Fastbrain was a prototype game that I created for a client out of UC Davis. The client was looking to create a game that relied on some of their research to help treat individuals with certain cognitive disorders. We worked together to design mechanics that were faithful to the treatments they had already developed, but were still fun and engaging. Eventually, that client and I translated the mechanics from this prototype into virtual reality, and created the foundation for Cognivive.
One of the more fun challenges I faced in creating Fastbrain was designing the game’s calibration feature. In order for the therapeutic aspect to be effective, the game needed to understand how much of a player’s vision an object would take up. The so-called “angular size” of an object is a function of its physical size and its distance from the viewer. Since Fastbrain was designed to be played on a screen of any size, by a player sitting an unknown distance away from it, we needed a clever way to determine those data points. The solution came from the field of anthropometrics. A typical human’s arm length is closely related to the size of their hands and their fingers. For the average person, if they hold up their thumb at full arm’s length, their thumb subtends about 2 degrees of visual angle. Using this fact, we designed a brief calibration scene where we asked the player to make that thumbs up gesture and resize a game object until it was just hidden by their thumb. From there, we were able to determine exactly what the “angular size” of every object in the game was.