(b) The 'tiny explosion' on the ram kill is AUTHORED: crunch res 31 = 'stephit'
(one video object, effect 1008 = ddam5 damage smoke) -- a step/ram squash is
small by design. The FULL explosion res 32 = 'trkdead' = psfx 15 dtrkboom
(fiery omni burst) + psfx 16 dtrkburn (the burning-wreck fire), reached by
WEAPON kills -- which the 1995 binary dispatches [T1]:
- MechWeapon::SendDamageMessage @004b9728 (part_013.c:6765) gates only
"target NOT derived from Mech@0x50bdb4 OR aimed zone set": a non-Mech
boresight target takes the zone=-1 damage UNCONDITIONALLY;
- Missile contact @004be078 dispatches at the struck solid's OWNER entity
with no class test at all.
Port wiring: Mech::WorldStructurePick returns the struck solid's owning entity
(BoxedSolid::GetOwningSimulation; TERRAIN.cpp:107/246 build every static solid
with its Terrain/CulturalIcon/Door entity as owner); the mech4 pick block
designates IT instead of the gBTTerrainEntity sentinel (sentinel = fallback);
the projectile contact path grew the non-mech damage-zoned else-branch
(@004be078 mirror, direct Dispatch). Plain terrain ignores the damage
(ENTITY.cpp:885 zone==-1 guard); an icon's handler maps -1 -> 0 and dies.
Truck armor is WeaponDamagePoints=1 (TRK.DMG): one laser = one dead truck.
(c) The burning fire is dtrkburn.pfx, authored INTO the death package (every
icon family carries 1016: trkdead/bigdead/meddead/msldead/twrdead). There is
NO looping BurningState fire in the binary: the damage-zone effect watcher
ctor @0042a984 has exactly one call site (the Mech ctor, part_012.c:10405), so
icon ExplosionTables are inert, and CulturalIcon has no Performance.
Documented as authentic -- nothing invented.
Verified live (BT_SHOT pixel capture): 26 laser kills, [cult] TakeDamage
type=3 -> DYING res=32 -> DPLIndependantEffect 1015+1016 at the icon origin;
frames show the orange dtrkboom fireball, dtrkburn flames on the fresh wreck,
and the rubble aftermath; ram harness re-run still fires crunch res 31.
Diags: BT_FIRE_AT_ICON (designate nearest ahead icon; live-icon census in
CULTURAL.cpp), BT_FX_TEST="1015,1016".
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Playtest report: trucks play a collision sound on impact but never change
state -- no explosion swap, no destroyed model, collision volume persists.
Investigation (BT_CULT_LOG census + BT_GOTO ram harness): the SIM was never
broken. ARENA1 map-streams 124 CulturalIcon entities, each with a damage
zone, explosion resource and removeOnDeath; the mech crunch dispatch
(ProcessCollision -> BTDispatchCollisionDamage) reaches them; ~19 walking
bumps burn the zone -> CulturalIcon::TakeDamageMessageHandler spawns the
Explosion (psfx effect 1008 observed), posts the delayed BurningState and
deletes the collision boxes. All of that ran correctly and invisibly.
The ACTUAL bug: the 2007 WinTesla port fully stubbed
StateInstanceSwitchRenderable ('STUBBED: DPL RB 1/14/07') -- ctor never
registered on the state dial, Execute never toggled anything -- so the
intact->rubble visual swap on BurningState NEVER fired, for every cultural
icon in the game. The destroyed truck kept its intact model: exactly the
reported 'no state change'.
Revival (D3D9-native, 1995 semantics verbatim):
- StateInstanceSwitchRenderable now controls the draw COMPONENT via the
SetDrawObj in-place drawable swap (the mech RemakeEntity mechanism):
visible = captured d3d_OBJECT, hidden = NULL. Initial state in the ctor,
AddVideoWatcher on the SimulationState dial (SetState fires video
watchers), toggle only on a real change.
- L4VIDEO cultural case passes the draw component + object (the dead
dpl_INSTANCE param is gone); [video] Object hides at BurningState,
Rubble shows.
- REQUIRED: cultural objects stay OUT of static-mesh consolidation
(RecurseStaticObject, same exclusion class as banded LODs/shadows) --
a merged static draws forever regardless of DrawObj.
- Permanent env diag BT_CULT_LOG: creation census (zones/explosion/flags/
pos), TakeDamage trace, death transition, [cultvis] switch actions.
Verified live (BT_GOTO=-620,-328 ram, ARENA1): 19 crunches -> DYING ->
explosion 1008 at the icon -> [cultvis] HIDE x2 (intact) + SHOW (rubble)
-> contacts cease, mech walks into the former footprint. Boot + render
un-regressed (statics consolidate as before minus the 124 icons).
KB: context/rendering.md new section (the full chain + the consolidation
gotcha). MP replicant path shares the same SetState watcher (cross-pod
verification pending -- noted in the issue).
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>