In this course, we're talking about how users and players can interact with our virtual reality world. In some ways, this is just like interacting with a piece of software, like an app or a game. When we talked about graphics and virtual reality, we said that VR graphics are not so different from other 3D graphics. What about interaction? Well, when it comes to interaction, VR really is different. I'ts a total paradigm shift in terms of how we interact with software. Why is that? Well, the reasons that are quite basic and straightforward. Reasons why things that work on a phone or a laptop when working VR. One of the most basic points is that you have a head mounting display covering your eyes. That means you can actually see the interaction devices that you have in front of you. It's pretty hard to type on a keyboard if you can't see the keys. That means a lot of the interfaces like mouse and keyboard don't work in VR because you can't really use them. Another reason is that a lot of interfaces are designed for 2D. If you think of a web page it's designed to 2D playing with content on it. A mouse and a touch screen are both fundamentally designed for 2D interaction. They allow you to move around on the surface and select things, but they don't allow you to interact with depth. Virtual reality on the other hand is fundamentally 3D. You're interacting all around you in a 3D space. A mouse just won't work. So we definitely need new types of interaction devices to make me VR usable at all, but there are other deeper psychological reasons why virtual reality interaction is different. Virtual reality is about transporting you to a virtual world. So the job of virtual reality interaction isn't just to make our environment easy to use, It is about making us feel we're inside that virtual world. Virtual reality is all about creating the three illusions that make up presence. Place illusion, the feeling that we're in a different world. Plausibility illusion, the feeling that the world is real and that is responding to us. And embodiment illusion, the feeling that we have a body in the virtual world. Place illusion is about your movement and your perceptions matching. It's mostly handled by the fundamental interactions of virtual reality, like when your head moves, and your view, the direction you're looking in changes. These are built into any virtual reality headset, and so pretty much come for free. Embodiment is about linking your body to the interaction. Feeling that you are interacting with your body, rather than a mouse or game controller. It comes from having a visual representation of your body, or at least your arms as you interact, but it also comes from really moving as we interact, not just pressing buttons. You will feel more embodied if you actually reach out to pick something up with your hands, rather than just pressing a button. Plausibility is probably the most important illusion when it comes to interaction. It is about the world responding to you in a way that's credible. What credible means is that things respond to you as they would in the real world. So it's really important that the VR world responds to you when you try to interact with it. But in a sense, that isn't anything new, most games or apps do respond to you. That's point of interaction. But a lot of these don't respond in the same way the real world does. Sure, you can have metaphors, computer interfaces are based on the metaphor of a desktop. That means the way they're laid out is a bit like a traditional desk. That metaphor helps us understand and remember what we are supposed to do. But it's just a metaphor. A computer desktop is not like a real desk. It doesn't have pens and paper on it. You can't pick things up and put them down. For you to feel like you have a desk in front of you in virtual reality, it shouldn't just interact like a metaphorical desk, it should interact like a real desk. Only if it works like a real desk will it actually feel like you're transported to a new virtual space. So, when you are developing for VR, your first thought shouldn't be about how you would interact with games or apps. You should really think about how you interact with the real world.
