KeplerTranslation

Inherits Translation

Members

Name	Documentation	Type	Description	Optional
ArgumentOfPeriapsis	This value determines the argument of periapsis in degrees, that is the position on the orbit that is closest to the orbiting body.	Double	In range: ( -360,360 )	No
AscendingNode	This value determines the right ascension of the ascending node in degrees, that is the location of position along the orbit where the inclined plane and the horizonal reference plane intersect.	Double	In range: ( -360,360 )	No
Eccentricity	This value determines the eccentricity, that is the deviation from a perfect sphere, for this orbit. Currently, hyperbolic orbits using Keplerian elements are not supported.	Double	In range: ( 0,1 )	No
Epoch	This value determines the epoch for which the initial location is defined in. This is specified either in the form of a date (YYYY MM DD HH:mm:ss) or in the number of seconds past the J2000 epoch.	String, or Double	Value of type ‘String’, or Value of type ‘Double’	No
Inclination	This value determines the degrees of inclination, or the angle of the orbital plane, relative to the reference plane, on which the object orbits around the central body.	Double	In range: ( -360,360 )	No
MeanAnomaly	This value determines the mean anomaly at the epoch in degrees, which determines the initial location of the object along the orbit at epoch.	Double	In range: ( -360,360 )	No
Period	Specifies the orbital period (in seconds).	Double	Greater than: 0	No
SemiMajorAxis	This value determines the semi-major axis, that is the distance of the object from the central body in kilometers (semi-major axis = average of periapsis and apoapsis).	Double	Value of type ‘Double’	No

Inherited members from Translation

Name	Documentation	Type	Description	Optional
Type	The type of translation that is described in this element. The available types of translations depend on the configuration of the application and can be written to disk on application startup into the FactoryDocumentation	String	Must name a valid Translation type	No
TimeFrame	The time frame in which this Translation is applied. If the in-game time is outside this range, no translation will be applied.	Table	TimeFrame	Yes

Asset Examples

-- Rotation Following One Moving Object
-- This asset creates a rotation that places coordinate axes orbiting close to a sphere
-- with the z axis always pointing towards the sphere as it orbits around the sphere. The
-- coordinate axes are translated away from the sphere to make that orientation more
-- obvious.
--
-- Making the `YAxis` { 0.0, 1.0, 0.0 } and actually using the orthogonal projection of
-- that direction means that the y axis of the new coordinate system will point in the
-- hemisphere in which the old y-axis was pointing, albeit being orthogonal to the other
-- specified axis. That axis is pointing towards the scene graph node holding the sphere.
local Sphere = {
  Identifier = "FixedRotation_Example_Moving_Sphere",
  Transform = {
    Translation = {
      Type = "KeplerTranslation",
      Eccentricity = 0.5,
      SemiMajorAxis = 0.0025,
      Inclination = 0.0,
      AscendingNode = 0.0,
      ArgumentOfPeriapsis = 0.0,
      MeanAnomaly = 0.0,
      Epoch = "2000 JAN 01 12:00:00",
      Period = 10.0
    }
  },
  Renderable = {
    Type = "RenderableSphericalGrid"
  },
  GUI = {
    Name = "FixedRotation - Moving (Sphere)",
    Path = "/Examples"
  }
}

local Node = {
  Identifier = "FixedRotation_Example_Moving",
  Transform = {
    Rotation = {
      Type = "FixedRotation",
      Attached = "FixedRotation_Example_Moving",
      YAxis = { 0.0, 1.0, 0.0 },
      YAxisOrthogonal = true,
      ZAxis = Sphere.Identifier
    }
  },
  Renderable = {
    Type = "RenderableCartesianAxes"
  },
  GUI = {
    Name = "FixedRotation - Moving",
    Path = "/Examples"
  }
}

asset.onInitialize(function()
  openspace.addSceneGraphNode(Sphere)
  openspace.addSceneGraphNode(Node)
end)

asset.onDeinitialize(function()
  openspace.removeSceneGraphNode(Node)
  openspace.removeSceneGraphNode(Sphere)
end)