VUE is a virtual reality simulation app designed to be usable on devices both old and new, and even those without VR capabilities. By creating a unified experience across devices NYU students can concentrate on the learning materials, instead of an overly complicated application. Creating a user experience that can function fluidly on both Google Daydream and Google Cardboard is one of the first design and development challenges to overcome.
Pertinent differences between the two platforms
Cardboard uses a single button that clicks wherever the reticle is positioned in the user’s field-of-view. It also functions with no click input mechanism, using a fuse-timer. A fuse timer will automatically click after hovering over a target for a predetermined time, effectively allow a user to interact by gazing. Additionally, the Cardboard reticle is locked to the center of the user POV, and they must move their head to position it over interactive objects.
Daydream has multiple inputs through the use of a motion tracked controller with a touchpad and multiple buttons. It uses the motion tracked controller to point at targets in the manner of a laser-pointer, allowing more intuitive interaction and the separation of user gaze from an user input.
UX Design Challenges
Imagine a scenario where a user would like to select an object, move it to another point in space, and then drop it. On a PC this is easily done with a mouse by clicking and dragging. Using the Daydream mobile VR controller the act is very similar. You point, click to pick up, then use the controller to move the object and set it down. To produce the same functionality in Cardboard requires more creative solutions. A fuse timer must hover over an object for x seconds to click it. Once you grab an object, it is fixed to the reticle, which is in the center of the screen. That means you are still hovering over it, which could trigger the fuse to drop it again. Moving the object towards and away from yourself is also a challenge as there are no additional buttons or inputs. Our solution was to hover over a “Grab” button associated with the object. Once the object is grabbed, the fuse is locked until the user holds their head still for a set period. This way they can position the object how they like, then hold to unlock the fuse, which will then fire to drop the object. Tilting of the head left or right will bring the object closer or further away.
Locomotion is another obstacle. Daydream can use its proprietary touchpad to provide directional input, allowing you to easily navigate or rotate in any direction. Cardboard users need a different method to achieve the same effect, so we have been testing movement solutions by having the user click on open areas on the floor. If it’s a valid position the user will automatically navigate there using the navmesh system (a Unity 3D feature that enables automatic pathfinding). Additionally, the user can optionally rotate their view by using UI rotation buttons, which situationally activate when the user turns their head far enough to the side. By incorporating these solutions, Cardboard users will be provided a hands-free locomotion solution that is similar to Daydream. In an academic environment, multi-platform support is critical to insure all students can access learning materials, regardless of their device type and platform. With that in mind, we are also developing non-VR usability for any mobile device- we’ll detail that in a future post.
Please share your thoughts. We’re interested in what other folks are experiencing with Daydream, Cardboard, and VR in general.
Additional Dev Notes From Jon Bowen:
- Daydream allows selection of items that you are not directly looking at. The cardboard reticle is tied to the center of your screen.
- Daydream allows additional input using clicky d-pad, and multiple buttons. Cardboard has, at most, a single button.
- Daydream can use the d-pad for touch gestures such as swiping. This functionality must be incorporated using on-screen buttons for cardboard.
- Creating a unified interface for both daydream and cardboard, so instructors can explain it, and the experience switching between the two is seamless is important. A user needs to be able to utilize the same base control scheme while providing advanced features for daydream use.
- Daydream certified phones are much more powerful than the base requirements for cardboard. Scenes must be designed with low-end hardware in mind.
- I removed the physics-based controls from the daydream elements controller to avoid problems with items getting stuck or lost. Learning software should never be frustrating, there is generally less of a desire to use it in the first place, and contextually, more opportunity for frustration.
- I created a separate base class for cardboard objects and redeveloped the fuse timer to make it as accessible as possible.