Wake / foam artifacts when moving the camera quickly about crest

[daleeidd]

Thanks. I was able to reproduce the issue. It is related to camera movement and not rotation. You need to move back and forth at an angle. The artefact is directional so depending on angle will determine the nature of it. Likely an artefact at the LOD transition. I will look into it.

[daleeidd]

Fixed for next release. This was streaking due to clamped texture sampling. The previous anti-streaking measure was not effective enough so implemented something more solid.

Thank you for the detailed report.

[daleeidd]

Thanks. I was able to reproduce. I just needed to move faster.

[daleeidd]

Alrighty. I reverted the previous fix made for 4.18 as this introduced reflections at the LOD borders as you saw. Instead I have feathered the dynamic wave inputs to reduce streaking.

LMKWYT. Be aware though there will be some streaking/reflections as it is not possible to eliminate both as far as I can see. What we're looking for is an improvement overall.

New branch: fix-dynamic-waves-edge-reflections.

[daleeidd]

Thanks!

[Revmatek]

@daleeidd

I patched from the commit that fixed this and played around with it for a while, it seems to have fixed the initial streaking problem. I am noticing some very similar streaking when zooming in and / out when rotating the camera as the LODs change. I am not positive it is from this change or if it is the same problem but it is worth looking at. If you want me to make a new issue for this that is fine.

Its very easy to see in latest if you set the Wake10m size to max (40) and move the camera out of the WakeRig and increase the speed, then zoom in and out to the point where the foam is not visible

For reference:

Streaking in latest:

Seen in game when zooming in and out while moving the camera:

It seems like as the wakes generate they start to form streaks near the edges of the tiles. Once this starts to happen you can zoom in and out or move the camera in general and it will start to magnify the issue:

Seems to happen whenever foam appears and changes when the camera moves in various ways (spinning boat in circles here to create foam constantly):

One more key piece of info, the foam fade rate. It very hard to see at 0.1, I think I have mine set to 0.5, I set it to 1 in the BoatWakeScene and was able to get very similar behavior to what I see in game:

This was produce by observing the streak and zooming in and out

[daleeidd]

Thanks. Looks like it is a problem with Dynamic Waves rather than foam. I struggled to reproduce it. But I have a potential fix if you're willing to test it? fix-dynamic-waves-edge-artefacts

[Revmatek]

Thanks. Looks like it is a problem with Dynamic Waves rather than foam. I struggled to reproduce it. But I have a potential fix if you're willing to test it? fix-dynamic-waves-edge-artefacts

Yes, I will take a look shortly.

[Revmatek]

Thanks. Looks like it is a problem with Dynamic Waves rather than foam. I struggled to reproduce it. But I have a potential fix if you're willing to test it? fix-dynamic-waves-edge-artefacts

Yes, I will take a look shortly.

I do still see the problem with these changes:

I am able to reproduce this in latest with the following steps:

1. Open "BoatWakes" scene
2. Set the "Foam Fade Rate" to 0 on the ocean renderer
3. Move the DemoCamera to the root of the scene so that it is no longer moving with the WakeRig
4. Zoom out:

5. Zoom in to random portions of the wake

6. Repeat 4-5 and move / rotated the camera until you start to see corner like wakes appearing
7. Once you see the corner like wake, zoom in and out on it very slightly close up to see the corner become more defined / streaked

Stats if helpful:

This last one I tried with the patch on latest just to make sure:

[Revmatek]

Here are some video steps, hard to describe.

repro1.mp4

It seems easier to see with the wave spectrum zeroed out:

repro2.mp4

[Revmatek]

Alrighty. I reverted the previous fix made for 4.18 as this introduced reflections at the LOD borders as you saw. Instead I have feathered the dynamic wave inputs to reduce streaking.

LMKWYT. Be aware though there will be some streaking/reflections as it is not possible to eliminate both as far as I can see. What we're looking for is an improvement overall.

New branch: fix-dynamic-waves-edge-reflections.

I think this looks great! Definitely an overall improvement. I don't see any streaking with normal camera movement / rotating. Corner issue is gone. I did see a very minor streak when impacting the water with a plane (creating a large deformation) and rotating the camera at the same time but I can live with that. I will keep an eye out for similar artifacts in the future and let you know, but this seems good to me.