Future iPhones May Offer More Realistic Lighting and Shadows with New Ray-Tracing GPU
Apple’s graphics partner for iOS devices, Imagination Technologies, has announced a new version of its PowerVR graphics architecture that includes ray-tracing capabilities. Apple currently uses the PowerVR G6430 graphics package from Imagination in its latest A7 chip that powers the iPhone 5s, iPad Air, and Retina iPad mini, so Imagination’s new technology is likely of interest to Apple.
Offering more realistic lighting and shadows, the new GPU design known as “Wizard” marks a significant leap forward by bringing ray tracing to mobile devices.
For the better part of the last eight years, we have been busy developing unique hardware and software technologies to radically lower the cost and dramatically increase the efficiency and performance of ray tracing.
This work culminates at GDC 2014 with the official launch of the PowerVR Wizard GPU family, a range of IP processors that offer high-performance ray tracing, graphics and compute in a power envelope suitable for mobile and embedded use cases. This opens up the potential of highly photorealistic, computer generated imagery to a host of new real-time applications and markets not previously possible.
Rasterization is still the fastest and most effective way to implement a number of real-time rendering steps – rasterization has been called the ultimate cheat in graphics, and over the years hardware and software developers have gotten very, very good at this cheating – so the idea is to continue to use rasterization where it makes sense, and then implementing ray tracing effects on top of scene rasterization when they are called for. The combination of the two forming a hybrid model that maintains the benefits of rasterization while including the benefits of ray tracing.
Comparison of traditional rasterized (top) and hybrid rasterized/ray-traced (bottom) scenes
Alongside the upcoming mobile GPU designs that will support ray tracing, Imagination’s expertise in ray tracing will include an impact on game developers in the nearer term with yesterday’s unveiling of version 5 of the popular Unity game engine. Unity 5 will leverage Imagination’s ray-tracing technology to allow game developers to view lighting changes in near real time, accelerating the development process.
Apple has not been explicitly mentioned as interested in taking advantage of the new Wizard GPU designs, but the company has used Imagination GPUs in all of its iOS devices and is a minority investor in Imagination, holding an approximately 10 percent stake in the company.
As for timing, it seems that Wizard GPUs will not be making their way into products until 2015, indicating that they are not candidates for the iPhone 6, which is expected to debut later this year. Future iPhone models could, however, incorporate Wizard GPUs for more realistic graphics, and it appears that Imagination is banking on this technology becoming the standard for mobile GPUs in the future.