# A guide to bridges and how they help you achieve efficiency and flow

## Recommended Posts

Tobruk    341

INTRODUCTION

First things first, since this section is mostly dedicated to those, who are barely beginning their adventure with ONI - Liquid and gas in pipes flow from the green arrow to the white arrow.

In this example, liquids will flow from the left to the right.

Quote

You can cleverly use the fact that pipes don't differentiate between pumps/consumers and bridges. To them, it's one and the same, since all of them use identical white/green arrows. This makes possible to run liquid/gas in circles without any power once you get the material into pipes.

For very simple pipes (just like the ones above) that go from just one pump (green) to one consumer (white) and are relatively short, you can just connect the two and be done with it.

It is advisable, though, to always include a few bridges along the way, if the pipe is supposed to be long, as in the picture. This way you won't need to do any cumbersome adjustments when crossing multiple lines with one pipe.

Quote

Bridges may seem counter intuinitive, as they teleport packets from white to green. Still, you can kind of rationalise it this way - imagine the white part of the bridge as a vent, where liquid is dropped, and the green part of the bridge as the pump that picks it right back up.

I hope that this will help you to avoid any confusion regarding the packet direction.

Some people prefer to deal with such a situation by making a one-tile gap between each pipe and then crossing them using multiple bridges, but it looks ugly and takes up more space.

It's much better to do it like this, which looks way more neat:

There is nothing difficult here to explain. Look at it as just an extended version of the second picture (times three :D), with a vertical pipe going underneath the main pipelines.

INTERSECTIONS

Intersections split the flow into two halves, as shown below:

P.S Someone rightly mentioned that the percentages given here should be treated merely as approximation over several cycles of operation. A packet passing an intersection will not divide itself like a living cell in two. It will just pick one route and stick to it.

The percentages therefore is the overall amount of oxygen transferred to each vent over several cycles.

FLOW PRIORITY

MAIN PIPE v. AUXILIARY PIPE

Suppose you have a main pipe that feeds a sieve with polluted water from the showers, but also another pipe with polluted water from a geyser. Suppose further that you want the main pipe from showers to have priority when it comes to feeding the sieve. You can achieve that using bridges:

In this example, unless there is no flow from the main pipe (or the packets that go through the main line are less than full), auxiliary line will push their liquid into the main line and support it, achieving constant flow.

Another example showing how you can make a certain pipe wait its turn.

SPLITTING FLOW

When splitting a single pipe with bridges into two pipes, you have to decide, how you want the piping to behave. There are two options:

• Move stuff ONLY through route 1, unless route 1 is backed up, then ALL go throug route 2.
NOTE: The bridge below is there only to guide the packets in the right direction. Such an application of bridges is a common one, so don't be afraid to use them like this.
• Move stuff EQUALLY through route 1 and route 2. Flow is split in half.
REMEMBER: the split has to happen AT the green arrow, not after, not before, or else it won't work.

MULTIPLE CONSUMERS ON A SINGLE PIPE WITHOUT BRANCHING

Connecting consumers like this can have its application, but generally should be avoided (the three vents to the right will not be used).

However, if you have consumers that needs really miniscule amounts of liquid, you can chain them like this (unless you have like twenty of them - always check if the consumers' demand can be supplied by one pipe)

MULTIPLE PUMPS ON A SINGLE PIPE

This is not a desirable situation, as just one pump is enough to saturate the pipe. It could work with buildings that produce material in lesser quantities (let's say PH2O from carbon skimmers), but as a rule of thumb never arrange them like the pumps below (in a straight line, each green going INTO another green).

Instead, stagger them like this, so an individual producer can never occupy someone else's green output point.

In this case though, you don't need to create four vents to service these four pumps nor four pumps to saturate one pipe line! One of each is enough.

GAPS BETWEEN PACKETS

• Splitting pipes into two lines creates a gap between packets if packet in the side branch is not full (happens all the time with almost all consumers). The problem occurs because the pockets in the main line have to stop, resupply the packet on the side branch (with like 10 g or sth) and only then move further.

(P.S this problem seems to be obsolete as of the launch version!)

To avoid it, make the split at the green arrow of a bridge. Bridges teleport packets, so stopping does not occur in this example.

BUS BRANCHING

Buses is a line of multiple pipes going in the same direction transporting vital resources like oxygen or water. You want to branch out of the bus at certain places to deliver these resources, but having multiple pipes makes this a difficult task.

If you want to branch out with only one pipe:

NOTE: Refer to section SPLITTING FLOW to decide whether it's better for you to branch from the green arrow or the white arrow. Here I'm branching from the green for equal distribution.

