The war against lag: Anti-lag fairings

[Psycix]

While sending up another huge floppy space station component, flailing around in <1 FPS on top of more Mainsails than anyone is supposed to use, it hit me:

We don't have to render and emulate physics of parts inside fairings.

Now of course we all love the Procedural Fairings mod, something that should become stock immediately in my opinion.

This idea would expand on that, making them more useful and providing a real solution to a very difficult problem (game performance).

How it works:

Parts inside a fairing are not rendered (optional), nor physics emulated. (Perhaps they don't even exist at all, until spawned when the fairing opens.)

The weight of the parts is calculated into the fairing base. Of course the center of mass shifts accordingly. (Don't forget angular inertia as well.)

Because of this, the fairing is a perfect substitute for the parts, it physically represents all of them - in one single physics entity.

Effects of doing this:

-A 1000 part "thing" can be sent up by a huge lifter without any lag. (No longer plagued by physics lag, now we can launch anything.)

-The fairing "protects" the part from structural failure as a result of wobbling or G-forces. (For realism, you can think of the parts being structurally attached to and supported by the fairing.)

-Less flailing, wobbling, wiggling and whatnot that makes attitude control a PITA. (We can actually steer.)

-There is a good reason to use fairings other than aesthetics. (I want to use pretty fairings, but they waste performance.)

I will repeat, that with lag out of the way:

Now we can launch anything.

EDIT:

Summary of the conclusions made in 10 pages of discussion:

It seems to be the best option to simply freeze the physics of the payload. Unity can do this, and unfreezing should not give any problems (It also happens on launch start and exiting timewarp.)

The following measures address the issue of the payload not breaking under stress, which is a result of the physics freezing:

-The fairing supports the payload. In real rockets, a stack of satellites or landers are not bearing eachother's weight, there are supports that carry each module. In KSP we cannot properly do this because of the parts only attaching in a tree.

-The fairing has extra weight, roughtly equivalent or more to what you would normally spend on struts and girders.

-The fairing is breakable. Physics inside are resumed when it breaks.

-Excessive G-forces or jerk will break the fairing base. Adding more struts will not help.

EDIT2:

Ubiozur's welding tool is capable of welding parts together as one rigid body. This might be the most viable way to realize anti-lag fairings.

Edited November 21, 2013 by Psycix

[Synapse]

Nothing to add, implement this

[Hiddos]

Definite yes.

[42undead2]

But then it would have to load it once the fairings were separated, and that could take a big chunk of time, depending on the amount of parts under there.

[DMagic]

I think it's a good idea, too, but I'm also pretty sure this is on the do not suggest list (it's a variation on the combine-parts suggestion) because it's been suggested a thousand times.

There are a few obvious problems with this. If you don't load the parts inside the fairings at launch then you will have to load them at some later point. So you will have some 10 to 20 second hitch when you separate the fairings and all of the parts have to be loaded in. Which would be a little odd, but not that big of a deal.

The other issue is that no, you can't launch anything and expect good performance. A space station with a 1000 parts will still have slow performance whether you load those parts at launch or in space. If you are building a station out 10 or so components then the launch would be a little smoother since you are only simulating the launcher parts, but once you combine everything in space you would have the same problems as always.

[woppeldopple]

Very bad idea. You want to disable all the phyics within your magic bobble leading to the ability to launch the most rediculous constructs to space that normally would completely distort the rocket and everything else?

What about torsion forces and inertia of your giant part? The fact its stable in space doesn't mean it is stable during launch with high G-stress.

This would completely destroy the idea of KerbalSpaceProgram.

What you want is a magic cheat box to bring your too big constructs with a too slow computer in orbit - the thread should be renamed accordingly.

Just use docking!

You cannot launch anything.

Edited July 31, 2013 by woppeldopple

[MainSailor]

IIRC the Fairing Factory generator website that includes a DLL that struts anything attached to the fairing base. Unfortunately I never use FF parts since the fairings and base themselves are quite heavy.

[leopardenthusiast]

blah blah blah

You still have to make a launch vehicle capable of lifting the payload's mass, and your payload is going to be strutted to hell and back no matter what. Sure, there's the problem of the payload's drag being lost, but that's what fairings do. Since it was stated in the OP that the base would get the payload's mass, your launch vehicle would be pretty much exactly the same. Only your payload would be affected, and only until you popped the fairing open.

[woppeldopple]

You still have to make a launch vehicle capable of lifting the payload's mass, and your payload is going to be strutted to hell and back no matter what. Sure, there's the problem of the payload's drag being lost, but that's what fairings do. Since it was stated in the OP that the base would get the payload's mass, your launch vehicle would be pretty much exactly the same. Only your payload would be affected, and only until you popped the fairing open.

What does blah blah mean? Do you shut your eyes and ears because you cannot bear the truth? What you said has nothing to do what i said ... oh you dont know what i said, forgot it for a second!

