final case class Quaternion(x: Double = 0.0, y: Double = 0.0, z: Double = 0.0, w: Double = 0.0, unknownFields: UnknownFieldSet = ...) extends GeneratedMessage with Updatable[Quaternion] with Product with Serializable

A quaternion is defined as the quotient of two directed lines in a three-dimensional space or equivalently as the quotient of two Euclidean vectors (https://en.wikipedia.org/wiki/Quaternion).

Quaternions are often used in calculations involving three-dimensional rotations (https://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation), as they provide greater mathematical robustness by avoiding the gimbal lock problems that can be encountered when using Euler angles (https://en.wikipedia.org/wiki/Gimbal_lock).

Quaternions are generally represented in this form:

w + xi + yj + zk

where x, y, z, and w are real numbers, and i, j, and k are three imaginary numbers.

Our naming choice (x, y, z, w) comes from the desire to avoid confusion for those interested in the geometric properties of the quaternion in the 3D Cartesian space. Other texts often use alternative names or subscripts, such as (a, b, c, d), (1, i, j, k), or (0, 1, 2, 3), which are perhaps better suited for mathematical interpretations.

To avoid any confusion, as well as to maintain compatibility with a large number of software libraries, the quaternions represented using the protocol buffer below *must* follow the Hamilton convention, which defines ij = k (i.e. a right-handed algebra), and therefore:

i2 = j2 = k^2 = ijk = −1 ij = −ji = k jk = −kj = i ki = −ik = j

Please DO NOT use this to represent quaternions that follow the JPL convention, or any of the other quaternion flavors out there.

Definitions:

  • Quaternion norm (or magnitude): sqrt(x2 + y2 + z2 + w2).
  • Unit (or normalized) quaternion: a quaternion whose norm is 1.
  • Pure quaternion: a quaternion whose scalar component (w) is 0.
  • Rotation quaternion: a unit quaternion used to represent rotation.
  • Orientation quaternion: a unit quaternion used to represent orientation.

A quaternion can be normalized by dividing it by its norm. The resulting quaternion maintains the same direction, but has a norm of 1, i.e. it moves on the unit sphere. This is generally necessary for rotation and orientation quaternions, to avoid rounding errors: https://en.wikipedia.org/wiki/Rotation_formalisms_in_three_dimensions

Note that (x, y, z, w) and (-x, -y, -z, -w) represent the same rotation, but normalization would be even more useful, e.g. for comparison purposes, if it would produce a unique representation. It is thus recommended that w be kept positive, which can be achieved by changing all the signs when w is negative.

Next available tag: 5

x

The x component.

y

The y component.

z

The z component.

w

The scalar component.

Annotations
@SerialVersionUID()
Linear Supertypes
Product, Equals, Updatable[Quaternion], GeneratedMessage, Serializable, Serializable, AnyRef, Any
Ordering
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  2. By Inheritance
Inherited
  1. Quaternion
  2. Product
  3. Equals
  4. Updatable
  5. GeneratedMessage
  6. Serializable
  7. Serializable
  8. AnyRef
  9. Any
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Visibility
  1. Public
  2. All

Instance Constructors

  1. new Quaternion(x: Double = 0.0, y: Double = 0.0, z: Double = 0.0, w: Double = 0.0, unknownFields: UnknownFieldSet = ...)

    x

    The x component.

    y

    The y component.

    z

    The z component.

    w

    The scalar component.

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  5. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  6. def companion: Quaternion.type
    Definition Classes
    Quaternion → GeneratedMessage
  7. def discardUnknownFields: Quaternion
  8. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  9. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  10. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  11. def getField(__field: FieldDescriptor): PValue
    Definition Classes
    Quaternion → GeneratedMessage
  12. def getFieldByNumber(__fieldNumber: Int): Any
    Definition Classes
    Quaternion → GeneratedMessage
  13. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  14. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  15. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  16. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  17. def serializedSize: Int
    Definition Classes
    Quaternion → GeneratedMessage
  18. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  19. final def toByteArray: Array[Byte]
    Definition Classes
    GeneratedMessage
  20. final def toByteString: ByteString
    Definition Classes
    GeneratedMessage
  21. final def toPMessage: PMessage
    Definition Classes
    GeneratedMessage
  22. def toProtoString: String
    Definition Classes
    Quaternion → GeneratedMessage
  23. val unknownFields: UnknownFieldSet
  24. def update(ms: (Lens[Quaternion, Quaternion]) ⇒ Mutation[Quaternion]*): Quaternion
    Definition Classes
    Updatable
  25. val w: Double
  26. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  27. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  28. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  29. def withUnknownFields(__v: UnknownFieldSet): Quaternion
  30. def withW(__v: Double): Quaternion
  31. def withX(__v: Double): Quaternion
  32. def withY(__v: Double): Quaternion
  33. def withZ(__v: Double): Quaternion
  34. final def writeDelimitedTo(output: OutputStream): Unit
    Definition Classes
    GeneratedMessage
  35. def writeTo(_output__: CodedOutputStream): Unit
    Definition Classes
    Quaternion → GeneratedMessage
  36. final def writeTo(output: OutputStream): Unit
    Definition Classes
    GeneratedMessage
  37. val x: Double
  38. val y: Double
  39. val z: Double

Inherited from Product

Inherited from Equals

Inherited from Updatable[Quaternion]

Inherited from GeneratedMessage

Inherited from Serializable

Inherited from Serializable

Inherited from AnyRef

Inherited from Any

Ungrouped