subtract = (out, a, b) => {
  out[0] = a[0] - b[0]
  out[1] = a[1] - b[1]
  out[2] = a[2] - b[2]
  return out
}
Subtracts the coordinates of two vectors (A-B).

@param {vec3} out - receiving vector
@param {vec3} a - minuend vector
@param {vec3} b - subtrahend vector
@returns {vec3} out
@alias module:modeling/maths/vec3.subtract