Dramatic advances in 3D Web technologies have recently led to widespread development of virtual world Web browsers and 3D content.A natural question is whether 3D thumbnails can be used to find one's way about such 3D content the way that text and 2D thumbnail images are used to navigate 20 Web content We have conducted an empirical experiment that shows interactive 3D thumbnails, which we call worldlers, improve travelers' landmark knowledge and expedite wayfinding in virtual environments.

Virtual environment landmarks are essential in wayfinding: they anchor routes through a region and provide memorable destinations to return to later.Current virtual environment browsers provide user interface menus that characterize available travel destinations via landmark textual descriptions or thumbnail images.Such characterizations lack the depth cues and context needed to reliably recognize 3D landmarks.This paper introduces a new user interface affordance that captures a 3D representation of a virtual environment landmark into a 3D thumbnail, called a worldlet.Each worldlet is a miniature virtual world fragment that may be interactively viewed in 3D, enabling a traveler to gain first-person experience with a travel destination.In a pilot study conducted to compare textual, image, and worldlet landmark representations within a wayfinding task, worldlet use significantly reduced the overall travel time and distance traversed, virtually eliminating unnecessary backtracking.Landmarks are the subject of landmark knowledge, but also play a part in survey and procedural knowledge.In survey knowledge, landmarks provide regional anchors with which to calibrate distances and directions.In procedural knowledge, landmarks mark decision points along a route, helping in the recall of procedures to get to and from destinations of interest.Overall, landmarks help to structure an environment and provide directional cues to facilitate wayfinding. KEYWORDS: 3D thumbnails

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