What ARE rings?

[uxuser]

I was on the wiki and I wanted to look at Jool, Now, I didn't know this but I spelled Jool, Gool. Now I started and I saw in the list, Gas Planet 2! So I clicked on it and I saw it would have rings! Now I just watched Ender's Game, And the rings were like, A really icy, oblate planet! (Without a center orbiting this blue gas giant) So I thought about Ksp and I think you should actually be able to land on it, it would only have a like, .2 of Kerbin's gravity or something so it has like, No gravity! So yeah this would be cool . Also, This is my first post and please don't be hurtful. Thanks! Be cool!

Edited November 12, 2013 by uxuser

[astropapi1]

Like Saturn.

[LtHeckard]

Well, Gas planets don't have a surface. Think of a gas planet as a planet entirely made of clouds, No land at all. Welcome to the forum!

[vexx32]

Rings in the real world are typically a great many tiny pieces, made up of rock and/or ice among various other things.

A "solid" ring is, to the best of my knowledge, not actually possible. A solid mass like that would be inherently unstable as far as I can reasonably take a guess at this early in the morning. There would be constant stress forces on the ring in all directions due to the gravity, and the shear forces caused at pretty much all angles should cause a mass like that to disintegrate -- and that's ignoring the impossibility of it ever even forming in the first place. In order to be even remotely stable, the ring would have to be perfectly balanced in every way, and spinning at extremely high speed, I would think. The slightest instability would cause it to disintegrate, at the very least, due to a difference in the gravitational force from the planet on certain sections of the rings.

[tetryds]

a KSP ring could be just like a lot of scatter, but in orbit

idk if there is any need for it to be collideable

so, no physics for it, they would be just on rails graphics, and our gpus arent doing much on ksp atm

there is no problem in spamming asteroids as scatter into a ring shape

[r4pt0r]

i would think that they could be physical collidable masses, but would not register a gravity per say. i think if they were implemented like that though they should add a spiked landing gear that locks you into the ground sort of, for probes or what not.

of course they would all be locked in their orbits no movement reletive to eachother

Edited November 12, 2013 by vexx32
Merged posts.

[allmappedout]

vexx is right - a ring of any thickness lateral to the planet would have extremely strong tidal forces acting on it which would very quickly tear it apart, if it could even form in the first place. Something like the Halo in...Halo...would actually work better as it is thin in depth, and so the gravity gradient between the furthest point and the closest point is far lower. Obviously constructing something like that is unfeasible for any of us, but the theory is sound.

[Dunbaratu]

Modelling a ring truly accurately as millions of separate individual bits of rock and dust each orbiting on its own would kill any home PC's CPU. You'd need a supercomputer to do it.

BUT there's a few tricks that might work to get a thing sort of like a real ring but with some realism removed to make it calculable:

1 - Make it a single solid object in the game engine. Granted a real world solid ring would be orbitally unstable and fall in (thus why Larry Niven had to write a sequel to Ringworld after fans told him he got it wrong, and his sequel includes the discovery that the ring has a system of rockets to provide station-keeping thrust for the ring to hold it in its unstable equilibrium, and the breakdown of that system was the main plot of the book). But in KSP since planets and moons always move "on rails" instead of using moment-by-moment stepwise calculations, SQUAD could design an on-rails equation for the ring's motion that just utterly defies physics and keeps the ring there.

2 - With the ring being a single on-rails object orbiting the planet, the painted texture on the object could contain a lot of transparency in it allowing you to see through the ring.

3 - To make the ring permeable so things can fly through it but will encounter dust as they do so, it's interior could be modeled as an "atmosphere" with drag. The painted texture could show a lot of specs of objects, or the scatter system could be used to show lots of rocks, but the actual slowdown isn't provided by colliding with the rocks. It's provided by the "atmosphere" drag. Here and there a few real rocks could be in the midst of the dust as separate orbiting objects.

4 - Alternatively, the ring could be "painted" with a patchwork of millions of "solid" and "not solid" sections and you have to pass through the "not solid" parts to make it through.

[kiwiak]

Modelling a ring truly accurately as millions of separate individual bits of rock and dust each orbiting on its own would kill any home PC's CPU. You'd need a supercomputer to do it.

Lets say, we want ring made from touchable and collidable pieces of rock/ice. You dont have to render all rocks that are parts of the ring.

