Resolution dramatically changing shape of things...

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Polyguy
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Joined: Thu Jun 13, 2019 10:08 pm

Resolution dramatically changing shape of things...

Post by Polyguy » Fri Jul 26, 2019 11:32 pm

Hello again all. Client revisions are in...

I'm basically starting a lot from scratch, but I've learned a lot.

So...I've re-simulated everything. The meshed particles look the way I want at resolution 10...but when I crank up the resolution to 100, there are irregular splashes, the shape of the splash and crown are much thicker...it's ugly...

Why? Do I have to change steps after resolution change? What factor would mostly influence this? How do I keep the same thickness and stop tiny drops and splashes from occurring? Do I have to add a k-speed now for minimizing splash drops? And how do I maintain the thickness?

Thank you greatly in advance.

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ChristianZ
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Re: Resolution dramatically changing shape of things...

Post by ChristianZ » Mon Jul 29, 2019 7:42 am

Changing resolution also changes the size of individual liquid particles and the mesh is changed too. There is not really a formula or dedicated function to adapt the mesh, so experimenting with (especially) the radius will be necessary.
RF10.5 standard + RFC4D3, Mac&Windows

Polyguy
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Joined: Thu Jun 13, 2019 10:08 pm

Re: Resolution dramatically changing shape of things...

Post by Polyguy » Mon Jul 29, 2019 5:50 pm

Thank you. I'll mess around with the radius of the meshed particles.

I don't want to bombard this forum with my questions, so I'll keep all additional questions about this project HERE in this thread.

And as it were, I do have an additional question at the moment:

I have set up an initial settled state for my water base. And to minimize odd square shapes in the water I've set my scene in a cylindrical pool, however, if you notice there are irregular ripples in pool. I've got a smooth of 60 on everything, and it still occurs. I don't want to lock the water to a specific state with k-speed, because that might create issues with the crown and splash animation correct?

Will this documentation help?: http://support.nextlimit.com/display/rf ... d+Surfaces
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I'd prefer to fix this in Realflow as opposed to working on the ABC file in my 3d software.

Polyguy
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Re: Resolution dramatically changing shape of things...

Post by Polyguy » Mon Jul 29, 2019 8:05 pm

Here is an example of the resolution changes...

The image on the left:

resolution: 50
mesh poly size .005
radius: .04
surf tension: 10
viscosity: 3.3

The image on the right:
resolution: 15
mesh poly size: .01
radius: .08
surf tension: 10
viscosity: 3.3

In order to maintain detail in the higher resolution, I've had to lower the size of mesh poly and radius...if I don't it gets very blobby, however, even with increased detail, it's still too blobby, and I'm getting splatter which I don't want. I want the shape and feel of the right image, but with higher resolution and I can't get the by golly! :)

Thanks
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Polyguy
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Re: Resolution dramatically changing shape of things...

Post by Polyguy » Wed Jul 31, 2019 2:18 am

adding to the post...

I'm also very distraught how the strange ripples and deformations are occurring in the main body of the liquid.

This is a resolution of 100, same poly size and radius as the above settings...and I've locked the timeline and pre-rolled the simulation for a long time before locking it and setting the initial state...and it still produces the terrible water surface. Of course it's exaggerated in Realflow--when I place it in Blender and light it with softboxes, it is way less obvious, but it's still there.
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ChristianZ
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Re: Resolution dramatically changing shape of things...

Post by ChristianZ » Mon Aug 05, 2019 7:31 am

Hi
these layers in the mesh are indeed an unpleasant "feature" of the grid-solvers.
In the mesh type "particle mesh" you have the "smooth" parameter that can be useful for such problems, although it tends to reduce details at the edges.
In the "Particle Mesh VDB" type of mesh you have the option of filters (mesh-filters-volume filters), and those themselves can be fine-tuned again to reduce the layers. It may be useful to test the different settings only on a part of the particles in the scene for speed reasons.
RF10.5 standard + RFC4D3, Mac&Windows

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