Dagger

[1.5.X] Tilt'Em (Planetary axial tilt) [v1.0.0] [25 Oct 2018]

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23 minutes ago, Arrowstar said:

So alright, question: are orbits around local bodies, like Kerbin, computed w.r.t. the body's new rotation axis and equatorial plane?  For example, if I tilt Kerbin and then launch due east from the equator, I will be in an equatorial orbit.  Is the inclination of that orbit with your mod 0 degrees (because it's measured against Kerbin's new equator) or something else (because it's measured against the universal coordinate system)?

Currently orbital elements are in reference to the ecliptic (universal coordinate system).  A due east launch from KSC will put you in orbit around Kerbin's equator, but the KER readout will say the inclination is ~23.4 degrees (Kerbin's axial tilt per this mod's cfg).  Having a readout that gives orbital data in reference to the equator is something that I think is needed.  I suspect it will likely require an upgrade to KER (and MechJeb, and whatever else uses or provides such information).

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Quick question, Is there anything this mod needs as a dependency? I see none listed, but when I download and merge the files into the game directory, it doesn't seem to work. I haven't played around with it too much yet, I've had very limited time to troubleshoot, so it may just be that I've done something stupid that will be simple to correct, but thus far I'm not seeing any errors in the install file structure....

It was, in fact, something stupid. The mod was working just fine. I just had to take a better look at it. :blush:

Edited by vardicd

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9 hours ago, OhioBob said:

The line of nodes of the equator randomly changes from one game launch to the next.  For instance, put a satellite in an equatorial orbit (you'll have to figure out the LAN by trial and error).  Shut the game down and restart.  The planet's axis will now be pointed in a different direction and the satellite will no longer be orbiting around the equator.  I did it three times.  First time the LAN was 84.54 degrees, second time it was 198.33, and the third time it was 266.13.

That answers my previous question :)

I was suspicious that tilt angle only is not enough to describe a rotation properly, and an additional azimuthal and a reference vector are required.

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So regarding the navball I've been doing some tests with the (still unreleased) 1.1 version (you can compile it tough) and it looks right as the "north" is pointing to the true north of the planet

This is how a plane going north just after takeoff looks in default KSP without the mod and with the mod:

Be9UsmS.png

Ignoring the camera rotation, both planes are going to the "north" and you can check it in the commnet line that the heading is correct.

Same applies when going east (ignore the camera rotation):

0zbTZMO.png

 

I'm aware of the planet rotation bug, from what I see I should somehow apply a rotation based on the epoch or some other orbital parameter so it's consistent across saves... I'm working on that ;)

 

PS: Another test I did. In this case Kerbin has a tilt of 45º and the plane is going east, I extended the ecliptic line and the angle is correct

juWNkfj.png

Edited by Dagger

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Thank you. I knew this was possible but lacked the skills to do it, patience to learn, and jerkiness to demand it of others.

I'm starting a new career for the first time in a long time, because of you.

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Just now, 5thHorseman said:

Thank you. I knew this was possible but lacked the skills to do it, patience to learn, and jerkiness to demand it of others.

I'm starting a new career for the first time in a long time, because of you.

There are still bugs as the tilts are not consistent across times so have that in mind ;) 

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15 minutes ago, Dagger said:

There are still bugs as the tilts are not consistent across times so have that in mind ;) 

Oh I'm used to bugs I play ksp after all :D

And I probably won't start right away. Gotta play with the values a lot to find interesting setups.

Edited by 5thHorseman

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@Dagger

may I suggest that PlanetTilt.cfg uses planet names instead of index numbers, that would make it significantly easier to modify and robust for any changes in star system composition.

Edited by FreeThinker

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30 minutes ago, FreeThinker said:

@Dagger

may I suggest that PlanetTilt.cfg uses planet names instead of index numbers, that would make it significantly easier to modify and robust for any changes in star system composition.

Next version cfg file will be much better. You can see it here:

https://github.com/LunaMultiplayer/TiltEm/blob/master/TiltEm/PlanetTilt.cfg

I'm still not satisfied with the "TILTX" and "TILTZ" names... There must be some more technical name...

Edited by Dagger

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4 minutes ago, Dagger said:

 

Next version cfg file will be much better. You can see it here:

https://github.com/LunaMultiplayer/TiltEm/blob/master/TiltEm/PlanetTilt.cfg

I'm still not satisfied with the "TILTX" and "TILTZ" names... There must be some more technical name...

Better than what I'd have used (TiltSideways and TiltUpAndDown)

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8 minutes ago, Dagger said:

I'm still not satisfied with the "TILTX" and "TILTZ" names... There must be some more technical name...