Or you did not understand? Well In both cases: read it again ^^

[leopardenthusiast]

What does blah blah mean? Do you shut your eyes and ears because you cannot bear the truth? What you said has nothing to do what i said ... oh you dont know what i said, forgot it for a second! ^^

I cut out your post because there's only one post after it before my post. I rate your trolling attempt at a 2/100.

[woppeldopple]

I cut out your post because there's only one post after it before my post. I rate your trolling attempt at a 2/100.

Oh dear... ... one more hint: Of course your launching vehicle is not necessarily the same! Replacing a complex construct with a point mass is not the same.

[Themohawkninja]

I cut out your post because there's only one post after it before my post. I rate your trolling attempt at a 2/100.

Don't start a war XenonBlade. Debate with logic not troll calling.

OT: Would the fairing's volume match that of the station? What about attachment nodes (you can't expect that one centered rocket cluster is going to be the key, sometimes spreading the thrust over a wide area works too). Lastly, how would you make sure that the hatches work when they are all connected? The weld mod's creator stated that he hasn't don't welded Hitchhikers, because he doesn't know how to get the hatches to work properly.

[Psycix]

I think it's a good idea, too, but I'm also pretty sure this is on the do not suggest list (it's a variation on the combine-parts suggestion) because it's been suggested a thousand times.

I think the intention behind that is not to suggest new parts which are combinations of others, like an engine attached to a fuel tank.

There are a few obvious problems with this. If you don't load the parts inside the fairings at launch then you will have to load them at some later point. So you will have some 10 to 20 second hitch when you separate the fairings and all of the parts have to be loaded in. Which would be a little odd, but not that big of a deal.

But then it would have to load it once the fairings were separated, and that could take a big chunk of time, depending on the amount of parts under there.

Only if the developers choose to spawn the parts on sep. You could also have the parts existing, simply sitting there without physics.

Another option might be to have the parts loaded in a cache.

Long story short there will be multiple ways to do this, and it's up to the developers to determine which is best.

The other issue is that no, you can't launch anything and expect good performance. A space station with a 1000 parts will still have slow performance whether you load those parts at launch or in space. If you are building a station out 10 or so components then the launch would be a little smoother since you are only simulating the launcher parts, but once you combine everything in space you would have the same problems as always.

True, it's just for the launch. I said: We can launch anything. Not play anything.

There's more to it than just space station components. This will also be useful for rovers, landers, or other contraptions.

Very bad idea. You want to disable all the phyics within your magic bobble leading to the ability to launch the most rediculous constructs to space that normally would completely distort the rocket and everything else?

What about torsion forces and inertia of your giant part? The fact its stable in space doesn't mean it is stable during launch with high G-stress.

This would completely destroy the idea of KerbalSpaceProgram.

What you want is a magic cheat box to bring your too big constructs with a too slow computer in orbit - the thread should be renamed accordingly.

You do not seem to understand how the fairing substitutes for the mass, CoM and angular inertia.

Of course I could replace these fairings for a gazillion struts, but it's not pretty, not realistic at all and certainly not beneficial to the gameplay. I feel KSP is about launching stuff and then using it up there, not strutting the crap out of something until the rocket is stable enough to go up.

[Psycix]

Post to react to Themohawk (can't edit since my previous is being moderated)

OT: Would the fairing's volume match that of the station? What about attachment nodes (you can't expect that one centered rocket cluster is going to be the key, sometimes spreading the thrust over a wide area works too). Lastly, how would you make sure that the hatches work when they are all connected? The weld mod's creator stated that he hasn't don't welded Hitchhikers, because he doesn't know how to get the hatches to work properly.

Of course the volume matches it, just like procedural fairings does: First screenshot for procedural fairings thread

For wider payloads and lifters, there are larger fairing bases. (procedural fairings has quite big ones)

What do you mean with the hatches?

Oh dear... ... one more hint: Of course your launching vehicle is not necessarily the same! Replacing a complex construct with a point mass is not the same.

It is. Learn physics

A rigid body consisting out of multiple sub-bodies that have mass can be modeled like a single point perfectly. The point would be at the collective center of mass, with the collective mass. And next to that you need to define the angular properties as well.

If executed properly you will not be able to tell the difference between a normal fairing and a magic fairing. (aside from the lag)

[tntristan12]

Despite being a total jerk about it, woppel raised a pretty valid argument against this concept. The fact that a fairing is placed around the object doesn't mean that structurally, it can handle the stresses of launch. Though you could make the assumption that anything inside the fairing is strutted to hell and back, it does make it seem a bit like a cheat to get around launching unstable structures.

There's also the issue of mass distribution. If you store the mass, but not necessarily the location, you make it possible to cheat lifting highly irregular masses by putting a fairing around them. A possible solution to that would be to simulate the location of the center of mass of the fairing, which is not possible if the mass is constrained to the fairing plate.