If you want to consolidate multiple pipes (for example you have 3 pipes with oxygen and don't want to strain just one):

1. Branch out with the first pipe (shown above)
2. Branch out with the second pipe (AS MAIN PIPE - see relevant section)
3. OR: Branch out with the second pipe (AS EQUAL DISTRIBUTION - see relevant section)
4. Branch out with the third pipe (again, choose whether it's auxilary or main)

PUTTING THINGS INTO PRACTICE

20W PIPE-SENSOR FILTER

Filters based on pipe sensors need constant flow of liquid/gas in order to work effectively and filter out what you want.

Let's again use the fact that materials can move in circles in pipes ad infinitum to achieve that constant flow.

• The "staircase" in the middle is where your liquid will circle around forever, unless picked up by the sensor. (see INTRODUCTION)
• Sensors lie on each of the stairs, waiting for a proper packet to arrive and they filter it out into the branching pipes on the right (see MULTIPLE CONSUMERS ON THE SAME NON-BRANCHING PIPE)
• The very first bridge on the left is there to prevent newly pumped liquid (see AUXILARY PIPE) to pass into the filtering circle before the old liquid circles around and has not yet been picked up.

Hope I helped someone with this guide.

I intend on expanding upon this when I have time

Edited by Tobruk
• 2

##### Share on other sites
Djoums    91

Nice explanation of the core pipe mechanics, thumbs up !

##### Share on other sites
psusi    307
1 hour ago, Tobruk said:

This is not a desirable situation, as just one pump is enough to saturate the pipe. It could work with buildings that produce material in lesser quantities, so that they can support each other.

True for liquid, but not gas.

##### Share on other sites
Nitroturtle    636

Excellent post breaking down one of the stranger mechanics in the game.  Wish I had something like this available months ago when I started playing, as this is something I struggled with initially (and still do sometimes).  I wish they made it a little more intuitive, but at least it offers considerable flexibility once you understand the mechanics.

##### Share on other sites
Soulwind    303

Your section on intersections is technically true,  but is a bit misleading for new players.

Intersections alternate in use, so yes the effective flow rate is halved by each intersection in the entire pipe, but individual packets are not spilt. Nor is it sequential as your example makes it appear. I.e. having 3 intersections isn't 1/2 flow. 1/4 flow, 1/8 flow.  It is 1/8 effective flow overall.

Clear to us, but can be confusing to newbies.

##### Share on other sites
Slvrsrfr    191

Excellent. Thank you much.

##### Share on other sites
psusi    307
1 hour ago, Soulwind said:

Nor is it sequential as your example makes it appear. I.e. having 3 intersections isn't 1/2 flow. 1/4 flow, 1/8 flow.  It is 1/8 effective flow overall.

Umm.. what?  You get half going each way at each split.  Half of half is 1/4.

##### Share on other sites
heckubis    138

no its whole packets that change directions it dosnt split the package 1000 grams a packet will still  be 1000 grams when it goes on a different path. if you want a path split with less then the feeding packets volume you need valves. valves are unspoken of for some odd reason sure bridges can be built over but provide no direct control over the flow.

splitting packets with valves does not alter the flow rate just flow volume no missing packets no gaps in flow just what you wanted and how much of it

going from a valve to a radiator for cooling then bridged back on after the valve will keep water constant, mix temps and still not block flow rates.

Edited by heckubis

##### Share on other sites
Mariilyn    288

It would be a good idea to tackle efficient exosuit dock piping, as many players probably struggle with this.

For a long time, I used a tree-like configuration for the exosuit docks and they were clearly not refilled fast enough. They were staying half-empty while the room receiving the surplus oxygen (which doubles as a puft farm) was reaching 20 kg per tile and constantly interrupted the oxygen production. I eventually reorganised all my piping, and everything works much more smoothly.

Here is my favorite configuration for the exosuit docks :

Exosuits can be refilled 3 at a time and the flow of oxygen is not slowed down because of branch splitting.

And here is one example of bus branching for the main oxygen supply line of a large base, featuring a vertical pipe crossing :

##### Share on other sites
SamLogan    977

Thanks Tobruk and the other for that really interesting topic.

##### Share on other sites
Albryant    78
24 minutes ago, Mariilyn said:

Exosuits can be refilled 3 at a time and the flow of oxygen is not slowed down because of branch splitting.

You can do 4 at a time.  I think there was a post by @Lifegrow a few months back showing this technique with exosuit docks.

##### Share on other sites
beowulf2010    671
47 minutes ago, Albryant said:

You can do 4 at a time.  I think there was a post by @Lifegrow a few months back showing this technique with exosuit docks.

Yep. The fourth pipe goes back under the bridge before going out to the side. I almost always use exosuit docks in 8s so this is perfect for me.

1 bridge to split to the 2 bridges feeding the 4 trees.

##### Share on other sites
Lifegrow    1710
6 hours ago, Albryant said:

You can do 4 at a time.  I think there was a post by @Lifegrow a few months back showing this technique with exosuit docks.

Think the original thread was started by Kasuha, but the ideas been floating around reddit/here for a while.

