pro Thoughts: intuitive interaction

James Burrows, technical director at award-winning creative production studio Immersive Studios, discusses how to effectively implement interactivity into a seamless VR experience

How to effectively implement interactivity into virtual reality

The whole point of virtual reality (VR) experiences is to suspend disbelief sufficiently to make you feel as if you’ve stepped into a whole new world. Being able to interact with that world makes it all the more convincing. However, interaction can make or break the illusion. The ultimate ambition for VR experiences is for there to be a way of interacting that’s so seamless it feels completely natural. ‘Natural Interfaces’ are the VR developer’s dream and have no need for external controllers. We’re not quite there yet, but the following methods are common ways we can add interactivity to VR.

Hand controllers

The most prevalent interactivity systems for VR, these range from simple point-andclick mechanisms for headsets such as the Gear VR or Daydream, to more complicated dual-hand controllers such as those for the HTC VIVE or the Oculus Rift. These offer multiple functionality, ranging from triggers to trackpads, reflecting a variety of options in the experience or game.

Gaze detection

This was one of the main ways to activate elements of a VR experience when mobile headsets started gaining in popularity, and today it still has its uses – e.g. at busy trade shows or events where there’s every chance a hand controller will go missing! In fact, a lot of developers implement gaze direction as a fallback even if they feel the user will more likely use a hand controller.

Hand tracking

This method involves a third-party piece of software, such as a Leap Motion or glove controllers, and enables people to see and use their hands in the virtual world. The concept is sound but so far the technology has yet to live up to the VR developer’s dream, as it can be inaccurate. A lot of developers are waiting for this type of tech to be built directly into the headset, which is on the cards for later in 2019.

choosing your interactivity

There are a few key points you need to consider before you implement an interaction system in your experience: • Your hardware – this will straightaway determine your options. If your experience is only going to be available on an Oculus Go, then you only need to worry about the point-and-click controller. The VIVE, Rift or Playstation, on the other hand, offer more detailed functionality. • The type of experience – are you building a game, a simulation or a brand experience? Games and simulations tend to require more functionality so you should consider more than just point-and-click or hand tracking. A brand experience will more likely be used at a trade show or event, meaning something simple like gaze detection is more suitable. • The competency of the end user – this is very important. If the end user has never tried VR before, then you need to implement a simple interactivity system. Struggling with a controller you can’t see is never going to be a good user experience and may put people off VR. If, on the other hand, you’re aiming at gamers or a tech-savvy audience, you can reasonably assume they’ll be able to find their way around a controller quickly.

intuition is key

What is the most intuitive way to interact with the experience? Does it feel more natural to point and click or to use a trigger, or simply to look? How you interact will always depend on hardware, but just because you have access to a VIVE doesn’t mean you need to find a function for every button on the controller. Instead, ask yourself how big a learning curve your user will have – are they a novice or are they a dedicated gamer? By putting yourself in your user’s shoes, you’ll be able to choose an interaction system that makes the most sense and keeps the virtual illusion going.