Still about Situation Awareness, via An Exploration of Techniques to Improve Relative Distance Judgments within an Exocentric Display from Gina Crvarich :

Situation awareness consists of several components, including spatial awareness. Spatial awareness refers to an individual's understanding of the three-dimensional (3D) geometry of a particular environment. The need for adequate spatial awareness can range from military mission applications, where understanding the relative position of allies and enemies is important, to medical applications where understanding the relative location of organs and tumors within the environment of a human body is critical. In general, spatial awareness becomes vital when someone needs to understand the spatial relationships of elements within an environment in order to effectively accomplish a mission or task. Virtual environment interfaces provide many approaches for representing 3D space and thus may be useful in communicating spatial awareness so that an individual may successfully complete the intended mission.

The research focuses on the re-creation of several specific depth and distance cues in order to see their effect on relative distance judgments made within a computer-generated 3D space. The goal of this research is to determine each feature's effect on making relative distance judgments so that recommendations can be provided for those individuals designing 3D exocentric spatial displays.