Walls, Pillars and Beams: A 3D Decomposition of Quality Anomalies

Quality rules are used to capture important implementation and design decisions embedded in a software system's architecture. They can automatically analyze software and assign quality grades to its components. To provide a meaningful evaluation of quality, rules have to stay up-to-date with the continuously evolving system that they describe. However one would encounter unexpected anomalies during a historical overview because the notion of quality is always changing, while the qualitative evolution analysis requires it to remain constant. To understand the anomalies in a quality history of a real-world software system we use an immersive visualization that lays out the quality fluctuations in three dimensions based on two co-evolving properties: quality rules and source code. This helps us to identify and separate the impact caused by the changes of each property, and allows us to detect significant mistakes that happened during the development process.