Years after the Borealis Incident, the remaining rebel fighters struggle to find a hero to replace Gordon Freeman. Running low on options, they resort to creating one of their own. An original story set in the Half-Life 2 universe. Re worked weapons, enemies, and even suit functions make for a totally new way to experience the world of Half-Life 2.

Report RSS The AI design of Inhuman

One of the biggest priorities of this mod since day 1 has been improving how npc's in Half Life 2 act in combat. Soldiers are smarter, hunters are more capable and more mobile than ever, and even metropolice are getting some improvements to their ai!

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So after a long bout of silence I'm back with an article for you guys. I know it's been some time but I can say it has not gone to waste. Much work has been done overhauling enemy ai and refining the mod and I'm now locking down what levels are going to make it to release. It's gonna be a bit before I have pretty media to share with you guys so I'd like to talk about what makes these npc's really different from what you get in Half Life 2. Before I get into all of this though, I'd like to give my man Joe Wintergreen a shout out for his great video on HL2's ai and its problems:

Combine Soldiers:
One can basically break down a soldier's thought process like this: Can I shoot my enemy, can I throw a grenade at him, do I need to path to get line of sight on him, am I out of ammo? This might cover the basics, but there are huge holes in this. They have basically no ability to position themselves relative to the player beyond "find a spot where I can shoot him from". There's no flanking, they always run, and it's not that uncommon for them to run to the player with low ammo, fire a few shots and then realize they're out causing them to awkwardly run away again to reload. So my mod's big goal with them is to address these issues and add a lot more fun nuances!
One of the big differences with Inhuman's Combine is the amount of options they have to choose from before they actually go directly to you. If you've just gone into cover, instead of pathing to you they might wait a bit while their squadmates path to line of sight not on you but where you were last seen. They might also walk to a cover position with their gun pointed at your last seen position, or choose a flanking position, again relative to your last SEEN position. This distinction allows for them to hold advantageous positions longer and group up instead of charging single file into a camping player with a shotgun. It also gives the player incentives to move around. You're often better off finding a better spot in a side route than waiting for them to go after you!

Another big issue I wanted to address with soldiers is making their tactics stand out more, as in showing the intention behind an action which makes them seem more deliberate and thus smarter. Combine soldiers, unlike the HECU, can move and shoot. While this might make them a more effective enemy, the problem is it leads to them always facing you as they run, making it appear like they're always doing the same general tactics. HECU on the other hand, actually have to face their goal. If they run from you, they're fully committing to it by facing away and running for it. So I've replicated this by having retreating soldiers no longer aim at the player. Another way to help make their decisions stand out while also changing up the feel of fire fights is a slight but important change to how they choose to throw grenades. In the past, soldiers would actually cheat a bit and see if a grenade could even hit the player when they throw it to flush him out. Now, if a soldier loses sight of a player and has a chance to toss a grenade at his last seen position, he'll chuck that grenade right in even if it might not directly hurt you. These two changes allow them to look a lot more deliberate in their actions and hopefully should make them feel a lot more fun and menacing to go up against!

(Side note, a lot of these changes are also rolled over to the Metropolice, making them much more capable than their original incredibly simple HL2 version.

Hunters:
Hunters are one of my favorite enemies in Half Life 2 and have really captured my imagination since the instant I saw them. However, there was always one big disappointment I had with them, and that's the fact that they can't actually jump! They're allowed to jump down in a few really specific scenes and have some scripted jumping animations but is not part of their navigation at all. So to fix that, with some simple tweaks, hunters are now capable of jumping around the map as they please! On top of this, they're actually capable of looking for "advantage points" a cut concept for the combine assassin which allows them to check if they can take the high ground when attempting to get line of sight on the player. Thanks to this new behavior and a lack of gravity gun to stun lock them with, fights with hunters will force a lot more movement out of the player as the hunters constantly reposition for new opportunities to fire flechettes down on them.

