1

2

itself dynamically according to their position (see Figure 2a). When the particle hits the line between participants, it gets “charged,” and if it hits one of the borders of the grid, that border (corresponding to the width of one of the squares of the grid) gets charged as well. The goal of the game is to charge opposing borders of the grid in order to light up the rows between borders (Figure 2b). If the particle hits one of the circles of a participant while they are standing above a charged part of the grid, the grid turns dark again. The goal of the game is to charge the whole grid. This game can potentially accommodate as many players as the projection surface would allow, each new player connected by a line to two other players (Figure 2c). Once the grid is completed, a new grid with a higher resolution (8x6 squares) appears, offering a more difficult challenge (Figure 2d).

I assumed that in order to create a game with more complex game mechanics, it could be beneficial to keep the interaction elements at their most simple and intuitive so as to encourage an easy entry and low learning curve barrier for players, who could then focus on discovering the more complex rules of the game. After my experience with MOVE, I realized that among all the different interactive gestures I had asked participants to perform while playing the six different game modules, the one that was the most intuitive and easy to understand was simply to move on the projected surface and have a circle position itself underneath them. When participants moved, the circle would follow them and reposition itself

with a slight delay underneath their feet. This simple relationship between player and visual graphic were used in the modules CHASE, HIDE, and AVOID, which were the games in MOVE that were the easiest for participants to understand without explanations.

Creating a game in which the only possible input from participants would be directional movement across a 2-D plane has led to successful gameplay mechanics in video games. The most famous example is maybe Pac-Man, an arcade game in which the player controls an animated mouth through a maze, avoiding ghosts and eating dots. A more sophisticated example using a 3-D space is Katamari Damacy, in which the player controls a small character pushing a sticky ball that increases in size as objects stick to it. The challenge resides in exploring the play area in search of objects to collect. Only objects smaller than the ball will stick to it, increasing the size of the ball and allowing players to collect increasingly bigger objects.

The second important reference to the concept of virtual ground is the idea of equilibrium, or negative feedback. In MOVE, the common gameplay mechanic behind each game module was that the longer players interacted with the game, the more the game increased in difficulty, eventually leading the player to lose. Ultimately, games were impossible to win, and were based on the typical setup experienced in early arcade games, where success was measured in high scores— in this case, how long players could last without losing. On

• Figure 2a. In Virtual Ground, a particle rebounds against a line connecting the players’ circles.

 

2

1

 

• Figure 2b. The goal of the game is to charge opposing sides of the grid by hitting them with the particle in order to light up the rows between borders.

 

2

1

4

3

 

• Figure 2c. Virtual Ground can be played by as many players as the projection surface allows, each new player is connected by a line to two other players.

 

2

3

1

May + June 2009

• Figure 2d. Once a grid of color is completed, a new grid with a higher resolution appears, offering a higher difficulty challenge.