Suction Piping and Gravity Pumping

[Mutio]

So,  I am a nuclear reactor operator by trade, and this obviously means that I absolutely love this game, especially the gas and liquid systems.

That said, the implementation of the gas and liquid systems is...odd.  I have operated many dozens of systems containing everything from pure water to radioactive gases and everything in between.  With that in mind, the system in the game presently is really strangely designed and this limits what you can do with them and how effective they are.  Two major shortcomings are the lack of intake piping for both liquid and gas systems.  As well as the inability to move gases or fluids by use of gravity or pressure differentials.  The latter ties into the former.

Very few pumps in my experience, be they gas compressors, fans, or liquid pumps, are simply placed inside the fluid  volume you want to move.  This makes sense for a lot of reasons.  One reason is that it submersion doesn't allow for different suction sources to a given pump to be aligned.  Each pump can draw from only a single tank in the current system, which really limits the types of systems that can be built and makes systems that could make use of a single pump require many.  Plus, it would be hell to perform maintenance or replace pumps if they were always inside liquid or gas tanks.

Closely related to all of this is the inability to gravity or pressure pump inside the piping systems.  Without non-pumped inputs you can't create passive fluid systems.  In practice, once should be able to place a non-pumped intake inside a volume of fluid at an elevated location or pressure, run piping from there to a lower elevation or pressure area, put a vent on, and gravity or pressure should do the rest.

[Kasuha]

ONI physics  is ... inspired by physics of real world. They're however not the same, they're not even similar, except on first look. It's better to keep that on mind when playing. Gas/liquid simulation is limited by CPU power that is available on lowest spec machine that's supposed to run the game. For that reason, there's just one element per tile - it can be solid, it can be liquid, or it can be gas, in all cases of single type. They don't mix. A lot of problems and limitations come from that choice but for what I know, we're going to be stuck to that till the end of the game's life unless a miracle happens.

Pipes work like intestines, they move their contents using peristaltics, driven by chemotaxis caused by inputs and outputs. Pumps are like mouths, they only move the liquid or gas into the pipe. And just like in living bodies, gravity doesn't quite play role in the system.

 

[thebebinator]

I really agree with the inputs being separate from the pumps, that would be an amazing change. 

[Mutio]

12 hours ago, Kasuha said:

ONI physics  is ... inspired by physics of real world. They're however not the same, they're not even similar, except on first look. It's better to keep that on mind when playing. Gas/liquid simulation is limited by CPU power that is available on lowest spec machine that's supposed to run the game. For that reason, there's just one element per tile - it can be solid, it can be liquid, or it can be gas, in all cases of single type. They don't mix. A lot of problems and limitations come from that choice but for what I know, we're going to be stuck to that till the end of the game's life unless a miracle happens.

Pipes work like intestines, they move their contents using peristaltics, driven by chemotaxis caused by inputs and outputs. Pumps are like mouths, they only move the liquid or gas into the pipe. And just like in living bodies, gravity doesn't quite play role in the system.

 

The inspired by real world but not the same thing is silly.  They are clearly going to great lengths to make parts of the game as realistic as possible.  Heat travels from hot areas to cool areas.  Gases from high density to low.  Liquids flow downhill.  Materials properties like thermal conductivity, melting, freezing and boiling points culled from reality.  Ultimately, however, my argument was not based on making things more realistic for its own sake.  Rather it is about using the systems they already have in the game to make things as intuitive as possible.  None of the changes I proposed would involve entirely new processes or modeling

The game already models gases flowing from higher pressure (density) areas to lower pressure (density) areas.  Each block checks adjacent blocks to determine which way gases will propagate.  For a pumpless system to work the game would only need to apply that same logic to the intake block and the vent block when determining flow to adjacent areas.  The pipe in that case acts merely as a bridge for two points  to allow the transfer to occur.  Likewise in the case of gravity pumping, gravity is already applied to fluids so you merely need to compare the elevation between intake and discharge locations.  If the intake is higher and submerged then the fluid should move within the pipe just as it would without, by you say digging a channel between the two.  I am not proposing a whole new system for piping, rather just applying the same modeling and principles the game uses outside of piping to the inside of the pipes.  Again, this makes it more intuitive because you already spend much of the game using these principles outside of the piping systems.  Already each type of piping is exclusive to that state of matter, so there isn't any issue of a block needing to be more than one type.  Perhaps you can expand on why you think what I have proposed will require a given tile to be more than one state of matter.

