What is a skybox? The idea behind a skybox is that a carefully constructed texture, if mapped onto a cube appears like the sky and horizon from inside of the cube. A picture is the best way to explain so check out our website, http://www.ensight.com/skyboxes-5.html. In the animation, you can see the skybox from both outside of the textured cube and from inside of the cube. When you place geometry inside of the cube, it appears to be inside of an environment.