New L4AUDEFX bridge (OpenAL Soft ALC_EXT_EFX): one EAXReverb aux slot at the
authentic AUDIO.INI global_reverb_scale (0.3) + a scratch AL_FILTER_LOWPASS
(params copied at attach).
F9 filters (was: computed then thrown away -- everything full-bright at all
distances): Dynamic3D ExecuteModel drives GAINHF from highFreqCutoffScale x
brightnessScale x maxMIDIFilterCutoff, UNGATED (decomp part_008.c:7496,
7589-7604 -- every moving 3D sound dulls with distance per the AUDIO.INI
knee-60/exp-2.0 model); Static3D from brightness x max (:7831-7884); Direct
inside its existing gated NRPN-rate block. AWE 100-8000 Hz curve -> EFX
5 kHz-reference gainhf via a 2-pole approximation [T3 curve, endpoints exact].
F11 reverb (was: bone-dry everywhere): 3D patch sources attach an aux send at
Start, exactly where the original sent CC91 = global_reverb_scale
(part_008.c:7278-7394); Direct cockpit sources keep CC91=0 -- dry. The
wet-exterior vs dry-cockpit contrast is back.
F12 placement (was: every cockpit sound dead-center): DirectPatchSource
Start places sources by the authored 6-value position enum (front/rear card
+ pan CC10, decomp @00463848/@004638a8) as listener-relative directions,
composed with the zone L/C/R pan. New PatchResource GetBankID/GetPatchID
pass-throughs (the LOD accessor is protected).
Regression (35s drive+fire): EFX READY, stable, deliveries unregressed, no AL
errors.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
F3 distance: alDistanceModel(AL_NONE); restored the commented authored
distance multiply in Dynamic3D::CalculateSourceVolumeScale, added the same
override to Static3D, dropped the (now inert) AL_MAX_DISTANCE writes. Far
battle audio follows the authored knee/rolloff curve again, and the volume
cull / voice steal / ducking chains are distance-aware.
F4 volume law: AL_GAIN = volume_scale^2 at all 3 per-frame sites (Direct/
Dyn3D/Static3D) -- the GM CC7 squared curve; linear was ~+6 dB at mids.
F10 doppler: alDopplerFactor(0) (AL's model ran wrong constants + sign-
inverted velocity: approaching sources pitched DOWN); the AUTHORED
dopplerCents (AUDIO.INI range/speed-of-sound model, decomp-proven consumer
part_008.c:7466) now adds into the Dynamic3D pitch chain.
F15 ConfigureActivePress: published at the MechSubsystem BASE (binary id 2,
descriptor @0x50de5c -> +0x110); renamed the misnamed vitalSubsystemIndex
member (the weapon ConfigureMappables handler already drives it 0/-1).
Removed the invented Sensor/Myomers duplicates and RESTORED their byte-
exact layouts (0x328/0x358 allocs + asserts). MechWeapon's pinned-id pad
absorbed the +1 chain shift -- which matches the binary's own numbering.
F18 cook-off warning: AmmoBin FireCountdownStarted -> the existing
cookOffArmed @0x18C (binary table @0x512600); the countdown klaxon can fire.
F20 zoom blip: L4MechControlsMapper publishes TargetRangeExponent -> the live
@0x1a4 zoom member (own table chained to MechControlsMapper).
KB: replaced the bogus divisionParameters+0x10 rate read with
SystemClock::GetTicksPerSecond() (FUN_0044e19c is GetFrameRate -- original
audio frames were CLOCK TICKS).
Regression (35s drive+fire): stable; ConfigureActivePress binds real on all 9
subsystems (idle -1, zero pad redirects); FireCountdownStarted +
TargetRangeExponent bind live members; attrnull 53 -> 41; chirp still dead;
footfalls still fire (gain now correctly squared).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The whole pitch system existed but was discarded: NoteAudioHandler captured the
MIDI note, ExecuteModel computed relativePitch from the control-chain cents --
and NOTHING ever called alSourcef(AL_PITCH). Every sample played at root.
