Continuing our series of occasional interviews with game developers about current and upcoming hardware and game graphics engines, we chat with Marko Kylmamaa, senior graphics programmer for Digital Illusion' Canadian studio.
FiringSquad: First, Intel and AMD are pushing dual core processors and within the next year four core processors are due to be released. How will DICE support this kind of tech in the Battlefield 2/2142 engine and will there be any need for special programming to fully support multi core CPUs in PCs?
Marko Kylmamaa: While a program geared towards a single-core machine may run fine, with some exceptions, and perhaps even somewhat faster on a multi-core machine, in order to realize the real performance benefits a careful attention has to be paid into structuring the code for the correct granularity in mind, to make it suitable for multi-core execution. With the introduction of the next generation consoles and the PC hardware, the whole industry is in a learning phase for understanding the differences between the traditional multi-threading approaches, and multi-threading for multiple cores. DICE is working closely with hardware vendors in making sure that all of the future titles make the maximum use of the available multi-core architecture.
FiringSquad: The 64-bit CPU has taken longer to really appear in mainstream PCs than some people expected. Do you think 64-bit CPUs will become more popular and how does DICE support it in their Battlefield 2/2142 engine ?
Marko Kylmamaa: One of the problems with harnessing the full power of 64-bit CPU’s is the lack of adoption of 64-bit operating systems. Due to this it’s difficult for the game developers to make full use of the 64-bit execution potential without providing a separate set of executables compiled for the different operating systems. The current Battlefield 2 technology has been thoroughly tested on the 64-bit architecture for guaranteeing a solid performance, and optimizations have been made where possible with such architectures in mind.
FiringSquad: Game physics are getting more and more attention as well with more attention being put into destructible objects and better collisions. Where does DICE stand on this kind of support for its engine and what solution is best; having a dedicated card (AGEIA) using a graphics card (ATI/Havok) or using a CPU to handle it?
Marko Kylmamaa: Especially with multiplayer games in mind, it is difficult to make use of scaleable physics, since especially from the gameplay perspective all of the players must experience the same end result in simulation regardless of their hardware. This leads to a lot of the scalability of the physics being used for visual effects such as richer particle effects or fluid simulation. The GPU can of course be used for offloading the physics simulation from the CPU, but this will compete with the remaining processing time for graphics. Therefore in most cases it is necessary to strike the right balance between the CPU and GPU usage with the needs of the particular game in mind. The next generation technology at DICE is being built on the bleeding edge and will make use of very comprehensive physical modeling.
FiringSquad: HDR lighting is also getting a lot of attention in more PC games. How does the Battlefield 2/2142 engine support those features and how will that help the graphics in games that use it?
Marko Kylmamaa: HDR lighting can add significantly to the perceived realism in the modern graphics engines. It is becoming an increasingly common feature as the new hardware supports full floating point surfaces and has the required processing power for supporting a multitude of such high end features.
Some aspects of the HDR lighting were simulated especially in the Battlefield 2 – Expansion Pack: Special Forces, for adding a degree of realism to the night-time look. The effect is fairly settle and was used mainly for fine tuning the overall look. Battlefield 2142 does not have night-time levels, so the same technology was not applicable to it, however there are a great number of special lighting effects for enhancing the desired futuristic look of the game.
FiringSquad: More and more games are using extensive pixel and vertex shading for visual and art effects. How does the Battlefield 2/2142 engine support these features currently and how will pixel and vertex shaders be used in the future, particularly with Windows Vista and DirectX10 support?
Marko Kylmamaa: The Battlefield 2 engine has been built on the DirectX9 architecture and is a fully shader based model. This allowed for a great flexibility during the development, and not supporting the older fixed function pipeline model allowed us to concentrate solely on the high end features. Battlefield 2142 is based on the improved Battlefield 2 technology and will be released later this year, so considering that the DirectX10 hardware won’t be widely available just yet, it hasn’t been beneficial to re-architect the engine into a DirectX10 based model for this release. This allowed the available time to be used for adding a number of new special effects and polishing the overall look of the existing engine.
FiringSquad: What other advanced hardware and graphical features do you think will be supported in upcoming Battlefield 2/2142 engine games and in future graphics engine?
Marko Kylmamaa: Battlefield 2142 will support a large range of high end special effects geared towards creating the desired futuristic look. These involve for example new atmospheric effects for creating a unique look that is quite different from Battlefield 2.
FiringSquad: Finally, Mark Rein from Epic has said that Intel is hurting the PC gaming industry through its use of intergrated graphics in PCs. Is this a real threat and if so what can be done about this from the game developer's side?
Marko Kylmamaa: Intel produces what you could call the ultra-low end graphics cards for a market segment that typically doesn’t wish to invest the money into a higher end, gaming geared hardware. Clearly there is a demand for this type of hardware as Intel’s graphics cards boast a large user base. However, this does impose challenges for the games industry in our attempts at reaching especially for the casual gamer market. Hardware requirements for the next generation games keep growing faster than what is needed for running general applications, which increases the rift between the casual and hardcore hardware markets. I believe that we as an industry will also have to recognize the different requirements these markets impose.
From the perspective of a developer, it can be difficult or in some cases practically impossible to make the high-end game run on the ultra-low end hardware. Supporting such scalability range in performance could be prohibitive with the required development time and cost in mind. It is ultimately up to each developer to find the correct range of hardware which allows for the desired market penetration.