Continuing as it is will essentially paint the game into a corner where the liquid and gas systems are un-intuitive, which isn't good game design.

[Kasuha]

7 hours ago, Mutio said:

The inspired by real world but not the same thing is silly.  They are clearly going to great lengths to make parts of the game as realistic as possible.

Well... water can be used to produce oxygen and energy. Water is a fuel. No, I don't consider that realistic or anywhere near realistic and I'm pretty sure it's going to stay that way.

I believe it's better to accept that ONI physics is unique than to expect it to be realistic.

[Kasuha]

Okay, let's get through your observations and why I call the game physics 'inspired':

7 hours ago, Mutio said:

Heat travels from hot areas to cool areas

Heat transfer is very arbitrary. Walls act as thin metal plates, providing almost no thermal insulation between spaces on either side. Heat is apparently more readily transferred between wall and gas than between two neighboring gas tiles. And then there's abyssalite, an element that has next to no thermal conductivity. And wheezeworts that destroy heat. And Thermal Regulator which also destroys more heat than it itself produces.

7 hours ago, Mutio said:

The game already models gases flowing from higher pressure (density) areas to lower pressure (density)

Gas pressure is represented by number of grams per tile. 1 kg of carbon dioxide is the same pressure as 1 kg of hydrogen, also regardless of temperature. Gases have no inertia, flow between high and low "pressure" areas is done through diffusion and is extremely slow, in larger rooms it may take number of cycles for the pressure to equalize. 

Also gas stratification is arbitrary and does not match real world gas density differences.

There is liquid carbon dioxide, though only in very narrow temperature range

There's no state change enthalpy

7 hours ago, Mutio said:

Continuing as it is will essentially paint the game into a corner where the liquid and gas systems are un-intuitive, which isn't good game design.

It only gets unintuitive if you expect the game to be realistic. It is not. Don't expect it. The physics is inspired by reality but then it is bent to support gameplay, and it is bent in unique way through devs' arbitrary choices. At present these choices depend on each other and support each other. It certainly is possible to make the game similar level of fun and more realistic but that would require so many changes that it would be a different game.

 

 

 

[avilmask]

While playing, I also was hoping I could manipulate the air flow to create balanced ventilation (low density zones don't really suck air in) and temperature  system (cold air doesn't "sink" in hot). And due to dupes occasionally walking into rooms and create little portions of CO2, there's always a 50-100g layer of it on the ground in closed rooms, making air pressure balance a mess. If only you could make it move to air pumps.

[Mutio]

5 hours ago, Kasuha said:

Well... water can be used to produce oxygen and energy. Water is a fuel. No, I don't consider that realistic or anywhere near realistic and I'm pretty sure it's going to stay that way.

I believe it's better to accept that ONI physics is unique than to expect it to be realistic.

You can literally do that in real life.  Applying an electrical current to water produces oxygen and hydrogen.  It is called electrolysis.  We've know about it for 217 years.  Hydrogen is an extremely flammable gas, which means you can use it in any of a number of combustive processes once you've extracted it from water.  Alternatively you can use it power fuel cells.

[NanoD]

16 minutes ago, Mutio said:

You can literally do that in real life.  Applying an electrical current to water produces oxygen and hydrogen.  It is called electrolysis.  We've know about it for 217 years.  Hydrogen is an extremely flammable gas, which means you can use it in any of a number of combustive processes once you've extracted it from water.  Alternatively you can use it power fuel cells.

Yeah. BUT you cant gain energy like in ONI. 

