[WIP][1.8.1, 1.9.1, 1.10.1, 1.11.0–2, 1.12.2–5] Principia—version ‎‎Kronecker, released 2024-11-01—n-Body and Extended Body Gravitation

[KAO]

Forgive me if this has been addressed previously, but will Principia work out of the box with Real Solar System/Realism Overhaul? or is some tweaking of the configs required?

[Phineas Freak]

@KAO Principia was more or less created with RSS in mind, since it is a solar system that is known to be stable over large time periods. Other solar systems (including the stock one) 99% of the time are not stable, requiring extensive rework. So, it is assured that Principia will work with the RSS/RO/RP-0 suit of mods.

Edited July 31, 2017 by Phineas Freak
Typo...

[panourgue]

Does anyone know how can I re-enable left click menus in map view ("display patched conics" option not doing it)?

Or, even more importantly, this one:

Going to the Tracking Station or using haystack just to switch vessel?

Edited August 2, 2017 by panourgue
a

[eggrobin]

4 hours ago, panourgue said:

Does anyone know how can I re-enable left click menus in map view ("display patched conics" option not doing it)?

There is no way to do this, this UI comes with classes that Principia has to disable for things to work properly.

However, it provides replacements for all of those, see also the documentation on the subject.

4 hours ago, panourgue said:

• Principia does not support setting a celestial body as a target (since it has frame selection for interplanetary flight planning instead), but the option is provided under "KSP features" for use with other mods that require it, e.g. MechJeb. Click on "Select target celestial...", then click on the celestial.
• To focus view on a celestial body, simply left click on it.

5 hours ago, panourgue said:

• Principia comes with its own flight planning system; create manoeuvres there, and warp to them using the relevant button in the flight planning UI.
• Unfortunately it does not yet provide a tool to warp to an arbitrary point on the trajectory, but that can be worked around by making a flight plan, and putting a dummy manoeuvre at the desired point.

5 hours ago, panourgue said:

• To target a vessel, click "Select target vessel...", and click on the vessel.
• To switch to a vessel, target it, and press the "Switch To" button.

[Parafaragarmus]

I'm not sure if this has been discussed before but I seem to be having trouble when going to land on the Moon. Principia was the only mod I added before I started having the problem. I started using Principia with RSS/RO/RP-0 and it's been working great but last night I went to land a probe on the surface of the Moon and as I got near the surface the whole thing was vibrating up and down. My first couple attempts the probe clipped through the ground and got destroyed.I made sure I had the latest version and tried again. The surface was still vibrating wildly but my craft didn't clip through the ground. It kept bouncing off the surface until the whole thing was destroyed. I also noticed at about 60km up when timewarping there is a noticeable drop in altitude depending on the speed of the timewarp. I think I saw a change of ~1.5km. I'm not sure if it's something I'm doing wrong to cause it.
Thanks

Edited August 6, 2017 by Parafaragarmus
typos

[goldstarstickergiver]

Yeah I had the same issue with the moon. There was about 150-200m discrepancy between what mechjeb/visual observasion gave as the altitude and the point at which the craft impacted. Removed principia and it fixed the issue. Which is a shame cos it's an awesome mod. 

[eggrobin]

13 hours ago, Parafaragarmus said:

I'm not sure if this has been discussed before but I seem to be having trouble when going to land on the Moon. Principia was the only mod I added before I started having the problem. I started using Principia with RSS/RO/RP-0 and it's been working great but last night I went to land a probe on the surface of the Moon and as I got near the surface the whole thing was vibrating up and down. My first couple attempts the probe clipped through the ground and got destroyed.I made sure I had the latest version and tried again. The surface was still vibrating wildly but my craft didn't clip through the ground. It kept bouncing off the surface until the whole thing was destroyed. I also noticed at about 60km up when timewarping there is a noticeable drop in altitude depending on the speed of the timewarp. I think I saw a change of ~1.5km. I'm not sure if it's something I'm doing wrong to cause it.
Thanks

9 hours ago, goldstarstickergiver said:

Yeah I had the same issue with the moon. There was about 150-200m discrepancy between what mechjeb/visual observasion gave as the altitude and the point at which the craft impacted. Removed principia and it fixed the issue. Which is a shame cos it's an awesome mod. 

This sounds like RSS issue 111 (see also Principia issue 1346 linked in that thread). It was fixed in June, but there has been no RealSolarSystem release since, so unless you download the latest configs from GitHub you will not get the fix. I think a RealSolarSystem release (targeting 1.3) is planned before the Чебышёв release (2017-08-21).

