#89 DEATH BLAST reconstructed: a dying mech splashes its neighborhood

The missing half of Advanced Damage, found by call-scanning
Explosion::SplashDamage @0042fad0: TWO callers, not one -- Missile::Perform
(the known #62 path) and 0x4a0bda, the UN-EXPORTED tail of
Mech::TakeDamageMessageHandler itself.  Raw disasm @0x4a07b8-0x4a0bda:
when the victim ENTERS dead(9)/eject(10) during the applications, the
binary sets the wreck burning (id 0x17, deferred -- handler not yet
reconstructed), spawns the death Explosion (model 0x31 -- our death-list
visuals stand in), and SPLASHES:
  gates : owning player's advancedDamageOn (+0x264) AND NOT
          suppressConsole (+0x258 -- eject sets it: PUNCH-OUTS NEVER
          BLAST, the authentic anti-suicide-bomb rule)
  damage: type 2 Explosive, amount = deathSplashDamage (mech+0x520),
          bursts = round(0.001 * moverMass * 15.0) -- scales with tonnage
  radius: deathSplashRadius (mech+0x524); per-victim falloff
          bursts/dist^1.25 in the shared core
Draco's collision-divert suspicion is settled: the blast is TYPE 2, the
divert never touched it -- the tail was simply never reconstructed.

Port: deathSplashDamage/Radius PROMOTED from the Wword scratch bank to
named Mech members (the bank is one GLOBAL array -- authored per-chassis
values were clobbered to the last-loaded mech); BTSplashCore split out of
the #62 weapon splash and shared; BTApplyDeathSplash + the death-edge arm
in the handler tail; BTPlayerConsoleSuppressed bridge (friend).

Bench (2-node, B parked 8.9u from a self-destructing A): blast fired with
authored madcat data (radius=50, amount=5, mass=75000 -> 1125 base
bursts), B took 73 bursts (falloff exact: 1125/8.91^1.25), cross-pod
delivery + cylinder spray verified on B's own log ([dmghit] type=2
burst=73 across zones).  ~365 damage at 9u -- Draco's 'double kills on
drops' economy restored.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

game/reconstructed/mech4.cpp

@@ -1235,6 +1235,10 @@ static Scalar
 	return radius;
 }
 
+static void
+	BTSplashCore(Entity *shooter, const Point3D &center, Entity *directVictim,
+		const Damage &dmgTemplate, Scalar radius);		// #89 shared core (below)
+
 void
 	BTApplySplashDamage(Entity *shooter, int weapon_subsys, const Point3D &center,
 						Entity *directVictim, const Damage &dmgTemplate)
@@ -1246,7 +1250,18 @@ void
 			<< " radius=" << radius << "\n" << std::flush;
 	if (radius <= 0.0f)
 		return;										// this weapon authors no splash
+	BTSplashCore(shooter, center, directVictim, dmgTemplate, radius);
+}
 
+//
+// #89: the splash CORE, shared by the weapon-detonation caller above and the
+// DEATH BLAST below (the binary's two Explosion::SplashDamage call sites).
+//
+static void
+	BTSplashCore(Entity *shooter, const Point3D &center, Entity *directVictim,
+		const Damage &dmgTemplate, Scalar radius)
+{
+	static const int s_log = getenv("BT_SPLASH_LOG") ? 1 : 0;
 	extern int BTIsRegisteredMech(Entity *e);
 	extern int BTGetTargetCandidates(Entity *shooter, Entity **out, int maxOut);
 	Entity *cand[32];
@@ -1322,6 +1337,71 @@ void
 	}
 }
 
+//
+// #89 DEATH BLAST -- the second authentic SplashDamage call site (raw disasm
+// @0x4a07b8-0x4a0bda, the un-exported TakeDamage tail; provenance banner at
+// the caller, mech.cpp).  A dying mech's explosion damages every mech inside
+// its authored DeathSplashRadius:
+//   gates  : owning player's advancedDamageOn (+0x264)  AND
+//            NOT suppressConsole (+0x258 -- eject sets it: punch-outs never
+//            blast) [T1 @0x4a0aa8-0x4a0ad6]
+//   damage : type 2 Explosive [T1 @0x4a0aef], amount = deathSplashDamage
+//            (mech+0x520, authored "DeathSplashDamage"), impact = mech origin
+//   bursts : round(0.001 * moverMass(+0x20c) * 15.0) [T1 @0x4a0b21-0x4a0b33]
+//            -- the blast scales with the chassis mass; the per-victim
+//            falloff (bursts/dist^1.25) applies in the core
+//   radius : deathSplashRadius (mech+0x524, authored "DeathSplashRadius")
+//   excluded: the dying mech itself (the binary's Explosion anchors on it;
+//            the core's candidate walk already excludes the shooter)
+//
+void BTApplyDeathSplash(void *mech_v)
+{
+	Mech *m = (Mech *)mech_v;
+	static const int s_log = getenv("BT_SPLASH_LOG") ? 1 : 0;
+	if (m == 0)
+		return;
+	extern int BTPlayerAdvancedDamageOn(void *player_v);
+	extern int BTPlayerConsoleSuppressed(void *player_v);
+	void *player = m->GetPlayerLink();
+	if (player == 0)
+	{
+		// binary derefs mech+0x190 unguarded (every arcade mech had an owner);
+		// the port's link-less solo dummy skips, loudly under the log.
+		if (s_log)
+			DEBUG_STREAM << "[splash] DEATH: no player link, skipped\n" << std::flush;
+		return;
+	}
+	if (!BTPlayerAdvancedDamageOn(player) || BTPlayerConsoleSuppressed(player))
+	{
+		if (s_log)
+			DEBUG_STREAM << "[splash] DEATH: gated (advDmg="
+				<< BTPlayerAdvancedDamageOn(player)
+				<< " suppress=" << BTPlayerConsoleSuppressed(player)
+				<< ")\n" << std::flush;
+		return;
+	}
+	if (!(m->deathSplashRadius > 0.0f))
+		return;										// chassis authors no blast
+
+	Damage dmg;										// Damage::Damage @0x41db7c
+	dmg.damageType   = (Enumeration)2;				// Explosive
+	dmg.damageAmount = m->deathSplashDamage;
+	dmg.impactPoint  = m->localOrigin.linearPosition;
+	int bursts = (int)(0.5f + 0.001f * (float)m->moverMass * 15.0f);
+	if (bursts < 1) bursts = 1;
+	dmg.burstCount = bursts;
+
+	if (s_log)
+		DEBUG_STREAM << "[splash] DEATH BLAST mech=" << m->GetEntityID()
+			<< " radius=" << (float)m->deathSplashRadius
+			<< " amount=" << (float)m->deathSplashDamage
+			<< " bursts=" << bursts
+			<< " (mass=" << (float)m->moverMass << ")\n" << std::flush;
+
+	BTSplashCore((Entity *)m, m->localOrigin.linearPosition, (Entity *)m,
+		dmg, m->deathSplashRadius);
+}
+
 // Called from ProjectileWeapon / MissileLauncher::FireWeapon (via the extern below)
 // with the live muzzle, the SHOOTER mech (to resolve the real launch port), the owner's
 // locked target entity + point, the launch speed (|muzzleVelocity|), and per-shot damage.