PowerVR Graphics Architecture
PowerVR Furian architecture is a new architecture for embedded GPUs, the successor to the industry-leading PowerVR Rogue architecture. The new architecture brings about a large number of completely changed blocks for improved performance, power and density. It encompasses the significant improvements made to Rogue architecture throughout its life span.
PowerVR Rogue designs enable our partners to deliver amazing user experiences in devices that range from innovative, ‘natural’ user interfaces to ultra-realistic gaming, as well as enabling new applications never before thought of, from advanced content creation and image processing to sophisticated augmented reality and environment-aware solutions.
PowerVR Ray Tracing
PowerVR ray tracing graphics IP is highly scalable, making it potentially disruptive to many markets from mobile to high-end gaming and the creative arts enabling more immersive games and apps with real-life dynamic lighting models that produce advanced lighting effects, dynamic soft shadows, and life-like reflections and transparencies.
Tile Based Deferred Rendering (TBDR) architecture
The PowerVR architecture splits the screen into a number of ‘tiles’, which are then processed individually (in parallel to other tiles). Since the GPU only needs to work on a subset of the complete scene data at any given time, this data (such as colour and depth buffers) is small enough to be stored in internal GPU memory, significantly reducing the required number of accesses to system level memory. This results in lower energy and bandwidth consumption and also higher performance.
PowerVR deferred rendering uses a unique, patented method of Hidden Surface Removal which defers all texturing and shading operations until the visibility of each pixel in the tile is known – only the pixels that will actually be seen by the end user consume processing resources. This means that unnecessary processing of hidden pixels is eliminated, which further ensures the lowest possible bandwidth usage and number of processing cycles per frame, resulting in the highest performance levels and the lowest power consumption.
The PowerVR ray tracing graphics architecture enables more immersive games and apps with real-life dynamic lighting models that produce advanced lighting effects, dynamic soft shadows, and life-like reflections and transparencies, previously unachievable in an efficient real-time device.
PowerVR ray tracing is highly scalable, making it potentially disruptive to many markets from mobile to high-end gaming and the creative arts.
High-performance, highly flexible microkernel
All PowerVR GPUs are managed by firmware which controls all higher-level GPU events. This approach offers numerous advantages including full offloading of virtually all interrupt handling from the main host CPU while maintaining maximum flexibility.
PowerVR GPUs feature a dedicated multi-threaded microcontroller to run the microkernel, which allows full debugging functionality of the GPU. The software-based management of the GPU ensures the ability to adapt to future market requirements as well as providing optimal performance through priority-based execution of GPU tasks. The microkernel also has the ability to help SoC designers implement advanced power management features by, for example, signalling workload information to DVFS and power-gating logic within the SoC.
Virtualization and Security
GPU virtualization is now a must-have for a range of next-generation applications, from automotive, to consumer electronics, to the IoT. GPUs that implement hardware virtualization can provide isolation between the various applications/OSs for increased security, as well as maximum utilisation of the underlying GPU hardware. PowerVR GPUs, from Series6XT onwards, support hardware virtualization and in Series8XT its capabilities have been further enhanced.
PowerVR GPUs feature PVR3C Triple Compression, a suite of three compression technologies to ensure the most efficient use of memory bandwidth. Image compression (PVRIC), texture compression (PVRTC, ASTC) and geometry compression (PVRGC) can significantly reduce system-level memory accesses required by the GPU. Benefits of reduced memory bandwidth consumption include lower power consumption, better overall system efficiency and reduced system-level memory costs.
For the first time in the industry, PVRIC4 delivers the benefits of visually lossless image compression. It is a highly efficient compression scheme that dramatically reduces memory accesses, automatically compressing data before it is written out of the GPU and decompressing it as it is read back in from memory.
Available in future PowerVR GPUs, PVRIC4 implements a dual-pipeline architecture that simultaneously passes data through lossless and visually lossless compression pipelines and automatically chooses between them to deliver a guaranteed minimum 50% reduction in memory footprint and at least a 50% reduction in system bandwidth. This enables SoC manufactures to reduce costs and optimise power consumption.
For further bandwidth savings, the PVRIC4 decompression logic can be integrated into the SoC-level display pipeline, which then allows the GPU to also compress the final frame buffer image before it is written to memory, with a guaranteed compression ratio of 2:1. PVRIC compression is the only image compression scheme which works with block-based memory access patterns of a video decoder to enable high-efficiency system-wide image compression.
Enabling the compression of textures can significantly reduce application file size and download times; it also dramatically improves runtime performance and power consumption by keeping bandwidth usage to an absolute minimum. PowerVR GPUs provide support for a number of industry-standard texture compression formats.
The highly-acclaimed PVRTC lossy texture compression format is one of the most widely used texture compression formats in the mobile industry today, having been implemented in over a billion devices. It is fully accelerated in hardware on all PowerVR SGX and PowerVR GPUs. PVRTC enables both RGB and RGBA formats to be compressed into 2 or 4 bits per pixel versus the standard 32 bits formats, resulting in compression ratios from 8:1 up to 16:1.
PVRTC2 is a major upgrade and builds on the many strengths of PVRTC, adding a wide range of additional features including:
- Improved image quality, especially for textures with high contrast, large areas of significant colour discontinuity, or boundaries of non-tiling textures
- Better support for pre-multiplied textures
- Support for arbitrary sized NPOT (Non Power Of Two) textures
ASTC* is an efficient texture compression technology which allows encoding of a wide variety of texture formats at bit-rates ranging from 8 bits per pixel to <1 bit per pixel. ASTC was developed under the cooperative process at Khronos and supports monochrome, luminance-alpha, RGB and RGBA formats, as well as X+Y and XY+Z formats for surface normals, and provides the flexibility for any format to be encoded at any bit rate. Uniquely, the encoding method is chosen independently for each block of pixels in the image, so that the coding adapts dynamically to most efficiently represent the image region-by-region.
PVRGC Geometry Compression*
To help manage the increasing geometry complexity of 3D scenes, PowerVR GPUs can include PVRGC (PowerVR Geometry Compression) . PVRGC minimises memory usage by automatically compressing the intermediate geometry parameter data that is written to memory as part of the tiling process. The data is then automatically decompressed as it is read back into the GPU later in the pipeline, resulting in a significant reduction in the required memory bandwidth.
* Support is optional on some variants
News from Imagination
It can be tough trying to figure out the best way to optimise your applications for the hardware during development. Luckily, we’re here to help and – this is the first of an ongoing series of blog posts highlighting useful tips and tricks from our brand-new documentation website.
Recently, our Developer Technology Lead Support Engineer, Marton Tamas, presented at Digital Dragons 2019 in Krakow, Poland. Watch the video here!
Imagination to unveil innovative approaches for low-power devices at the Linley Fall Processor conference 2018
The Linley Processor Conference features technical presentations that address the latest developments in communications, IoT, servers, and advanced automotive systems. It takes place twice a year and the next one is taking place on October 31 – November 1, 2018,
Back in May, we were proud to announce Furian; the first new graphics architecture from PowerVR since Rogue. A mainstay of the GPU market since its introduction in 2012, Rogue-based designs continue to be performance and power-efficiency leaders across a