Consequences fixed:
- The load-time 'chirping' ambience: an authored looped sequence (div=120
tempo=160, note 51 events on bank1:83) plays a rhythmic tick pitched ~9
semitones DOWN; at root it was a high click ('chirp'). Identified live via
the new BT_AUDIO_DUMP playing-source tape + user ear-match at cadence.
- Engine now revs: EngineMotor pitch rides the throttle (measured 1.0 -> 1.12).
- All sequence-authored patterns (alarms/klaxons/ambience) regain their pitch.
Implementation: BTNotePitchFactor(note) = 2^((note-60)/12); applied at all 3
patch-source StartImplementations (fresh attach) and all 3 ExecuteModels
(combined with the control-chain relativePitch, clamped 0.5..2.0 as before).
Uses the existing AudioSource::GetCurrentNoteValue().
Also: [seqcfg] sequence-config dump, g_bufferNames + BT_AUDIO_DUMP live tape
(1/s: every playing AL source with sample name/gain/pitch/loop),
tools/soundboard.py updated mapping.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
User: "when I start moving all the sounds fade away, no footsteps." Diagnosis
chain (all empirical, BT_AUDIO_SPATIAL/BT_ATTRBIND_LOG traces):
- The audio head DOES track the mech (listener-relative positioning verified
while driving) -- not a spatial bug.
- The idle sounds correctly STOP on leaving the standing state; the MOVING
sounds never started because every POLLED audio watcher was dead:
the reconstructed Mech::PerformAndWatch replaced the engine performance but
dropped the ExecuteWatchers() step from the engine tail (Simulation::
PerformAndWatch = Perform -> ExecuteWatchers -> WriteSimulationUpdate).
Only PUSHED StateIndicator watchers (SetState->Execute) ever fired -- which
is exactly why state sounds worked but footsteps/motion-scaled audio didn't.
FIX: poll ExecuteWatchers() (AreWatchersDelayed-gated) before the update
write. Immediately unlocks the polled family: MissileLoaded01/LaserLoaded01
ready dings, ProgramButton01, motion scales (PlayNote 15 -> 30 per run).
- FootStep (0x1e) backed REAL: was the inert attrPad (an AudioLogicalTrigger
polls it -- threshold-crossing pulse per foot plant). New footStep member,
pulsed by SetBodyAnimation on entering any locomotion clip 1..0x17 (runtime
stride alternation MEASURED as body states 12<->13 -- the enum-name numbering
does not match runtime clip ids), decayed by IntegrateMotion (~1/3 s).
- Footstep volume is speed-scaled (AudioMotionScale on LocalVelocity): at
standstill the transient start computes volume 0 and the renderer drops it
(LowAudioVolumeThreshold) -- so footfalls are audible at real walking speed.
Diagnostics kept (BT_AUDIO_SPATIAL): spatial dist/vol per source, CLIPPED/DROP/
START at the request gate, vol=0 factor breakdown, scale->0 sends, trigger
notifications, watcher poll-rate probe.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Clean, self-contained extraction of the BattleTech-specific work from the
reverse-engineering workspace -- engine + game + content + build, with nothing
from Red Planet or the raw archive dumps. Builds green (Win32) and runs the
single-player drive->animate->target->fire->damage->destroy loop out of the box.
Layout:
engine/ MUNGA + MUNGA_L4 shared 2007 engine, carrying our BT render/loader
work (bgfload/L4D3D/L4VIDEO: BSL bit-slice decode, LOD/ground/shadow
models) + image codec; the minimal rp/ headers the audio HAL needs
game/ reconstructed BT logic + surviving-original BT source + fwd shims
+ WinMain launcher
content/ full runtime tree (BTL4.RES, VIDEO/, GAUGE/, AUDIO/, eggs, BTDPL.INI)
docs/ format specs + reconstruction ledgers
reference/ raw Ghidra pseudocode (recon source-of-truth) + decomp exporter
tools/ MP console emulator + map/resource scanners
One top-level CMake builds munga_engine lib + bt410_l4 game lib + btl4.exe.
All paths relativized (186 fwd shims + ~437 CMake abs paths -> repo-relative);
DXSDK is the one external, overridable via -DDXSDK. Verified: builds to a
byte-identical 2.27MB exe and runs combat (TARGET DESTROYED, 0 crashes) against
the bundled content.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
