Quaternion. A 4-dimensional vector representing a rotation. The vector represents a 4 dimensional complex number where multiplication of the basis elements is not commutative (multiplying i with j gives a different result than multiplying j with i). Multiplying quaternions reproduces rotation sequences. However quaternions need to be often renormalized, or else they suffer from precision issues. It can be used to perform SLERP (spherical-linear interpolation) between two rotations. http://docs.godotengine.org/en/latest/tutorials/3d/using_transforms.html#interpolating-with-quaternions Returns a quaternion defined by these values. Returns a quaternion that will rotate around the given axis by the specified angle. The axis must be a normalized vector. Returns the rotation matrix corresponding to the given quaternion. Performs a cubic spherical-linear interpolation with another quaternion. Returns the dot product of two quaternions. Returns the inverse of the quaternion. Returns whether the quaternion is normalized or not. Returns the length of the quaternion. Returns the length of the quaternion, squared. Returns a copy of the quaternion, normalized to unit length. Performs a spherical-linear interpolation with another quaternion. Performs a spherical-linear interpolation with another quaterion without checking if the rotation path is not bigger than 90°. Transforms the vector [code]v[/code] by this quaternion. W component of the quaternion. Default value: [code]1[/code] X component of the quaternion. Default value: [code]0[/code] Y component of the quaternion. Default value: [code]0[/code] Z component of the quaternion. Default value: [code]0[/code]