Heres an artists rendering (commissioned due to not wanting to load up ONI)

Spoiler

##### Share on other sites

Hey sorry to necro an old thread but I went to share the link to this post with someone and noticed the images are no longer working.  Would there be any possibility of resurrecting them?  Not even sure OP still plays or participates here any more but is there any chance the images are backed up somewhere on some hard drive?

This page has been such a great resource since I started playing ONI, much appreciated!!

Thanks!

• 2

##### Share on other sites
psusi    307

How the heck did this thread not get archived?

• 1
• 1
• 1

##### Share on other sites
SamLogan    977

You have also this one :

• 1

##### Share on other sites
1 hour ago, SamLogan said:

You have also this one :

Thanks, much appreciated!  That thread's OK but not as good as this thread was IIRC.

##### Share on other sites
TheMule    325
On 8/28/2018 at 7:54 PM, Mariilyn said:

It would be a good idea to tackle efficient exosuit dock piping, as many players probably struggle with this.

For a long time, I used a tree-like configuration for the exosuit docks and they were clearly not refilled fast enough. They were staying half-empty while the room receiving the surplus oxygen (which doubles as a puft farm) was reaching 20 kg per tile and constantly interrupted the oxygen production. I eventually reorganised all my piping, and everything works much more smoothly.

Here is my favorite configuration for the exosuit docks :

Exosuits can be refilled 3 at a time and the flow of oxygen is not slowed down because of branch splitting.

And here is one example of bus branching for the main oxygen supply line of a large base, featuring a vertical pipe crossing :

So far, the setup I like the most it this:

the most used docks are the ones on the left. So ideally:

is even better.

Edited by TheMule

##### Share on other sites
Tobruk    341

I restored the dead links and added some clarification where I felt my old self left things unsaid.

Also, did you know that packet gaps are no longer a thing in the game (see: GAPS BETWEEN PACKETS) ? Yup, found out about this some time ago.

Edited by Tobruk
• 1

##### Share on other sites

Thank you so very much Tobruk!!  You're a saint!!

• 1
• 1

##### Share on other sites

I'm a new player, loving the game - but really struggling with this even after reading this. Can't help but feeling an idiot. What is the fundamental rule about how the bridge works? What defines whether or not a packet goes into the bridge or continues on? Maybe that is what I am missing...

##### Share on other sites
7 hours ago, tdellaringa said:

What defines whether or not a packet goes into the bridge or continues on?

That's easy, a packet goes into the bridge it the bridge's output is not blocked, and does not go if the output is blocked (and in this case if there is another pipe leading away from the input, the packet continues there).

What's also important to understand is that packets do not travel continuously like the animation shows, but they jump to the next pipe segment instantly (once in each second). It's easy to observe this if you fill a pipe with heterogeneous content (like different materials, they are the easiest to see) and hold your mouse over a pipe segment and watch the content of the pipe. So "being blocked" means that at the moment this jump occurs, the packet in the pipe segment under the output port has nowhere to go, and not blocked means this packet can jump to somewhere else, making free space for the packet coming through the bridge.

There is one more important behavior: if you have a pipe that has a continuous packet flow, and you put the bridge output on the middle of this pipe, the game will prioritize the flow in the pipe. To put it another way, if the pipe segment under the bridge output has an incoming pipe, a packet will be drawn from the incoming pipe and not through the bridge. It fits with the general mechanism: packets already in the pipe make the pipe blocked, blocking the bridge.

Maybe one more thing that might be confusing based on the animation: when a packet enters the bridge, it means it appears instantly on the output. The animation looks like it is entering the input pipe segment, but the input pipe in this case actually remains empty. If the packet cannot enter the bridge, it remains in the input pipe segment, and the animation looks exactly the same.

(NB. this explanation assumes full packets, bridges also handle partial flow, but I guess you already noticed that.)

Edited by Urist McPilot

##### Share on other sites
Tsabo    55
On 8/28/2018 at 9:34 PM, Tobruk said:
• Move stuff EQUALLY through route 1 and route 2. Flow is split in half.
REMEMBER: the split has to happen AT the green arrow, not after, not before, or else it won't work.

Is this right?

I'm not on my gamin' machine right now to check, but everything i remember says that if you split the pipe after the green arrow (but before the outlet) it will indeed work.

##### Share on other sites
psusi    307
3 hours ago, Tsabo said:

Is this right?

I'm not on my gamin' machine right now to check, but everything i remember says that if you split the pipe after the green arrow (but before the outlet) it will indeed work.

Yes, that is incorrect; just a standard T junction will split the flow.

##### Share on other sites
3 hours ago, Tsabo said:

if you split the pipe after the green arrow (but before the outlet) it will indeed work.

Actually the picture does not have a pipe split at all It's one single pipeline with an output port placed in the middle, and it can be placed anywhere.

If a single pipe runs from the output and it is split later, it will have a similar behavior, although IIRC it has some minor differences in case one of the routes back up.