You can produce 20 KW of heat with only 960 W of energy.

Dupes breaths 100g/s of oxygen only breath out 2g/s of CO2. 

Gases is mixed in RL. they are not in ONI. 

And dupes are made of Genetic ooze.

So yeah ONI have taken inspiration on the physics from the real world. But is game physics of ONI. 

[Kasuha]

1 hour ago, Mutio said:

You can literally do that in real life.  Applying an electrical current to water produces oxygen and hydrogen.  It is called electrolysis.  We've know about it for 217 years.  Hydrogen is an extremely flammable gas, which means you can use it in any of a number of combustive processes once you've extracted it from water.  Alternatively you can use it power fuel cells.

No, you cannot do it in real life. You can electrolyze water, yes. It costs a hell lot of energy. And you can burn the resulting hydrogen, but for that you'll use all the oxygen you just created, and in return you get less energy than what you invested to the electrolysis, plus all the water you started with. You don't end up with oxygen and surplus energy. Real physics obey conservation laws. 

 

[n37runn3r]

The closest you get to gravity pumping is my sloppy method of digging vertical or angled shafts and draining the water down them. it moves like it's sticky or gelatinous rather than being a true liquid, so the flow is really weird but it does work.

[CodingKitteh]

Wait till you try to rationalize phase changes .

I was disappointed to find out the discrepancies of real life physics vs in-game physics but I learned to make amends with it. I do hope that the Devs will constantly look to make the game more in line with the physics of our universe. Most the mechanics work on a basic scientific knowledge. Anytime you jump into expert mode, stop! 

 

Also I believe pressure is grossly simplified or possibly not simulated at all. I have never used units of mass ever in my life to describe pressure. It's torr, pascal, bar, atm, and (dreadfully) psi. Every time I try air cooling in game. It frustrates me the most. The gas in this game does not expand to the container size fast enough. I have had machines over heat because of the partial vacuum the "pressure differential" generates.

[thebebinator]

Although I kind of agree with some of the non-intuitiveness, but when talking about realism, keep in mind that you're printing dudes from a machine that live in the middle of a space asteroid.

[brummbar7]

And most importantly, there's a point of diminishing returns.  The game already gets laggy with too many dupes and too much map exposed.  Making the physics any more real is probably only going to make that situation worse.  So what's really more important?  Personally I'd rather have things generally plausible, but efficient enough to have the map exposed and have a ton of dupes, vs super-technical and slows my computer to a crawl at 10 dupes and half the map.

[Nullpersona]

An optional intake pipe connection on gas and liquid pumps would be great, especially if there was a toggle between local and remote feed.

[Siege57]

On 6/3/2017 at 6:26 PM, CodingKitteh said:

...

Also I believe pressure is grossly simplified or possibly not simulated at all. I have never used units of mass ever in my life to describe pressure. ...

The units of pressure in the game are not mass. The units in the game are mass per tile. When you consider that, they start to look much closer to real world pressure units. The only difference is that the game uses mass per area instead of force per area. And that's a decision I think we can all get behind. They didn't convert from mass to weight, because why burden us with an arbitrary gravitic constant for our space rock and units of force when everything else in the game already uses mass values.

Okay, now let's get really nerdy. Correct me if I'm wrong, but it would be a completely unnecessary linear multiplication. In fact, if the gravitic constant of our space rock is exactly 1 Newton per kilogram (which is probably a feasible number for a big-ass meteor or a tiny moon) then the game's units for pressure are exactly right. They are just using kilograms of force instead of kilograms of weight. You know, the exact same confusing dumb thing the imperial measurement system did when it accidentally created pounds of force and pounds of weight before gravity was properly understood.

[Kasuha]

2 hours ago, Siege57 said:

... then the game's units for pressure are exactly right.

except that 1 kg of gas in a tile represents the same pressure regardless of gas type (1 kg of hydrogen is the same as 1 kg of carbon dioxide) and temperature (1 kg of hydrogen at -100 C is the same as 1 kg of hydrogen at +100 C). That's not how pressure works in real life. Hot air and helium balloons work because the element they contain needs less mass in given volume to create pressure equal to the surrounding air.

