suggestions: subsurface + subways could solve spidertron not travelling between surfaces, and add many other logistics options

[angrypidgeon123]

modmashsplinterunderground_1.1.43 does subways but with trains only. Haven't tested it myself yet

I think underground is a niche area just like Space Exploration for space, Cargo ships for sea. Has lots of potential since the whole base can be moved underground for protection from CME, meteors and enemies. Tunneling logistics under water bodies and other obstacles, and for clearing lanes throughout the base.

Maybe surface resource spots can be mirrored underground too as a way to safely tap the vein without bothering with the enemies. Pollution could be handled differently such as if it accumulate it should damage the machines beyond a certain value, so it should be either vented to the surface with the existing building, or handled with existing air filtering mods. With vanilla pollution it doesn't matter where it is generated to cause evolution (or maybe not on same surface cancels evolution, I don't know), however I'm using a mod which makes evolution happen naturally when it hits the enemy

Speaking of which, tunneling from underground to the surface is needed, also setting the vent from underground etc.

With item and fluid delivery buildings already underground logistics and surface logistics can be connected, but for fun it can be taken further

I regard Factorissimo as a basement mod, so the same concept could work for underground, adding vehicle underground lanes not just resources / circuits and liquids in/out ports. Speaking of which player in a vehicle can't travel between surfaces afaik, but Factorissimo and modmashsplinterunderground_1.1.43 suck me unintentionally in when I travel in a hover car. There should be an option and a key to enter by choice or automatically

There's transport drones which I use too, for using trucks and roads to deliver things in the base, so basically every logistics mod, and vanilla, can be routed through a special building like an elevator through a tunnel to elsewhere for whatever reason, such as extending the logistic network safely to far outposts. Trick perhaps would be making the logistics see the elevator connect to the network, then just have the drones teleport between surfaces of which they should probably be unaware, while they continue working on preset logistic networks

65K downloads
https://mods.factorio.com/mod/Transport_Drones
*since these travel on roads like trains making them enter a tunnel should be fairly easy

Since paths are available, again making an AAI vehicle go to a building / unit (the elevator / tunnel) by path, and getting teleported at that location, then continue on another path underground (with unit controller help perhaps to set the new path) should make AAI vehicles routable between surface and underground. Only problem with AAI vehicles and AAI programmable structures I noticed, the vehicle AI get mixed up if teleported / mined / spawned, and unit controller only works from the same surface too, so getting random haulers pop up there's no guarantee they'll get the same id and follow on multiple paths in a determined way with a determined load, unless making extra complicated circuits to determine the hauler's purpose. Setting the hauler's id manually would've solved this

Flying drones should be easy, like seeing the elevator / tunnel as a special chest, and have the other logistic network underground set the chest's request so drones entering the chest would be teleported to underground and continue through the other logistic network

P.S. modmashsplinterunderground_1.1.43 has funny issues like not delivering power back to the surface which makes it unusable for tunneling power to far outposts or making underground power stations. Also if it has enemies enabled it kills UPS so don't recommend that direction. Also claims it can't use liquids, and I'm sucked by its teleport underground every time I touch that building unintentionally

EDIT: actually spidertron travels inside factorissimo-2-notnotmelon_1.2.2, which is another surface, so it's very much doable

[NathaU]

My thoughts about that:

Logistic drones:
Senseless to make an elevator logic as the logistic network only works on the surface the roboport is.

Spidertron, cars:
Seems doable

AAI, Transport drones:
too complicated, I won't do it for now

tunneling from underground to the surface:
maybe, but the mod is supposed to be somewhat challenging and not just to bypass enemies

[angrypidgeon123]

> Logistic drones: Senseless

Scenario: you build your base partly underground (and people just cover everything in logistic areas). Then your underground and surface networks being connected makes it seamless to make logistic requests from anywhere

Scenario what: make drones see ground and underground networks as connected. Doesn't work directly? Fake it

It is a QoL feature, since delivering items by logistics can already be done by placing logistic chests then deliver resources between surfaces via existing item / fluid buildings, just that there is more work to do

How to fake: a logistic network basically has requests and supply, therefore:

1. Need a structure that syncs the logistic signals between surfaces, and syncs requests so that:

2. A drone goes to the logistic signal sync structure being fooled it can collect items there (which it can with a twist):
   1.1. When drone goes to the logistic signal sync structure and interacts with it, instead of being given the item, it is teleported, assigned the new surface and new logistic network from the other surface, while going about the same order. As a result the drone will be going for the supply in the other surface network and collect the item. After collecting the item it will look for the request, which again will be a sync structure that teleports the drone back in the same fashion

3. Need a structure that syncs the requests between surfaces. The drone that has fetched an item will go to deliver the item to this special building but instead of depositing the item there, the drone will get teleported and connected to the new surface and logistic network that originally made the request

Note: possibly an UPS killer

Mods that already do this partially, to copy code from:

