The Great Divide: Comfort and Realism
Summer 2014, Oculus DK2 + Razer Hydra
VR dev kits were being released to the public in droves, now with positional tracking, and people were getting motion sick. Just by putting on a headset, it became an immediate uphill battle for comfort. Using your hands and body, standing up and crouching down—it had all added so much to presence. But it had come at a cost. Any time the camera moved without the player, it was barf city. And in an exploration game like The Gallery, you couldn’t just explore the contents of your chair.
Most locomotion in VR was now split between ‘Body Cart’, ‘Tank Move’, and ‘Stick Move’ with yaw rotation. The latter was the worst of the bunch, not only producing artificial forward-backward movement (vection), but also allowing the player to control the camera independent of their head position. Instead of the Body Cart, your face was the one along for the ride. If motion sickness was going to be the widespread problem it was trending to be, we would need to find a better way.
In any given moment, the human eye is capable of what’s called a ‘saccadic movement.’ Your eyes are constantly dancing, looking around for other things, even though to you it seems like the movements are smooth or even still. It’s an imperceptible movement—a jump. This was the basis for VR ‘Comfort Mode’.
Rather than continuously rotating the camera over a duration, as yaw rotations do, Comfort Turns are instantaneous. You press a button, or flick the control stick, and the player camera changes its facing direction. And because it’s instantaneous, there’s no visual motion for your brain to perceive, and no physical movement for your inner ear to detect—no vestibular disconnect. It goes a long way to mitigating motion sickness, and the option has remained a standard for comfort even in today’s evolved VR experiences.
At the same time, we were still trying to make sure moving felt like moving. We began to work on a VR obstacle course specifically to experiment with different locomotion styles. I went back to climbing, inspired by geodesic domes, and developed a spherical ladder that you could go all the way around. You would grab for a bar and latch up, climbing the ladder until you were looking down at the ground in front of you, before reaching a point of upside down on the other side of the dome.
That one never made it in either, but if you’re reading this, NASA, you know who to call.
There’s Always a Lighthouse
Winter 2014, SteamVR + V minus-1
Near the end of 2014, Valve invited us and a few other select developers to a secret summit. It was there that they revealed SteamVR (and what would eventually become the HTC Vive) for the first time. Rather than the heuristic, inside-out tracking points Valve had shown at Dev Days earlier in the year, SteamVR was using real, local points on the HMD tracked within a volumetric space via ‘Lighthouses.’
SteamVR did something else no other HMD of the time had before: it added hands. Instead of being tethered to a small magnetic box in front of you, controllers could now be tracked spatially by the same Lighthouse hardware as your head. It offered the genuine ability to physically walk around and touch things in VR. It was simply amazing.
It also threw everything we knew—and every concept we had for our game—out the window.
When the player was fixed in their meatspace (their physical space), that was a fixed local offset. We had designed climbing so that when a player grabbed onto a bar we calculated that offset. With roomscale, those constraints were gone—you could move anywhere. Now, if the player decided to move positionally mid-grab, their arm would outstretch and essentially break free from the ladder and the offset. We were calling and calculating a redundant position that was now tracked by hardware right out of the box.
Likewise, Tank Move became irrelevant. You could walk in any direction in meatspace while simultaneously looking around normally. Our whole book on locomotion and body persistence broke overnight. The entire game halted. From that point, we had three months to not only redesign everything we had, but miraculously hit a new benchmark of 90fps for the first public demo of SteamVR at GDC 2015.
The first thing I remember us brainstorming about for the GDC Demo was movement. We had always wanted the player to move, and even though SteamVR had introduced this larger, volumetric space, it was now just a bigger box. Our plan was to utilize the volume itself as a virtual elevator, so that the whole room could move upward—and you with it.
As the GDC Demo concluded to the sweeping score of Jeremy Soule, the elevator rose up, and the walls opened on all sides to reveal a skyline with infinite possibilities and directions to explore.
