Arm today announced its new flagship GPU, called Immortalis, capable of hardware-based ray tracing for mobile devices. PCs and game consoles have had the hardware to be capable of ray tracing for a few years and now we may soon see phones, tablets and ARM-based PCs capable of it too.
Born of the Mali heritage, GPU’s that are used by MediaTek and Samsung devices, the new Immortalis GPU is made up of 10-16 cores with a 15 percent performance boost over its predecessor.
|Anti-aliasing||4x MSAA8x MSAA16x MSAA||4x Multi-Sampling Anti-Aliasing (MSAA) with minimal performance drop|
|API support||OpenGL® ES 1.1, 2.0, 3.1, 3.2Vulkan 1.1, 1.2, 1.3OpenCL™ 1.1, 1.2, 2.0 Full profile||Full support for next-generation and legacy 2D/3D graphics applications|
|Bus interface||AMBA®4 ACE, ACE-LITE, and AXI||Compatible with a wide range of bus interconnect and peripheral IP|
|L2 cache||Configurable 512KB – 2MB||2 or 4 slices of 256K, 512K or 1024K|
|Scalability||10 to 16 cores||Configurable from 10 to 16 cores delivering advanced GPU performance capabilities.|
|Adaptive Scalable Texture Compression (ASTC)||Low Dynamic Range (LDR) and High Dynamic Range (HDR). Supports both 2D and 3D images.||ASTC offers several advantages over existing texture compression schemes by improving image quality, reducing memory bandwidth and thus energy use|
|Arm Frame Buffer Compression (AFBC)||Version 1.3.24×4 pixel block size||AFBC is a lossless image compression format that provides random access to pixel data to a 4×4 pixel block granularity. It is employed to reduce memory bandwidth both internally within the GPU and externally throughout the SoC|
|Arm Fixed Rate Compression (AFRC)||Version 1.04×4 pixel block size||AFRC is a lossy image compression format. AFRC can be used for compressing external texture inputs and framebuffer outputs from the GPU. Configurable compression ratio provides guaranteed bandwidth reduction for such surfaces and memory footprint saving.|
|Ray Tracing||Yes||Ray Tracing is a computer graphics technique that generates realistic lighting and shadows by modelling the paths that individual light rays take around a scene.|
|Variable Rate Shading||Pipeline, primitive and attachment shading ratesUp to 4×4 shading rate||Variable Rate Shading decouples fragment shading frequency from rasterization frequency, providing the opportunity to make energy savings while maintaining perceived visual quality.|
“The challenge is that Ray Tracing techniques can use significant power, energy, and area across the mobile system-on-a-chip (SoC),” explains Andy Craigen, director of product management for Arm. “However, Ray Tracing on Immortalis-G715 only uses 4 percent of the shader core area, while delivering more than 300 percent performance improvements through the hardware acceleration. It’s the right performance point for now to get this technology into the market,” says Arm’s Paul Williamson, adding that it may also come in handy in augmented reality applications where RT could be used to match virtual lighting to the real-world environment around you.
“We decided to introduce hardware-based Ray Tracing support now on Immortalis-G715 because our partners are ready, the hardware is ready, and the developer ecosystem is (about to get) ready,” said Craigen. Arm provided only a couple of examples of ray tracing on its mobile GPUs today, unfortunately there’s no clear commitment from any game developers just yet. “We believe this technology has a strong place, but it’ll take time,” says Williamson, hinting that we should see “some interesting experiences on mobile over the next year or so.”