Edited July 31, 2013 by tntristan12

[Mr. Scruffy]

If possible, the idea deserves consideration, i think.

I mean, if you imagine that the interior is well fixed to the fairing itself, then, shouldnt it even be considered one part for realism sake, more than not? Inside the fairing nothing should break off due to drag. Maybe due to high g-forces, but if you think of the whole interior filled with airbags or styrophor...

The payload parts should still be loaded pre-launch, just not simulated physically before the fairing opens - their position is fixed relative to the fairings base, until it opens.

I think ´we can launch anything´ is a gross overstatement, though. It should reduce lag during launch, not more, really, and the extent to which it would do that would depend on how many parts your payload contains compared to the rest of the rocket. Detail lovers would benefit most, i´d guess, as it would speed up the launch of high-part-count-payload launches while not making it to more easy to lift heavy stuff.

[Themohawkninja]

By hatches I mean the "doors" that allow Kerbals to go in and out of command pods/Hitchhikers.

[Psycix]

Though you could make the assumption that anything inside the fairing is strutted to hell and back, it does make it seem a bit like a cheat to get around launching unstable structures.

Perhaps the weight of the fairing can make up for this advantage.

There's also the issue of mass distribution. If you store the mass, but not necessarily the location, you make it possible to cheat lifting highly irregular masses by putting a fairing around them.

Read the first post, this is all accounted for.

I think ´we can launch anything´ is a gross overstatement, though.

It is. (Intended as a joke.)

The idea behind it though is that it allows us to focus on the actual gameplay (building rockets, launching stuff, doing stuff with that stuff) rather than spending hours strutting everything until it works.

[providus]

It is. Learn physics

A rigid body consisting out of multiple sub-bodies that have mass can be modeled like a single point perfectly. The point would be at the collective center of mass, with the collective mass. And next to that you need to define the angular properties as well.

If executed properly you will not be able to tell the difference between a normal fairing and a magic fairing. (aside from the lag)

I can gurantee you its not the same, sorry. But right now im too lazy to explain it, but this is very basic physics - i assume it won't be that hard to find information about it.

Cannot support this suggestion, the game would be messed up. If your therory were right (and it is not) then every rocket could be replaced by one part. Think about it, it is the same?

And yeah, the total mass is the same this is right. But physics is more than the attribute mass...

Edited July 31, 2013 by providus

[TheCanadianVendingMachine]

What does blah blah mean? Do you shut your eyes and ears because you cannot bear the truth? What you said has nothing to do what i said ... oh you dont know what i said, forgot it for a second!

Or you did not understand? Well In both cases: read it again ^^

Right, two things

1 - "Blah Blah Blah" is a term used by most posters to show that the previous wasn't stuff they were replying to

2 - If you were to implement the idea, what would happen once you open the fairings? The whole craft would have to render causing lag. So the idea would be cancelled out once you open them.

[chaos_forge]

Providus is correct in saying that it's not the same . . . you can replace it with a point mass for center-of-mass calculations, but the moment of rotational inertia for the rocket would be incorrect.

That said, this is a game, and I think this idea would make the game more fun. More realism isn't always better.

[woppeldopple]

That said, this is a game, and I think this idea would make the game more fun. More realism isn't always better.

It would ruin the game. Physics simulation is a core feature of KSP and you want to disable it?

Im very sure Squad will never do such a ... folly.

Did you consider the slight possibility that your computer is not powerful enough when you cant have fun due to laggyness? But this is no reason to truncate KSP!

KSP is alpha btw. Usually optimization is low priority. Im sure we will see performance patches in future!

Edited July 31, 2013 by woppeldopple

[chaos_forge]

Did you consider the slight possibility that your computer is not powerful enough when you cant have fun due to laggyness? But this is no reason to truncate KSP!

That's a bit of an elitist stance . . . And I don't think the loss of realism would be great enough to justify saying this one little change would "ruin the game"

[tntristan12]

I will say this in favor of the idea: it would finally allow us to build high-part-count payloads and the high-part-count launchers to launch them, making the concession of allowing us to load the payload later... And just because of that I support this idea, even if it does make fragile payloads nigh invincible during launch. Maybe doing this would actually expand player creativity, and that can never be a bad thing!

[woppeldopple]

That's a bit of an elitist stance . . . And I don't think the loss of realism would be great enough to justify saying this one little change would "ruin the game"

Elitist? No. Technically obvious? Yes. Have a sober look at it - i can affort high end harware neither.

Perhaps you underestimate the consequences of the cheat-fairings by far and more than that you can not appreciate KSP like it is.

KSP is far away from being a simulation. Truncating basic physics means completely destroy all the "realism" we have.

@tntristan12: Sadly i have no clue what you mean. Can you explain again please? You dont "launch" anything. You cheat it in space.

Edited July 31, 2013 by woppeldopple