myomer damage reaches the wheels, legs gimp at half structure, reverse refuses -- and an ODR trap unmasked (#75/#78)

The speed-demand site (MechControlsMapper::InterpretControls) now applies the
drive scale the mover's feed roster applied in 1995: speedDemand multiplies by
the myomers' live speedEffect (gear ratio, thermal curve, 1 - zone damage, via
the BTMyomersDriveOf bridge) and, while GIMPED, by 0.5 [T3: VGL Lynx's
"roughly 50%", BT_GIMP_SPEED overrides]. The gimp states were already being
raised -- mechdmg sets graphicAlarm 3 (left) / 4 (right) when a LegDamageZone-
flagged zone crosses half structure -- but nothing downstream ever saw them.
While gimped, reverse input is refused ("reverse disabled"), matching the
old-timers' account; the pod's audio cue rides the alarm's watchers.

Bench, one trajectory, arithmetically exact: a deterministic right-leg ramp
(the new BT_SELF_DAMAGE_ZONE harness) crosses 0.5 and the demand goes
44.837 -> 6.726 = 44.837 x 0.5 (gimp) x 0.3 (a crit-chewed myomers from the
same ramp -- the #80 crits composing with #75's scale, unprompted).

The reason "nothing downstream ever saw them" is the real find of the night,
now gotcha #23: AlarmIndicator is typedef'd to DIFFERENT TYPES per header
family -- mech.hpp says ReconAlarm (4 bytes), heat.hpp says GaugeAlarm (0x54)
-- so Mech::graphicAlarm and EVERY member after it sit at different offsets
depending on a TU's include order. mechdmg wrote level 4 and read it back;
mechmppr read 0 from the same object, same expression. No compiler error can
catch it: each TU only ever sees one definition. Until the split is audited,
cross-TU reads of the gimp level go through BTMechGimpLevel (compiled in
mechdmg's TU) -- and the same split-brain explains why the port carries the
binary's ONE movementMode cell as two live members (engine simulationState vs
graphicAlarm level) that never meet.

Also landed en route: the Myomers un-powered self-repair observed healing in
the field logs at exactly 0.011 x the authored Explosive scale per tick --
the 2026-07-29 reversal confirmed live; and Mech message 0x15 "RealMaxSpeed"
raw-decoded (@0x49f604: sets mech+0x7a0 from the message unless the +0x7a4
latch holds -- a console-tunable top speed).

Open on #78, documented in locomotion.md: the Gimp animation clips (authored
keys in the binary's model-record parser; mech2's state enum vs mech3's
reverse-fix disagree about slots 0x12-0x17 -- reconcile before wiring) and
the audio-cue binding.

Diags: BT_SELF_DAMAGE_ZONE, BT_DRIVE_LOG, BT_GIMP_SPEED.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

context/decomp-reference.md

@@ -473,6 +473,9 @@ default-ON (`'0'` disables).
 | `BT_SELF_DAMAGE=<dps>` | dispatch an unaimed `TakeDamage` at your OWN mech once a second, through the real `Entity::Dispatch` path, so the whole RESPAWN family is bench-testable solo (nothing else can kill the local pilot: `BT_MP_FORCE_DMG` only targets replicants). **Latches off at first death** so everything after the respawn is the respawn's doing, not the harness still shooting you |
 | `BT_POWER_DETACH_TEST=<name\|1>` | drop a subsystem's voltage link + force Auto, so the auto-hunt must recover it. `1` = first powered subsystem to tick; a NAME (`PPC_1`, `Myomers`) targets one, which is what proves FAILOVER to a different generator rather than a same-generator re-attach |
 | `BT_AUDIO_SOURCES=<n>` | request `n` OpenAL mono sources instead of the driver default (~256). **Opt-in on purpose** — the cap doubles as a governor, and with EFX reverb live a higher ceiling means more simultaneous voices mixing during heavy combat. Measure frame time. See [[wintesla-port]] |
+| `BT_SELF_DAMAGE_ZONE=<n>` | aim the BT_SELF_DAMAGE harness at an explicit zone (-1/unset = the lottery) -- ramps one zone deterministically past thresholds (#78 bench) |
+| `BT_DRIVE_LOG` | the demand-site drive scale: `[drive] n/drive/mm/dmd/mech` ~1Hz (drive = myomers speedEffect x gimp; mm = the gimp level via BTMechGimpLevel) |
+| `BT_GIMP_SPEED=<0..1>` | override the gimped speed factor (default 0.5 [T3 VGL Lynx]) |
 | `BT_PICK_LOG` | #73 aimed-pick diagnostics: `[segpick]` the segment→zone map at tree build (index, name, zone, sphere), `[pickwin]` the winning zone/score/t per pick (score ~0 = threading the part core, ~1 = envelope graze) |
 | `BT_CRIT_LOG` | #80 crit diagnostics: `[subarmor]` per-subsystem armour/scales/critBonus at ctor (proves the resource keys parsed + the zone got REAL scales), `[critroll]` per landed crit (zone, subsystem, its resulting own-zone level). NB the type-0x1e loader's `[crit]` tag is a different, older log |
 | `BT_DEVICELOST_TEST=<frame>[,crashrepro]` | #35 bench hook. `<frame>` forces the D3D9 DEVICELOST branch at that render frame (+600/+1200 = 3 cycles), driving the REAL `BTResetLostDevice` recovery. `,crashrepro` runs the field null-teardown shape (double `ParticleEngine::Destroy`) — pre-fix this reproduced the field crash byte-for-byte (`Destroy +0x11`, `target=0x0`); post-fix it must log `SURVIVED`. See [[wintesla-port]] §Device-loss |