MEASURED LIVE (common_libs/tests/measure_fire_ghost_lag.py, 4 sessions, 1777
matched ghost spawns, both movers): the server dispatches a turn's fire AFTER
our go() for that same turn, so a turn-T shot's energy drop first reaches our
scan at turn T+1 — and a bullet takes its FIRST step during the turn it is
fired, so the true bullet is already one whole bullet step (11-20 px) downrange.
Both movers place the ghost at the SCANNED enemy position (where the bullet was
born), so the whole ghost trajectory is the true one shifted one turn later and
the arrival deadline is a full tick late.
MEASURED: detection lag +1 tick on 100% of 1777 matched spawns; ghost-vs-
observer displacement 19.06 px mean / 22.00 p90 (tfil) and 16.08 / 21.81
(strafe); arrival-deadline error 0.99 / 0.77 ticks. NOT a rendering artefact:
the draw/advance order is correct (advanceBullets -> detectFires -> build).
THE FIX: TR_FIRE_LAG (int, default 0 = today byte-for-byte) in the shared
fire_tracker, applied by both movers at spawn: x = origin + dir*speed*lag.
The deadline needs no separate change — both movers derive it from the ghost's
own position, so a correct position gives a correct deadline.
WITH IT: displacement 19.06 -> 5.37 px mean (the residue is the enemy's own
<=8 px scan staleness) and the deadline error 0.99 -> 0.06 ticks.
Guards: test_tfil_commit_env 77 -> 87 checks (default golden parity, exact
n-step back-date, deadline shortens by exactly lag, junk/negative degrade to 0,
reaped exactly one tick earlier); test_env_report + test_env_dotenv green.
TR_FIRE_LAG registered in env_report + knownEnvNames + .env.example +
docs/env_reference.md. Live A/B pre-registered in docs/movement_campaign.md
(Batch 8) with its MDE stated up front; arms tools/ab/arms_fire_lag.txt.
TR_FIRE_DIAG gains a per-round ROUND line (the tick->getTurn anchor) and a
per-spawn SPAWN line (the ghost's drawn position).
The picker scored candidates on pathMaxHeat alone and then drew uniformly
among the survivors, so a mirror-side tile was as likely as a straight-ahead
one. Added a continuous turn cost as a DRAW WEIGHT applied only after the
hard heat filter:
w = max(1, round(1 + TR_TFIL_TURN_BIAS * (1 - max(0,|turn| - REF)/180)))
- TR_TFIL_TURN_BIAS (default 0) is the odds ratio straight-ahead vs 180 deg;
TR_TFIL_TURN_REF_DEG (default 45) is where the penalty starts. Both
default-off-effect: the default-path golden in test_tfil_commit_env.nim is
unchanged and still passes.
- Turn cost is NEVER folded into the heat score. The filter stays hard.
- The draw stays random (j51 measured an argmin worse); every weight is
floored at 1, so the pool can never be emptied and bias 0 is exactly the
shipped uniform draw.
- |turn| now travels on the ScoredTile, and the commit log gained turn /
minturn / promote so a caller can measure the regret of the draw.
Guards: 51 -> 66 checks (an absurd 99:1 bias never rescues an over-threshold
tile; mean |turn|, draw regret, >90 and mirror-side shares all fall; path
heat does not rise). env_report + .env.example updated.
The owner's live-GUI report was correct on all four counts, and all four are
one bug: the commitment is cancelled by our own tile-boundary crossing
(96.1% of picks, 3793/3946, mean hold 5.06 ticks) while the bot is still
accelerating, and the picker is an unconstrained uniform draw over every
safe tile, so the new target can land in the mirror direction at |speed| < 4.
New knobs, all env-gated and default = today's behaviour (byte-for-byte
default parity guard re-run and green, 51 checks):
TR_TFIL_COMMIT_ARRIVAL hold the committed tile until we are ON it; the
tick knob becomes a MINIMUM dwell. 0 = shipped.
TR_TFIL_COMMIT_MARGIN leave only if the best alternative is at least
this much cooler on the same pathMaxHeat scale.
0 = shipped.
TR_TFIL_NOREV_SPEED while |speed| is below this, a mid-flight switch
may not take a tile >90 deg off the travel
direction. 0 = shipped. norevPool() never returns
an empty pool: with every candidate behind us it
takes the least-bad turn.
Offline gate (recorded DrussGT fixture, 20026 ticks): mean hold 4.1 -> 24.0
ticks, abandoned-before-arrival 92.8% -> 40.5%, committed tile actually
reached 3.3% -> 17.2%, opposite-direction slow mid-flight switches 394 -> 64
(-84%). 'TR_TFIL_TILE_REPLAN=off' alone - what cc11ede's arm B already tried -
only gets the hold to 13.6, which is why that A/B could not find this.
strafe is untouched: it imports only heatDecay/bulletMagScale/Pillar*, none
of which this touches. TR_MOVEMENT default stays strafe. Registered in
env_report.nim + knownEnvNames() + .env.example. Arms pre-registered in
docs/movement_campaign.md and tools/ab/arms_tfil_commit.txt.
The default mover painted a 30/10 radiance blob on the arena centre even
though the arena has NO physical pillar there, creating a 4x4 tile
(144x144 px) exclusion zone over open centre floor. Set
PillarHotness/PillarRadiance to 0/0 in the shipped default (matching the
ring variant) and add TR_TFIL_PILLAR_ON=1 to restore the old 30/10 field
for A/B without a rebuild; registered in env_report.
Because the shipped default legitimately changed, the default-path parity
golden (fixtures/tfil_commit_default.golden) was regenerated from the NEW
default, with an explicit 'deliberate default change' note in the test so
a future failure is treated as a real regression.
Also register the three env reads job j102 added in common_libs/bitbrain
(TR_BITBRAIN_MODE / _DECAY_EVERY / _DECAY_SHIFT), which the env-report
guard was failing on.
Verification: test_env_report all green; test_tfil_commit_env 30/30.
The tile-change replan cancels the 15-tick movement commitment whenever OUR
tile changes. With GridSize=36 and speed up to 8 px/tick that is every ~5
ticks, so the commitment is cancelled by the motion it commands (measured:
96.9% of picks were tile-change replans, 33.8% of picks reversed direction).
Adds four env knobs, every default reproducing the shipped mover
byte-for-byte:
TR_TFIL_TILE_REPLAN self (default) | off | enemy
TR_TFIL_COMMIT_TICKS 15 (default)
TR_TFIL_NO_REV 0 (default)
TR_TFIL_COMMIT_LOG off (default, JSONL per-tick diagnostics)
- `off` honours the commitment; the danger replan stays the safety valve.
- `enemy` keys the cancel to the TARGET's tile displacement (the intent the
original comment claimed).
- `TR_TFIL_NO_REV` down-weights (never filters) tiles >90 deg from the travel
direction; the pool can never be emptied.
Default-path parity is guarded by test_tfil_commit_env.nim, which replays
tools/fixtures/tr_drussgt_vs_modularbot.jsonl and diffs every move command
against a golden generated from the pre-change build (git archive f842ac0).
env_report known-name list updated for the four new names.
SirStone