On some distance, player woudl see just see single ring object covered by texture. And if player gets closer, game starts to randomly generate rocks that can be interacted with and that bounce from each other. If player mooves away from ring, generated ring objects are discarded. Of cource around rings, warp would work same as with atmosphere.

Still, i dont know if generating only visible part of such the ring woudl be possible on home pc.

[allmappedout]

Imagine having a 50 part space ship, or even a 20 part probe in orbit around saturn. Then imagine that you have 1.5million 1 piece spaceships/rocks within 2.5km of your position.

Imagine having to buy a new motherboard.

Anything less and people will complain it's not a proper ring. Make them too big people will complain it's not granular enough, make them too small people will complain they can't interact with it. Make it too busy and people will complain they crash into it too often.

The problem is that even after surmounting the technological issues with having rings, there's a ton of other issues which the devs will have to look into. It'll be interesting to see how they approach it.

[Dunbaratu]

On some distance, player woudl see just see single ring object covered by texture. And if player gets closer, game starts to randomly generate rocks that can be interacted with and that bounce from each other.

That's also a really good solution. Basically, use the 2.5km "full physics" limit. The ring is a non-colliding picture only. Just a see-through translucent texture on a harmless object, but when you're in it, scatter rocks start being generated within the 2.5km physics range around you, and as they pass far enough away and go "on rails", they actually just disappear entirely.

[kiwiak]

I think they will just make it impossible to approach ring on distance allowing to see indyvidual objects.. Fast mooving particles woudl be just destroying ship. Its easiest way.

[Kasuha]

Material of Saturn's rings is so sparse that if you flew through it, you'd probably not collide with anything. This was already tested with the Cassini probe which flew through one of the ring's gaps, which - you should notice - is not a place where there is no ring, just a place where the ring material is more sparse than elsewhere. Anyway - the size of the ring is enormous, the distance between innermost and outermost rings is more than distance from Earth to Moon, while mass of the rings is about a thousandth of mass of the Moon.

The ring from close up is a bit like a cloud - you can see clouds in crisp contours in the sky, but when you get close its contours become fuzzy and you can't tell where in space there is cloud and where it is not. Clouds are also made of thousands cubic meters of water but you don't become any significantly wetter by passing through a cloud.

So to get a reasonably realistic representation of a ring in the game it would suffice to have a somewhat translucent bitmap ring for views from afar and a slightly blurred line for when you're inside the ring or looking at it edge-on. No flying stones necessary.

Edited November 12, 2013 by Kasuha

[Dunbaratu]

Material of Saturn's rings is so sparse that if you flew through it, you'd probably not collide with anything. This was already tested with the Cassini probe which flew through one of the ring's gaps, which - you should notice - is not a place where there is no ring, just a place where the ring material is more sparse than elsewhere. Anyway - the size of the ring is enormous, the distance between innermost and outermost rings is more than distance from Earth to Moon, while mass of the rings is way less than mass of the Moon.

The ring from close up is a bit like a cloud - you can see clouds in crisp contours in the sky, but when you get close its contours become fuzzy and you can't tell where in space there is cloud and where it is not. Clouds are also made of thousands cubic meters of water but you don't become any significantly wetter by passing through a cloud.

So to get a reasonably realistic representation of a ring in the game it would suffice to have a somewhat translucent bitmap ring for views from afar and a slightly blurred line for when you're inside the ring or looking at it edge-on. No flying stones necessary.

Or just a few stones. Sparse enough that you are likely to make it through, but not certain so you still need to keep your eyes open and watch out and perhaps deflect a little bit.

[Kasuha]

Or just a few stones. Sparse enough that you are likely to make it through, but not certain so you still need to keep your eyes open and watch out and perhaps deflect a little bit.

Or maybe an equivalent of ground scatter, just placed in space.

[Dunbaratu]

I think they will just make it impossible to approach ring on distance allowing to see indyvidual objects.. Fast mooving particles woudl be just destroying ship. Its easiest way.

Whether the particles are fast moving or not (relative to the craft) depends on how gently you enter the ring (wow that really sounds bad). It shouldn't just automatically destroy the craft to be in the ring if you entered it at a relative velocity difference of only a few meters per second. For example, you might be in an orbit that is at the same altitude as the ring, but inclined by 0.5 degrees from it. As you pass by the ascending and descending nodes you'd drift through the ring, but not at high speed relative to the material of the ring. You and the dust of the ring are both moving at nearly the same orbital velocity, just half a degree off in direction. Similarly if you'd been orbiting at just a little bit higher than the ring and slow down a bit to bring your periapsis inside the ring, you're not necessarily encountering the ring's dust at high velocity.

