Ocean surface extended mesh broken with holes

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I am using a guided ocean layer shelf setup.

It appears something is occurring on the fluid extension aspect.

The incoming cached fluid looks fine.


But at the point when that is getting particlefluidsurface somehow it's breaking.



On inspection the particlefluidsurface appears to be missing the entire mesh on some frames and then when it extends those edges it appears really broken.



The cached fluid that it's using via an objectmerge node doesn't appear to have this problem. So I'm not sure how to resolve it.

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Screenshot 2023-01-12 023602.jpg (348.5 KB)
Screenshot 2023-01-12 023551.jpg (261.3 KB)
Screenshot 2023-01-12 023615.jpg (343.3 KB)
Screenshot 2023-01-12 023622.jpg (297.2 KB)

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Looks like some broken data.

- Try exporting another FLIP sim, just a handful of frames and see if it is still broken.
- check the surface field (you can visualize it inside the particle fluid surface SOP Output > Surface VDB) does it look OK?
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Phlok
Looks like some broken data.

- Try exporting another FLIP sim, just a handful of frames and see if it is still broken.
- check the surface field (you can visualize it inside the particle fluid surface SOP Output > Surface VDB) does it look OK?

Thanks for the response.

I re-simmed everything with the same result. Visualizing with a surface VDB appears like everythings filled in correctly.

On playing with this further I think I found the issue, or at least a way to kind of resolve it. It was a mismatch between bounding boxes somehow. (I'm still new to houdini.)

Essentially the defaults that come off the shelf were not working.

Whatever is going on with the bounding box to cut off the sim to create this into a flat plane were grabbing thin edges at the bottom of the bounding box and extruding them along their axis like it was doing to extend the ocean surface. And the holes in the bounding box were changing every other frame which led to huge planes not parallel to the ocean surface appearing and shifting every frame.

So for now I deleted whatever expression the y bounding box value was and reduce it until it clipped those stray edges out.

It's still not clear to me why this was happening, and still the first frame of the sim has holes in it and is acting wierd which I can't figure out. But I think it's workable now.

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Screenshot 2023-01-12 165812.jpg (977.5 KB)

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Lucas Ridley
Essentially the defaults that come off the shelf were not working.

Maybe this was intentionally included in order to provide a faster preview while tweaking, no?
Interested in character concepts, modeling, rigging, and animation. Related tool dev with Py and VEX.
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Unfortunately, the problem persists.

Changing the pad bounds fixes on one frame but introduces it on another. I can't figure out why this is happening or how to solve it.

Here's one pad bound value and then tweaking it




Then here's the same pad value between 2 different frames. The issue just pops in and out of existence on different frames even with different pad bounds.

Attachments:
Screenshot 2023-01-12 232136.jpg (233.7 KB)
Screenshot 2023-01-12 232641.jpg (797.6 KB)
Screenshot 2023-01-12 233335.jpg (774.7 KB)
Screenshot 2023-01-12 233355.jpg (771.8 KB)

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I have had this issue everytime I have used this tool and find it absolutely mind blowing that this has not been resolved in years.
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jaspergar5da7395b446a467c
I have had this issue every time I have used this tool and find it absolutely mind blowing that this has not been resolved in years.
I am struggling with this right now. Funnily enough it does not happen when you set extrusion mode to planar. But that cause massive problems during frustrum limited dicing.
I seem to have a clean version now by changing the pad bounds "expressione from ch("particlesep") * ch("voxelsize") * 40" to "* 80", doubling it. I also had an extrude division of 100 and changed to 20 (extrude distance 512) and that seemed to have helped as well.
But I'm not sure if it is clean by mere coincidence now, since I don't know the cause. And neither does anybody else it would seem.

This issue has cost me two whole days now. There is no point in using amazing tools if one ends up losing time instead of saving.
Pleas SideFX, look into it.
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OneBigTree
jaspergar5da7395b446a467c
I have had this issue every time I have used this tool and find it absolutely mind blowing that this has not been resolved in years.
I am struggling with this right now. Funnily enough it does not happen when you set extrusion mode to planar. But that cause massive problems during frustrum limited dicing.
I seem to have a clean version now by changing the pad bounds "expressione from ch("particlesep") * ch("voxelsize") * 40" to "* 80", doubling it. I also had an extrude division of 100 and changed to 20 (extrude distance 512) and that seemed to have helped as well.
But I'm not sure if it is clean by mere coincidence now, since I don't know the cause. And neither does anybody else it would seem.

This issue has cost me two whole days now. There is no point in using amazing tools if one ends up losing time instead of saving.
Pleas SideFX, look into it.

Did you RFE that?
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Hey just chiming in to see if anyone has found a recent fix for this issue. I seem to be encountering a similar problem where the extend mesh generated by the particle fluid surface node is showing artifacts at render time.

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Screenshot 2024-09-22 092318.png (1.0 MB)

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