sample_orientation_uniform

vector4  sample_orientation_uniform(vector u)

u

Three numbers between 0 and 1.

Returns a unit vector4, i.e. a vector4 of length 1, based on u. Given uniform random u vectors of three values in [0,1), the returned unit vectors will be uniform random and continuous with respect to u on the surface of the unit hypersphere. In other words, they will be uniform random orientation quaternions.