Axial tilt

[Teilnehmer]

Now, every celestial body of the Kerbol system has zero axial tilt.

How about tilting some planets?

I’d like to see a Uranus-like planet turning on its side, a Venus-like planet turning backwards, Earth-like planets with a moderate axial tilt.

Edited December 8, 2015 by Teilnehmer

[Hannu2]

That would be great. Unoftrunately, it has been suggested millions of times but Squad has declined to do it. In my opinion it is the worst and most annoying deficiency in this game. It is so essential thing in real space activities and it would be very easy to implement in software. Even if  it is not suitable to numberless celestial mechanics of Squad they could allow mods to do it.

 

[Tex_NL]

It's not that SQUAD doesn't want axial tilt. It's because the game engine doesn't allow it.
If it was possible some planets would be definitely tilted. Either stock or through mods.

[Hannu2]

I do not believe that Unity does not allow axial tilt of simple spherical object. All 3D engines can rotate objects around arbitrary axes. If it can be done with spacecrafts it can also be done with planets. It is just coordinate transformations, simple mathematical tricks which is already used in KSP.

Even Squad have never blamed Unity to every problem. Many things players think are Unity's restrictions are intended choices. Squad have done huge work to make basic spaceflight possible without all mathematical data but still keeping some sense of reality. I am sure that it is economically very good decision, but unfortunately they have loved little too much in their oversimple philosophy. They should at least allow mods to do axial tilts as they have done with data displays (MechJeb, KER) or aerodynamics (FAR).

[jwbrase]

18 minutes ago, Hannu2 said:

I do not believe that Unity does not allow axial tilt of simple spherical object. All 3D engines can rotate objects around arbitrary axes. If it can be done with spacecrafts it can also be done with planets. It is just coordinate transformations, simple mathematical tricks which is already used in KSP.

As I understand it, it's not a matter of not being able to rotate the planet object itself around an arbitrary axis (ships, after all, can rotate arbitrarily), but a matter of the physics calculations in an object's SOI being simpler if the rotational axis is aligned with one of the coordinate axes, and Unity not being able to have differently rotated coordinate systems in different SOIs.

[Hannu2]

I do not see reason for such problems. There is in any case one coordinate transformation at SOI transition. It is practically a matrix product, rotation includes only few terms in transformation matrix. If there is not complete tool in Unity it is easy to program by hand. If needed, planets outside of SOI can be transformed to new coordinates for drawing. It is just couple of matrix products. Interacions between objects through SOI boundaries could be somewhat more difficult to handle but there are no such interactions in KSP.

[Pthigrivi]

Yeah I had heard about the unity issue before, anyone know if unity 5 changes this?

[Red Iron Crown]

It's not a Unity thing afaik, but inertia with the existing code. Almost all of KSP's calculations and modelling are built with the assumption of zero axial tilt, to add support for it would require close to an entire rewrite of everything orbit-related.

It's really too bad, it would be a great feature IMO.

[NathanKell]

1. It's false that all bodies have 0 tilt. Each body has a tilt in degrees precisely equal to its inclination in degrees, because each body's polar axis is locked to world up/down no matter the inclination.

2. As RIC says it's not a Unity limitation at all, just a "wait, how much code do I have to rewrite!?" limitation.

[NemesisWolfe]

On 08/12/2015 at 7:27 PM, NathanKell said:

1. It's false that all bodies have 0 tilt. Each body has a tilt in degrees precisely equal to its inclination in degrees, because each body's polar axis is locked to world up/down no matter the inclination.

2. As RIC says it's not a Unity limitation at all, just a "wait, how much code do I have to rewrite!?" limitation.

Just wondering if this is something that is planned somewhere in the future.
Its the one thing I miss most in the kerbal universe, everything else can be solved with mods.

Edited June 15, 2016 by NemesisWolfe