[Zandronum-latest]Projectiles with +SHOOTABLE can die twice

[Edward-san]

Bug report.

Projectiles which got this flag and have some delay before explosion(A_Explode in my case) can die twice. When hit the wall they enter their Death state and then explode but damaging themselves die again. And what is most important they explode again! This bug could be avoided(and is avoided in my case) placing A_UnsetShootable in Death state. Howewer this is not intuitive.
A way to solve it is making projectiles become unshootable as they enter Death state automatically.

Attached wad.

Is it intended behaviour?

[Gez]

Meh.

This bug could be avoided(and is avoided in my case) placing A_UnsetShootable in Death state. Howewer this is not intuitive.

Shootable projectiles are not intuitive either. The Doom engine was never designed with the idea that projectiles can be shot. They use their Death state, but they are directly sent to it when they impact, instead of being sent to it by being explicitly killed. (They keep all their hit points.)

Also, I see this as no different from having to use A_Fall (or A_NoBlocking) in the death state sequence of a monster.

[NeuralStunner]

You can also begin the death state with [wiki]A_Die[/wiki]. If it "died"by impact it'll immediately "re-die" bay damage. If it "died" by damage, it can't "re-die" so it'll proceed.

Code: Select all

Death:
	BOOM A 0 A_Die
	BOOM A 4 A_Explode
	BOOM BCD 4
	

In that case I'm not sure the engine needs an override, likely wouldn't be difficult but it's simple enough on the modder's side too.

[Xaser]

Doesn't A_Die immediately jump to Death? That looks infinte-loop-y to me, unless it's got a special check to never re-die.

[NeuralStunner]

If the thing is already health-dead, the function does nothing. It's fine.

[randi]

Mehh, might as well. Changed in r3827.

[DoomRater]

Aha, that DOES explain why the Duke pipebombs were shootable on the ground before but not now. Now that I know this is now the intentional behavior, I can make sure upon normal death that shootable is re-enabled.

One question though- does this activate when a projectile bounces off a wall as well? If so I might actually ask if it can be reverted...

[Guest]

Only if they "die" when they hit the wall.

[DoomRater]

That's fine, the code for pipebombs only needs to set shootable again when they reach that point and reset when forcibly blown up by shot or when told to detonate. Twas funny getting stuffed throwing pipebombs at Hexen monsters and having them blow up in my face!