CC @NathanKell who might have something to add.

[Cristi]

I can confirm the bounciness + small clipping on moon and Europa (these are the only bodies I tested) with and without BetterBurnTime. I'm using the quarter size RSS version 1.0 which is made for 1.3.0 so I'm not sure what is the cause.

Huge thank you for all the work you guys are putting into this mod !!

Edited August 7, 2017 by Cristi

[eggrobin]

9 minutes ago, Cristi said:

I can confirm the bounciness + small clipping on moon and Europa (these are the only bodies I tested) with and without BetterBurnTime. I'm using the quarter size RSS version 1.0 which is made for 1.3.0 so I'm not sure what is the cause.

Huge thank you for all the work you guys are putting into this mod !!

This is unrelated to targeting 1.3 or 1.2.2, it is about the configs for the celestial bodies having a timewarp limit below the surface where you land, see also the issue I linked (it simply happens that the next RSS release will target 1.3, which is why I mentioned the version number).

[NathanKell]

13 hours ago, eggrobin said:

This sounds like RSS issue 111 (see also Principia issue 1346 linked in that thread). It was fixed in June, but there has been no RealSolarSystem release since, so unless you download the latest configs from GitHub you will not get the fix. I think a RealSolarSystem release (targeting 1.3) is planned before the Чебышёв release (2017-08-21).

CC @NathanKell who might have something to add.

Guilty as charged, yes.

[Parafaragarmus]

Thanks for pointing me in the right direction. Everything is working great now.

[Cristi]

@Parafaragarmus what exactly you did to solve it?

Thanks in advance.

[eggrobin]

For the new moon (lunation number 218), which is a total eclipse, the new release (Чебышёв) is out.

The speed of the plotting of histories has been improved by about an order of magnitude. The slow plotting in previous versions was responsible for most of the slowdown in map view. Further, the predictions are now plotted smoothly even when they are integrated with a large tolerance.

The flight plan now supports burns that guide themselves to follow the Frenet trihedron, e.g., tracking the tangent (prograde), or the binormal (the normal to the orbital plane). Select "Inertially fixed" in the flight planner to use an unguided burn instead, e.g., for spin-stabilized burns.

For the first time, Principia supports two versions of KSP: downloads are available for 1.3 and for 1.2.2. Make sure you download the right one (if you don't, the game will crash on load).

A couple of bugs reported by @panourgue and @scimas were fixed.

See the change log for details.

Thanks to @Iskierka and @Jim DiGriz for testing the Linux and Macintosh builds respectively.

Note to RSS users: Principia correctly simulates the motion of the moon, so the eclipse occurs as expected when using Principia, even after more than 66 years of numerical integreation, see below. Conversely, without Principia, the Moon's motion cannot be simulated with the requisite accuracy to get correct eclipses, since it is a heavily perturbed orbit.

 

[drtedastro]

Really great work.

Thanks to all working on / with this.

Cheers and happy eclipse.

[Cristi]

Quote

The speed of the plotting of histories has been improved by about an order of magnitude. The slow plotting in previous versions was responsible for most of the slowdown in map view. 

Amazing work guys, I can confirm that plotting, map and Space Center views are much much smoother. 

[Scotskerb]

I was thinking about the bit about there being no guarantee that Principia will work with any given planet pack, so I decided to create a patches pack to put bodies with unstable orbits into more stable ones, usually around different host bodies than before. The thread for this pack can be found here.

Edited September 21, 2017 by Scotskerb

[hypervelocity]

I am trying this mod for the first time as I just managed to switch from RO RSS RP-0 @ 1.1.3 to the same @ 1.2.2. However, I have been following its development since it came out and it has been blowing my mind ever since (even tho I had never played it!)

I just wanted to say THANK YOU! There are people here in these forums that simply amaze me.

Many thanks for this and all your efforts

Edited September 5, 2017 by hypervelocity

[lyttol]

Please can someone explain how to make principia (Чебышёв) play nicely with Realism Overhaul for ksp 1.2.2

I was blown away seeing the multi-body gravity modelling, and it hit me viscerally that we don't live in a cute predictable universe, a deep shift in my felt awareness which I don't normally get from playing games, so thank you for this amazing mod.

