Showcase Fast Post-Processing for VR / Unity URP

In case anyone is interested and trying to solve the same problems, I wanted to share a blog post I wrote about how I implemented tonemapping and color grading in The Last Clockwinder.

The standard Unity URP post processing pipeline is written to use a secondary fullscreen pass, but instead, I made several modifications to move much of the post processing into the Forward Geometry Pass, along with the pixel shader.

https://johnaustin.io/articles/2022/fast-post-processing-on-the-oculus-quest

You can take a look at the final code in the PR here:
https://github.com/AStrangerGravity/Graphics/pull/3

The shader modifications weren't tricky, but it took some work to make the SRP Pipeline support it as an extra mode. Our fork adds an extra dropdown in the pipeline settings to enable forward pass color transformations.

Happy to answer any questions!

 

What else is in this repo?
And is spacewarp supported?

 

This is our fork of the Unity/Graphics repo. We implemented a bunch of customizations for The Last Clockwinder, which you can peek at in the PR list.
- Forward Pass Post Processing
- Baked Specular Lighting
- Disabled Directional Light and Point Lights
- A custom Fade-to-Black global shader parameter that fades all shaders to black
- Alpha to Coverage for Alpha Cutout shaders
- Various shader optimizations that are hyper specific to TLC
- (Prototype) Custom Post Processing per Render Layer

Lastly, yes! There is an Application Spacewarp implementation on this unmerged branch:
https://github.com/AStrangerGravity/Graphics/tree/asg/john/spacewarp

We didn't ship with ASW though, because it had too many artifacts in our use case.

Note that this URP fork is fairly specific to The Last Clockwinder, and so you would probably want to cherry pick changes out of it, rather than using this fork wholesale. It's not intended to be a general pipeline for all projects.

 

Hi, I find this package on asset store: https://assetstore.unity.com/packag...g-color-correction-lut-blur-bloom-urp--129638
but can't apply for urp on vr meta quest headset, have anything for help me please ?

 

Contact the developer of that asset (or at the very least make a new thread, your question has nothing to do with this thread).

 

Just wanted to say I played through The Last Clockwinder recently on quest 3 and was impressed at how smooth the experience was..... and came across this thread and another thread: https://forum.unity.com/threads/urp...rocessing-for-oculus-quest-or-mobile.1043182/

It's an interesting topic for sure! Getting the quest to run smoothly involves moving all the postfx into the forward pass. This runs fast and works well with MSAA. I only tried the BiRP version but maybe I'll check out that fork with ASW! What kind of artifacts should I look out for there?

 

Thanks for the kind words! We worked hard to get all of those clones rendering at 72fps! (It maxes out at 25 clones, but few people get there).

Good link! A major difference with our version is that we use the standard Post Processing and volume workflows, and support shader graph. We use this in a few points in the game to adjust color grading / exposure on the fly. On the other hand, their drop-in shader would be much easier to integrate.

The artifacts were with ASW itself. ASW can't interpolate information that doesn't exist. For example, if you quickly turn an object over in your hand it has to guess what the other side might look like. It's similar when you reveal objects from behind others or with fast moving objects. It was very playable, but enough artifacts that I didn't feel comfortable pushing it to players. And we had just enough performance to meet out targets for shipping.