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About pleroy

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  1. Hmm, this has been reported by @scimas a long time ago (#1868) but somehow it fell off our radar screen. We have code to set the markers but apparently it stopped working with some KSP upgrade. We should try to figure out what's happening.
  2. @Eriksonn: It is completely feasible, but it requires some understanding of the way geopotential modeling works. You don't directly use the altitude. Instead you specify coefficients (conventionally named Cnm and Snm) for spherical harmonics of various degrees and orders. This image gives an intuition of what the spherical harmonics look like (the poles are on the left and right, the equator is vertical on the image). For instance, degree 2 order 0 makes it possible to put more mass at the poles and less at the equator or vice-versa; degree 2 order 2 makes it possible to put more mass at Greenwich and Fiji and less in the Appalachians and Himalayas, etc. Unfortunately the Wikipedia article on Geopotential model is rather lame, so I recommend looking at section 6 of the IERS Conventions. In practice you'll need to write a custom principia_gravity_model configuration covering (at least) the body for which you want to specify the geopotential. This configuration is described here. Look in particular for geopotential_row and geopotential_column.
  3. @Agustin: You would notice differences if you were trying to replicate very accurately real-life missions: the old geopotential would exhibit drifts of hundreds of kilometers over a few months to a few years depending on the altitude. Things will get more interesting though when we extend this to the Moon, where the geopotential is very weird and affects orbit stability, or to Mars, where the position of Phobos and Deimos is currently bogus. More to come in future versions: stay tuned. @Someone2018: We started working on this in August. Making it correct was the first challenge, and then making it fast was even more interesting.
  4. Thanks for the nice videos @AloE, and thanks for reporting the problem with 1b. I believe that I understand what is happening: there is a stupid mistake whereby the configuration of the integrator used in the game differs from the one we used to do the transit-time variation optimization. For the transit at JD2457721.38747, the former produces an effective transit at 20:34:47 (pretty much what you observe), the latter an effective transit at 21:18:08 (pretty much the correct value). Note that this probably tells us that the integrator is not converged for 1b, presumably because the step size we used is too large. Darn, we'll need to rerun the optimization... Created #1999 to track this. Follow the music there.
  5. All working as intended. KSP is just a bit confused by our DLL because they are unmanaged and it tries to load them as if they were .Net assemblies.
  6. Thanks for taking the time to find the mod causing the problem. From reading its description it's clear that it alters the physics, apparently in ways that are incompatible with Principia. We'll get in touch with @ferram4 to understand more.
  7. @IncongruousGoat: This is a very bizarre bug, and not one that has been reported before. My gut feeling is that this is a nasty interaction with some other mod, but these problems are exceedingly difficult to debug. The thing that is especially strange is that Principia only translates parts, and never rotates them. So we could be guilty for the engine being off-centre, for instance, but it's harder to see how we would cause the antenna to rotate. If you can put your save on dropbox we'll take a look, but don't hold your breath, more likely than not we won't be able to pinpoint the cause.
  8. I suspect that you have a mod that simulates a 32-bit architecture by claiming that the pointers are 32 bits. Something like that was in use when KSP didn't really work on 64-bit machines.
  9. You need to have (1) a 64-bit processor (2) a 64-bit installation of Windows (3) a 64-bit installation of KSP. At least one of these prerequisites is missing (I suspect that you have a 32-bit installation of KSP).
  10. @Clockwork13: As mentioned in the FAQs, you need version 6.0-2 of libc++. You must have a rather ancient version to be missing shared_mutex (it was added in the 3.4/3.5 timeframe).
  11. @AloE: Yes, that's correct. That's mostly a round number (in JD) that's happens to fall shortly before the first observation of TRAPPIST-1. We run a fairly complex and expensive optimization to determine orbital elements that match the observed transits, so it's convenient to start a short time before the first observation. Also, many sources give dates like "7282.80570" where the leading JD245 is omitted.
  12. @flyby2412: Cramer, the last version of Principia to support 1.2.2, can be obtained at No support, no bug fixes, no questions answered. This being said, we recommend to use RP-1 with 1.3.1 and the latest Principia. Other people seem to have been successful with that setup.
  13. @AloE: Regarding EVE and Scatterer: please see my response on the Principia thread. You want to download trappist-1 for principia δημόκριτος.zip which should do what you want.
  14. Ah, thanks a lot for reporting this, @AloE. It turns out that while we coordinated with @GregroxMun when he was developing version 0.6.0 of his SLIPPIST-1 mod, we never fixed the link if the FAQs. So the version that you downloaded (trappist-1 for principia was designed for 0.5.x and had plenty of problems, one of which was an incompatibility with Kopernicus that caused the crash that you encountered. I have fixed the link in the FAQs to point to trappist-1 for principia δημόκριτος.zip. I suggest that you download this version and install it instead of what you have at the moment. It is better in a number of ways, in particular better alignment of the planetary textures, more realistic radius and atmospheres, data suitable for EVE and Scatterer, etc. (See PR #1856 and #1859 for details.) Apologies for the confusion caused by the outdated FAQs.