Unable to use Oculus Tone Mapping technique for post-process on UE5.1

[ilikemarlasinger]

Hello,

I am working on a game for Quest 2 via UE5.1.  I have to add a feature similar to infrared-vision. Initially, I followed standard post-process tutorials, but then came into following conclusion:

- For post-process to work I need to enable MobileHDR option, which will decrease performance

- Even if I accept it and enable MobileHDR, it leads to rendering issues: effect works on Quest 2, but one eye is completely black. 

In the end I decided that it is better to stick to Tone Mapping Guide: https://developer.oculus.com/documentation/unreal/unreal-tonemapping/

I am using UE VR template, and have MetaXR plugin enabled.  Vulkan is enabled there by default. Also, I execute following command: 

r.Mobile.TonemapSubpass=1

When I build apk and run it on Quest 2, nothing happens. But if I test in UE Editor Preview, the effect works and modifies the screen colors. 

These are the post-process settings that I apply to my camera (for test purposes):

FPostProcessSettings InfraredPP;

InfraredPP.SceneColorTint = FLinearColor(0.4, 0.2, 0.9);

InfraredPP.bOverride_SceneColorTint = true;

When I read the guide, it said: "This feature is only available in the Oculus fork of UE using Vulkan"

So, my question: Is this feature not yet integrated to UE5.1 main branch? Do I still need to switch to Oculus fork for it to work?

@pro_zac 

[pro_zac · Accepted solution]

Correct, the Vulkan tonemap subpass has not yet been up-streamed to Epic. We are still working with Epic to make that happen. Note that with tonemap subpass you won't need to enable MobileHDR.

Hope this info helps!

[ilikemarlasinger]

Thanks a lot for informing 🙂 

[ilikemarlasinger]

After switching to Oculus branch, I confirm that it works on Oculus Quest 2. (Though in IDE the colors of effect are degraded)

In order to switch to branch just follow instructions under "Windows": https://github.com/Oculus-VR/UnrealEngine

[pro_zac]

You can use Android Vulkan Preview to get better visual representation in editor. 

Settings > Preview Rendering Level > Android Vulkan

[ilikemarlasinger]

Hi Again, 

The post below is about official UE5.4 release, not the Oculus Fork. 

In the release logs of UE 5.4, there is following text:

• Added Vulkan custom resolve + tonemap subpass to support mobile hdr on Meta quest devices.

So, today I installed UE5.4 on my machine, and packaged an apk (without MetaXR, since there is not a supported version atm).

I tested the game with old settings on Quest 2, and tonemapping and etc. was not working.

Then I updated my settings - enabled Mobile HDR as in the screenshot below:



And I can confirm that it works after this change. 

I wanted to ask two questions:
1) Is there any threat performance-wise if we enable HDR? Or is the impact identical to what happened in the oculus fork (i.e. only simple effects such as tonemapping, vignette and etc. become enabled with small impact on performance). The color of SpaceSky changed for me after enabling this setting, so I got curious.  
2) If we enable Mobile-HDR, should we do any other changes in the project settings? 

Would appreciate your help. @pro_zac