On the comprehension of application programming interface usability in game engines

Abstract

Extensive development of games for various purposes including education and entertainment has resulted in increased development of game engines. Game engines are being used on a large scale as they support and simplify game development to a greater extent. Game developers using game engines are often compelled to use various application programming interfaces (APIs) of game engines in the process of game development. Thus, both quality and ease of development of games are greatly influenced by APIs defined in game engines. Hence, understanding API usability in game engines could greatly help in choosing better game engines among the ones that are available for game development and also could help developers in designing better game engines. In this article, we thus aim to evaluate API usability of 95 publicly available game engine repositories on GitHub, written primarily in C++ programming language. We test API usability of these game engines against the eight structural API usability metrics—AMNOI, AMNCI, AMGI, APXI, APLCI, AESI, ATSI, and ADI. We see this research as a first step toward the direction of improving usability of APIs in game engines. We present the results of the study, which indicate that about 25% of the game engines considered have minimal API usability, with respect to the considered metrics. It was observed that none of the considered repositories have ideal (all metric scores equal to 1) API usability, indicating the need for developers to consider API usability metrics while designing game engines.