Chronos: A Tool for Interactive Scheduling and Visualisation of Task Hierarchies

Visualisation and structuring of tasks in a schedule, from relatively simple activities such as meeting scheduling to more complex ones such as project planning, has been traditionally supported by timeline representations similar to Gantt charts. Despite their popularity, Gantt charts suffer from a number of shortcomings, including poor representation of detail and inefficient use of screen real-estate, particularly when a large number of parallel tasks, each of which requiring its own representation space, need to be displayed. We have devised an alternative visualisation, called temporal mosaic, which addresses some of these shortcomings while utilising space more efficiently. We have shown that as a static visualisation temporal mosaics outperform Gantt charts in terms of their ability to convey time-based scheduling information to users engaged in various temporal inference tasks. This paper extends that research by presenting interactive techniques which support creation, and dynamic visualisation of task hierarchies and relationships. These techniques are illustrated through a system for direct manipulation of schedules in both Gantt chart and temporal mosaic formats.