Fix coop double-spawn of chrysalid from convertUnit packet race#10
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NonPolynomialTim wants to merge 1 commit into
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Fix coop double-spawn of chrysalid from convertUnit packet race#10NonPolynomialTim wants to merge 1 commit into
NonPolynomialTim wants to merge 1 commit into
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In co-op both the convertUnit network-packet handler and the local coop-death UnitDieBState call SavedBattleGame::convertUnit for the same dying zombie. The respawn-only-once guard lived only at the callers, so when the local death state won the race the unguarded packet handler spawned a second chrysalid on the observing player. That extra unit never received a death packet, stood frozen for the rest of the mission, and desynced subsequent unit IDs. Enforce the already-respawned guard inside convertUnit itself so the loser of the race is a no-op. Callers already null-check or ignore the return. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Summary: Fixes a co-op bug where killing a chrysalid-spawning zombie and its resulting chrysalid in the same auto-shot leaves a frozen, immortal chrysalid on the observing player's screen for the rest of the mission.
Root cause: Both the convertUnit network-packet handler (connectionTCP.cpp) and the local coop-death UnitDieBState::think() call SavedBattleGame::convertUnit for the same dying zombie. The respawn-only-once guard lived only at the callers; the packet handler was unguarded. When the local death state wins the race, the packet handler spawns a second chrysalid that never receives a death packet — it stands frozen and desyncs subsequent unit IDs. Timing-dependent, hence the same-auto-shot trigger.
Fix: Enforce the guard inside SavedBattleGame::convertUnit (the chokepoint both paths share); the race loser becomes a no-op (return nullptr). Callers already null-check or ignore the return.
Validated manually in 2-player co-op; both units now die correctly on both screens.