snapping

A common task in graphical user interfaces is controlling onscreen elements using a pointer. Current adaptive pointing techniques require applications to be built using accessibility libraries that reveal information about interactive targets, and most do not handle path/menu navigation. We present a pseudo-haptic technique that is OS and application independent, and can handle both dragging and clicking. We do this by associating a small force with each past click or drag. When a user frequently clicks in the same general area (e.g., on a button), the patina of past clicks naturally creates a pseudo-haptic magnetic field with an effect similar to that ofsnapping or sticky icons. Our contribution is a bottom-up approach to make targets easier to select without requiring prior knowledge of them.

We present the design of Lineogrammer, a diagram-drawing system motivated by the immediacy and fluidity of pencil-drawing. We attempted for Lineogrammer to feel like a modeless diagramming "medium" in which stylus input is immediately interpreted as a command, text label or a drawing element, and drawing elements snap to or sculpt from existing elements. An inferred dual representation allows geometric diagram elements, no matter how they were entered, to be manipulated at granularities ranging from vertices to lines to shapes. We also integrate lightweight tools, based on rulers and construction lines, for controlling higher-level diagram attributes, such as symmetry and alignment. We include preliminary usability observations to help identify areas of strength and weakness with this approach.