Files

T

arcattackandClaude Fable 5 2e9c78d604 Gait: the AUTHENTIC walk lean -- interior/exterior clip sets, level cockpit + leaning mechs (task #59 )

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>

2026-07-13 14:46:22 -05:00

4.0 KiB

Raw Blame History

id, title, status, source_sections, related_topics, key_terms

title

status

source_sections

related_topics

key_terms

asset-formats

Asset Formats — MOD/SKL/ANI/BMF/BSL/textures/gauges/collision

established

PROGRESS_LOG.md §5; docs/ASSET_PIPELINE.md; docs/BGF_FORMAT.md

bgf-format

rendering

locomotion

combat-damage

gauges-hud

MOD

SKL

ANI

BMF

BSL

VTX

SLD

DZM

PCC

GIM

material-ramp

Asset Formats

All reverse-engineered. Geometry (BGF) has its own topic (bgf-format); the full pixel/material spec is docs/ASSET_PIPELINE.md. Full list: docs/PROGRESS_LOG.md §5.

Definition / skeleton / animation

.MOD — INI mech/object definition: skeleton, skins, collision, gauges, physics, animations, class. The .MOD physics (MoverMass/drag/MaxAcceleration) governed thrust VEHICLES + collisions, NOT walk gait (locomotion). [T1]
.SKL — INI joint skeleton. [joint] parent=, Type=(hingex/y/z|ball|balltranslate), Object=part.bgf, dzone=, tranx/y/z, pitch/yaw/roll. Build a DCS tree; neutral pose ≈ translations (pyr≈0). [T1]
.ANI — INI keyframe animation. [HEADER] framecount/framerate(30)/skeletonfile; [frameN] joint→pitch yaw roll radians for EVERY joint type (ANIMTOOL.cpp:140-142 parses the triple as EulerAngles unconditionally — the old "balltranslate→translate" note was wrong [T0]); a balltranslate joint ADDITIONALLY gets a per-frame translation from the separate [KeyJointPos] section (ANIMTOOL.cpp:478-483 packs EulerAngles+Vector3D; JMOVER/seqctl apply SetRotation + SetTranslation). For the root jointlocal, KeyJointPos.y = the gait vertical bob; [RootTranslation] per-keyframe x y z where .z = forward root SPEED (units/s). Walk anims have no baked root translation — forward motion is animation-driven from .z (locomotion). Walk/run CYCLE clips author NO body pitch — root keys are a ≤1.5° roll sway only; the authored LEAN lives in the transition (rwl/rwr/wrl/wrr jointhip ~7-12°) + bmp stagger (~25°) clips (2026-07-13 sweep of all 331 source ANIs). [T1]

Materials / textures

.BMF — DIV-BIZ2 (FILETYPE=1) material+texture LIBRARY (no pixels). Material → DIFFUSE color
- MATERIAL_TEXTURE→texture→TEXTURE_MAP image basename. Tags: 0x18 BITSLICE (BSL slice select), 0x28 ramp ref, 0x26 emissive, 0x30/0x31 ramp def. [T1]
Texture pixels: .tga (Truevision), .vtx (DIV-VTX2, trailing RGB), and .bsl (DIV-BSL2 — a BIT-SLICED container: w*h 32-bit texel words holding SIX independent 4-bit GRAYSCALE sub-images (nibble pair-swapped, byte 0 pad) OR RGB444/RGBA4444 (sliceType 7/8). The BMF 0x18 BITSLICE tag picks the slice, absent=0). Decoding BSL as RGB = the "rainbow/graffiti mech" bug. Reference reader: DivLoader/VGCDivLoader.cpp:323-410; archive-only — in-repo reimplementation: engine/MUNGA_L4/image.cpp. [T2]
.VMF — DIV-VIZ2 material SOURCE. Carries the SCROLL animation + MAP{} image binding for effects (beams/muzzle/smoke/sky). THE key effects asset (rendering). [T2]
material-ramp — the IG board colours no-normal geometry by a 2-endpoint RAMP; details in bgf-format + rendering. [T2]

Collision / damage / subsystems

.SLD collision solids (Block/YCyl/Cone/Ramp/Wedge). Terrain is modeled AS collision volumes; see locomotion ground model + combat-damage. [T1]
.DZM = INI damage-zone→material map (mech skin damage states). .DMG/.TBL damage zones/tables, .SUB subsystems (weapon params — DischargeTime/RechargeRate/WeaponRange), .CTL control maps. [T1]

Cockpit HUD assets (gauges-hud)

.GIM vector MFD/radar line maps + .GAT color table; .PCC ZSoft PCX 8-bit gauge rasters (fonts helv15/helv42, label strips, dials). [T1]

Key Relationships

Geometry detail: bgf-format; pixel/material spec: docs/ASSET_PIPELINE.md.
Consumed by: rendering, locomotion (SKL/ANI), combat-damage (SLD/DZM/SUB), gauges-hud (GIM/PCC).

4.0 KiB Raw Blame History