pleroy

I believe that this is a well-know annoyance of the stock contracts with Principia. They are based on 2-body mechanics (a.k.a. conics) and don't work well in the presence of more complex trajectories. I also believe that KerbalismContracts plans to support more realistic contracts that would work well with Principia.

The FAQs explain how to report bugs. Note that on Linux you'll need version 8 of libc++ and libc++abi. Since Xenial is fairly old, these libraries may not be installed on your system.

This one looks hard. I have just updated the issue above with what we found so far, and I'll keep doing that periodically in case anyone is interested.

This is very likely to be the same bug as in issue 2507, which will be fixed in Fubini. The funny thing is that this bug (which is quite subtle) has been with us for years, and we suddenly got three reports in the last month. Either people are playing with Principia more, or some change in KSP or in some other mod causes the bug to trigger much more frequently.

Are you in China? If you are, you'll need a QQ or WeChat account. Chances are that you have one already. If you are not in China, why the hell do you want to download from that site?

It seems that the max_radius has changed for a number of celestials. Everything counts as a change, we need a way to unambiguously detect the stock system.

@R-T-B: Note that the Kerbol system has changed in 1.9, so your Principia won't recognize it and won't stabilize the Jool system. Expect to see planetary collisions after a few days.

Yes

@viktor19: Google Drive works too: just upload a save and post the link here.

It is conserved across time warp: the motion is completely continuous when warping and unwarping. This makes it possible to do spin stabilization but also more exotic rotational motions (we've played a lot with the Джанибеков effect in our tests). When resources move around the ship (or when the ship changes form), the masses and positions of parts change and Principia recomputes the moment of inertia; it then adjusts the angular velocity to preserve angular momentum (basically what figure skaters do). In essence, Principia is the source of truth for the angular momentum and it will correct what is done by KSP/Unity to make the motion physically correct.

So @AloE I understand what you are trying to do, but I am not sure what I am seeing on these pairs of screenshots: what is on the left and what is on the right (I noticed different planet names and obviously different illumination)?

Hmm, it does the same for me. But then when I go to Weiyun it tells me that the sharing link is indeed https://share.weiyun.com/5uxy0OG. Maybe they are having problems. Can you try with the non-Weiyun links (they go to Google Drive so may be hard to access in China)?

These are not the logs we need.

Good to hear that you managed to make things work on 16.04, and thank you for reporting it. I just updated the links for Fréchet on github. Announcement coming in a few minutes.

There is a configuration file for that. There was also a discussion earlier on this thread.

It exists in 18.04.1.

The reason why it's not going to happen is that we need a recent version of Clang and libc++ to build Principia. Essentially, we need complete support for C++17. The version of libc++ that shipped with Xenial was 3.7, where they had hardly started looking into C++17. We don't, at the moment, have complete C++17 support on MacOS (that only came with Catalina) and having to emulate the missing bits is a royal pain in the neck (and hampers development of useful features). That wouldn't help you. You'd need a Xenial version of libc++ version 8, or it would not even compile.

The oldest binary that supports 1.6.1 is at bit.ly/2CWdvdo. You're on your own, though: we upgraded past Xenial (16.04) in June 2017 so if a binary produced after that date works on Xenial, it's pure luck. Recent versions of Principia want libc++-8-dev and libc++abi-8-dev, and I am not aware that these would be available before Bionic (18.04).

As mentioned on the reddit thread, there is one thing that is noticeable in your log: From the forum thread, the supported versions are: Either you are using an ancient version of Principia that is no longer supported, or your crash is expected, since 1.4.5 is anterior to the earliest supported version. I suggest that you upgrade to a more recent version of KSP (1.4.5 is more than a year old), and download the latest greatest Principia (Fourier). If the problem persists, please report a bug as described in the wiki. We are interested in hearing about problems but we cannot debug them if we don't have the required information.

The geopotential data also comes from astronomical sources (and is consistent with astronomical conventions). This file has all the references for the sources that we used. The RSS textures may or may not match that, but if they don't it just mean that they are inconsistent with astronomical reality.

@AloE I wouldn't be surprised if the RSS textures were improperly aligned or even mirrored. Other than the Earth and the Moon, where it's easy to check for consistency, most users wouldn't notice this kind of glitches. In the Principia data files, the axis directions, mean radii, reference angles and angular frequencies are from "Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009", Archinal et al., http://astropedia.astrogeology.usgs.gov/download/Docs/WGCCRE/WGCCRE2009reprint.pdf. So we didn't invent our own conventions, we just followed established astronomical conventions. ETA: The values given in our files are for JD 2451545.0, i.e., 2000-Jan-01 12:00:00.0000 TDB.

@AloE You are in unexplored territory here, but chances are that what you are doing is going to work. The reason is that Principia stops managing vessels (or vehicles or Kerbals, etc.) when they are in contact with the ground. So by putting your vessel on the ground on Mimas you are not doing anything that interacts with the Principia state. And once you launch it, sure enough, Principia is going to manage it as it should. The problems mentioned in older posts had to do with people who wanted to move their vessels in flight. That is surely not going to work.

Yes, you'll need to write a suitable configuration file.

Well, this is not how bugs get fixed I have created #2313 to track this bug.

It crashes for me too...