def correct_uv(uv, vector, azimuth)
      return Vector2.new(uv.x - 1.0, uv.y) if azimuth < 0
      return Vector2.new(azimuth / 2.0 / Math::PI + 0.5, uv.y) if vector.x.zero? && vector.z.zero?
      uv.clone
    end
def correct_uv(uv, vector, azimuth)
      return Vector2.new(uv.x - 1.0, uv.y) if azimuth < 0
      return Vector2.new(azimuth / 2.0 / Math::PI + 0.5, uv.y) if vector.x.zero? && vector.z.zero?
      uv.clone
    end
Texture fixing helper. Spheres have some odd behaviours.