 

What is important is that its clear what effect they have, which certainly is the case

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49 minutes ago, ZingidyZongxxx said:

This is amazing, do you know if it is compatible with old saves or will that break everything?

The only thing that could happen is that geostationary orbits get "broken" as they won't be above the same part of the planet where you left them

Edited by Dagger

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1 hour ago, Dagger said:

The only thing that could happen is that geostationary orbits get "broken" as they won't be above the same part of the planet where you left them

Awesome, thank you!

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Just now, KSPFanatic102 said:

Does this mod work with 1.4.5

Not tested but it should

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6 hours ago, Dagger said:

So regarding the navball I've been doing some tests with the (still unreleased) 1.1 version (you can compile it tough) and it looks right as the "north" is pointing to the true north of the planet

Yes, I did some testing as well and I too think the NavBall is correct.  I placed a satellite into a equatorial orbit and pointed it at +Normal.  The Level and +Normal indicators on the NavBall remained positioned exactly on the intersection of the horizon and the N line throughout an entire orbit.  This tells me that the satellite's longitudinal axis is continuously pointing at true north.  This is what we should see if the NavBall were correctly identifying the new north pole.  When I put the satellite in non-inclined orbit (relative to the ecliptic), the Level and +Normal indicators would oscillate around north, pointing true north only two times per orbit.  This is again what I would expect if the NavBall were working correctly.
 

Edited by OhioBob

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4 hours ago, Dagger said:

 

Next version cfg file will be much better. You can see it here:

https://github.com/LunaMultiplayer/TiltEm/blob/master/TiltEm/PlanetTilt.cfg

I'm still not satisfied with the "TILTX" and "TILTZ" names... There must be some more technical name...

With this new config file structure, how do modded planets work? If the name of the new planet is written in as a new entry, does the mod recognize it and apply the tilt accordingly?

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34 minutes ago, VonFrank said:

With this new config file structure, how do modded planets work? If the name of the new planet is written in as a new entry, does the mod recognize it and apply the tilt accordingly?

A Kopernicus patch is on the way, but yes, you use the modded planet names by replacing the default KSP ones and add more if you need

59 minutes ago, OhioBob said:

Yes, I did some testing as well and I too think the NavBall is correct.  I placed a satellite into a equatorial orbit and pointed it at +Normal.  The Level and +Normal indicators on the NavBall remained positioned exactly on the intersection of the horizon and the N line throughout an entire orbit.  This tells me that the satellite's longitudinal axis is continuously pointing at true north.  This is what we should see if the NavBall were correctly identifying the new north pole.  When I put the satellite in non-inclined orbit (relative to the ecliptic), the Level and +Normal indicators would oscillate around north, pointing true north only two times per orbit.  This is again what I would expect if the NavBall were working correctly.
 

Regarding the bug you posted on github I think it's fixed on 1.1. You can get the build from the "artifacts" in the appveyor:

https://ci.appveyor.com/project/gavazquez/tiltem

Edited by Dagger

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What a fantastic mod !
Is it compatible 1.4.5 and with Principia ? I can't wait to add this mod to my game !

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Dear Mr. @Dagger

I have something to report, NavBall, using the mod is misaligned a few degrees, I know the planet needs an angulation and that favors in several situations however with Naval misaligned it is strange to pilot in Kerbin and confuses me enough when I am flying by instruments.

However your mod mod is incredible, what is missing now would be the tidal effect. =) 

Thank you for making planetary tilt possible.

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Kerbin now has seasons. :)

Has anyone tried to look if Kerbol dances in the Moho's sky like the Sun dances in Mercury's?

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1 hour ago, Catatau_27 said:

Dear Mr. @Dagger

I have something to report, NavBall, using the mod is misaligned a few degrees, I know the planet needs an angulation and that favors in several situations however with Naval misaligned it is strange to pilot in Kerbin and confuses me enough when I am flying by instruments.

However your mod mod is incredible, what is missing now would be the tidal effect. =) 

Thank you for making planetary tilt possible.

Just check some posts above yours, I've done several navball tests and it works fine on the 1.1 (you can get it compiling the code or in appveyor) not sure if on 1.0 is buggy

Edited by Dagger

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9 hours ago, Dagger said:

I'm still not satisfied with the "TILTX" and "TILTZ" names... There must be some more technical name...

axialTiltX and axialTiltZ... Axial Tilt is the technical name for this so that would make sense for identifiers.

EDIT: ObliquityX and ObliquityZ would also make sense but I expect Axial Tilt is more recognisable.

Edited by Poodmund

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