Beating Fitts' law: virtual enhancements for pointing facilitation

We survey recent research into new techniques for artificially facilitating pointing at targets in graphical user interfaces. While pointing in the physical world is governed by Fitts' law and constrained by physical laws, pointing in the virtual world does not necessarily have to abide by the same constraints, opening the possibility for "beating" Fitts' law with the aid of the computer by artificially reducing the target distance, increasing the target width, or both. The survey suggests that while the techniques developed to date are promising, particularly when applied to the selection of single isolated targets, many of them do not scale well to the common situation in graphical user interfaces where multiple targets are located in close proximity. (C) 2004 Elsevier Ltd. All rights reserved.