In this chapter we learned how to add a skybox by using a cube and cube mapping to apply a skybox texture onto the cube. We also learned about index arrays and how they can help reduce memory usage when an object has a lot of shared vertices.
While we used cube maps in this chapter for the skybox, they can be used for other things too. A cube map can also be used as an environment map on an object to make it appear reflective or shiny. Index arrays will also come quite in handy when dealing with more complex objects and scenes, though it is always best to benchmark and compare the choices and then use the one that performs the best.