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.
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.
Josh Creek