Open Source Technology for Massively-Multiplayer Games Case Study: OGRE as an Massively-Multiplayer Graphics Engine Student: Davíð H. Brandt ([email protected]) Instructor: Hannes Högni Vilhjálmsson Reykjavík University, T-615-SVER Independent Studies, Fall 2009 Executive Summary Free-and-open-source-software (FOSS) promises an attractive alternative to the ever-increasing costs of commercial middleware, which threatens the profitability of modern game development. As MMO development is typically an order of magnitude more expensive than classical game development, this promise seems even more attractive within this sub segment of the industry. There is however little evidence of widespread FOSS usage within the gaming industry. This paper attempts to shed light on some of the underlying reasons through performing an in-depth evaluation of the OGRE open-source rendering engine from the perspective of an MMO developer. The author shows that there are great savings to be had when using the engine as a foundation when compared to building a proprietary rendering engine from scratch, but it does not actually offer significant cost advantages over commercial alternatives in the context of MMO development. The engine also comes with the added risk that it is virtually unproven in the field of high-end gaming, although a number of low-end and mid-range games based on the engine have shown great promise. Furthermore, while OGRE is highly praised by industry professionals it is however uncompetitive in high- performance gaming due to its lack of parallelism. The author concludes that while using OGRE as a rendering engine in a high-end MMO is almost certainly doable, unquestioning commitment to the engine would be folly. Reykjavík University, T-615-SVER Independent Studies, Fall 2009 Page 2 Contents Executive Summary ....................................................................................................................................... 2 1. Introduction ............................................................................................................................................... 6 2. About the author ....................................................................................................................................... 7 3. OGRE games reviewed .............................................................................................................................. 8 3.1. Alliance: The Silent War ..................................................................................................................... 9 3.2. Torchlight .......................................................................................................................................... 10 3.3. Motorm4x ......................................................................................................................................... 11 3.4. Zombie Driver ................................................................................................................................... 12 3.5. Pacific Storm ..................................................................................................................................... 13 3.6. Jack Keane ........................................................................................................................................ 14 3.7. Venetica ............................................................................................................................................ 15 3.8. Earth Eternal ..................................................................................................................................... 16 3.9. Project Wish ..................................................................................................................................... 17 3.10. Origins of Humanity ........................................................................................................................ 18 3.11. The Legend of Crystal Valley .......................................................................................................... 19 3.12. Amateur gaming ............................................................................................................................. 20 3.13. Off-the-shelf game-engines using OGRE ........................................................................................ 21 3.13.1. StemCell Engine based games ................................................................................................. 22 3.13.2. NeoAxis Engine based games .................................................................................................. 23 3.14. Summary of OGRE game reviews ................................................................................................... 27 4. Developer interviews............................................................................................................................... 28 4.1. Choosing OGRE ................................................................................................................................. 28 4.2. Comparing OGRE to commercial alternatives .................................................................................. 29 4.3. Mastering OGRE ............................................................................................................................... 29 4.4. Establishing a content pipeline ........................................................................................................ 30 4.5. OGRE’s Performance ........................................................................................................................ 30 4.6. OGRE and 3rd party middleware ....................................................................................................... 31 4.7. The downside of OGRE ..................................................................................................................... 31 4.8. The upside of OGRE .......................................................................................................................... 31 4.9. Team-specific questions ................................................................................................................... 32 4.10. Summary of developer interviews ................................................................................................. 33 Reykjavík University, T-615-SVER Independent Studies, Fall 2009 Page 3 5. Cost-benefit analysis ............................................................................................................................... 34 5. 1. Immediate costs .............................................................................................................................. 34 5. 1. 1. Qualification costs ................................................................................................................... 34 5. 1. 2. Licensing costs ......................................................................................................................... 35 5. 1. 3. Training costs ........................................................................................................................... 35 5. 1. 4. Production costs ...................................................................................................................... 36 5. 1. 5. Opportunity costs .................................................................................................................... 36 5. 2. Benefits ............................................................................................................................................ 38 5. 2. 1. Time benefits ........................................................................................................................... 38 5. 2. 2. Cost benefits ............................................................................................................................ 39 5. 2. 3. Focus benefits .......................................................................................................................... 39 5. 2. 4. Support benefits ...................................................................................................................... 40 5. 2. 5. Knowledge benefits ................................................................................................................. 40 5. 3. Real-world costs .............................................................................................................................. 40 5. 3. 1. External-process integration ................................................................................................... 40 5. 3. 2. Bugs or features? ..................................................................................................................... 41 5. 3. 3. Source-code access .................................................................................................................. 41 5. 3. 4. Verification, testing and the burden of development ............................................................. 42 5. 3.5. Business dynamics .................................................................................................................... 42 5.4. Quantified cost-benefit analysis ....................................................................................................... 43 5.5. ROI-adjusted quantified cost-benefit analysis ................................................................................