The MadCat (and every leg-mech) leans -8deg into a walk / -11deg into a run --
an authored jointhip (hingex) pose in the EXTERIOR gait clips that the walk/run
CYCLE clips never rebind, so it HOLDS. The 1995 game keeps a separate INTERIOR
('i'-suffix) clip set for the mech you PILOT: those shake jointshakey (cockpit
rattle) and OMIT jointhip, so your own view stays level while everyone else sees
you lean. The port had this entirely dead -- the local cockpit mech pitched
-8deg into the ground (user-reported "staring at the ground").
ROOT CAUSE (two stacked bugs):
- The authentic ctor clip-set gate (@part_012.c:10308-10320) was reconstructed
as no-op stubs: LoadLowDetailBody/LoadHighDetailBody MISLABELED the
FUN_004a80d4/86c8 GAIT-CLIP loader addresses as a "body LOD" pair, so the gate
did nothing and a separate unconditional LoadLocomotionClips always loaded
EXTERIOR clips.
- LoadLocomotionClipsExt (the interior loader) was a stub aliased to the
exterior loader.
FIX:
- Reconstructed the real 4-char INTERIOR loader (byte-exact vs @004a86c8; the
'i'-suffix table dumped from the exe @0x10d74d: swri/wwri/wwli/...; all 18
base clips confirmed present in BTL4.RES for mad/blh/ava).
- Fixed the ctor gate: getenv("L4VIEWEXT") || (instanceFlags&0xC)==4 -> exterior
(replicant / forced external view); else -> interior (local cockpit master).
Removed the mislabeling no-op stubs.
- PORT ADAPTATION (MaintainViewClipSet, per-frame in PerformAndWatch): the port
never sets the replicant COPY bit (all MP mechs build as local masters --
heat-sim/scoring/torso-watcher-connect all run on both, by design), so the
ctor gate lands everyone on interior. Pick the set by VIEWPOINT instead: the
mech you pilot keeps interior (level cockpit), every other mech flips once to
exterior (the lean). Reloads only on a viewpoint-status change; the sets
share stride data so the swap is seamless. Model pointers stashed at ctor.
VERIFIED live (BT_HIP_LOG probe): your walking mech writes jointhip=0 (level);
the peer's replica in the other pod's view leans at exactly -8.0/-11.1deg --
the authored clip values. A/B control: L4VIEWEXT=1 forces the walking master
back to 74 sustained -8/-11 writes.
KB: locomotion.md ("NO walk lean" audit conclusion CORRECTED -- the lean is
authored + sustained + clip-set-specific), asset-formats.md (.ANI parses
pitch/yaw/roll for all joint types; KeyJointPos translation; cycle clips carry
no pitch), open-questions.md (item closed).
Co-Authored-By: Claude Fable 5 <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>
