Problems with Biter pathfinding/behavior?

[Olix]

Hi,

I wonder if anyone has noticed problems with the pathfinding and behaviour of Biters in recent versions? I keep seeing them massive bundles of units without actually attacking, like so:



They also seem to build bases much closer to my structures than before:



(drag the images into another tab to see them in full, the forum software crops them)

One base was even built on top of my rail line! there were spawners on either side, and the biters were wandering over the track.

This is all quite annoying because my chosen play style of 'fortified mining outposts connected by unfortified railway' is not viable, and unexpected biter attacks keep destroying my trains and powerlines.

[Xeteth]

Hi,

I wonder if anyone has noticed problems with the pathfinding and behaviour of Biters in recent versions? I keep seeing them massive bundles of units without actually attacking, like so:

These huge clusters have been the way that attacks can occurr for quite a while now, I remember seeing similar sized attacks way back in my 0.11.0 base. I am not sure exactly what determines the size of the group, perhaps someone could science it?

They also seem to build bases much closer to my structures than before:

One base was even built on top of my rail line! there were spawners on either side, and the biters were wandering over the track.

This is all quite annoying because my chosen play style of 'fortified mining outposts connected by unfortified railway' is not viable, and unexpected biter attacks keep destroying my trains and powerlines.

The way that biter bases spawn was changed in version 0.13.0, previously the biters could not spawn a base within 3-4 (can't remember exact number) chunks of a player made entity and led to players 'claiming' huge areas of land which was often called "victory pole-ing". In version 0.13.0 it is now worked off a probability style system whereby the more structures you have the less chance a biter base can spawn nearby, but getting that number right down to 0 requires quite a few structures. You can see this probability in action if you enable "show_enemy_expansion_candidate_chunk_values" in the debug menu.

As for them killing power poles yeah it's a total pain and happens to me quite often. It's to do with groups of biters getting 'stuck' when they try to path past the pole. They then attack the pole because they think they are trapped. I posted this as a bug just yesterday but unfortunately it's not deemed to be a bug and as such it's intended that if you want to 100% protect your rail lines you should turret the entire length. Check here for that discussion: viewtopic.php?f=23&t=31949

[Frightning]

Short answer: Best solution to biters is to minimize the number of biter attacks with maximum prejudice (i.e. clear them out and wall-in what's yours.

[ChurchOrganist]

Whilst on the subject of biters.......

Does the nest spawn rate accelerate as the game progresses?

I was playing on a multiplayer server yesterday, cleared out a load of biter nests, took a break for an hour, and when I came back one had spawned quite close to the rail track I was working on.

I have not noticed them migrating that quickly before. We're currently at 106 hours playing time.

[Olix]

The way that biter bases spawn was changed in version 0.13.0, previously the biters could not spawn a base within 3-4 (can't remember exact number) chunks of a player made entity and led to players 'claiming' huge areas of land which was often called "victory pole-ing". In version 0.13.0 it is now worked off a probability style system whereby the more structures you have the less chance a biter base can spawn nearby, but getting that number right down to 0 requires quite a few structures. You can see this probability in action if you enable "show_enemy_expansion_candidate_chunk_values" in the debug menu.

As for them killing power poles yeah it's a total pain and happens to me quite often. It's to do with groups of biters getting 'stuck' when they try to path past the pole. They then attack the pole because they think they are trapped. I posted this as a bug just yesterday but unfortunately it's not deemed to be a bug and as such it's intended that if you want to 100% protect your rail lines you should turret the entire length. Check here for that discussion: viewtopic.php?f=23&t=31949

Ah, I see. That is a pain. Fully walled train lines are much less satisfying somehow. The problem isn't so much that the power lines are destroyed, but that they can't be rebuilt without manual human intervention. The ghost building site is outside the logistics network, and of course covering the map in a logistics network is no better than fully walling everything.

Whilst on the subject of biters.......

Does the nest spawn rate accelerate as the game progresses?

I was playing on a multiplayer server yesterday, cleared out a load of biter nests, took a break for an hour, and when I came back one had spawned quite close to the rail track I was working on.

I have not noticed them migrating that quickly before. We're currently at 106 hours playing time.

At a guess, I wonder if it is a function of one or more of:

• The number of existing nests
• The size of the revealed map (more revealed chunks = more nests)
• The number of nests effected by pollution

For instance, if every nest has a 1% chance per minute of spawning a party that creates an expansion nest, then as the map grows larger (and more nests are revealed) the rate at which new nests appear would increase.

[Deadly-Bagel]

Theoretically destroying power poles shouldn't be a problem until they're attacking in large waves, which is fairly late game. Also for spawning on your rails, not personally had this problem (perhaps because I also put two lights next to each power pole?) though they've spawned close enough to aggro me as I pass on a train.

Waaay before Behemoth biters spawned (actually... I'm not sure I've even ever seen one =s) I set up a huge wall covering nearly all my outposts with the intent of building huge solar farms. Can clear out the nests within and then as long as you have fairly good coverage they can't spawn inside. They will try to migrate but die on the wall. Late game the only problem that should hold you back from doing this is it's damn tedious.

[Olix]

I made a mod that turns trains and big power lines invincible:

https://mods.factorio.com/mods/Olix/inv ... -and-power

This makes the game more fun for me as I don't have to babysit and manually replace my trains, or genocide all the biters everywhere.