SpaceShooterHealth

The one kill path a 6-DOF space-shooter funnels every death through: destroyShip blows a ship apart — explosion, part detach, shootable debris, respawn — and the aggregate hit-point bucket the HUD bar reads.

What it does

SpaceShooterHealthComponent is pure data: hp / maxHp. For a multi-part ship it is derived — the bullet-impact pass recomputes hp = Parts.totalHp() after every hit, so the aggregate bar tracks per-part damage; the real kill decision is made per-part (a critical part reaching 0), not off this number. For a simple single-box target like floating debris it stands alone. It has no per-frame System of its own; what lives here is the destruction logic every damage source shares.

destroyShip(world, eventBus, ship) is that shared path. It first emits SpaceShooterHealthEvents.EXPLOSION at the ship's pose (the burst-FX origin). Then it forks on who died:

• An enemy sheds its hull. For every still-attached Parts piece it emits wingman.part.destroyed (the renderer detaches that child mesh) and acquires a pooled, still-shootable debris hitbox at the piece's world position — so the wreckage keeps taking fire. Then it emits wingman.enemy.killed (or wingman.freighter.killed for a convoy head, wingman.freighter.car.lost for a cargo car) and removes the ship.
• The player does a respawn-in-place death instead: it emits wingman.player.killed, hides the model (Renderable.visible = false), blows the primitives apart (wingman.player.blownapart), zeroes velocity, stops the guns, tags the ship dead, and attaches a RespawnTimer. No part-detach — there's no re-attach path, so a respawning player would otherwise stay invisible.

A ship already tagged dead is ignored, so a second hit mid-respawn can't double-explode it or reset the timer.

spawnDebrisHitbox(world, …) acquires one slot from the shared debris pool at a shed part's location and seeds a tumbling trajectory that inherits the dead ship's motion. The pool is a Debris blueprint entity in the scene (a Pool marker beside Transform6DOF + Velocity6DOF + SpaceShooterHealth(1) + Lifetime, tagged debris-shootable) — so no impact system registers it by hand; the pool's 1 HP + 6-second clock are re-applied on each acquire.

Use it in a scene

You don't key SpaceShooterHealth on an entity — the death path is imported by the impact components, and ships carry their aggregate HP via ShipLoadout. It becomes part of a scene implicitly: pull any of MachineGun / Missile / Asteroid / OilBlob and this rides along as a dependency. A ship that should be able to die needs Transform6DOF + Parts (and, if it's the player, Renderable + MachineGun) so destroyShip has something to detach and hide.

Events

• Emits wingman.explosion (SpaceShooterHealthEvents.EXPLOSION) at every death — { x, y, z, vx, vy, vz }. The burst-FX origin; the visual is the renderer's job.
• Emits wingman.part.destroyed (PartsEvents.DESTROYED) once per detached enemy piece — { entityId, part, x, y, z, meshSuffixes }. Drives the renderer's child-mesh detach and seeds a debris hitbox.
• Emits wingman.player.killed / wingman.player.blownapart for the player death sequence, and wingman.enemy.killed / wingman.freighter.killed / wingman.freighter.car.lost for the three non-player death classes. MissionDirector, WaveDirector and SpaceShooterScore listen for these.
• Listens for nothing — destroyShip is called imperatively by the impact systems, not driven off the bus.

Dependencies

• Transform6DOF / Velocity6DOF — the ship's pose + motion, read to place the explosion and seed debris trajectories; also the pooled debris entities' own motion.
• Parts — the per-piece hull; destroyShip walks Parts.defs, emits a detach per surviving piece, and spawns a debris hitbox at each.
• Renderable — flipped invisible on the player's death (the one renderer touch).
• MachineGun — the player's guns, silenced (isFiring = false) on death so a dead ship can't keep shooting.
• RespawnTimer — attached to the player on death to drive the respawn-in-place countdown.
• Lifetime — every pooled debris hitbox carries one so wreckage self-expires after 6s.

Notes

• The death event names live in the shared arcade dictionary, not in this component — SpaceShooterHealthEvents sits in @babylonjsmarket/arcade alongside WaypointEvents. Emitters (this) and listeners (MissionDirector / WaveDirector / SpaceShooterScore) both import the names from there, so no listener imports this file (the no-cross-component-event-import contract).
• destroyShip never reads the ship's SpaceShooterHealthComponent. The decision to call it is made upstream (a critical part hit 0, or an instant-kill hazard); this path is purely the consequence of death. The component only travels on the pooled debris, where 1 HP makes each piece a one-shot target.
• removeEntity on an enemy is a real removal; on a pooled attacker (a debris slot, a missile) upstream systems release the slot instead. destroyShip itself only ever removeEntitys the ship that died.