The processes and methods used in the creation of games are often significantly different from conventional software engineering approaches. In this paper, the authors propose a research methodology for game design, framed as a way of systematically documenting design space exploration for a game.
Game designers create a trajectory through the problem space spanned by the decisions about various design aspects of the game. The authors suggest that by carefully documenting this trajectory through descriptive means (such as design diaries, or documents describing deliberations and decisions about the game), research can be conducted about game design itself. GitHub and similar code repositories offer a practical means of collecting much of this information in a systematic way, in particular game builds. If such repositories can be made publicly available, game design researchers can use them in their investigations.
As the authors acknowledge, this is not appropriate for commercial game development. However, even in academic environments, the quantity and quality of material in a repository is often limited. In contexts like hackathons or student projects, the emphasis often lies in the quick creation of a playable prototype, at the expense of documenting the underlying design choice trajectories. User feedback, or insights gained from observing users of early builds, can also influence design decisions without being reflected in documents.
For these reasons, it is not surprising that finding suitable methodologies is in its early stages. Clearly, efforts from related disciplines such as human-computer interaction, user-centered design, software engineering, and ethnography can serve as additional starting points, and the authors are well aware of research in those areas.