addTime method
Implementation
Quaternion addTime(Vector3 v, double t ){
double ax = v.x, ay = v.y, az = v.z;
double qw = w, qx = x, qy = y, qz = z;
t *= 0.5;
x += t * ( ax*qw + ay*qz - az*qy );
y += t * ( ay*qw + az*qx - ax*qz );
z += t * ( az*qw + ax*qy - ay*qx );
w += t * ( -ax*qx - ay*qy - az*qz );
normalize();
return this;
}