Vortigaunt Slaves:
One of the new, well new to Half Life 2 anyway, additions Inhuman makes to the enemy roster is the inclusion of Combine controlled Vortigaunt slaves. Their behavior has been done completely from scratch and while still a bit WIP, I'm fairly happy with them as they are. Vortigaunts in some ways borrow some ideas from the new soldier ai, trying to flank the player and using a new projectile attack to flush enemies out when they've lost sight of them. They will stick use their classic zap attack players have been used to for years, but their new abilities will make them a far different beast than what you face in HL1 or Black Mesa.

I don't have a demo I'm happy enough with to show off, but you can see a lot of what I'm talking about in this older video:



Stay tuned for more updates within the coming months. More and more content is getting locked down for release so a lot of maps I'd previously not show due to how visually unpolished they are will be a lot more presentable soon enough. My philosophy has been to figure out the gameplay above all else which has its pros and cons. The pros are that I've been able to test what actually works with this new ai system and gotten a lot better at mapping in general. The downside is most of what I've done looks incredibly unfinished, hence the lack of media updates. Rest assured though that this mod is alive and kicking and I'm expecting this year to be a great one for it!

(P.S If you'd like to see more bits and pieces of media though be sure to follow my youtube channel where I post things a little more regularly.)

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naryanrobinson
naryanrobinson - - 634 comments

I always thought the combat in Half-Life 2 was a clumsy, miserable affair...

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Cvoxalury
Cvoxalury - - 1,287 comments

Did you really, are you jumping on this recently developed bandwagon? Because weirdly enough, HL2 combat and AI is pretty alright but in these few recent years it's become so common to call it bad.

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naryanrobinson
naryanrobinson - - 634 comments

I wrote this in 2006:
Unlike the original, the combat has no rhythm. It's nothing like the dance of death which you hear about in games like Doom. It's just not very satisfying to play.
The pistol is too weak to be of general use outside of the first few minutes,
the revolver is powerful enough and fast enough (without BTT), but you're always using it when being shot at, jerking your screen around, so you can never aim it properly.
the SMG is useless unless at close range, and uses ammo too fast,
the pulse rifle is arguably the only really useful weapon in the game, but its cool alt-fire is almost always less practical than just mowing them down, leaving a very boring weapon,
the shotgun is useful only with the double shot, but then you've only got 3 shots, and takes forever to reload,
the grenades are awkward as hell to use and take too long to explode meaning you always miss,
the rocket launcher is obviously only supposed to be used with gunships, and again only has 3 shots,
the crossbow is for long-range, but at long range your target has moved a *lot* since you fired the bolt, making it only useful as another close-range weapon, but if you miss your shot you're dead.

You always end up with dumb, bullet-sponge guys right up in your face unloading on you.
I really hate the combat in Half-Life 2. Like I said, it's never satisfying.

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NOMADs_Reviews
NOMADs_Reviews - - 179 comments

Exactly what HL2 needs :-)

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BigTinz
BigTinz - - 1,532 comments

Wow. This looks really impressive. Especially that double hunter fight.

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Dune_Jumper
Dune_Jumper - - 1,586 comments

The new AI looks really cool! And the article provides some interesting insights as to why HL2 combat feels so ******.

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Cvoxalury
Cvoxalury - - 1,287 comments

Except it's not ****** and never has been. I bet you have little idea what you're talking about.

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TheRenegadist
TheRenegadist - - 2,087 comments

Oh wow, didn't know you made a channel for this until the article popped on my feed. Definitely tracking this.

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Zorro_de_la_noche
Zorro_de_la_noche - - 562 comments

Awesome.

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wilsonC
wilsonC - - 106 comments

By the way, you can add suppressive fire to the combine (with basically no perf impact) by copying episodic Alyx's firing code, (there's a bit where they spawn a temp bullseye at a dead enemy's location so she shoots at dead bodies a bit), just paste this into the part of the combine AI where they lose sight of their enemy. This makes them look way smarter as they fire on your position as they move to flank you. I don't have the HL2 code anymore but if you need help, I could download it and look up the line numbers for you :)

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ComfortJones Author
ComfortJones - - 95 comments

Interesting idea. I might look into this.

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