Spacehopper is a large-scale, floor-projected version of the classic 1979 arcade game Asteroids where players bounce on a hopper ball to control their ship. We follow the same rules as the original game: asteroids break into smaller ones once hit, the game spawn flying saucers over time and as the game progresses the amount of spawned asteroids increase.

The game has two game modes:

  • Gravity wave: players bounce on the ball to create a gravity wave that repel asteroids away.
  • Laser shot: players bounce on the ball to shoot a laser similar to the original game.

Spacehopper was implemented using Unity3D engine and the Dalhousie Top-Down Tracker. We performed a user study during the 2017 edition of the Nocturne art festival, at the Halifax Waterfront. Spacehopper was also an interactivity exhibit at CHI 2018.

Very large floor displays can promote engaging public experiences, but incur perspective-related warping, making it challenging to comprehend and interact with distal objects when standing on the display. We used SpacHopper to explore a perspective compensated view technique that maintains the relative size and shape of objects as they move away from the viewer. Players bounce on a hopper ball to control their ship in one of two control modes: bounce to repel or bounce to shoot. We recruited 59 participants during Nocturne, finding that perspective compensated view yielded longer playing times (and higher scores) in the bounce to fire modality. Bystanders were highly engaged with players and also seemed to be unaware of the perspective warping, suggesting that visually compensating for the interactor’s perspective does not adversely impact the enjoyment of passive participants and audience members, at least under some circumstances. More details can be found in our IMX 2020 paper.

Juliano Franz, Joseph Malloch, Vinicius Sanches, Derek Reilly: SpaceHopper: Bounce Your Way to Galactic Domination. Proceedings of the ACM SIGCHI Conference Extended Abstracts on Human Factors in Computing Systems (CHI EA 2018), ACM Montreal, Canada, 2018.
Juliano Franz, Joseph Malloch, Derek Reilly: Compensating for Perspective-based Distortion on Large Interactive Floor Displays: the SpaceHopper Field Experiment. In: Proceedings of the ACM International Conference on Interactive Media Experiences (IMX 2020), ACM, 2020.