Fluid DTMouse: better mouse support for touch-based interactions

Although computer mice have evolved physically (i.e., new form factors, multiple buttons, scroll-wheels), their basic metaphor remains the same: a single-point of interaction, with modifiers used to control the interaction. Many of today's novel input devices, however, do not directly (or easily) map to mouse interactions. For example, when using one's finger(s) or hand directly on a touchable display surface, a simple touch movement could be interpreted as either a mouse-over or a drag, depending on whether the left mouse button is intended to be depressed at the time. But how does one convey the state of the left mouse button with a single touch? And how does one fluidly switch between states? The problem is confounded by the lack of precision input when using a single finger as the mouse cursor, since a finger has a much larger "footprint" than a single pixel cursor hotspot. In this paper we introduce our solution, Fluid DTMouse, which has been used to improve the usability of touch tables with legacy (mouse-based) applications. Our technique is applicable to any direct-touch input device that can detect multiple points of contact. Our solution solves problems of smoothly specifying and switching between modes, addressing issues with the stability of the cursor, and facilitating precision input.