I have the same problem with bouncy moon landings described a few posts up, and tried "force stop" principia described above, but it didn't help. If I remove Principia and reload the game before landing, it did seem to be better... I understand that the problem is something to do with "timewarp limit below surface" and that its fixed in RSS for 1.3, but not being a technophile, I don't know how to "download the latest configs from GitHub to get the fix", and the RO update for 1.3 still seems a while off.

Again, thanks for the amazing work on this mod, its very exciting. Now I just wait for RealISRU to get taken up by someone... *smile*

Thanks to everyone in the community that supports this amazing project!

Edited September 11, 2017 by lyttol

[panourgue]

9 hours ago, lyttol said:

don't know how to "download the latest configs from GitHub to get the fix"

You need to replace file "GameData/RealSolarSystem/RSSKopernicus/Earth/Moon.cfg" in your game folder with the newer version. Just download the whole RealSolarSystem repository (press green button) and take the file from there

[lyttol]

Thanks panourgue, I can do that Do we know if there are any other configs that also need to be updated?

[nanomage]

Phobos has the same issue as well, actually I would expect all non-atmospheric bodies to have it. I don't think they are all fixed in RSS 1.3. Phobos for example has

timewarpAltitudeLimits = 0 200 1500 2500 20000 50000 60000 100000

given the actual dimensions, per wiki, of 27 × 22 × 18 km and the mean radius of 11.2667 km, you would probably want something more like

timewarpAltitudeLimits = 0 6000 10000 15000 20000 50000 60000 100000

to avoid being managed by principia on touchdown, especially if landing close to the longest axis.

 

[hypervelocity]

Hey guys, I have a question for you all savvy Principia players/devs - is there any way to cheat an object into orbit? I am porting my old 1.1.3 Carreer Save which has a lot (A LOT) of hours invested into it, with several crafts, vehicles & infrastructure all across the Solar System and a lot of science points gained and contracts won.

I would like to carefully place my most useful/relevant craft in the places they were in 1.1.3 but I noticed 1.2.2 Cheat Menu only gets me to LEO (tried changing orbit parameters with no success) and Hyper Edit does not work - any way to sort this out?

Many thanks in advance!

[scimas]

On 13/09/2017 at 8:24 PM, hypervelocity said:

Hey guys, I have a question for you all savvy Principia players/devs - is there any way to cheat an object into orbit? I am porting my old 1.1.3 Carreer Save which has a lot (A LOT) of hours invested into it, with several crafts, vehicles & infrastructure all across the Solar System and a lot of science points gained and contracts won.

I would like to carefully place my most useful/relevant craft in the places they were in 1.1.3 but I noticed 1.2.2 Cheat Menu only gets me to LEO (tried changing orbit parameters with no success) and Hyper Edit does not work - any way to sort this out?

Many thanks in advance!

As far as I understand, principia takes full control of the physics from stock KSP, except for vessels in atmosphere or close to the surface of bodies (see the timewarpAltitudeLimit issues above) and doesn't allow anything else to change vessel orbits. The only thing I can suggest is to remove principia from your installation, launch KSP and get your vessels into the orbits you want, using cheats menu or hyperedit or whatever else you prefer. Then add principia again to the installation and continue playing. 

There is a problem with this approach though. You might find some ships going on vastly different routes compared to where you placed them. This is because a lot of high orbits in stock kerbal system are not as stable when you take into account the gravity of other bodies. 

Spoiler

 

See the above image as an example of what happens when you try to complete satellite contracts near Duna. 

Also, if you have any vessels landed at high altitudes on non atmospheric bodies, they might just explode when you try to take control of them (again the timewarpAltitude issue.) 

And apologies if there are formatting issues, posting this from mobile. 

[hypervelocity]

many thanks for your reply @scimas, I actually did not think of this approach before!

I am playing in RSS so I don't think I will have the aforementioned issues -> I will try removing principia and placing my crafts using cheats/Hyperedit and will comment on the results!

have a great day and thanks for the help!!!

[TranquilTempest]

If I want to change the mass of the star, is there somewhere in addition to the kopernicus config file I need to change it? Or is there a cache file I need to delete so the initialization works properly?  When I create a game after making the change, all the planets have extremely eccentric orbits, even if I set their eccentricity to zero in the config file.  

 

Edit: I found the principia config files.  Do I need to manually re-generate the initial state cfg? 

Edit2: Editing the gravitational model, deleting the initial state cfg, and force stop then restarting principia worked. 

Edited September 17, 2017 by TranquilTempest