tech2 News StaffAug 27, 2019 15:07:24 IST
Popular PC benchmark developer UL Benchmarks has introduced a new feature to test Variable-Rate Shading (VRS) in the paid versions of its 3DMark Suite. VRS is a relatively new feature that Microsoft added to DirectX 12 to improve gaming performance.
According to Microsoft, DirectX 12 is the first graphics API that supports VRS on a broader hardware level. Without getting into too much detail, this feature gives developers more control over the distribution of a GPU's resources by allowing them to limit the visual fidelity of regions that are virtually invisible to the player. A region in heavy shadow doesn't need a lot of colour, for example. Ultimately, this will result in smoother performance in games.
Getting a little more technical, in the context of rendering with GPUs, shaders are used to calculate the colour of every pixel on the screen. The shading rate is the number of pixel shader operations being called to render each pixel. So, the higher the shading rate, the higher the accuracy of the colours of each pixel. However, this will use a lot of GPU resources. When the shading rate is lower, although the performance will be higher, it would mean lower visual fidelity. For now, developers have been setting the same shading rate for each and every pixel on the screen. It's possible to manually set a lower shading rate for certain areas, but it involves a lot of effort. Variable-rate shading largely automates this process.
The aim with VRS is to render frames that are virtually identical to a full fidelity image.
Apart from detailing the features, compatibility, and comparison of the test, UL Benchmarks also released a demo video to showcase the difference in a specific frame with VRS turned on and off.
Areas that are either dark or far from the camera can be given a lower shading rate whereas areas in focus could be given a higher shading rate to balance and use the GPU efficiently. You can read a more in-depth explanation of VRS on Microsoft’s DirectX Developer Blog.
Using the industry-standard benchmarking tool, 3DMark, Variable-Rate Shading can be tested on a Windows 10 machine running version 1903 and a DirectX 12 GPU. This includes NVIDIA’s Turing-architecture GPUs and Intel’s Ice Lake CPUs with integrated Intel Gen 11 graphics.
The VRS test will be a free update to 3DMark Advanced Edition and 3DMark Professional Edition.