1. CpeBotRecaller_0.14.1, it calls drones to be extracted from the logistic / construction network
2. modmash subways work by teleporting the train and wagons between surfaces

the mod is supposed to be somewhat challenging and not just to bypass enemies

You'll do as you like of course. Personally don't agree with anything that is unrealistic (I read your todo list). Suffocating underground makes sense (and using the space suit to avoid that), but it's also an annoyance to change into a suit every time I'm traversing the underground, so a powered venting system should work, and if the pollution is the way suffocation is considered, air filtering should work. I have a mod or two for filtering. The way it is now, it doesn't seem that pollution works however I haven't tested thoroughtly - I have no industry underground, only the haulers pollute, and on the surface my pollution is sucked away by air filters (since my evolution works only when nests eat pollution as it should). Other features whether realistic or not can be annoying. For now I just need a fully functional underground and everything else should be made optional (with in-game enable / disable options) else I will edit it out for myself, and other who do not know how will bail on the mod

IMO the underground works because it expands the Factorio universe realistically (not just to bypass enemies but whatever; avoid CMEs, have a funky base architecture, tunnel into an enemy player base (surfaces should be in sync, and alert mod exist for proximity so tunneling down then up and be guarded against). Personally because I aim to play with almost unbeatable enemies, my base will always have space constraints so underground and space are solutions, but it's quite useful to ferry resources from one end of the base to the other without using a train via tunnel. So there's many uses for underground, but if you make cheap difficulties about it, it will drop in popularity, e.g. I don't care for the new 1.0.5 elevator animation for the character, it wastes time just like the small cooldown for teleporting between factorissimo surfaces, and it annoys. I have an extensive experience with such mods, like Terraforming / Shifting Sands mod which requires you to build foundations for all buildings, it's cheap difficulty and ultimately had to delete it because it's pointless - installed instead a mod that increases building hp if building foundations which is optional, not like Terraforming / Shifting Sands that annoyingly blocks building. Rampant mod made it that you can't build anything near enemy buildings which I understand, however enemies makes buildings so close that I can't build inside my base / outpost until I destroy the enemy... mod doesn't asses territory and ends up being annoying, so it's not just modding, it's salesmanship / politics

P.S.
Spidertron and cars already teleport inside factorissimo so it's just a matter of copying the code, but that's only useful for automated spidertrons and cars, which I don't use yet as in factorissimo almost makes no sense since can deliver stuff by belt and even chest inside. Being sucked in another surface is an abomination, I already fixed it in factorissimo for myself:

https://www.reddit.com/r/factorio/comments/1bkbm4y/this_is_how_to_stop_slipping_in_factorissimo_with/

However for underground makes sense, even more so with AAI haulers which I already use. Scenario: I play with 600% enemy size and max frequency of everything, so my only realistic option to ferry stuff was to tunnel under the enemies and pop up again in the oil fields, barrel the oil and have a hauler automatically traverse the tunnel back to the base. If the setup would me more complicated, it would make sense to make the hauler teleport from underground to the surface and continue on a new path, though as I probably already foresaw, the AAI has issues because of assigning ids automatically and not accepting custom ids so 1 hauler would work, 2 would need a very complicated circuit to deterministically assign orders when changing surface. I already have 2 underground, for copper and oil

Again it is a QoL feature, the connection is already done with buildings that ferry the resources between surfaces

[angrypidgeon123]

Also a separate suggestion: tunneling produces too many stones, I never need to mine stones if I go underground, all the more so miners can be automated. I still have the warehouses full of stone from mining from when I made the tunnel to the oil fields 50 game hours ago :D

Too much stone drops also makes tunneling more difficult which annoys

I'ld say even 2x less stone is fair. I appreciate the other modmash underground for this one reason, though the only reason

Realistically just digging doesn't produce usable stone that much, which needs to be the right quality also. It would produce dirt mostly which needs to be disposed of, for which Factorio has no explicit system. Industry produces waste also, but I avoided the mod for that...

Also I repeat the synchronization of resources between floors, about the idea of tapping into ore veins underground. Maybe difficult, probably UPS unfriendly, but realistic. Synced surface quantity should represent the entire vein quantity, not that digging finds more since that's assumed

Regarding the difficulty of not being able to dig under water, it's unrealistic for 2 reasons: I have water as a resource mod which can drain dry lakes, even oceans with enough effort (which wouldn't reflect in your mod). Also, in real life tunnels have been made under the sea, and that should be a feature for underground mod - you basically deny one of your mod uses. If you really want to make it realistic, then you should consider water depth so for lakes digging under at level 1 is enough, for oceans needing to go to level 2 underground to tunnel under... and I can tell from water as a resource mod that scanning water bodies is resource intensive or lengthy to not kill the UPS, or, it can implemented by checking in real time underground tiles that are being dug, with surface tiles. I think it's unnecesary complications...