FLIP particles missing in the middle of the scene

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Hey

I'm trying to make a river and i've created an inital flip fluid tank to fill the scene then 4 emitters at the start of the river to flow down. The inital tank was created using a cookie node to get the basic shape of where i want the fluid to be.

My issue is when i start to skin the particles using VDB. When i move the camera into the water i can see a big absence of water present in the area. When i look at this scene as particles this gap is clearly visible. There isnt any geo present in that area and am a bit lost as to why this is being caused.

A side effect of this causes the water to look VERY turbulent.

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8xmab.jpg (342.0 KB)
hfkfp.jpg (177.5 KB)

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You don't have enough particles to get smooth mesh.
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Your second image what you called gap is because you are meshing a flip tank which creates to layers one is top and another is bottom.
You need only top layer for rendering. There is many ways to delete bottom layer. You can delete by bounding object or mask vdb or activate vdb by camera and vdb box which envelop only top layer.
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When looking at the scene through a particle view, this massive gab is clearly visible and there are no particles within this area. This also seems to be happening to emitters ive set up using cubes.

The image shows the nodes im using to mesh the particles and also what it looks like when i turn smoothing off, i still get this bubbly blotchy look. I'm really lost as to whats causing this? The particle separations are at 0.03.

Also even when i'm meshing the particles surely it shouldnt have this blotchy appearance?

Attachments:
mk97f.jpg (89.4 KB)
0ba4q.jpg (20.4 KB)
rtbzc.jpg (56.5 KB)
scene water error.zip (1.4 MB)

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I can't reproduce your problems. See image in attachment.
Are you sure you added the same .hip you are having the issues with?
Because I just opened your file and what you see in my image is what I got without adjusting anything.

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RagingWater.jpg (508.6 KB)

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Firstly thanks for having a look at my issue

To reproduce the issue skip forwards a frame. The image i posted was on frame 10 the issue issue doesnt seem to be present at frame 1 as i get the exact same image when i'm on frame 1.
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As far as I can see, it was your Influence Scale and/or Particle Separation on the VDB from Particle Fluid.
I reverted Influence Scale to default (of 3) and I got what you can see in the image.
Nothing else has been changed.
So I'd say you can either do that, or create more particles to fill in the gaps.

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RagingWater_InfluenceScale.jpg (413.3 KB)

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i cant thank you enough for your help! saved me a lot of pain and crying inside. I'm still learning Houdini and was wondering how would i be able to increase the amount of particles? i reduced to particle separation and thought that would produce more particles, but i cant seem to see an option to increase birth?

Thanks!!
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You can also set a particle separation on the Fluid Source SOP under the Particles tab.
That will in crease the amount of particles to birth from.

What you could do is copy the particle separation from your fluid object and paste relative reference in the particle separation in the Fluid Source SOP.
That way, if I'm not mistaken, you will avoid setting a more detailed particle separation than you can actual take information from.

I have to be careful what I'm saying here, cause I'm far from an expert myself
- A little nonsense now and then, is relished by the wisest men.
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