‘Ray tracing’, a graphics technique used for decades in animated film is set, say experts, to revolutionise the quality and realism of computer game graphics over the next few years. The technique is designed to mimic how natural lighting interacts with the world. It creates effects such as shimmering, moving reflections on water, capturing the interaction between the natural ebb and flow and rippling of different water surfaces under different conditions. It can bring to life shadows of varying depth, cast by assorted light sources.
Until now, the computing power using ray tracing requires has limited its use in computer games. An animated film is a fixed series of animated images that never changes. However, a computer game is a matrix of possibilities, the combinations of which stretch into the millions. A player controlling a character can often choose between many different options in its body movements, shape and direction.
Games often take place in vast digital terrains that don’t unfold in a set order but based on how the human player decides to explore them. This means a technique that creates natural lighting effects within computer game graphics has to instantaneously process all of the variables that would have an impact – constantly generating real time changes to how light sources would interact with what is visible on screen.
That requires huge processing power which, until now, hasn’t been a practical possibility for computer games. The result is a ‘flatness’ to gaming graphics that takes away from their realism.
But the latest technology in the world means that ray tracing can now also be taken advantage of by computer games designers. New, more efficient lighting simulation techniques have helped reduce the processing power ray tracing needs and the latest chip technology has also hugely improved the amount of processing power that affordable graphics cards can pack. PC graphics cards that support ray tracing technology have come to market within the last 12 months and the technology will be used by the coming generation of gaming consoles. The impact on the realism of graphics is expected to be even more significant than a written description can capture.
Rev Lebaredian, head of simulation at chipmaker Nvidia doesn’t undersell the development when he states:
“This is the biggest advance in computer graphics in my lifetime.”
He believes it is ray tracing technology that will close soon close the gap between ‘very good’ digital simulation and digital simulation that is almost indistinguishable from reality. Ray tracing uses algorithms that calculate how light would reflect off different elements represented by animation, mimicking how photons move in real life. The developers of the game’s graphics only need to choose the direction from which light sources are entering the scene and their strength. The algorithms take over the rest.
The retail price of the latest Nvidia graphics cards able to support resource intensive ray tracing technology is current around $349 but within a year, as production is scaled, the cheapest alternatives could have dropped to as little as $149. That starts to get towards the level that would allow the tech to become a mass market standard.
It is likely that it will take 2-5 years before the first games built to make the most of ray tracing technology come to market because there needs to be enough hardware with the latest graphics cards in the hands of gamers to make them commercially viable. But games developers have an additional incentive to use the tech because the automation the ray tracing algorithms provide take on much of the manual effort that goes into creating graphics. So gamers can hopefully look forward to a graphics revolution in a shorter time than it normally takes games to catch up with hardware advancements.