Variable Rate Shading Goes Big at GDC 2019, with Microsoft Pushing an API and Developers Committing to It

Mar 18, 2019 at 02:35pm EDT

The Variable Rate Shading rendering technique was first introduced to the graphics market by NVIDIA with the RTX (Turing) architecture. Recently it was confirmed to be supported via hardware on AMD's next-generation graphics card line, too, though this is a rumor for the time being.

Today, with the Game Developers Conference 2019 underway, Microsoft revealed an API dedicated to Variable Rate Shading as well as a significant list of game developers and publishers who've agreed to add the technology to their engines and games. These include Playground Games and Turn 10 (Forza), Ubisoft, Massive Entertainment (The Division, Avatar), 343 Industries (Halo), Stardock, Io Interactive, Activision, Epic Games and Unity.

Related Story Wolfenstein Youngblood Gets First Ray Tracing Footage from Gamescom 2019; NVIDIA Adaptive Shading Explained

Variable Rate Shading allows developers to selectively reduce the shading rate in areas of the frame where it won’t affect visual quality, letting them gain extra performance in their games. This is really exciting, because extra perf means increased framerates and lower-spec’d hardware being able to run better games than ever before.

VRS also lets developers do the opposite: using an increased shading rate only in areas where it matters most, meaning even better visual quality in games.

On top of that, we designed VRS to be extremely straightforward for developers to integrate into their engines. Only a few days of dev work integrating VRS support can result in large increases in performance.

Our VRS API lets developers set the shading rate in 3 different ways:

  • Per draw
  • Within a draw by using a screenspace image
  • Or within a draw, per primitive

There are two flavors, or tiers, of hardware with VRS support. The hardware that can support per-draw VRS hardware are Tier 1. There’s also a Tier 2, the hardware that can support both per-draw and within-draw variable rate shading.

Developers won’t have to choose between techniques

We’re also introducing combiners, which allow developers to combine per-draw, screenspace image and per-primitive VRS at the same time. For example, a developer who’s using a screenspace image for foveated rendering can, using the VRS combiners, also apply per-primitive VRS to render faraway objects at lower shading rate.

According to Microsoft, VRS provided a 14% performance boost under DirectX 12 (and NVIDIA RTX hardware) when used in Civilization VI by Firaxis. Most importantly, there was no noticeable reduction in image quality. Intel is also experimenting with Variable Rate Shading technology on their prototype Gen 11 graphics architecture, so gamers won't be missing out there.

About the author: With over two decades of experience in gaming journalism, Alessio Palumbo has led the gaming vertical at Wccftech since August 2015. He started working at a young age for Italian websites like Everyeye.it, Gamestar.it, Nextgame.it, and Multiplayer.it before kickstarting the indie English-language publication Worlds Factory as its founder and Editor in Chief. In the last decade, he has coordinated the overall output of Wccftech's gaming section, managed PR relations, assigned reviews, produced daily news coverage, edited gaming content as needed, and delivered game reviews. Arguably, his trademark content is the long series of exclusive developer interviews that have been cited by Wikipedia and by the biggest news media and gaming publications. His passion for technology also makes him knowledgeable when it comes to gaming hardware and tech. His favorite genres include RPGs, MMORPGs, and action/adventure games.

Follow Wccftech on Google to get more of our news coverage in your feeds.