flexible timeline user interface using constraints
Authoring tools routinely include a timeline representation to allow the author to specify the sequence of animations and interactions. However, traditional static timelines are best suited for static, linear sequences (such MIDI sequencers) and do not lend themselves to interactive content. This forces authors to supplement their timelines with scripted actions which are not represented. Timelines also force frame-accuracy on the author, which interferes with rapid exploration of different designs. We present a redesign of the timeline in which users can specify the relative ordering and causality of events without specifying exact times or durations. This effectively enables users to "work rough" in time. We then implement a prototype and perform a user study to investigate its efficiency.
timeline prototyping constraint solving