Virtual Reality in the High Definition Render Pipeline

To use Virtual Reality (VR) in the High Definition Render Pipeline (HDRP), you must enable VR in your Unity Project. To do this, see the VR tab in the Render Pipeline Wizard.

Please refer to Unity XR documentation for more information about XR developement with Unity.

HDRP has been designed to fully support Single-Pass Instanced mode. This mode gives you the best performance on all platforms. HDRP also supports multi-pass but this is slower on the CPU and some features, like Auto-Exposure, can cause issues. If you encounter a problem with a specific feature, you can disable it in your Project’s HDRP Asset.

You can also watch the presentation from Unite Copenhagen (October 2019) to learn more tips: Maximizing visual fidelity in VR: HDRP support

Supported Platforms and Devices

  • PC with DX11:
    • Oculus Rift & Rift S (Oculus XR Plugin, Windows 10, DirectX 11)
    • Windows Mixed Reality (Windows XR Plugin, Windows 10, DirectX 11)
  • PS4:
    • PlayStationVR
    • Open VR*

Note: Valve is currently developing their OpenVR Unity XR plugin for 2019.3 and beyond. For more information, see Unity XR platform updates on the Unity blog, and XR Plugin Architecture in the Unity Manual. The XR Plugin architecture links to the OpenVR desktop package and has further info and recommendations.

Resolution Control

There are multiple methods that you can use to control the resolution of your render targets in HDRP, but be aware that HDRP does not support every method available in standard Unity using the built-in render pipeline. XRSettings.renderViewportScale has no effect in HDRP and generates a warning if you use it. Use one of the following methods instead:

  • Dynamic Resolution: You can use the dynamic resolution system to change the resolution at runtime. This is the best method to use if you want to change the resolution at runtime.
  • Eye Texture: You can set the device back-buffer resolution by changing XRSettings.eyeTextureResolutionScale. This is a resource intensive operation that reallocates all render targets.

Be aware that SteamVR will apply a default 150% supersampling value. You can change this value in the settings of SteamVR.

Enable VR single-pass after startup

Due to some technical limitations that will be resolved in later versions, you need the following code in your script if your app does not boot directly in VR mode:

private void Awake()
{
    UnityEngine.Rendering.TextureXR.maxViews = 2;
}

C# defines

You can use the following defines to include or exclude code from your scripts.