Flickering shadows in HDRP

I checked out HDRP several months ago and remember noticing that realtime shadows behaved oddly. I didn’t think too much about it at the time, as HDRP is still in beta, and perhaps I wasn’t configuring the options optimally. However, now when I’m checking out the FPS sample project (great job on that btw), I notice the shadows still behave strangely. No matter how much I try to configure the HD Shadow settings in the volume component, there will always be very noticeable flickering at the edge of the shadows. Here’s a video:

This is not a problem in the default rendering pipeline:

Is this a known issue that will be fixed, or what’s going on?

I would like to know about this too, i get flicker a lot in volume lighting in Unity 2019.2 and latest HDRP

Please note down HDRP version numbers exactly as it really matters.

This is not flickering, it’s simply the shadows are set to lower resolution. I tweaked the settings for my game and all that went away.

But they don’t if I use default settings.

You need to start digging into HDRP volume and engine settings files and tweak it to your game’s requirements. As such I really think there is no problem here other than a failure to touch any options.

When I tried tweaking settings before, while the flickering could be reduced, it could not be entirely eliminated. Things might have changed since then, so maybe it’s better now, and atm I’m not investigating HDRP. But just out of curiosity - what settings exactly did you change? I remember playing around with shadow cascade biases and resolutions, but to no avail.

I played with all possible setting that not require coding and i still get some flickering in image effects that query depth, it is like some internal problem in the engine.

HDRP version is 5.2.3, used in Unity 2019.2.0a9

I’m surprised this even works, not only 5.2.3 is super early version of 5.x HDRP, it’s not very stable in general. You are using all possible unreleased things with a mix that’s not even officially supported. Use 6.7.1 or later for 2019.2 + your 2019.2 is really old as well, we are currently at 2019.2b7.

In general, if you want more stable experience, stick to the released Unity versions, right now this means latest 2019.1 and couple it with 5.16.1 HDRP.

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I used this one because was supposed to be the way to go to make image effects for the new pipelines, there was a tutorial about it as well.

Of course all that is changing now i guess. I hope we get a similar tutorial on how to convert our effects to the HDRP image effects soon.

I can eliminate the flickering when I disable the Static Lighting Sky component from my Scene Settings profile. Using 2019.1.9f1 and hdrp 5.16.1.

I also have strong shadow flickering, especially on the 2nd cascade, with Unity 2019.1.12f1 + HDRP 5.16.1 + Directional light + any shadow filtering in HDRenderPipelineAsset → Lighting → Shadow → Filtering Qualities.

However, it only happens when I change the camera FOV (which can be all the time in my game, depending on the camera mode chosen by the user).

It was workly flawlessly with the Built-in pipeline. :frowning:

EDIT:
raising the Directional Light’s Shadow Map Resolution from 512 to 2048 fixed the issue, and in bonus now the shadows look as good as in the Built-in pipeline…! :stuck_out_tongue:

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I have this exact issue. Turning off Shadow Maps fixes it but it ruines shadow quality. It’s only an issue for moving objects or when moving the camera.

Setting the quality to 2048 makes it marginally better but not enough.

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