The implicit fan cursor

Abstract

We present the Implicit Fan Cursor (IFC) -a novel target pointing technique using a cursor with a fan-shape activation area. The IFC couples the cursor's activation area with its velocity, i.e., the speed and direction of the mouse motion, behaving like a 2D spotlight cursor at low speed and a circular area cursor at high speed. Thus, it enables the user to precisely acquire distant targets at low speed and easily acquire nearest targets at high speed, without explicit mode switching. This technique minimizes cursor movement, while taking into consideration of the precision of cursor movement at different speeds. It also ensures that only one target is captured at any time. The results of our controlled experiments show that the IFC outperforms the point cursor and the area cursor techniques, particularly in terms of cursor moving distance, and that its performance can be accurately modeled using the Fitts' law.

Target Expansion Lens

“…The secondary information slows down the transfer phase because the closed-loop feedback control (1) processes the provided information and (2) identifies the primary information from the secondary information. As the transfer phase is likely to be the longest goal-oriented phase, we explain most of the performance differences observed between target expansion techniques [2,6,7,20] by the impact of the secondary information on the transfer time: It is hence Not the More Visual Feedback the Better!…”

“…Finally, according to the Stochastic Optimized Sub-movement Model, the closed-loop feedback control of the corrective submovements allows the users to benefit from an expanding target even if this target expands unexpectedly and at the very end of a pointing movement. Consequently, with target expansion, Fitts' law models the pointing time if we consider the expanded target size (W X ) instead of the initial target size (W) [2,3,5,11,20,23]. This has been shown to be reliable even when the aimed target is unpredictably expanded and the cursor has traveled 90 % of the distance to the target [3,11,23].…”

“…We first present 6 techniques that are based on a Voronoi tessellation for the expansion algorithm (see introduction section). We then present 2 versions of Implicit Fan-Cursor [20], which use an expansion algorithm allowing shorter -and thus faster -pointing movements than the algorithm based on a Voronoi tessellation.…”

“…A basic version of IFC includes a single crosshair with an highlight of the designated target. Two visual aids have been studied for this technique: a circular-shape as with Bubble Cursor (implicit continuous cursor-based) and a fan-shape (implicit continuous cursor-based) which is a slice of the circular-shape oriented along the direction of the cursor's movement [20]. These two visual aids performed differently, while conveying the same target expansion and while being described by the same values along the 3 axes (implicit continuous cursor-based).…”

“…The study of the starting phase implies that the users do not know where the target is. As opposed to several previous studies [2,5,6,7,20] and in order to force the participants to look at the goal target, we modified the ISO 9241-9 [10] pointing tasks as follows. Eight goal targets were regularly distributed along a circle.…”