A Survey of Characteristic Engine Features for Technology-Sustained Pervasive Games

Virtual world, defined from a technological perspective and applied to video games, mixed reality, and the Metaverse

“…It should be noted that there are several abstractions of simulation possible within a computing device, for example, (in general) the micro instructions of the CPU simulate instructions of the CPU, which in turn simulate assembly or higher level languages, which in turn simulate the operating system of a computer, and which in turn can simulate the software engine simulating a VE. If a technology can provide for one or more ( MANY ) “data spaces,” then the loaded state in MANY data spaces can possibly constitute a VE. It is possible to have MANY environments nested in other environments (e.g., multiple software running on the OS); a virtual world is a specialization of MANY VEs.…”

“…Software running in a computer (e.g., a virtual world engine) will run according to ST but can simulate another abstraction of time, called VT, for its loaded state (e.g., a VE). VT can be simulated by establishing an epoch for VT (e.g., zero or ST when the state was loaded) plus an offset.…”

“…Bartle's criterion that the world must “continue to exist” can be referred to as “world persistence” (wP), that is, the world continues to exist and is available to the players when they want to access it. To ensure world data is not lost in the event of system failure, the system must support “data persistence” (dP) for all data spaces that hold nonephemeral data. It is precisely VT that allows for a loaded state to be persisted to storage and reloaded without side effects; without the abstraction of time, that world's time would freeze during storage, suddenly rewind on a rollback or fast forward to the current real‐world time on load.…”

“…The problem with persistence is that it can be simulated, without raising awareness to the player, for example, if a world is made available to players at all times, they want to access it; it is seemingly always in existence. A straightforward way to achieve this is to have scheduled play times around down times . The simulation of P can be generalized as pseudo‐persistence .…”

“…Singhal and Zyda state that the place in a shared sense of space, may be real or fictional. It is assumed that this statement is mentioned to include the physical aspect of a video conference but not meant to include “pervasive systems.” If the latter is the case, there is not enough clarification provided in the rest of the definition to handle pervasiveness (see Mixed Reality), for example, a virtual persona projected into the physical world would seem to be included in definition, but a human interacting with that projection in the physical shared space fails the avatar requirement by Singhal and Zyda. A shared sense of time by Singhal and Zyda implies real‐time interaction, but in Definition , it is made explicit.…”