Audio Phase 4c (AUDIO_FIDELITY F17/F19): impact scaling + the authored footstep feed

F17 CollisionSpeed (binary id 24 @0x4B4): real member captured as
|worldLinearVelocity| when the contact accumulator arms (0->1) -- the authored
AttackVolume [0.9,1] / Brightness [0.7,1] scales over impact speed [0,25] now
make harder hits sound louder and brighter.  ReduceButton (id 46 @0x340): real
watchable member (the keyboard rig never presses it).  UnstablePercentage
stays deferred: its sway/overspeed model @0x3F0 is the known gyro-ledger gap
(live writer unexported); binding without the model would be a stand-in.

F19 footstep feed (the invention is dead, long live the authored chain):
new [motionscalecfg/motiontrigcfg] traces recovered the authored configs --
EVERY motion watcher extracts |linearMotion| (motionValue=3); the footstep
volume mixer is fed by LocalAcceleration [0,10] -> ctl100 (per-stride kick)
+ LocalVelocity [0,0.6] -> ctl101 (0.4 base while moving).  The port never
wrote Mover::localAcceleration, so ctl100 read 0 and the old mech2.cpp
step-intensity broadcast (patch-sniffing, invented curve) fought the live
authored scale.  Now: localAcceleration.linear = d(published velocity)/dt --
EXACTLY the binary's derivation ((avgVel - prev)/avgDt into +0x1e4,
part_012.c:15186-15195) -- and the broadcast is REMOVED.

Regression (30s, walk throttle): stable; footfalls deliver through the
wholly-authored chain with per-stride VARYING gains (0.61/0.72/0.62 -- real
step dynamics, impossible under the old constant-curve invention).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This commit is contained in:
arcattack
2026-07-16 14:11:36 -05:00
co-authored by Claude Opus 4.8
parent 21378ec132
commit 9dcb4752de
5 changed files with 57 additions and 69 deletions
+22
View File
@@ -3692,8 +3692,23 @@ void
// velocity the same way; this filter reconstructs that stage.
{
Scalar alpha = dt / (dt + 0.25f);
Scalar fwdPrev = fwdSpeedFiltered;
Scalar vertPrev = vertSpeedFiltered;
fwdSpeedFiltered += alpha * (fwdSpeed - fwdSpeedFiltered);
vertSpeedFiltered += alpha * (worldLinearVelocity.y - vertSpeedFiltered);
// (AUDIO_FIDELITY F19) publish localAcceleration EXACTLY as the
// binary does: the derivative of the (averaged) published
// velocity (part_012.c:15186-15195 -- (avgVel - prev)/avgDt into
// localAcceleration.linear). The AUTHORED footstep chain reads
// |localAcceleration.linear| [0,10] -> mixer ctl100 (the
// per-stride kick) on top of |localVelocity| [0,0.6] -> ctl101
// (the 0.4 moving base); with this member never written the
// kick input read 0 and step volume lost its dynamics.
if (dt > 1.0e-4f)
localAcceleration.linearMotion = Vector3D(
0.0f,
(vertSpeedFiltered - vertPrev) / dt,
-((fwdSpeedFiltered - fwdPrev) / dt));
}
localVelocity.linearMotion = Vector3D(0.0f, vertSpeedFiltered, -fwdSpeedFiltered);
localVelocity.angularMotion = Vector3D(0.0f, turn * authTurnRate, 0.0f);
@@ -5781,7 +5796,14 @@ void
// impact, so accumulate InitialHit(1) -- the decomp's dominant `else` branch;
// upgrade to the full 1-vs-2 split once 0x240/0x244 are reconstructed. [T3]
if (collisionTemporaryState == 0)
{
collisionTemporaryState = 1;
// (AUDIO_FIDELITY F17) capture the impact speed for the authored
// CollisionSpeed volume/brightness scales ([0,25] -> harder hits
// sound louder + brighter). |worldLinearVelocity| at the arming
// contact = the impact speed.
collisionSpeed = worldLinearVelocity.Length();
}
}