The Wonders of AI in Half-Life
I’ve played many shooters over the years, some where the AI is great, others where it isn’t that smart, but does a great job for the game you are playing. Of course, there are others where the AI is dull, and brings the game down. The twenty year-old Half-Life though, still stands out as one of the best implementations of AI in a shooter.
Why am I musing on the nature of AI in a twenty year old game, just a couple of days before we enter 2019? You can blame Simon Roth for that. Last night he released a ten minute video diving into the AI of Half-Life and explaining how Valve manged to create such a believable foe in the Marines.
It helps that Simon is a developer, and knows what he is talking about when it comes to this kind of thing. He is, of course, the one-man developer of colony management game Maia, released back in November.
Having these AI routines explained in such simple terms makes me wonder why the AI in a game like Battlefield V can feel so scripted, with anything off script leading to chaos. Even things like the detection of the player comes across in a much more realistic manner in Half-Life than in EAs behemoth.
It might, of course, come down to how the games are portrayed to you. Valve’s seminal masterpiece is a straight-up shooter, stealth (apart from in the Blast Pit) isn’t really something you have to think about. But even then, you know that if you are quiet, and don’t get into the sightline of the Marines, you can make pretty decent progress through an area.
Battlefield on the otherhand sets up levels where it feels like the developers consider stealth to be the “right” way of playing. Be that through warnings from friendly characters, or the optional achievements that are set in each mission. By setting up levels in this fashion, you naturally tailor your approach to be as stealthy as possible.
The trouble is, the nature of the game isn’t setup for a stealthy approach. In classics like Thief or the modern Dishonored games, they are nuances in the UI which give you clarity over whether you are likely to be spotted, or heard. This doesn’t exist in Battlefield V, which leads to situations where you can be crawling through grass on a rise, with no previous enemies alerted, when suddenly a patrolling enemy on the lower ground will spot you.
It leads to situations where you give up on taking a stealthy approach, and resort to a classic run-and-gun approach. Even then, the AI doesn’t feel like it is behaving in a realistic manner. Cover won’t be taken when it is best to do so, and foolhardy charges straight towards you are a regular sight. Compare this to the Marines in Half-Life who intelligently take cover and regroup with squadmates when sensbile.
There can be good AI in games, I just wonder whether after twenty years, we should be seeing generational leaps forward?