from_rotation_vector

quaternion_core

Function from_rotation_vector 

Source 
pub fn from_rotation_vector<T>(r: Vector3<T>) -> Quaternion<T>
where
    T: Float + FloatConst,
Expand description

Converts a Rotation Vector into a Versor.

A Rotation Vector is a convenient representation where:

  1. Its direction defines the rotation axis.
  2. Its norm defines the rotation angle (in radians).

There are no particular restrictions on the norm of the input Rotation Vector. Also, even if a zero vector is input, the conversion to a Versor can be performed without falling into a singularity.

ยงExamples

let angle = PI / 2.0;
let axis = [1.0, 0.0, 0.0];
 
// This represents a rotation of pi/2 around the x-axis.
let rot_vec = scale(angle, axis);  // Rotation vector
 
// Rotation vector ---> Quaternion
let q = from_rotation_vector(rot_vec);
 
let r = point_rotation(q, [1.0, 1.0, 0.0]);
 
assert!( (r[0] - 1.0).abs() < 1e-12 );
assert!( (r[1] - 0.0).abs() < 1e-12 );
assert!( (r[2] - 1.0).abs() < 1e-12 );