Hypothesis (user's): pushing an enemy toward a wall makes it predictable, which
both enables a ram and raises our gun hit rate. Measured offline over the
committed DrussGT fixtures using REAL server event attribution (an events
sidecar survived: tools/robocode_shim/evidence/tr_drussgt_vs_modularbot.events.json,
2534 fires / 229 hits; per-round event tick joins the fixture global tick at
global = round.startTick + tick - 2, verified exact over all 2534 fires).
M1 - cornering does NOT raise hit rate.
REAL attribution, all 1134 ModularBot shots, bucketed by DrussGT's distance
to the nearest wall at fire time:
<=30px 69 shots 5 hits 7.25%
30-60 336 18 5.36%
60-120 555 26 4.68%
120-250 172 11 6.40%
>250 2 0 0.00%
TOTAL 1134 60 5.29%
Adjacent(<=60) 5.68% vs Open(>60) 5.08%, z=+0.435 -> NOT significant.
Per-round ranges fully overlap (adjacent 0-18.2%, open 0-9.6%).
Virtual per-gun within-gun check: most guns neutral-to-negative; only DecayGF
favours it. Across all 10 fixtures every one of 12 guns scores LOWER adjacent
(range-confounded, directional only).
M2 - a wall-adjacent enemy is LESS predictable, not more.
30-degree tolerance, uniform chance 16.7%, adjacent vs open:
keep-direction (1 tick) 93.35% vs 95.88% z=-13.82
turn-persistence 87.6% vs 90.9%
constant-velocity err H=10 45.9% vs 25.7% (1.8x MORE deviation)
"move away from nearest wall" 1.1% vs 8.4%
"move toward centre" 0.4% vs 3.0%
Wall-adjacent DrussGT reverses more and deviates from constant-velocity ~1.8x
more. It does NOT flee the wall - it surfs perpendicular. Base rate of
wall-adjacency: 20.2% of moving ticks.
M3 - the ram is a near-zero-frequency opportunity against DrussGT.
Strict contact (<=36px): ZERO ticks in all 10 fixtures. Closest global
approach 39.1px. In the primary fixture (ModularBot vs DrussGT) the closest
approach was 118.7px - 0 ticks <=80px, 0 near-contact episodes, and ZERO ram
collisions in 15 rounds. Real ram collisions anywhere in the corpus: 2 total
(drussgt_vs_ramfire 1/20 rounds, tr_drussgt_vs_crazy 1/10), each a ONE-SHOT
0.6 energy to both bots, no sustained multi-tick stream.
CORRECTION TO AN EARLIER CLAIM: ram damage is 0.6 per CONTACT EVENT, not
0.6/turn sustained. The efficiency ratio (0.6 damage for 0.6 energy taken,
scored 2.0/pt) still beats firing, but the magnitude is 0.6 vs 16 for a p=3
bullet hit, and against DrussGT the frequency is zero.
CAVEAT (from the analysis): the fixtures capture DrussGT's NATURAL wall
behaviour, not an enemy being actively pushed into a corner by a rammer, so the
exact scenario is not directly represented. But M3 shows we never get close
enough to push in the first place - ModularBot's closest approach in 15 rounds
was 118.7px, so the <50px ram trigger has never fired against this adversary.
Adds two reusable offline instruments:
- measure_cornering_guns.nim (replays a fixture through the real VirtualTracker,
attributing each resolved virtual bullet to its fire-tick wall bucket)
- measure_cornering_ram.py (real-event join, predictability, ram base rate)
Neither edits offline_range.nim; the 12/12 deterministic-gun contract is
untouched and was not re-run (it requires a live battle).
