Image: Arm

The first hardware-based ray tracing on mobile will be included in Arm's new flagship graphics card. As PCs and the latest Xbox Series X and PS5 consoles are all gradually moving towards impressive ray-traced visuals, Immortalis-G715 is designed to be the Arm's firstGPU to deliver the same.

With 10–16 cores in mind, Immortalis is designed with a boost of 15 percent over the previous generation premium graphics cards. Arm sees Immortalis as the beginning of a transition to ray tracing on mobile following its success with the 8 billion GPUs that have shipped to date

The new Immortalis GPU will have 10 cores or more.
Image: Arm

According to Andy Craigen, director of product management at Arm, the challenge is that Ray tracing techniques can use significant power, energy, and area. Ray tracing on Immortalis-G715 only uses 4 percent of the core area, while delivering more than 300 percent performance improvements. It's not clear if a 3x speedup over software-based ray tracing will be enough to entice game developers, but when Nvidia introduced hardware accelerated ray tracing in its RTX 2080, it advertised a 2x3x boost at the time. "It's the right performance point for now to get this technology into the market, and it may also come in handy in augmented reality applications where it could be used to match virtual lighting to the real-world environment around you."

The promise of hardware support means we will see flagship smartphones with this chip at the beginning of the next decade. The Exynos 2200 chip was announced earlier this year and manufacturers are getting ready for the games to arrive.

Craigen says that the partners are ready, the hardware is ready, and the developer community is about to get ready. There isn't a clear commitment from any game developers just yet, as Arm only provides a couple of examples of ray tracing on its mobile graphics cards. It will take time, but we should see some interesting experiences on mobile over the next year or so.

The Arm has an update to its main line. Variable rate shading is included to increase gaming performance and energy savings. The details in the background don't need as much rendering power as the parts of a scene that need more detail. Craigen claims that they have seen improvements of up to 40 percent on frames per second. The new Arm graphics cards will have a 15 percent improvement in energy efficiency over their predecessors. Arm wouldn't say how much more expensive the device would be.

The move by Arm to support hardware-based ray tracing on its graphics cards is significant for mobile gaming. Powerful graphics cards that are found in gaming PCs or PS5 consoles are the only ones that can be used for ray tracing. Last year, there was a demonstration of ray tracing with the help of an Arm processor. The effort is focused on PCs and likely Chromebooks-like laptops, but Arm's new Immortalis is focused on the operating system.

Arm shared a chunk of its roadmap, which shows that it will have a flagship "Titan" and "Krake" in the next two years. We were not told if Titan or Krake will expand ray tracing support.

The Unreal Engine is one of the things that Unreal Games is supporting. The real test of this type of support will be how many mobile game developers implement ray tracing. Arm says it will use the VulkanAPI. It is unlikely that we will see a flood of mobile games moving to ray tracing.

This is Arm's first hardware-based ray tracing chip, not an industry first according to the article.