Liquid Viscosity

[rgduck]

The viscosity and surface tension of water seem way, way off. Like in the attached screenshot. That's a three foot bubble maintained only by surface tension! Water in ONI is more viscous than molasses is in real life!

This produces some really goofy-looking phenomena. Pools maintain a dramatic slope for cycles, waterfalls persist with just a few grams of liquid, and flat surfaces fail to drain. This has meaningful implications for gameplay, too, since dupes feel so strongly about getting their feet wet.

I relaize there are quite a few oddities created by how ONI models physics, but this one strikes me as a really easy fix. There must be a parameter for viscosity somewhere, and maybe a second for surface tension. Those numbers just need to be changed for water, no?

PS: Apologies if this is a repeat post. I tried posting it before, but I don't see my post in the forum now.

[sakura_sk]

Here it is?

 

[Prince Mandor]

3 hours ago, rgduck said:

The viscosity and surface tension of water seem way, way off

 

Well, this game is not physics simulator. Really, it even not support quantum effects inside atoms

Seriously, there are no liquid tension, and no pressure, only mass. Game do not have 'viscosity', just amount of mass to begin shifting liquid left and right.

And this game happens in square grid, and only one element can exist in one cell.

This is a game, not real world

[gabberworld]

59 minutes ago, Prince Mandor said:

Well, this game is not physics simulator. Really, it even not support quantum effects inside atoms

Seriously, there are no liquid tension, and no pressure, only mass. Game do not have 'viscosity', just amount of mass to begin shifting liquid left and right.

And this game happens in square grid, and only one element can exist in one cell.

This is a game, not real world

you could not calculate with home pc the complex stuff either in live mode

that also made me think why not add support for multy pc XD

[Fradow]

1 hour ago, Prince Mandor said:

Seriously, there are no liquid tension, and no pressure, only mass. Game do not have 'viscosity', just amount of mass to begin shifting liquid left and right.

Small nitpick on that part (the rest is correct): there is pressure for liquids (not for gas) in the game, which can break tiles, as explained on the wiki, and there is viscosity (again not for gas), as explained in this thread.

But yeah, the screenshot shown makes sense with ONI physics rules. Changing that behavior would break a whole lot of things that rely on existing physics rules.

[Prince Mandor]

1 minute ago, Fradow said:

there is pressure for liquids

As you can see, it is not pressure, it is effect of mass

Yes, all this effects and beautiful graphics was made to imitate pressure, viscosity, tension and lot of other real life things. But inside this is just mass and temperature

[rgduck]

On 8/4/2021 at 4:08 AM, Fradow said:

Small nitpick on that part (the rest is correct): there is pressure for liquids (not for gas) in the game, which can break tiles, as explained on the wiki, and there is viscosity (again not for gas), as explained in this thread.

But yeah, the screenshot shown makes sense with ONI physics rules. Changing that behavior would break a whole lot of things that rely on existing physics rules.

Thanks Fradow! Yes, I think the parameters for Viscosity and MinHorizontalFlow, as described in the second thread you linked, are the numbers I was wondering about. Maybe I'll look into whether I could write a mod to change those without too much trouble.

Prince Mandor, I take your point about how the "one element per cell" rule maintains the bubble. That rule gets broken for liquid trapped at the bottom of a gas, so you don't see 3-ft water droplets persisting on the floor of air-filled rooms, but they didn't implement the reverse for gas trapped at the top of a liquid. I understand now why that would be a big change, and how it wasn't a good example for the point I was trying to make. [Edit: nope, I was wrong about this too.]

[Prince Mandor]

8 hours ago, rgduck said:

Thanks Fradow! Yes, I think the parameters for Viscosity and MinHorizontalFlow, as described in the second thread you linked, are the numbers I was wondering about. Maybe I'll look into whether I could write a mod to change those without too much trouble.

Prince Mandor, I take your point about how the "one element per cell" rule maintains the bubble. That rule gets broken for liquid trapped at the bottom of a gas, so you don't see 3-ft water droplets persisting on the floor of air-filled rooms, but they didn't implement the reverse for gas trapped at the top of a liquid. I understand now why that would be a big change, and how it wasn't a good example for the point I was trying to make.

What do you like to happens in this situation?

There are bauble of gas. It cannot move up -- all three upper cells filled with tiles. It cannot move down, because in this game gases moves up in liquid. It cannot move left or right -- it can be achieved only by swapping places with liquid, and if 10 mcg of gas will moves around ton of water then it will be cheapest method to move a tons of water.

What is ideal scenario you see here?

[Zarquan]

15 hours ago, rgduck said:

Prince Mandor, I take your point about how the "one element per cell" rule maintains the bubble. That rule gets broken for liquid trapped at the bottom of a gas, so you don't see 3-ft water droplets persisting on the floor of air-filled rooms, but they didn't implement the reverse for gas trapped at the top of a liquid. I understand now why that would be a big change, and how it wasn't a good example for the point I was trying to make.

The 3 foot of water rule actually continues to exist with small puddles.  While visually it looks like it is low to the ground, the game treats 33 grams of water on the floor as taking up 1x1 meters of space.  You can see this more clearly if you pour salt water on the ground then put fresh water on top of it.  Air does not flow through the visual area above the liquid.

[rgduck]

3 hours ago, Zarquan said:

The 3 foot of water rule actually continues to exist with small puddles.  While visually it looks like it is low to the ground, the game treats 33 grams of water on the floor as taking up 1x1 meters of space.  You can see this more clearly if you pour salt water on the ground then put fresh water on top of it.  Air does not flow through the visual area above the liquid.

Good point. I was fooled by the appearance.

9 hours ago, Prince Mandor said:

What is ideal scenario you see here?

I guess my ideal would be for ONI to not have the one-substance-per-tile rule.

But short of that increase in complexity and change ingameplay, I'd want the gas trapped at the top of a liquid to act the way a liquid trapped at the bottom of a gas does now. So visually it would flatten out along the top and then it would gradually leak out towards the side that's open. But I can already see how that would create problems. You'd have to fill in the bottom part of the cell with the color of the liquid below, and that would mislead the player about how much liquid was there. I don't think what I'd like can be done without breaking the one-substance-per-tile rule.

Really though, I don't feel strongly about the bubbles and I should have offered a different example. It's the speed at which liquid flows that I'm mainly responding to. I just thought the bubble was produced by the same mechanic.