Epic unleashes Microsoft DirectX Raytracing in Unreal Engine

The hugely popular game engine adds DirectX Raytracing support to its 4.22 release

ray tracing UE

March 22, 2019 Epic has announced that real-time ray tracing will go live in Unreal Engine 4.22 on March 26

Epic Games has announced the latest version of the hugely popular Unreal Engine will soon ship with real-time ray tracing and path tracing support. With both high-level and low-level support, the DirectX Raytracing API is being utilised as part of the UE DirectX 12 application.

That allows developers using the Unreal Engine with a DX12 focus to have access to new ray tracing effects, such as the type of reflections DICE has used in Battlefield V’s Frostbite Engine and the impressive lighting techniques 4A Games has dropped into its 4A Engine with the new Metro Exodus.

There’s only a handful of titles actually using real-time ray tracing at the moment, and one of Nvidia’s Turing-based RTX cards is preferred (support for non-RTX cards is incoming). But with such a universally used game engine offering support there could be far more titles launching with super-shiny lighting effects in the future.

Which will be a huge boon for Nvidia and Microsoft as their real-time ray tracing initiative has had a bit of a rocky birth, with somewhat inevitable complications causing problems as it was ripped from its makers’ collective womb. Urgh. A collective womb. This analogy has rather rapidly gone off the rails… I’m backing away.

Whatever, it’s fair to say that having only a few games with ray tracing support in them, some six months after the launch of the RTX 2080 and RTX 2080 Ti, wasn’t the brave new, ray traced world we were promised back at Gamescom.

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But, with Epic Games taking a genuine interest and adding it into the Unreal Engine, one of the most popular third party game engines of all time, there is genuine hope on the horizon for Nvidia’s RTX and Microsoft’s DXR technologies. This sort of support could be a real shot in the arm for both now that it is advancing out of the preview stage and into the full UE build.

The details Epic gives in the UE 4.22 notes are as follows:

Real-Time Ray Tracing and Path Tracing

Added ray tracing low level support:

  • Implemented a low level layer on top of UE DirectX 12 that provides support for DXR and allows creating and using ray tracing shaders (ray generation shaders, hit shaders, etc) to add ray tracing effects.

Added high-level ray tracing features:

  • Rect area lights
  • Soft shadows
  • Reflections
  • Reflected shadows
  • Ambient occlusion
  • RTGI (real time global illumination)
  • Translucency
  • Clearcoat
  • IBL
  • Sky
  • Geometry types
    Triangle meshes:

    Skeletal (Morph targets & Skin cache)
    Niagara particles support
  • Texture LOD
  • Denoiser
    Shadows, Reflections, AO
  • Path Tracert
  • Unbiased, full GI path tracer for making ground truth reference renders inside UE4.

Epic has also release a new UE ray tracing demo at GDC, Troll, which you can watch below.

Just giving more developers the chance to play with the different ray tracing techniques, whether or not they’re going to introduce them into the games they’re working on right now, will breed a growing pool of coders with experience of what ray tracing can actually do. Epic, Microsoft, and Nvidia are offering developers a chance to win RTX Titan graphics cards by showing off their ray tracing skills in the Unreal Engine, too.

And that could make a huge difference in how quickly, and how widely, DXR-based ray tracing effects are adopted. Which is rather exciting.