void node_displacement_object(float height, float midlevel, float scale, vec3 N, out vec3 result)
{
  N = transform_direction(ModelMatrix, N);
  result = (height - midlevel) * scale * normalize(N);
  /* Apply object scale and orientation. */
  result = transform_direction(ModelMatrix, result);
}

void node_displacement_world(float height, float midlevel, float scale, vec3 N, out vec3 result)
{
  result = (height - midlevel) * scale * normalize(N);
}