Pre-placed Black Eagle on neutral airfield stuck in post-mortem state when killed

[Metadorius]

Description

Phobos Version

0.4

Conditions to reproduce

CnCNet YR 9.x.x

INI code

see map

Steps to reproduce

1. Download repro map.zip and unpack into CnCNet YR maps/Custom to play.
2. Kill the Black Eagle on the neutral airfield, with or without capturing it.

Expected behaviour

Black Eagle should die

Actual behaviour

Black Eagle is stuck in post-mortem state

Additional context

Video of the bug repro (timecoded) https://youtu.be/kkUO5pv1NLI?t=2281

Checklist

• The issue happens on the latest official version of Phobos and wasn't fixed yet.
• I agree to elaborate the details if requested and provide thorough testing if the bugfix is implemented.
• I added a very descriptive title to this issue.
• I used the GitHub search and read the issue list to find a similar issue and didn't find it.
• I have attached as much information as possible (screenshots, gifs, videos, debug and exception logs, etc).

[Metadorius]

Can anyone of @Phobos-developers/t1-maintainers check the issue and try to fix it?

[Starkku]

The immediate reason this happens is because of this hook in Hook.Bugfixes.cpp

DEFINE_HOOK(0x4D7431, FootClass_ReceiveDamage_DyingFix, 0x5)
{
	GET(FootClass*, pThis, ESI);
	GET(const DamageState, result, EAX);

	if (result != DamageState::PostMortem && (pThis->IsSinking || (!pThis->IsAttackedByLocomotor && pThis->IsCrashing)))
		R->EAX(DamageState::PostMortem);

	return 0;
}

Which overrides TechnoClass::ReceiveDamage() result to PostMortem if the specified conditions are in effect. The thing that leads to this is IsCrashing being set to true.

IsCrashing is true because AircraftClass::EnterIdleMode() (which in itself is called as early as TechnoClass::Unlimbo()) calls FootClass::Crash() if AirportBound=true aircraft cannot find a dock. Preplaced AircraftTypes are created before buildings so there will be no docks available for them initially, and it doesn't look like IsCrashing is reset at any point when the docks become available either.

Unsure what the best approach to fix this issue would be, it is technically INI parsing order problem but I guess it only produces visible issues (unless?) with that Phobos hook present.

This could also be fixed on the mapper's side by spawning the aircraft in via triggers.

[Metadorius]

I've been told that my bug report is a bit incorrect (?), the AircraftType flies from across the map and is not present. I haven't verified it.

Is it possible to look up all aircraft when the free dock appears and set IsCrashing to false or something?

[Starkku]

When I tested the map the Black Eagle was on the airpad and was immortal as presented in the initial bug report.

That is a possible solution I suppose, it can be restricted to pre-placed docks only as well.

[Starkku]

This should be fixed in 903c369