Diegesis is a style of fiction storytelling in which a participating narrator offers an on-site, often interior, view of the scene to the reader, viewer, or listener by subjectively describing the act
In the game Dead Space, the colored spine of the player's spacesuit is used to indicate the health points of their character. This is rendered within the environment of the game, as part of the player's character. Ammo, mission updates, and several key menus are also rendered in the game world, which are viewed by the player's character.