Requirements and Configuration

A summarised guide on the hardware and software requirements for using ray-tracing within your projects. As well as ue4 configuration to enable the features to be accessed and utilised as expected.

Hardware Requirements

• A ray-tracing supported GPU is required to make use of the RTRT features in ue4.

• At the current time of writing, these GPUs are only offered by NVIDIA which include the following:

  Turing Architecture	Volta Architecture	Pascal Architecture
  Titan RTX	Titan V	Titan XP
  RTX 2080 Ti		Titan X
  RTX 2080		GTX 1080 Ti
  RTX 2070		GTX 1080
  RTX 2070		GTX 1070 Ti
  GTX 1660 Ti		GTX 1070
  GTX 1660		GTX 1060 (6GB edition)

• It should be noted that not all supported GPUs are capable of supporting the full set of RTRT features:

  RTX Products	Non-RTX Products
  High ray count	Low ray count
  Complex RTRT effects	Basic RTRT effects
  Multiple RTRT effects

Software Requirements

• A Windows operating system is required as the RTRT features make use of DirectX Raytracing (DXR). Additionally, a minimum build version of 1809 is required.

• Unreal Engine version 4.22 or later is required to access the RTRT features.

• These RTRT features then need to be enabled within the Project Settings:

  • Set the Default RHI setting to DirectX 12 in the Platforms->Windows section.

  • Enable the Ray Tracing setting in the Engine->Rendering section.

  • If the Support Compute Skincache setting is not enabled, a dialogue will appear prompting confirmation for the setting to be enabled - click Yes.

  • Restart ue4 to effect the configured settings.

Engine Changelog

• This section summarises any general ray-tracing improvements/modifications as new engine versions are made available.

• UE 4.22:

  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 (ray traced global illumination)

  • Translucency

  • Clearcoat

  • IBL

  • Sky

  • Geometry types

  • Texture LOD

  • Denoiser

  • Path tracer

• UE 4.23:

  Ray Tracing support has received many optimizations and stability improvements in addition to several important new features, including performance and stability enhancements, additional geometry and material support, and multi-bounce reflection fallback.

• UE 4.24:

  Stability and performance improvements, including support for static meshes that use vertex animation.