Sky entities are either dome, cylinder, or cube mapped, depending on flags given in the definition. When no such flag is set, the sky entity is rendered into the level background at its x y z position given. This way, sun, moon or other celestial objects can be drawn onto the sky. LC In lite-C, sky entities are defined the same way as view entities, except that their SKY flag is set.
When you are using several sky layers, take care to disable any layer that is not visible, and also disable the background color (sky_color). This avoids unnecessary rendering and keeps the frame rate high.
ENTITY* skycube = { type = "skycube+6.tga"; // the image for a backdrop scene flags2 = SKY | CUBE | SHOW; // sky cube, visible }
SKY skycube = { type = "skycube+6.tga"; // the image for a backdrop scene flags = CUBE | SHOW; // sky cube, visible }