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vec3 flakeNoiseBumpTexture( in texture_coordinate_info uvw, in float scale, in float strength, in vec3 normal )
{
  vec3 tex = uvw.position / scale;
  vec3 grad = miNoise( tex ).xyz;

  // displace coordinate according to noise value
  tex += 2.0 * grad;

  // then use only integer coordinates, to make flakes transients harder and not wobbly
  grad = miNoise( round( tex ) ).xyz;

  vec3 n = normalize(vec3(strength * grad.x, strength * grad.y, 1.0));
  n = n.x*uvw.tangent_u + n.y*uvw.tangent_v + n.z*normal;
  return normalize(normal + n);
}