Contents 1 Introduction
As recognition of the value of visualization has increased and the demand for visual analytics software has risen, visualization researchers have developed numerous software frameworks to meet these needs. By changing the cost structure governing the design and implementation of visualizations, such frameworks carry the potential to lower barriers to entry and increase the space of feasible visualization designs. Still, there is never a single tool or framework that is appropriate for all problems in a given domain. Developers often migrate between tools (e.g., when developing on a new platform) or build their own systems (e.g., to achieve functionality not available elsewhere). In either case, an understanding of the design solutions employed within existing tools could aid the programmer in learning and evaluating other frameworks and furthering their own development efforts. However, inspection of source code and design documents, if available, can prove difficult and tedious. Descriptions in the research literature often place more emphasis on novel features than on recurring design patterns. As a result, it can be difficult to identify, evaluate, and re-apply the design solutions implemented within existing frameworks.
