > server_tick + 20 guard compared two unrelated clock
epochs (server process uptime vs. client's own from-zero seq numbering),
so it never actually protected anything on a long-running server and
could silently drop an honest client's input forever. Bound against the
buffer's own last_applied_seq instead.

MEDIUM: InputJitterBuffer.stalled was computed but never reached the
wire - the one signal that would have made the ring-overflow bug visible
anywhere. Now wired through _ship_to_net_body_state.

MEDIUM: task 3.6's CI driver's assertions didn't depend on client input
reaching the server at all, so it kept passing with the ring-overflow
bug actively triggered. Added real ship-movement and non-stalled checks,
sampled while bots are still connected (an initial attempt sampled after
their own legitimate disconnect, which starves identically to the bug).

LOW-MEDIUM: a lead change silently mislabelled _input_history's older
entries, since the wire format has no per-entry seq field. Fixed by
handling each delta case (ordinary/release/attack) on its own terms.

LOW: bandwidth and snapshot-loss overlay metrics froze at their last
value during a total outage instead of decaying - exactly when they
matter most. Both now report honest post-outage values.

LOW: a guard comment on NetworkManager._ping misdescribed the actual
disconnect_peer() arguments in use. Corrected.

New permanent regression tests: test_ring_overflow_resyncs_to_fresh_data
_instead_of_starving_forever, test_release_drains_a_backlog_it_never_
caused_itself, and client-abuse-flood-dutycycle (reproduces the exact
duty-cycle evasion). Full regression suite, including the net-sim-latency
milestone gate, all abuse roles, and the CI driver, re-run clean after
every fix.
2026-08-20 15:28:44 +01:00
Josh Creek 10040f7339 docs(multiplayer): close out Phase 3 in multiplayer-todo.md
Documents all seven Phase 3 tasks (3.1-3.7) with DONE status and
verification evidence, updates the top-level status summary, and records
the phase gate as met - re-verified today under the gate's own exact
condition (--net-sim-latency 80 --net-sim-loss 0.05) on both the human
smoke test and the two-bot CI driver, not just the looser conditions
used during individual task development.

Adds one new gotcha (#38): GDScript lambdas capture enclosing locals by
value, not by reference, which silently broke two separate Phase 3 test
scripts' own disconnect-detection assertions this session (the
production disconnect logic was correct both times; only the test's own
flag-capture pattern was wrong).

Also records a deliberate scope decision for task 3.4: server-side
input_lead enforcement from arrival times was scoped down to
observability rather than built as active enforcement, since the
concrete security requirements (rate limiting, malformed-packet
counting, seq-range rejection, disconnect policy) already close the
load-bearing gaps and the doc's own text calls the remaining edge
"small" - flagged to revisit once Phase 4's prediction work exists to
judge against.
2026-08-20 13:43:49 +01:00
Josh Creek 14698d4ccb fix(multiplayer): adversarial review fixes for Phase 2
An Opus subagent's adversarial review of Phase 2 found real bugs the
smoke tests couldn't catch, since constant-velocity dead reckoning still
moves a ship far enough to pass a "moved > 1.0" check:

- The interpolator never actually interpolated. NetInterpolator.to_tick()
  assumes physics_frame * TICK_MS == Time.get_ticks_msec() on the server,
  which is off by a steady ~45-55ms in practice (real startup work before
  the first physics step, widened by any dropped tick). Every sample_at()
  call took the extrapolation branch, 100% of the time, defeating the
  interpolation buffer entirely. Fixed with a shared, min-filtered rolling
  bias estimate in networked_match.gd, applied before every to_tick() call.

- Goals caused a ~27m visual slide: _reset_gen was bumped before the
  queued teleport actually landed, so the client's buffer-clear kept
  exactly the stale in-goal sample and lerped a slide to the next, real
  one. Fixed by tracking the tick the goal was detected on and only
  bumping the generation once strictly later ticks confirm the teleport
  has landed - a naive "next _physics_process" boolean flag doesn't
  work, since a goal Area's body_entered fires before that same tick's
  _physics_process runs, not on the next one.

- _local_input_sampler (a Node, never added to the tree) was never freed
  - this was the unexplained "3 resources still in use at exit" warning
  on every Phase 2 test run.

- Ball angular velocity decoded 8x too small (rescale_avel was never
  called); get_server_time_estimate_ms() was used before the clock had
  synced; net_sim.gd's delayed-send timer stopped ticking while the tree
  was paused and didn't check connection status before firing;
  _broadcast_snapshot's ball index could silently break if a ship were
  ever despawned; declared-but-unemitted HUD lifecycle signals showed a
  permanently frozen timer widget.

Also confirmed, empirically, several things the review checked and found
fine: a hostile client sending malformed input cannot crash the server,
skipping GameMode's super() drops nothing load-bearing, deterministic
slot assignment is correct with 2 real simultaneous clients, and RPC
authority enforcement genuinely rejects a forging client.

All fixes verified with real two-process runs (including forcing an
actual goal and reading the server's own broadcast stream) and temporary
instrumentation, removed once each fix was confirmed. Full Phase 1 +
Phase 2 regression suite, including the net-sim-latency milestone gate,
re-run clean after every fix.
2026-08-20 12:43:33 +01:00
Josh Creek 7b150ef72e feat(multiplayer): task 2.8 net_sim.gd, close out Phase 2
New NetSim autoload: seeded, CLI-driven (--net-sim-latency/-jitter/-loss/-dup)
latency/jitter/loss/duplicate decorator, a true no-op passthrough unless a
flag is set. Wraps MatchSim.send_input/send_snapshot per the design doc's
scope, plus NetworkManager's ping/pong so the already-tested RTT/clock
measurement becomes the acceptance signal for "raises observed RTT" without
waiting on Phase 3's per-peer snapshot echo.

