Applying Interoperability in Serious Games Environments Antoniu Ştefan 1, Ioana Andreea Stănescu 1, Ion Roceanu 2, Theo Lim 3 (1) Advanced Technology Systems - ATS, 222 Calea Domnească, Târgovişte, ROMANIA, ioana.stanescu@ats.com.ro; antoniu.stefan@ats.com.ro (2) Carol I National Defence University, 68-72 Panduri Street, Bucharest, ROMANIA, iroceanu@adlunap.ro (3) Heriot-Watt University, EH14 4AS, Edinburgh, SCOTLAND, t.lim@hw.ac.uk Abstract Standards have been subject of discussion in education environments for many years and their significance has been revealed by many researches and practitioners. As serious games emerge as a new opportunity for learning, standardisation and interoperability have become key interest points. Educational technology standards have tried to provide optimization patterns, but failed to reach their full potential, mainly because they have addressed particular issues and not an integrated perspective. To achieve success in SG interoperability it is important to consider the entirety of a SG Project development. This paper addresses the strengths and weaknesses related to the implementation of interoperability in serious games environments, with focus on development platforms, programming languages and target platforms. Keywords: Standards, Interoperability, Serious Games, 1. Introduction Building Serious Games (SG) is a challenging experience. It relies on highly creative processes that are immersive and consuming (Feil & Scattergood, 2005), and therefore standard-compliance does not seem to be a compatible approach to take when developing a SG Project. Considering the fact that even in companies with sufficient staff for programming, art and animation, game design, audio, and production, there is constant pressure to do more with less (Bergeron, 2006), standardization emerges as a necessary option to consider (Stănescu, Ştefan, & Roceanu, 2011). Interoperability, the ability of computers and applications to communicate and share resources in a heterogeneous environment, is dependable on standards. Optimizing requirements of accessibility, interoperability, durability, and reusability for maximizing cost efficiency starts with a proper understanding and integration of standards., or Sharable Content Object Reference Model, enables the sharing of distributed learning content across Learning Management Systems (LMS) that conform to (Robson Robby, 2010). Its development and implementation was clearly a vital first step in achieving the long-term vision of providing high quality training and education on demand (Gallagher, 2010). has become an international de facto standard in large measure because the goal was the establishment of a consensually negotiated foundation for a community to come together to address community goals: accessible, interoperable, durable, reusable content for learning and performance aiding (Roberts & Gallagher, 2010). To set a reference point for the evaluation of interoperability standards, a Serious Games Matrix (SGM) has been developed to compare key parameters of development platforms: strengths and weaknesses, targeted platforms, graphics, audio, sensors and other hardware, communication, as well as if a certain development platform is interoperable with the LMS using.
94 University of Bucharest and "Transilvania" University of Brasov The SGM has been applied for several SG development platforms with the purpose of highlighting the key elements that enable the development of interoperable SG solutions based on. This paper details the findings of the analyses conducted on four development platforms: C, C++; Java,.NET Framework; and Mono. This research was funded under the European Community Seventh Framework Programme (FP7/2007 2013), Grant Agreement nr. 258169. 2. Serious Games Matrix The SGM has been developed to enable the analysis of applicability from the point of view of different development platforms and provide guidelines to SG developers. Linux (desktop distributions such as Ubuntu, Debian, Redhat, etc.) Native code C, C++ Widely used programming language. Low memory footprint. Direct access to hardware and high level of control over resource utilization. Various licensing options available depending on development environment and libraries used. Source level compatibility across a wide range of target platforms from handhelds to game consoles and embedded systems. A superset of C++ called Objective-C is the main development language for ios It's important to note that such a low level programming language is very limited in the number of libraries and APIs that are inherently included. Developers have the option of building everything from scratch for complete control or to integrate additional libraries and frameworks. While there is a very high degree of source code compatibility, it is up to the developer to build interfaces that map platform specific structures and APIs in an abstract manner, and each external library/framework used must also be portable. Compared to regular Windows based development, additional restrictions apply because the Win32 APIs are not available for ARM processors and games developed for Windows RT can only be developed using the WinRT APIs and the Metro style interface No. Unless the code is packaged as a plugin which is installed and hosted in the web page, in which case the plugin must be independently ported for each operating system and browser plugin architecture (ActiveX, NPAPI). Google Chrome offers a partial solution to this problem using the NaCl (Native Client) platform Limited source level compatibility. Code can be ported and reused as a library through the NDK (Native development kit) but it has to be integrated into a Java based application. Current devices all use the ARM architecture but with the emergence of devices based on Intel processors, native code must be ported between the two processor architectures No limitations, but support must either be coded from scratch,
The 7 th International Conference on Virtual Learning ICVL 2012 95 provided by the target platform (DirectX, OpenGL) or through additional libraries Interoperable with the LMS No. See description for targeting deployment using Table 1. : C, C++ Java Java High level programming language with built in garbage collector. Compiles into platform independent byte-code allowing the same binary to server multiple operating systems and architectures. It is also the main developing language for. Requires more resource than games developed using native code. In terms of actual game development it is still very low level compared to dedicated game engines., binary level compatibility, except Java Native Interface No Linux (desktop distributions such as Ubuntu, Debian, Redhat, etc.), binary level compatibility, except Java Native Interface, binary level compatibility, except Java Native Interface (Windows, OS X, Linux). Requires the Java Runtime Environment browser plugin No. APIs and implementation differ from Java SE but there is a high degree of code reusability No limitations. 2D and 3D acceleration provided. Additional features through libraries No limitations. Some basic formats and support provided. Effects and hardware acceleration can be implemented through additional libraries No limitations. Implemented through additional libraries or native code calls Table nr. 3. : Java No limitations. Full IP support built-in. Same requirements as for deployment
