Virtual Worlds

 

"Virtual" used to mean something like "exactly" but now it means something like this.

Essential Meaning of virtual

1

: very close to being something without actually being it

The country is ruled by a virtual dictator. [=by someone who is not officially a dictator but who is like a dictator in every important way]

Her victory is a virtual certainty. [=she almost certainly will win]

The species is nearing virtual extinction. [=it is almost extinct]

2

: existing or occurring on computers or on the Internet

a virtual library

virtual shopping

Creeping into the science of computer systems, "virtual" became a powerful concept as early as the late 1960s. Programs were assigned "virtual memory" that "looked" like real memory but could be moved around or swapped out to disk according to the needs of the operating system. The idea grew from there, underpinning the architecture of "mainframe" computers and when I last worked for a living, I worked on "virtual" PCs - PCs simulated on other PCs. As a result, I have found the whole idea of "virtualization" quite natural for almost 50 years.

The Matrix is populated by "virtual" people - the "real" ones asleep in pods (sorry, spoiler). This idea caught on almost seriously for many who wondered if reality itself is a "virtual world". You are free to play around with this concept. I don't take it seriously.

In both Second Life and Oculus VR, we are presented with virtual worlds. In both cases (and similar technologies), the "world" is created internally as a structure that can be viewed by what can be thought of as a separate "app" altogether. In a PC or Mac, the "work" of presenting a 3D structure on a 2D surface (or 2 surfaces in the case of VR goggles) is greatly assisted by modern graphics cards - perhaps the most powerful but unappreciated component of the modern computer.

If your "world" is to be shared by multiple virtual people (avatars), there needs to be a central store of shared information - a "server" - that tracks and shares all the relevant goings-on in the shared virtual environment. This, in turn, means that relatively fast communication needs to exist between the personal "world" (in headset or computer) and the shared model. This is never perfect and it results in the bane of all virtual worlds: lag. This means that not all users are experiencing exactly the same, consistent world.

I am tempted to provide some diagrams here. Trust me, such diagrams would make things even more confusing. I am working on a picture for you, but this is what the picture should show (skip this if you like):

• The vendor provides one or more services in the cloud, including a "world", like Second Life;
• These services run on a server "farm" - mostly on Amazon Web Services;
• The "world" is broken into many different "rooms", each simulating a shared experience, each running on its own processor thread. In some cases, a single physical CPU may host multiple threads.
• At the client end, a model software communicates with the server "room" and builds a model room out of the data provided by the server
• A viewer provides a user interface that "shows" the model 
• The user's brain experiences the model through the interface as more or less "immersive"..

In multiplayer games, all this can be simplified by making the avatars "multiple choice" rather than custom and making the game space fixed. The result can be very lively action with relatively low bandwidth and a relatively low-power personal computer.

At the client end, the "room" can be quite large but fixed - the same room for all players. For example, a World of Warcraft room may require many gigabytes of client hardware. This requirement rules out stand-alone wireless headsets such as the Oculus Quest - at least for the moment.

Old "virtual" tricks can be used to load world data "on-demand". For example, settings in Second Life allow you only to see things close to you or to omit detail (such as shadows). All this needs to be updated "on the fly", resulting in the ban of all Virtual Reality applications: lag. Even worse, lag may result in multiple players in the same room seeing different things.

All this falls far short of the ideal "virtual" experience, such as the holodeck on the Star Ship Enterprise.

• Visual input can be one or two 2D screens. 3D screens (goggles) can produce the illusion of depth but the architecture of the system is not fundamentally different;
• Auditory input, including sound effects and talk between characters, is a much-valued feature;
• Haptic input, such as a little bump on the paddles, makes a huge difference.

I pick up this thread with consideration of Hawkins' "Thousand Brains" hypothesis and how it provides a useful definition of "felt reality". What does it take to make a "Virtual" world feel real?

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