Who is Caustic Graphics?
Ray tracing. Many have said that graphics rendering by ray tracing is the only way to truly achieve the imagery end-game we all seek. Many have disagreed. PC Perspective has been here covering both sides of this debate for quite some time.
We have hosted articles from ray tracing visionaries
; we have interviewed prominent game developers
and tech minds
on the topic; we have seen what ray tracing developers envision
; we have looked at Intel’s team
of minds on ray tracing; and now we investigate another claim on the path of ray tracing's move to the mainstream.
In the past, and even today, there is a lot of discussion on the ability to solve ray tracing with current generation hardware and with mainstream existing algorithms. Most of the current ray tracing implementations are based on the idea of “packet tracing” where blocks of pixels are grouped together to trace a set of rays that start out adjacent to each other. That will definitely increase efficiency of ray tracing for the first bounce or so but as the number of bounces increases and the randomness returns, the packets aren’t able to “stay together” in terms of their memory locality. Even with advancements in shader processor development to include inter-thread communication (DX9 required this move) modern GPUs do not have enough bandwidth to handle the data shuffling required for RTRT (real-time ray tracing) processing, at least according to Caustic.
In most cases for rasterization, pixels are completely independent of each other but in ray tracing that is not the case – with many rays being traced inside each pixel they becoming massively DEpendent.
Caustic Graphics finds the answer
James was quick to iterate to me on a few occasions that they initially had no desire to build hardware but as they developed their unique software algorithms it became apparent that there simply was not a processor on the market today, either in GPU or CPU form, that did exactly what they needed. These new algorithms attempt to find order in what we all see as the randomness of ray tracing and they attempt to drastically increase the memory locality for efficiency reasons and the founders decided that required a custom co-processor. But they seem to have played the game intelligently by continuing to utilize hardware where it is most efficient: the Caustic card will handle only the operations that modern components are inefficient at yet they still leverage the power of the GPU for pure shading horsepower.
The CausticOne only uses standard DDR2 SO-DIMM memory
An analogy that quickly crops up when discussing Caustic is another add-in accelerator start up from a few years back: AGEIA. In that case a new company wanted to sell a hardware and software solution to accelerate a technology for gaming purposes though the idea has never really taken off since the install base for the AGEIA PhysX hardware was always so low. Now that NVIDIA has acquired the company and ported the software to GeForce GPUs there is a larger, but still small, collection of titles that implement the standard. For the desktop market, Caustic’s offering is very similar and has the same problem: game developers might want to add ray tracing-only features to their games that require the speed and acceleration of the Caustic card and thus an incredibly small market. More than likely this means that for the immediate future of Caustic Graphics, the desktop market will be untouchable.
Future of gaming?
The one advantage that Caustic has over a company like AGEIA is a second, much more profitable market to sell to: professional and enterprise users. While gaming is the most immediately visible target for this type of technology from a consumer’s point of view, the move away from rasterization on the PC and console world would be too dramatic a shift to have happen in my opinion. But there are a whole host of media and entertainment designers, product designers, architects and more that already using ray tracing on a daily basis, know and understand the benefits of ray tracing to their work and would likely see great productivity enhancements from the CausticRT platform.
Real-time demo with AA enabled
Real time Demo Video: Link