How To: Game Development Best Practices for Quest 3 using Unreal Engine 5

Development Platform & Builds XR Development
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Best Installation Path

  • Use latest Oculus Fork of Unreal Engine 5 (https://github.com/Oculus-VR/UnrealEngine)
    • Installation instructions: Unreal Engine 5.4.x for Meta Quest VR | Community tutorial
    • Contains the MetaXR & MetaXRPlatform plugins built-in
    • Many fixes specific to Meta Quest development that the official Epic build will not have
    • Includes many template VR projects to help you better understand working with Quest 3 in Unreal Engine
    • Extra Rendering Settings not available in the official Epic build, including:
      • “Support Mobile Application Space Warp”
      • “Support XR Soft Occulsions” (for mixed reality passthrough)
    • Will be around 250GB total after you Build the Engine in Visual Studio (compared to 150GB in official UE5.4 download)

Important!

In order to correctly test Quest 3 environment on your PC in VR Preview mode, you must do the following or else you will instead have a PC VR experience when in VR Preview mode:
* Click Settings button (Top-right corner in UE5) > Preview Platform > Android Vulkan Mobile.

Rendering Facts

  • The Quest is a PowerVR tiled renderer

    • Deferred rendering would perform too poorly on it
    • Forward rendering is the only option

  • Static baked lighting is the only viable lighting option for your scene. Fully dynamic lighting is not an option.

    • Do not use movable lighting unless you add a single movable directional light (read about shadows below).
    • Use stationary lights to light your character, interactable objects, NPCs, etc. and make sure they do not overlap each other
    • Never use a rect light in your level since it is unsupported.

  • To get shadows to render:

    • Change the default shadow quality settings for Quest 3 by going to Tools > Platforms > Profiles, selecting Meta_Quest_3 and adding a Console Variable for the Rendering section, setting r.ShadowQuality to 2
    • Enable “Support Movable Directional Lights” found in Project Settings > Rendering > Mobile Shader Permutation Reduction section
    • Only use a single directional light for shadows in your level and set the directional light to movable

  • Keep draw calls as low as possible, 100 - 300

    • Combine all static meshes in a level into one mesh that uses one material and one atlas texture
    • All interactive objects / skeletal meshes should use only one material each
    • Under Project Settings > Rendering > Mobile, select “Enable GPUScene on Mobile” to improve the performance of your games by rendering the objects that share the same mesh and material multiple times, while sending them to the GPU in as little draw calls as possible

  • Keep max culled scene poly count under 100k - 200k

  • Use MSAA for anti-aliasing if you decide to use AA. FXAA & TAA will most definitely blur your scene, so do not use those methods

  • Set “Enable alpha channel support in post processing (experimental)” to “Allow through tonemapper”, which will enable the tonemapper for mobile and will fix the washed-out colors in your scene

  • Watch the following videos to understand development on the Meta Quest better

DO NOT:

  • Do not use “Stereo Foveation Level” or “Dynamic Foveation” in Project Settings > Rendering > VR. This currently crashes UE5.4.4 in VR Preview mode.

(I’ll be updating this topic as I continue working on my own project & understanding more about the nuances of Quest 3 & UE5)

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Thank you for all these tips. I’m getting back into VR dev after a couple years off, so it’s nice to see not too much has changed. One challenge I’m running into is that the r.screenPercentage console command does not work in development or shipping builds, even when other console commands do work, like stats for debugging. How are we supposed to control the rendering screen percentage to tune performance and visual fidelity these days?

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I’ll look into screen percentage for VR. So far, I know there is a project setting for Default Screen Percentages, and one of the options is for “Screen Percentage Mode for VR”, which I have set to “Manual”

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This is a great best practices list for sure. One thing I do have to mention which I have some doubts on is the “merge all actors into 1”. While it will significantly reduce draw calls etc, if done poorly and incorrectly it does not grant the opportunity to LOD any meshes at all or Cull them out. You will be rendering whichever amount of tri’s that merged mesh has become. So it highly depends on the game and meshes which I udnerstand is impossible to specifiy in a doc like this.

Imo Precomputed Visibility is quite vital to set up correctly, reducing all “Generate overlap events”, “occludes” on static meshes helps too. So only big walls and actual big blocking meshes should occlude and all smaller assets should not even be considered in that calculation.

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Thanks for starting this up. Reliable (up to date) information on this is getting harder and harder to find - to a degree i think because there is an element of “trade secrets” for the serious devs who have properly got to grips with this to not want to share too freely. The big enigma here for me is Nanite - even though not directly implemented on mobile platform, the Nanite architecture fallback system is performing optimisation steps which are not well documented in terms of how they crossover with the “traditional” VR best practices - whilst counterintuitive it seems that having nanite enabled in a mobile (EG quest) app may actually improve performance (even though it isnt actually using “Nanite” geometry) due to fallback optimisation. Id love some definitive insight into this…

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Great tips but unfortunately it seems as though until we get some kind of occlusion culling solution back into UE5 its almost certainly not worth developing for the quest 3 standalone. Unless there’s a solution to this that I’m missing?

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Actually, the UE5 Meta Fork includes the Adreno Occlusion Path, which leverages Adreno GPUs to improve occlusion culling on the Quest 3, this replaces Software Occlusion Culling i think

Performance Features UE4, UE5, Meta Plugin