Linear color space is extremely dark on device (Pixel XL)

[ichabodcole]

Is there any known issue with using linear color on daydream / unity?
Everything looks good in the editor, but when I test the device build everything is rendering much much darker. If I switch back to gamma everything renders as expected. Note, I'm using the internal unity renderer, not the daydream renderer / Enlighten (have not tested if the issue persists with the daydream renderer yet).

Specs:
OSX
Unity 2017.1
GVR 1.70
Pixel XL

Note, I found a bug report for what appears to be the same issue I am experiencing in the Unity tracker. I reached out in the forums and was told the bug was closed because it was a driver issue. https://issuetracker.unity3d.com/issues/android-linear-color-space-causes-darker-scene-rendering-than-expected.

[tedruxpin]

Hello ichabodcole, we have filed a bug to look into this further, thank you for bringing this to our attention.

[ichabodcole]

👍 Thanks!

[fredsa]

Linear color buffers are currently unsupported.

[GridWanderer]

Definitely interested in linear color support.

With the Unity Lightweight Render Pipeline now supporting Linear color space and also Daydream single pass for stereo rendering, definitely eager to implement linear color space next.

Is upgrading frame buffers to support linear color space something that could be considered for development?

[rusmaxham]

We're still waiting on driver support from the GPU vendors.

[GridWanderer]

Thanks @rusmaxham - we're extremely grateful for your fast response. ( =

We really badly want Daydream to succeed as the platform of choice, but are literally deciding right now whether to cancel our game's daydream release entirely (we had intended Daydream as our launch platform). There is a really noticeable difference in quality when rendering in gamma/sRGB color space.

I've been looking into any work-arounds we can do, and came upon this article from Unity from 2016:
https://blogs.unity3d.com/2016/12/07/linear-rendering-support-on-android-and-ios/

Given the support for linear color space on Android, we are wondering if we couldn't try to tackle the problem ourselves. Would you or anyone else be able to provide our team with the exact specifics of the problems your team is encountering surrounding GPU driver support?

Thanks @rusmaxham !

[rusmaxham]

Unfortunately, the issue is more complicated than if the Android platform supports linear colorspace. With VR, the Unity app isn't rendering directly to the screen where it would be able to configure linear colorspace mode directly on the framebuffer it allocated itself. Instead, Unity is given a framebuffer allocated by VR Services (out of process in some circumstances) that is under different, driver-limiting constraints that prevent the configuration of linear color space mode.