 

[Trego]

6 minutes ago, Kasuha said:

except that 1 kg of gas in a tile represents the same pressure regardless of gas type (1 kg of hydrogen is the same as 1 kg of carbon dioxide) and temperature (1 kg of hydrogen at -100 C is the same as 1 kg of hydrogen at +100 C). That's not how pressure works in real life. Hot air and helium balloons work because the element they contain needs less mass in given volume to create pressure equal to the surrounding air.

 

But pressure in the game doesn't work like pressure in real life...so...the game's units for pressure are still exactly right.  right?  I mean, it would be cool if the ideal gas law were simulated, as that would give us a lot of new tools, but it's just not.

[Kasuha]

6 hours ago, Trego said:

But pressure in the game doesn't work like pressure in real life...so...the game's units for pressure are still exactly right.  right?  I mean, it would be cool if the ideal gas law were simulated, as that would give us a lot of new tools, but it's just not.

I was reacting to someone's statement, check the quote. I am fine with how the gas in the game works, but no, it is not anywhere near real gas.

[Siege57]

I just said that the units for pressure aren't as wonky as they appear. I did not mean to posit that the game physics are not super gamified. They are.

Sorry OP, didn't mean to sidetrack discussion here. Let's all get back to discussing OP's excellent suggestion that Klei include a "passive intake" for gases and liquids. It's maybe a small, do-able ask. If we suppose that a tile of gas or liquid has code that interacts with the 8 adjacent tiles, adding a "passive intake" pipe to the tile just means that you could run the same code on those 8, and also on tiles that have vents.

You can already get liquid to the bottom of your base or hydrogen to the top of your base for free by physically digging holes. This would let you accomplish the same with pipes, and just feels more elegant than building a pump every time. Although, in the end, I suppose it wouldn't really change gameplay much besides removing several -120W pumps from your grid. Hmm. Can anyone think of something cool you could do with "passive intake" pipes that you couldn't accomplish by just ponying up the 120W for a regular pump intake?

Edit to add - maybe existing pumps should just have a "passive intake" toggle that would let water fall or hydrogen rise through the pipe passively without needing the -120W.

[Momotall]

This is a game, not real world or a physics simulator. If a more realistic in-pipe liquid model is added to the game, everyone will need to learn hydromechanics in order to pump water to their wanted places. The game will be too hard for most players. You should have noticed that in game the mass is not conserved, entralpy is not conserved and entropy is not conserved. These facts are wrong in real world but they are a part of ONI game mechanics. Game developers need to find a balance between reality and difficulty. What we are playing now is just a result of balance. I gave some suggestions on adding more complex system in the game like logic circuits and microelectronics. These system will not change the method you play the game now, you can just ignore them if you dont want to use them. But a change to liquid flow mechanics will make the game different (harder I guess) for everyone.

[brummbar7]

2 hours ago, Siege57 said:

Although, in the end, I suppose it wouldn't really change gameplay much besides removing several -120W pumps from your grid. Hmm. Can anyone think of something cool you could do with "passive intake" pipes that you couldn't accomplish by just ponying up the 120W for a regular pump intake?

I think saving those 120w per pump is a large part of the point of the suggestion.  But in addition, it would make it easier to transfer fluids/gases, because by duct/piping it, you can also have your dupes circulate through the duct/piped section.  So for instance if you want to connect all your gas geysers so that you can run fewer pumps, currently you have to make 'alleys' between them.  Then you either have to circulate around those alleys, or make airlocks through them.  Allowing it to flow through ducts passively would save the pump AND make it easy to circulate around them.  Same deal with reservoirs.  You could easily connect dispersed reservoirs and move around them, as opposed to having a giant monolithic reservoir you have to go around.  These are not insignificant benefits.  Regardless of how 'realistic' this would be, I think it's more a matter of game balance and code overhead.