96 University of Bucharest and "Transilvania" University of Brasov.NET Framework C#, VB.NET High level managed programming language with built-in garbage collector. Source code can be partially reused in Mono based projects Requires more resource than games developed using native code. Code targeting.net is only suitable for deployment on Windows. In terms of actual game development it is still very low level compared to dedicated game engines, except code that uses P/Invoke. Also, games need to be built for the new Metro style interface Linux (desktop distributions such as Ubuntu, Debian, Redhat, etc.) No. Some parts of code can potentially be ported using Mono No. Some parts of code can potentially be ported using Mono No. Partial source code reusability in Silverlight projects No. Some parts of code can potentially be ported using MonoTouch No. Some parts of code can potentially be ported using Mono for Table 3..NET Framework No limitations. 2D and 3D acceleration provided. Additional features through libraries No limitations. Some basic formats and support provided. Effects and hardware acceleration can be implemented through additional libraries No limitations. Implemented through additional libraries or native code No limitations. Full IP support built-in No. See description for targeting deployment HTML5 / CSS / JavaScript JavaScript Platform independent development with support for any modern web browser. No royalties or fees required to develop and distribute games
The 7 th International Conference on Virtual Learning ICVL 2012 97 Linux (desktop distributions such as Ubuntu, Debian, Redhat, etc.) Limited in processing power (no multi-threading) and hardware interfaces available. Code runs sandboxed and cannot access native code or hardware interfaces. Apps built on HTML + JavaScript are not features on mobile app stores, so they are subjects to less exposure to end-users Limited. acceleration is available only in some browsers. Video format support depends on browser: M, H.264 and/or Ogg Theora Limited. format support depends on browser: Wav, Mp3, Ogg Limited. Various implementations exist, but highly dependent on browser / platform Limited. Supports only HTTP(S) requests using AJAX Table 4. : HTML5/ CSS/ JavaScript Linux (desktop distributions such as Ubuntu, Debian, Redhat, etc.) Adobe Flash ActionScript Platform independent development with support for a great number of devices. Built around web technologies and uses a scripting engine similar to JavaScript Limited processing power compared to native code or managed code. Code executes in a sandbox and cannot be elevated to access native code or hardware devices. Authoring tools are not free. Vendor lock-in. No. However, Adobe announced that it will stop producing new versions of the NPAPI Flash plugin for Linux. This currently leaves Google Chrome as the only browser with support for future versions of Flash, and possibly other browsers if they implement the PPAPI interfaces developed by Google
98 University of Bucharest and "Transilvania" University of Brasov (Windows, OS X, Linux). Requires plugin. Experimental support for converting to HTML5 + JavaScript. Flash projects need to converted specifically for ios. Requires plugin, which is rather resource intensive for mobile devices Limited. 2D and 3D acceleration provided. Compatible with H.264 and some other proprietary formats Limited. Basic support provided. Compatible with MP3 and AAC formats Limited. Accelerometer support included Limited. Partial TCP/IP support included. Same requirements as for deployment Table 5. : Adobe Flash The analyses carried out using the SGM have shown that there is no one-size-fits-all approach when choosing a serious game development platform. Although at first glance, web-based open standards seem to cover a wide range of use cases and deployment scenarios, there is still a long way to go before these technologies mature enough to be comparable in performance with native code development. More and more developers (e.g. Facebook) are scaling back web based development for mobile platforms in exchange for native apps which perform better and are better integrated into the overall mobile ecosystem. 3. Conclusions Interoperability standards impact the design and development of serious games. Some standards are overlapping, while others are independent. Some standards complicate the development of serious games, yet the lack of a universal interoperability standard often hampers development. The SGM has been developed in order to establish a reference point for evaluation and facilitate the development of punctual recommendations and interventions that enhance SG interoperability. The authors analyse five development platforms using the SGM, to identify their strengths and weaknesses, as well as their interoperability potential in SG ecosystems. Future research will focus on applying the SGM to other development platforms, in order to support the development of sustainable SG interoperability solutions. The SGM will be extended in order to assist those SG Projects were the development model cannot be applied, and provide alternative options, such as IMS LTI or TinCanAPI.
The 7 th International Conference on Virtual Learning ICVL 2012 99 4. References Feil, J., & Scattergood, M. (2005). Beginning Game Level Design. Boston, MA: Course Technology PTR. Bergeron, B. (2006). Developing Serious Games. Cengage Learning. Stănescu, I., Ştefan, A., & Roceanu, I. (2011). Interoperability in Serious Games. In R. Ion (Ed.), else - elearning and Software for Education. 1, pp. 19-24. Bucharest: Edituta Universitara. Robson Robby, R. T. (2010). Standards The Agony and the Ecstasy of ADL. In J. P. Wisher R., Learning on Demand: ADL and the Future of e-learning. Alexandria, VA: Advanced Distributed Learning. Gallagher, P. (2010). The Development of. In J. P. Wisher R., Learning on Demand: ADL and the Future of e-learning. Alexandria, VA: Advanced Distributed Learning. Roberts, E., & Gallagher, P. (2010). Challenges to. In J. P. Wisher R., Learning on Demand: ADL and the Future of e-learning. Alexandria, VA.: Advanced Distributed Learning.