code: public Quaternionf add(float x, float y, float z, float w) {
          return new Quaternionf(this.x + x, this.y + y, this.z + z, this.w + w);
      }
docs: Adds the float components of another quaternion to this one.
  
  @param x The x (imaginary) component of the quaternion to add
  @param y The y (imaginary) component of the quaternion to add
  @param z The z (imaginary) component of the quaternion to add
  @param w The w (real) component of the quaternion to add
  @return A new quaternion, which is the sum of both