As frequent readers of PC Perspective know, we have been very interested in the work of on Daniel Pohl, now an employee at Intel, that developed some of the first modern ray tracing gaming engines.  Daniel has written a couple of articles here on PC Perspective on the subject including Ray Tracing and Gaming – Quake 4: Ray Traced Project and Ray Tracing and Gaming – One Year Later.  I have also covered a lot of the technology behind ray tracing such as the Terascale processing cores that will probably power it in the future and the first real-time showcase of ray tracing by Intel at IDF 2007.

One of the interesting points in that last article was on the premise of how ray tracing can scale with hardware very easily and thus allow ray tracing engines to run on the high-end PCs as well as hand held systems.  At GDC last week Daniel showed off a version of the Quake 4 Ray Traced engine running on a 1.2 GHz single-core ultra-low power processor in a Sony VAIO micro-PC with a 512×256 resolution screen.  The engine scales very well on this slower platform simply because the resolution deems there to be much less work for the processor to handle:

“It’s because Ray-Tracing draws a scene in 3D by tracing rays of light from the pixels on the screen, to the surfaces of objects in view. And in the case of a UMPC, when one is viewing 3D space from the viewable area of a 4.5” LCD screen, fewer rays are required, and hence, the CPU requirements are substantially less. For example, you might prefer viewing a high definition (1280×720 resolution) display on your PC, but with the much smaller viewable area on a Sony* VAIO* UX Micro PC, smaller resolutions may be quite acceptable (such as 480×272, for example). Using this lower resolution, it would only require 8% of the CPU requirements that had been needed to render in high definition.”

The demo was running at 25-45 frames per second and was basically in the same detail level as the full screen demo shown last year.

Image courtesy Intel

Intel does admit that there is still work to be done both on the hardware and software side of ray tracing development:

“Now, keep in mind that this is just the graphics engine running, and the technology still needs to develop to the point where we can run multiple rays per pixel within a sensible compute budget, because that will allow us to add the kinds of lighting effects, per-pixel correct shadows and reflections, and complex geometry that gamers expect in leading edge games.”

Intel claims that Moore’s law will help them, as you would expect, giving more power and more cores to even the lowest power form factor.  Since processing power continues to increase at a much higher rate that screen resolutions, the capability to ray trace on nearly any size screen should be a reality in the not-too-distant future. 

The real strength with this demo at the Game Developer’s Conference, as Intel sees it, is that games can be created and easily transported from form factor to form factor by utilizing the scaling ability of ray tracing:

“We believe that with Ray-Tracing, developers will have an opportunity to deliver more content in less time, because when you render things in a physically correct environment, you can achieve high levels of quality very quickly, and with an engine that is scalable from the Ultra-Mobile to the Ultra-Powerful, Ray-Tracing may become a very popular technology in the upcoming years.”

Not everyone we have spoken to in the past few months sees ray tracing in such a positive light over existing rasterization rendering techniques – but we’ll have more on that soon enough.

You can read more about Intel’s ray tracing work here: