2.2 Experimental Setup

The landscapes were presented as virtual island environments created using Unity3D game engine software on a 2008 Mac Pro with a 30” screen, and rendered at a resolution of 2133x1600 pixels. Participants were seated two feet away from the display, which comprised 60 degrees of visual angle. Water was rendered outside the virtual island terrains, and participants were unable to move beyond these circular boundaries. Participants navigated an avatar through the confines of the circular environments from a first-person perspective using a PlayStation 3 controller. The virtual island environments were rendered at a scale of 200 meters in diameter, with the maximum height of the landscape set to 50 meters. Participants could move their avatar around the flat surface of each island, as well as over terrain of an incline less than 45 degrees. Elevated terrain prevented participants from seeing from one end of an island to the other, except for the D=1.0 islands. In some experimental conditions, a topographic map of the island was displayed for use in navigation. Four examples of a participant’s view from the displayed environment are presented in Figure 3.

Examples of first-person perspective views in Condition 2 (Map). The D of the landscapes are 1.1 (top-left), 1.3 (top-right), 1.7 (bottom-left), and 1.9 (bottom-right). The displayed map is shown to participants in certain experimental conditions described below. The red dot on the map indicates the position of a target object.