void Quaternion::from_axis_angle(Vector3f v) {
float theta = v.length();
if(theta < 1.0e-12f) {
q1 = 1.0f;
q2=q3=q4=0.0f;
return;
}
v /= theta;
from_axis_angle(v,theta);
}
/**
* Rotation quaternion from vector
*
* The axis of rotation is given by vector direction and
* the angle is given by the norm.
*
* @param vec rotation vector
* @return quaternion representing the rotation
*/
void from_axis_angle(Vector<Type, 3> vec) {
Quaternion &q = *this;
Type theta = vec.norm();
if(theta < (Type)1e-10) {
q(0) = (Type)1.0;
q(1)=q(2)=q(3)=0;
return;
}
vec /= theta;
from_axis_angle(vec,theta);
}
