US Patent 10486062 Information processing apparatus and warning presentation method

In a real space that includes a user, predetermined rules are used to set boundary surfaces of a play area in reference to boundary surfaces of the field of view of an imaging device. If the user gets out of the play area, a warning state determining section determines that there is a need for a warning and superposes a warning image on a display image. A direction in the real space or the state therein, for example, is used to determine whether or not margin areas are to be set between the boundary surfaces of the play area and the boundary surfaces of the field of view, or how wide the margin areas are to be.