Two real bugs found while building and verifying this against Phase 2's own
milestone gate (a real match under --net-sim-latency 80 --net-sim-jitter
20, not just LAN): a timestamp captured inside a delayed RPC closure
silently ate that side's own added delay out of the round-trip
measurement instead of adding to it; and a delayed send whose target
disconnected (or whose own process had already shut down) during the hold
threw RPC errors, since the existing get_peers() filtering only checked
validity at schedule time. Fixed by capturing timestamps before handing
off to NetSim, and by having NetSim re-validate the target at fire time.

Phase 2's milestone gate now passes for real: a full 1v1 under simulated
80ms latency / 20ms jitter still shows clean server-authoritative
movement and zero RPC errors. Full Phase 1 + Phase 2 regression suite
re-verified clean with NetSim present but inactive.
2026-08-20 08:50:47 +01:00
Josh Creek 39a41c016c feat(multiplayer): Phase 2 server-authoritative simulation, dumb client
Implements tasks 2.1-2.7: NetworkedMatch spawns a deterministic slot
layout from the lobby roster, the server drives each connected peer's
ship via RLShipController fed by decoded client input and broadcasts
60Hz snapshots, and the client renders everything (including its own
ship) from a per-body NetInterpolator with no local prediction yet.
Dual-time remote entities split collider updates (present-time, for
correct contacts) from $Visual updates (interp-delayed, for smoothness).
Camera/HUD wiring and remote engine-flame VFX fell out of the existing
Ship API for free once snapshots were flowing.

Three real bugs found and fixed while getting a two-process test
green: an RPC method named _input collided with Node's built-in
_input virtual and broke the whole MatchSim autoload from loading;
networked_match.gd never called NetworkManager.poll(), so nothing
sent via RPC in this scene reached the wire despite Phase 1's manual
polling being wired up everywhere else; and a match_config
request/response fallback (added to close a startup race) could
double-deliver once polling was fixed, requiring an idempotency guard.

Verified with tests/networked_match_smoke: a real headless two-process
host+client run shows the client rendering 31m of server-authoritative
movement from a held forward-thrust input, with thrust_z=1.0 confirmed
on the interpolated snapshot mid-drive and camera/HUD both wired.
Full Phase 1 regression suite re-run clean alongside it.

Task 2.8 (net_sim.gd latency/jitter/loss decorator) is not yet done;
Phase 2's own gate needs it before it's fully met.
2026-08-20 08:42:13 +01:00
Josh Creek 4533da34e0 feat(multiplayer): Phase 1 transport, connection, and lobby
Lands tasks 1.0-1.8 of multiplayer-todo.md: the pure-function test runner,
net_codec (wire format quantizers/pack-unpack), NetworkManager (ENet
transport, manual polling, min-RTT clock sync), MatchNet (handshake,
protocol/tick-rate gating, roster with team+ready state), lobby.tscn (team
columns, switch team, ready toggle), server_boot.tscn (headless dedicated
server with structured logging and an overrun watchdog), and main_menu.gd's
Host/Join-by-IP UI (connecting overlay, cancel, bounded failure path).

Followed by an adversarial review (Opus subagent) that found and fixed two
real bugs - an unvalidated player_name broadcast that let one client's
oversized name head-of-line-block the reliable channel for everyone, and a
server-side roster leak across a host/re-host cycle - plus three gaps in
the test suite itself where a claim of "verified" wasn't actually backed
by what the test checked. All five two-process smoke tests plus the
pure-function suite are green with the strengthened assertions in place.
2026-08-20 08:18:59 +01:00
Josh Creek e83bb4fa0c fix(multiplayer): revert stray match.tscn team_size, record 0.15b real-hardware results
match.tscn had picked up team_size=3 from an earlier diagnostic dry run,
which would have made every normal Match spawn 3v3 instead of 1v1 -
reverted to the scene's intended default.

multiplayer-todo.md: task 0.15b's real blocker turned out to be measuring
on a Mac (Apple Silicon's tile-based GPU architecture gave a misleading,
undifferentiated cost profile). Re-ran the same 6-ship-match profiling
harness on reference hardware (RTX 3090) via a real GPU-bound X session -
results in §5.5.2 show the game comfortably clears 500+fps with every
effect on, and SDFGI/SSIL dominate the (now tiny) effects budget as
originally expected. This closes 0.28 (physics threading) as unnecessary
- there's no frame-time variance problem on reference hardware to fix -
and reframes 0.26 (bake GI) as a real but smaller win than assumed, worth
revisiting on lower-end hardware. Also corrected two stale/inaccurate
task rows (0.13, 0.17) found while reconciling the doc against what
actually landed.
2026-08-19 23:16:21 +01:00
Josh Creek 04691aaa48 chore(multiplayer): Phase 0 refactors + graphics/perf settings groundwork
Lands the non-networked Phase 0 tasks from multiplayer-todo.md (ship/camera/
arena refactors, sim constants, background FPS handling) plus a first pass
at exposing graphics/performance settings (presets, resolution scaling,
vsync, FPS cap, perf overlay) and a GPU profiling harness for the
real-hardware follow-up in task 0.15b.
2026-08-19 22:37:17 +01:00