Interactive footprint display method

In this research, we propose a technique for representing footprints in real time in an interactive system such as a virtual reality (VR) or 3D game system. To increase data updating speed during interactive operations, this method represents footprints by using rectangles on which a foot-shaped texture is mapped. And the method arranges the rectangles dynamically along the movement path. However, since the number of rectangles that must be drawn increases as time elapses, footprints represented by the rectangles are transformed to footprints represented by the floor texture that does not entail drawing costs, by overwriting footprints onto the floor texture in existence. The transformation is done when operations are interrupted such as scene changes. For movement over a wide range, it is difficult to store all floor textures on memory. As a result, the footprint positions and directions are recorded in advance, and only the floor textures that must be drawn are generated. At this time, since new footprints remain distinct, their positions and directions are recorded as time-series data, and footprints are reproduced accurately from those data. On the other hand, since footprints for which time has passed fade, their positions and directions need not be reproduced accurately. Therefore, the amount of data is held to a fixed amount by discretizing the positions and directions and recording the numbers of footprints. In this way, footprints can be displayed and updated in real time by switching the display method and data representation method according to the scene. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(10): 36–46, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20310