What is a ‘Believable’ Virtual World?

Over the years we have played with a number of terms to describe what we’re trying to accomplish in our virtual reality content, and the word ‘believable’ has been a consistent part of it. We want to create worlds that feel like a believable reality. But that does not necessarily mean it has to be like our reality or that it needs to be realistic.

While a full and accurate simulation of our reality could be called the ultimate believable virtual world, it is still the case that a world doesn’t necessarily have to be realistic in order to feel believable to us. What it boils down to for VR content creators is whether we can create an illusion that feels believable to users, regardless of whether it tries to be like our reality or an alternate one. So what makes a reality feel believable, and what does it mean for a virtual world to be believable? Let’s explore some of the fundamentals!

What Do you Mean ‘Believable’?

Generally speaking, a user finds a virtual world believable when we meet his/her’s expectations of how a real world works. Whether that’s object interactivity, character reactions or something else, the more we meet these expectations the more convincing the illusion becomes. The virtual reality we are creating doesn’t necessarily have to be like our reality: visual photorealism or accurate emulation of our reality is not necessary to make a user believe, to some extent, that a world is real. This works because the mind is extremely powerful and adaptable. As long as certain conditions are met, humans are able to accept and ignore major differences and shortcomings between a make-believe world and the reality we all know.

Think about this: If our reality suddenly looked like a cartoon but nothing else changed, would we stop believing or feeling like it is real? What about if the laws of physics suddenly changed? Our sense of something feeling like reality derives from a complex combination of factors and how they engage our senses and our intellect. Some of those factors can be altered, omitted or stretched without our acceptance of it being reality completely breaking down.

Cartoons Can Feel Believable

Cartoons are a good foundation to talk about believability. Even though we know cartoons and cartoon characters are not ‘real’ or even remotely ‘realistic’, we still feel like they are. We accept the conditions of their reality and begin to form real emotions towards the characters and understanding of their worlds. We can even easily accept fantastical things like magic and feel awe towards their effects. We the users actually want and choose to believe the rules of made-up worlds from the start, including choosing to ignore certain unbelievable aspects of them. Our experiences Asunder and Waltz of the Wizard aspired to have visual similarities with our reality, for example, but they are not photorealistic and they don’t have to be. The characters in them react intelligently to physical user behavior, but not exactly like a real human being would nor as extensively. Yet that superficial resemblance to how living beings behave provides them with a degree of believability.

The Judges in Trial of the Rift Drifter and Waltz of the Wizard are not photorealistic, but they respond to physical movements intelligently like a real person would, providing them with a degree of believability.

On some level we are always aware that the movie on the screen is not real — or aware that a virtual reality is not reality — but we willingly try to ignore that fact. Content creators and VR users therefore always have an unspoken agreement that the world is not real and that the user will choose to believe it anyway, accepting the rules of how this new reality works and ignoring as much of its unbelievable aspects as possible. In the moment we can even become so immersed and present that we temporarily forget the reality we actually live in and fully accept the virtual world. (Believability, immersion and presence are all quite related — more on those connections in future posts!). How well the suspension of disbelief is then sustained depends on how well a content creator produces an illusion of a reality and fulfills the conditions required to help users accept and roleplay that this world is, in fact, a reality.

World Consistency is Key

Reality is governed by fundamental rules that logically constrain and control the number and nature of things that can happen. We as beings that evolved within that reality depend on such consistency to function properly, and our sense of something feeling believably real depends on a certain level of consistency and predictability being in place.

In order for a virtual world to feel believable, we need to meet the user’s expectations of how a reality works. This means believable virtual realities need to make sense to a certain degree and be consistent in the way that they work. As mentioned in the intro, these rules can be altered and do not necessarily need to fully reflect our own reality. But whatever the rules are they need to be clearly communicated to users so that they can start to understand and predict what can possibly take place in that reality. This consistency represents the framework through which we understand the things that take place in that world, building our expectations for what is possible. As users become familiar with a world they begin to form expectations about the world and what can happen, things start to “make sense“, which allows them to confidently understand (and more naturally exist within) that reality.

In Waltz of the Wizard we focused on believable world interactions, making almost everything consistently interactive or reactive to some degree. A butterfly was not just an animated loop, it responded to the users.

As long as a virtual reality consistently follows its rules, users will continue to make sense of it and able to comfortably suspend their disbelief, naturally existing within that world as if it were real. If something happens that seems out of place or inexplicable by the rules of that reality — if you can not make sense of it — then that’s something that potentially feels unbelievable. Your immersion is disrupted. It will make your mind go ‘wait… what!?’ and subsequently you will question the world itself and your own existence within it, serving as an annoying reminder that this is a make-believe reality. For a low level example; if a user is shown that objects in a virtual reality are interactive, but then it turns out that some objects are not interactive, then the user’s expectations will not be met and the illusion of a reality is broken (and it’s #%$!& disappointing). He/she is reminded that this is not a real world. However if the difference between interactive objects and non-interactive is visually communicated from the start, then the user is at least given the choice to accept and ignore this flaw and can then expect objects that look a certain way to not be interactive. (Note, though, that too many artificial things like object highlights, without an elegant in-world explanation, are also reminders that the world isn’t real!).

Let’s Wrap This Up

The believability of a virtual reality derives from the complicated relationship between an actual simulation and the human mind’s acceptance of it. Give your world traits and constraints of a reality and communicate those rules clearly to help users form expectations of how your reality works, then consistently meet those expectations. Avoid inconsistency that leaves users constantly figuring out how things work because it breaks the illusion of a reality and disrupts the experience of simply being there, serving as a periodic reminder that this is an artificial world. Remember that you are helping and encouraging users to willingly suspend their disbelief. A huge part of what we do at Aldin is to encourage users to want to believe they are in a reality, and a great way to do that is to make the user experience fun and comfortable. Make the user experience as comfortable and engaging as possible as they play along with whatever role is intended for them. Then, wherever possible, try to support any efforts of the user to roleplay that the world is, in fact, real. A major part of that is making the world interactive and reactive to user behavior, which are subjects which we will cover in future posts.

There are more factors at play than what’s mentioned here and post like this falls woefully short of adequately covering a subject like believability, and even choosing the terms and wording is a challenge in itself. But we hope some of you find our musings of interest and we love to hear from you! Feedback is welcome — one of our goals with our blogposts is to open up for community feedback, so we can all work together to improve overall understanding of subjects related to VR!