Tom Clancy's Ghost Recon Advanced Warfighter 2 hit the 360 back in March to strong praise, and now five months later it's set to hit the PlayStation 3 next week, complete with exclusive maps and weapons. We got a chance to chat with Olivier Didelot from Ubisoft Paris, the Lead AI Engineer on GRAW2 about the difference and challenges involved with developing a game simultaneously across the two different platforms.
Olivier, can you tell us how the development was handled between the PS3 & X360 versions?
Just after the original GRAW on X360 was released, the team began to work on GRAW2, simultaneously on the PS3 & X360 versions.
As the game engine (in-house YETI) was primarily built, in GRAW for the X360, the engineer team had a lot of work to do, to gain the same level of mastering on the PS3 hardware. Just as they did on X360 for GRAW1 before.
Since then, both teams have been working simultaneously on their versions, whether it's UBISOFT Paris & Red storm on the X360, or UBISOFT Paris & Shanghai on the PS3. How would you sum-up the specific differences between the X360 & PS3 development?
For an engineer, the two platforms are critically different, with different strengths & weaknesses. Moreover, we feel that there's a real difference in the philosophy behind it.
The very primary differences, in the way the processors are designed & combined or the way the memory is handled make them very different challenges for engineers.
This said, the GRAW engine was designed with cross-platform in mind, which allowed us to develop most of the game features whatever the platform and then, later on optimise them for a specific version.
It seems pretty difficult for the development team to port a X360 game to PS3... was that the case for GRAW2?
GRAW2 can't actually be seen as a port, as the two games were simultaneously developed.
As the hardware was so different, GRAW2 PS3 was an original development, which requires taking some time to think how you can get the most out of the console, goal being to provide the same experience for the end-users.
That time is used to come up with smart choices, most of them coming with the experience on how to use the hardware at its best.
That experience can extend depending of the platform exclusive features like the Achievements on the X360 Live or the Sixaxis controller on PS3 for instance.
How many people have been working on PS3 compared to the X360 team?
It's actually more complex than this. First, we had all the game, level & artistic design team working for both platforms, with specific task forces assigned to the aforementioned exclusives. Then on a technical point of view, a separate team has been working on the PS3 hard & software. The GRAW2 PS3 engine lead had actually already a strong experience on Playstation hardware but also was responsible for GRAW1 optimisations on X360.
Thanks to his experience, we've been able to make choices (like assigning a specific task to a specific core of the CELL) that tend to use the hardware to get the most out of it.
During the project, the teams exchanged best practices, at the code level. Some original decisions on the PS3 code actually made it through X360 and added a lot to the X360 version performances.
On the AI specifically, how different it is between the PS3 & X360 versions?
The code written for AI is actually exactly the same on both platforms. The differences lie in the way it's compiled & handled by the hardware. When we've made different choices, depending on the compared strengths of the components of each platform (using the CELL or one of the X360 core for specific tasks), it was just to secure high performances and will be totally invisible for the players.
AI has been a great area for improvement between GRAW & GRAW2, whether it's the team mates AI (which uses voice feedback to highlight enemies in the surroundings very precisely) or the enemy AI, which uses height & covers to surprise the player. This is a key to a tactical shooter experience success, and we really enjoyed the brute power offered by both platforms!
Anyways, the best to test it is to play the demos, already out for X360 & PS3 or to wait for the PS3 game release (with exclusive maps, weapons & Sixaxis support) next week!