MechWeapon::UpdateTargeting computed effectiveRange = (1 - heatLoad) * weaponRange,
reading the weapon's own inherited HeatableSubsystem heatLoad. The authentic decomp
(@004b9bdc:6983) reads *(weapon+0xE0)+0x158 = Subsystem::damageZone->damageLevel --
i.e. effectiveRange = (1 - HOST-ZONE DAMAGE) * weaponRange. Same @0xE0-DamageZone-vs-
heat misattribution already corrected in HeatSink::UpdateCoolant (heat.cpp:803).
Impact: for a charge/discharge weapon (ER laser) the weapon's OWN heatLoad swings
0..1 every fire cycle, so effectiveRange collapsed toward 0 and the weapon was
perpetually "out of range" -> Emitter::FireWeapon's `if (dist <= effectiveRange)`
gate skipped SendDamageMessage -> NO damage submission and hence NO impact explosion.
The beam still rendered (beamFlag/beamEndpoint set before the gate), so the shot LOOKED
like a hit but did nothing -- the user-reported "lackluster/absent laser hits, esp.
the ER medium, on mechs AND buildings". PPCs mostly worked only because their heatLoad
happened to sit low/stable.
Fix: read the QUALIFIED this->Subsystem::damageZone->damageLevel (the MechSubsystem
shadow is a shim -- heat.cpp:812) so an UNDAMAGED weapon holds its full, STABLE
weaponRange, and range shortens only as the weapon's host zone takes battle damage.
Verified (parked in range of a building, autofire): laser effRange 500 STABLE
(was fluctuating 0/59/340/424 -> mostly out of range); impact explosions 13 in 22s
(11 laser id=16 + 2 PPC), up from ~2. Lasers now consistently damage + spawn FX.
Also adds env-gated diagnostics used to root-cause this: [fireW] range trace +
per-weapon explID (emitter.cpp), and BT_FIRE_AT_STRUCT (mech4.cpp) which designates
the nearest world structure so weapon-vs-structure fire can be tested without the
screen aim ray.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
