vwemirror/BT411
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

#83: the COLLISION DIVERT -- type-0 damage prices as internal rattle, never armor

Browse Source 
The crash self-damage reconstruction (9c83a46) exposed its missing second
half: the binary's TakeDamage hub DIVERTS damageType 0 (@0x4a0368) into
FUN_0049ffcc -- an export-gap distributor recovered by raw disasm -- so
collision damage NEVER reaches the zone/armor loop.  Without the divert the
mover's raw kinetic-energy figure (60-ton mech: ~1000+ per wall tap, 90k+ on
a hard slam) fell into the WEAPON loop: 'tapped a wall and died instantly'.

The distributor, byte-anchored: gate on the owning player's advancedDamage
copy (+0x268 -- the manual's 'splash/collision damage' technician setting);
scale = (2000/moverMass) / (100 km/h in u/s)^2 / (1 - elasticity^2)
(tbyte 1/3.6 @0x4a0148; mass @+0x20c; elasticity @+0x244); scaled < 0.5 is
FREE; else Round(2x) sub-hits of 0.5 land on random INTERNAL subsystems
(HeatSink family / Gyroscope / Torso, drawn by collisionCriticalHitWeight
@0x10C) via ApplyDamageAndMeasure (@0x4ac07c).  Bridges: family derivations
(heat/gyro/torso.cpp), BTPlayerAdvancedDamageOn (btplayer.cpp).

Verified: bhk1 wall test -- 94k slam = 4.2 rattle pts in 8 sub-hits, taps
free (0.049 < 0.5), armor untouched.  A/B: arena wall-grind now 0 deaths,
27 rattle events, the limper STAYS GIMPED and peers' replicants re-enter the
gimp cycle between bounded staggers; grass circling unchanged (198 replicant
gimp entries).  [crashdmg]/[colldmg] probes document the pricing.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
This commit is contained in:
Joe DiPrima
2026-07-30 17:04:24 -05:00
co-authored by Claude Fable 5
parent 9c83a468db
commit 14ff3519ac
11 changed files with 184 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files
context/combat-damage.md
+17
View File
@@ -872,6 +872,23 @@ its decomp writers (4668/10512) read as a per-frame state toggle, not a clean co
port's `showDamageInflicted` label is itself a guess; port treats authored `SplashRadius>0` as the
enable. See [[open-questions]].
## Collision damage — the type-0 DIVERT + rattle distributor (#83, 2026-07-30) [T1 disasm/T2]
`Mech::TakeDamageMessageHandler` diverts `damageType==0` (@0x4a0368) into
`DistributeCollisionDamage` (FUN_0049ffcc, export gap, raw disasm `scratchpad/night6/
gap_49ffcc.txt`): collision damage **never reaches the zone/armor loop**. Gate: the owning
player's advancedDamage copy (+0x268, `BTPlayerAdvancedDamageOn` bridge) — the manual's
"splash/collision damage" technician setting. Pricing: `raw × (2000/moverMass)/(100·(1/3.6))²/
(1−elasticity²)` (constants @0x4a0148=1/3.6 tbyte, 2000f, 0.5f threshold; mass@+0x20c,
elasticity@+0x244 by Mover-layout walk); scaled <0.5 = FREE. Above: `n=Round(2×amount)`
sub-hits of amount/n, each landed on ONE roster subsystem drawn by cumulative
`collisionCriticalHitWeight` (@0x10C, MechSubsystem) vs a [0,1) roll, eligibility =
IsDerivedFrom HeatSink-family/Gyroscope/Torso (GUIDs 0x50e590/0x50fdc0/0x510b08; all
MechSubsystem-based, so +0x10C is valid), applied via `ApplyDamageAndMeasure` (@0x4ac07c —
the subsystem TakeDamage virtual into its PRIVATE crit zone). Un-won rolls land nowhere
(weights un-normalized — faithful). Mech-vs-mech ram damage arriving as type 0 prices the
same way. Measured on bhk1 (mass 60000, e=0.2): scale 4.5e-5; a 94k spawn-slam = 4.2 rattle
points; taps free. `[colldmg]` (BT_DMG_LOG) + `[crashdmg]` (always-on, rare) are the probes.
## Key Relationships
- Weapons/roster: [[subsystems]]. Aim source: [[locomotion]] (drive/facing). Effects: [[rendering]].
- P5 forensics: `docs/HARD_PROBLEMS.md`. Data: [[decomp-reference]] §4-5.