[Dunbaratu]

Or maybe an equivalent of ground scatter, just placed in space.

That's a suggestion people have made in this thread. Do it like ground scatter, but make the rocks collidable instead of pass-through. Then getting it right becomes just a matter of finding the right setting for the density so it's sparse enough.

[kiwiak]

Material of Saturn's rings is so sparse that if you flew through it, you'd probably not collide with anything. This was already tested with the Cassini probe which flew through one of the ring's gaps, which - you should notice - is not a place where there is no ring, just a place where the ring material is more sparse than elsewhere. Anyway - the size of the ring is enormous, the distance between innermost and outermost rings is more than distance from Earth to Moon, while mass of the rings is about a thousandth of mass of the Moon.

The ring from close up is a bit like a cloud - you can see clouds in crisp contours in the sky, but when you get close its contours become fuzzy and you can't tell where in space there is cloud and where it is not. Clouds are also made of thousands cubic meters of water but you don't become any significantly wetter by passing through a cloud.

So to get a reasonably realistic representation of a ring in the game it would suffice to have a somewhat translucent bitmap ring for views from afar and a slightly blurred line for when you're inside the ring or looking at it edge-on. No flying stones necessary.

So.. no giant rocks infinitly bumping each other?

[uxuser]

Or maybe an equivalent of ground scatter, just placed in space.

So what I was thinking when I read this, It's a beautiful ring like saturns and when you get closer you can kinda see that it's just a bunch of ground scatter moving around the new GP2. But yeah they wouldn't have gravity and would be hard to land on one and explore and make a flag! Maybe there should be metal harpoons in Kerbal Space so you could take it and launch where you want it, Then you can reel yourself in and it would be like having an artificial gravity but really it's just pulling

you down!

I agree, But since its Kerbal Space Program, and the planets are not colored like they would realistically be. So maybe the rings need to be green or something! Idk, First thing that came to my mind...

[tetryds]

i would think that they could be physical collidable masses, but would not register a gravity per say. i think if they were implemented like that though they should add a spiked landing gear that locks you into the ground sort of, for probes or what not.

of course they would all be locked in their orbits no movement reletive to eachother

i like this idea

to avoid having too many pieces of rock, it would be cool to have less of them but make them bigger, still without gravity

also have a few kinds of rocks and repeat them all over

it would be something like the easter egg, but several and a bit smaller

anyway, stop thinking that anything will require a supercomputer, the ksp game itself would "require a supercomputer" if it didn't exist

[Kasuha]

The question is if we want it to be realistic or like in sci-fi movies. Because for realistic rings you might have one valnut-sized rock and handful of dust within the whole 2.5 km physics radius around your ship. And even that could be considered dense part of the ring.

If any effects at all, I'd vote for scatter using very small bright particles emulating the dust. Of course completely penetrable. But given the fact that Saturn's rings are only a few hundred meters thick and the ship is usually travelling at speeds of thousands meter per second you would probably see the scatter in one frame if you're lucky unless you align the ship with the ring very precisely.

[lajoswinkler]

Anyone suggesting rings made of actual objects clearly never had a lot of anything around Kerbin. Even if stuff isn't physically rendered at the moment, it will clog up your CPU.

Rings, if implemented, should be one object with fixed rotation. Transparent, foggy object with a drag value. That's the best we could hope for at this level of affordable, commercially available computer technology.

(in real world, solid rings would crumble; infinitely strong rings would wobble and crash to the surface with one part)

[kiwiak]

Penetrable, UNLESS you are moving wih hight velocity relativly to this dust. If you are, well your ship becomes penetrable

But i would like to suggest another thing, empty parts in ring structure. Like casini division

Planning your orbit to fly inside such division woudl be nice challenge.

[ziogatto]

Well I hope the rings don't just get painted or as fuzzy patches with some rendering effects but are actually implemented as something like this:

http://youtu.be/h7eREddMjt4?t=4m1s

[tetryds]

Well I hope the rings don't just get painted or as fuzzy patches with some rendering effects but are actually implemented as something like this:

http://youtu.be/h7eREddMjt4?t=4m1s

that looks pretty cool

i doubt he has a supercomputer

anyway in ksp it doesnt need that much scatter nor being collideable