The death/respawn "blue whirlwind" (tsphere) now matches the original cabinet
photo (capture.png): a smooth spinning lavender vortex with a bright core.
Root cause of the long-standing "radial spokes" artifact was NOT the warp code
but a general engine bug: L4D3D::SetTextureScrolling computed its texture-matrix
offset as scrollDelta * absolute_time, which grows unbounded and collapses UV
float precision -> a smooth scrolled cloud shatters into grainy radial steps.
Wrapped with fmodf(..., 1.0f) (identical under REPEAT tiling, full precision).
This also cleans the scrolling bexp beam grit and any other SCROLL material.
Visual reconstruction (verified against the real 45-vtx TSPHERE.BGF bicone,
offline-rasterized then ported):
- view ON-AXIS (eye centred on the throat) + spin in place -> concentric rings
(decomp FUN_00453dc4 does spin-about-local-Z + submit; the port had stubbed it)
- bintA cloud through a WIDE lavender ramp at full contrast (drawn as SKY);
no geometry "bands", no log-polar twist, no off-axis tornado (all discarded)
- tessellate the 12-facet bicone smooth; isotropic + trilinear; ramp baked into
the texture and drawn SELECTARG1(TEXTURE) to avoid double-tinting
Env knobs (BT_WARP_*) default to the verified values; BT_WARP_SELFTEST/SELFSHOT
are an off-by-default visual-verification harness (backbuffer frame dump).
Docs: new context/translocation-warp.md (geometry/material/visual/lifecycle/env);
reconstruction-gotchas.md gains the accumulated-time precision-collapse bug class;
rendering.md / multiplayer.md / decomp-reference.md / CLAUDE.md cross-linked.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
User report: the shadow broke MID-SESSION -- suddenly solid opaque black and
buried on any slope. The session log pinned the trigger: pressing V. The
view toggle (SetViewInside) RELOADS every segment mesh through the object
loader and swaps them into the render tree -- including blh_tshd.bgf -- and
the reload path never called SetIsShadow(1) (only the original tree-build
call site tagged it). Untagged, the entire shadow pipeline disengages: no
translucent TFACTOR state block (solid black), no depth bias (buried), wrong
pass. The damage-swap reloads had the same hole.
Fix: tag *tshd* filenames in LoadObjectBGF itself, next to the existing
all-shadow-material detector (which misses the mech proxy -- plain black
material, not shadow_mtl). Every load path -- build, damage swap, view
toggle -- now yields a tagged object; the drawOps alphaTest routing reads
the flag downstream. User-verified live: the shadow survives repeated V
toggles, translucent and slope-correct.
This also likely explains the RECURRING "shadow vanishes on inclines"
reports: any V toggle silently broke it; every relaunch "fixed" it. KB
(locomotion.md): loader-level tag recorded as co-dependent part 5 of the
shadow arrangement; the vanish-diagnostic note now lists all three causes
(reload untag / gait desync / genuine burial) with check-first guidance.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
User report: the ground shadow painted OVER the mech's feet. Root cause: the
flat quad + big depth-bias (-0.004 ~= 2-4 world units) workaround for slope
burial -- a bias big enough to beat the TERRAIN also beat the FEET in the
depth test, and the shadow drew in the late alpha-blend pass (after the mech),
so z-arbitration was the only layering control.
Fix, four co-dependent parts (user-verified live: feet on top, opaque,
survives inclines/declines):
- TILT (mech.cpp UpdateShadowJoint): apply the SKL's own contract for
jointshadow ("apply terrain angle to pitch and roll") -- quad up aligned to
the surface normal via an orthonormal basis fed to the ENGINE's own
LinearMatrix->EulerAngles conversion. Hand-derived Euler signs are exactly
how the prior tilt attempts "dug into the hillside"; the engine conversion
is convention-proof. ~35 deg cliff-guard cap.
- SAMPLER (mech4.cpp): surface gradient from the collision probes PLUS
BTVisualGroundLift per probe -- the quad hugs the VISIBLE terrain, whose
lift varies across a slope; world->local rotation by the TRUE yaw from
localToWorld, not the drift-prone gDriveHeading mirror (the task-#48 bug
class). BT_SHADOW_LOG traces the normals.
- DRAW ORDER (new PASS_SHADOW, l4d3d.h/L4VIDRND/L4VIDEO): shadows draw
between the STATIC terrain and the DYNAMIC opaque bodies -- the classic
decal order. The mech, drawn after, z-passes over the shadow: the bias
can never paint the shadow over the feet, structurally.
- BIAS pairing (L4D3D.cpp): tilt on (default) -> decal epsilon -0.0008;
BT_SHADOW_TILT=0 flat fallback -> the old -0.004. BT_SHADOW_BIAS overrides.
KB (locomotion.md): the four-part arrangement recorded as co-dependent, with
the gait-desync-symptom diagnostic hint retained.
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>
