[v1.05 - GC] Passive Command Room Aliens

[kabill]

I've been getting a fairly serious issue with command room aliens, which is that they frequently do nothing other than move around. I've uploaded a video to demonstrate the problem; the relevant section begins at 4:20

[video=youtube;231T-QE8o_8]

The Command Room aliens more or less only move around. When the soldier moves into the command room at the beginning of the video, there's an alien that could easily attack and kill him. Instead it only moves across from one side of the room to the other, where it stays until it is killed without taking a shot.

The aliens in the back engine room do the same. They continually shuffle around the room, but do not ever fire. At one point - when I go back to pick up the plasma rifle - I even leave my soldier entirely out of cover (I check this on my turn by tracing LoF to the alien; the path is clear) yet it does not take a shot. Eventually, right at the end of the video, the alien shoots at my soldier, but almost as an after-thought: it's clear that it moves somewhere else first, then moves into position to shoot.

I've seen this in many missions now since at least v1.0 but I wasn't sure whether it was other things like using smoke or cover which were simply stopping the aliens from shooting due to the minimum hit chance. This doesn't seem to be the case here, however, because even if it was there is plenty of opportunity for the aliens to advance to kill my singular remaining soldier in this video.

For what it's worth, I've seen behaviour similar to this with aliens other than the Command ones, although not with any consistency.

I should add that when I recorded this video, I'd implemented some AI tweaks to the Command and Defensive alien types. However, on the most part the defensive aliens weren't doing the same thing, and I subsequently checked using the vanilla AI values and exactly the same thing happened. The only other mod that I'm running is Fire in the Hole, which shouldn't be affecting alien behaviour unless it's related to the UFO layout (but, as I've said, I've seen this behaviour elsewhere as well).

I appreciate that it might be late in the day for fixing this, but I wanted to highlight it in case there's any chance of resolving the problem.

[kabill]

In case it looks like it might have anything to do with the specific layout/context, I've got a video showing the issue in a different circumstance if that would be helpful.

[Gijs-Jan]

Uploading a save is the best way you can help me, speeding up the process immensely. So if you can, please upload it

[kabill]

I'll see if I can get something uploaded this evening. For what it's worth, you might be able to get this yourself simply by loading a mission with aliens with the Command AI script, as it seemed to be happening pretty consistently with them for me.

[kabill]

Right, here's some saves

Bear with me, as it's going to need some explaining.

Saves 1, 2 and 3 are in a vanilla scout. There's two sebillians in the engine room at the back. If you leave the soldier out in the open, they get shot at as you'd expect, and there doesn't appear to be anywhere you can hide in the engine room which stops that.

However, if you leave the doors open and go and hide behind the data core in the main room, the aliens will mill around in the engine room in spite of having LoS and refuse to do anything. They don't leave the room, they just move around.

(I can't remember which of the saves have what set up exactly, but you can try this out yourself if nothing else using the first one for sure.

Saves 21, 22, 23 and 24 are from a modded landing ship (apologies that it's modded; I forgot to remove my UFO maps. I'm fairly certain you should be able to load it, though, as everything else is vanilla and the map data should be saved with the save game, yes?)

21 has an alien outside the command room. I've had that alien both advance towards my soldier and retreat away from them to hide.

22 has two aliens in the command room, one close by in front, the other to the soldier's right further away. If you end turn, both aliens will shoot.

23 is the same as 22, but I've killed one of the aliens and moved into cover against the other. The remaining alien will typically wander back and forth doing nothing. Sometimes, it apparently activates "kill mode" and moves forward to attack. Interestingly, if you move away from the alien when it does this, it seems to move back into a passive wandering around stance.

I can't remember what 24 is, but I think it's like 23 but in different positions.

Saves 31, 32 and 33 are another landing ship, again with Androns. All saves are in the command room, with various numbers of dead aliens as the saves progress. However, no matter what I've done, the remaining aliens always move forwards to attack, as you'd expect.

I'm really not sure what to make of this, myself. Hopefully these are useful. (And sorry for their messiness).

EDIT: I've just updated the link with a couple more saves borrowed from something someone else uploaded.

Again, landing ship (this time vanilla). Caesans; command room. The aliens shoot as would be expected (save 41). Deploying smoke (save 42) stops them from shooting, and they resume afterwards.

I assume this is intended behavior to do with the minimum shot chance variable, but I thought it worth including anyway.

I'm wondering whether the minimum shot chance has something to do with it. From the testing I was doing to produce these saves, the issue only seemed to come up when there was cover involved, when sometimes the AI doesn't seem to be able to react effectively and just wanders round rather than either holding (for reaction fire) or advancing for a better shot. So it might simply be a matter of getting the AI to deal a bit better with low hit chances.

That said, from what I can tell Androns have higher hit chances than Caesans and while I've not seen Caesans refuse to shoot (other than in the example with smoke above) I have seen Androns refuse. This shouldn't be down to different thresholds, as by my understanding the hit chance for Command AI should override their individual race/class AI (unless the override isn't working).

Edited June 16, 2014 by kabill

[RavenX]

This might be a dumb question, but are they effected by morale or panic in any way? Or is that not taken into account for the aliens? Keep in mind I haven't even looked at the alien AI code nor would I even understand much of it aside from changing some values. Was just a thought as I seem to recall being able to panic the aliens or messing with their morale by killing them quickly back in OG X-Com days. Then again I might be thinking of one of the many X-Clones I've played over the years.

[kabill]

There's no panic effect that I know of. Certainly not using the same system as for the player, as I know that was cut. I guess it's possible that there's something in the AI scripts which mimics it, but I actually tested this in saves 31-34 by incrementally killing off the remaining aliens on the same turn (and it made no difference).