The world of graphics and graphics processors is a complex one, based largely on what we refer to as 'rasterization.' This is our industry's overly-complex way of saying that we can't quite make it happen the way it should, so there's a series of "best guesses" going on. Through rasterization, we can approximate many effects that we just don't have the processing power to represent more completely, through a method called raytracing.
Raytracing is something that many of the 3d and modeling afficionados will be intimately familiar with. Rather than just approximating things, raytracing involves physics calculations of each ray of light from a source through each volume of space, based on the volume's properties of refractivity, reflexivity, transparency, and other things. This technique is the proverbial 'holy grail' of graphics, as it is no longer 'guessing' - things become as real as you want to be, depending on how you control the properties of the textures.
Intel has been devoting lots of time lately to the advancement of raytracing, and has released a paper
showing that the technology really isn't too far off from being real-time. The study, done in 2005, showed a single-core P4 at 3.2Ghz being able to trace about 100 million segments per second and ran comfortably at 30fps. It goes on to state how raytracing will get 'interesting' when it can hit approximately 450 million segments per second. Unlike raster graphics, raytracing scales linearly with the number of cores devoted to it...so as we're looking at the upcoming Kentsfield processors, things are about to get interesting.
Of course, this only accounts for software solutions. Along with Intel's work, third party researchers at Saarland University have been developing 'raytace processors' or RPUs. These currently have speeds of only 66mhz, but can run some complex scenes at 512x384 resolution with speeds of up to 7.5fps. For the amount of math in raytracing calculations, that's pretty impressive.
You can read a nice summary of the work done over at ArsTechnica
, and stay tuned for some of our own thoughts on the issue.
Clearly, we're not going to be seeing commercial games running raytrace for 2006, or likely 2007. But what about 2008? Place your bets on the future of graphics in our forums