[Jim Scott]

The simplest method I can think of is to use a cloner object, or an instance (Create > Modeling > Instance). Any point animation you apply to the main object will then be matched by the clone or instance. If you want to be able to adjust the animation of the clone/instance separately later, that wouldn’t be possible, but adjusting the animation of the main object will always be matched by the clone/instance.

I’m a neophyte with xpresso too. So I wouldn’t be able to help you there.

Edit: Whoops. I didn’t see Brian’s response while I was writing mine.

[Jim Scott]

Kale,

Once you have cached the simulation and mesh, if “Use Cache” is enabled any changes you make (fluid resolution, cube/container sizes, crown, etc.) will have no effect because the program is using the cached simulation and meshes for playback and not looking at those changes. You will need to disable “Use Cache,” make your changes, and recache everything.

To clarify the necessary steps: To speed up the initial experimentation stages, use a low fluid resolution and disable the mesh so only the fluid simulation is running and all you see is particles. This includes setting up an initial state. When you’re happy with the simulation disable “Use Initial State,” increase the fluid resolution to your desired setting, and then play the simulation again to the point where the fluid has settled and create a new initial state. Since the particle interactions will depend on the fluid resolution, more particles will result in more interactions and it will probably take longer to settle down. Run the simulation again (still no mesh) and check that you’re still happy with the crown. Once you’re happy with the whole fluid simulation, enable the mesh (with your desired settings) and cache everything. Theoretically this last step is not necessary as the rendering process should run through all the math before rendering each frame, but I’ve found that sometimes when I skip the caching it screws up the rendering. To be safe, cache everything and then render. The rendering will be faster because all of the caching is already done.

When playing around with your original project I found that I had to delete the whole RF Scene and recreate it in order to get the project to work. Either something gets lost in the upload, or chalk it up to a bug, but when I just ran it from its original state there were no particles being created.

Lastly, don’t forget to use Realflow’s “Help” button at the bottom of their settings in order to get to the online manual.

Good luck.

[Jim Scott]

[Steve Bentley] “I wish Nvidia would start building computers instead of just video cards. If I could push the sims into a video card they would scream! I never thought we could get to a point where the render would be the quickest part.”

Hey, thanks for reminding me…

Something which I tend to forget about is that the Realflow C4D plugin has an option in its solver settings to “Use GPU,” though the manual does come with this caveat: “RealFlow’s Dyverso solver is highly optimized for CPU multi-core and many-core processors. Some GPUs, on the other hand, do not have enough computational power to outperform a 8 or 12 core processor – which is common hardware today. For this reason a GPU-based simulation can be slower than a pure CPU-based simulation.”

One of these days I’ll try to remember to run a test to see if my GPU (GTX 980 Ti) gives any improvement. Apparently only the fluid solver is GPU-accelerated (and not fluid – object collisions) so I’ll try to find a project where I can see a difference with and without using the GPU.

By the way, Steve, if you’re able and willing to divulge it, what’s the name of your company? I’d love to watch for your work just so I can say, “I know that guy.” 😉

[Jim Scott]

Thanks Steve,

Definitely give the plugin a try. I see they now have a version for Maya if that’s something that you use as well. The fact that fluid simulations are so taxing on a machine is probably the biggest reason I don’t play around with it much. I’ve got a decent but older Mac Pro, but as you know fluid sims need major horse power, and/or a render farm.

Take care.

[Jim Scott]

Hi Steve,

That’s right, Kale and I are using the RF plugin. I only play with it occasionally so I’m not well versed in it, but from what little comparison I’ve done the standalone version has several advantages including being able to float objects, something the plugin cannot do. The plugin does have basic dynamics in order to designate collision objects to direct the flow, contain the fluid, etc. I think it’s advantage is that it’s integrated into C4D so there’s no going back and forth, which is what it sounds like you were referring to. It also seems to be oriented towards motion graphics applications, fluids flying around fruit… that kind of thing, rather than the more realistic stuff that the standalone seems to cater to. And the standalone can work with lots of different programs, including Houdini as you mentioned, which is way above my knowledge level and capabilities.

From your posts I can tell that your experience and work is multiple levels above mine, as I am just a hobbyist who simply tries to help out others here when I can, hopefully passing on what little tidbits I’ve learned over the years of fooling around with C4D. And I try to leave the tougher questions to the experts like yourself.

[Jim Scott]

Some issues that I ran into (which I chalk up to bugginess of the plugin and inexperience on my part) were sometimes needing to delete and recreate the mesher object (may need to click on Build Mesh), and occasionally doing the same with the Crown daemon.

Just to recap: Work at a fluid resolution of .1 until you get the crown set-up and the creation time to your liking, and then before caching the simulation and meshes for rendering set it back to .5 (or whatever you desire). Unless you want the fluid to be initially splashing around, which results from it being released from its fill object, run the simulation until it settles down, stop the playback at that point and create an initial state. Then cache the simulation and meshes before rendering.

Good luck and have fun.

Edit: Also, to reduce the particle and polygon counts decrease the sizes of the container and fill objects so that the sides are just outside of the field of view.

[Jim Scott]

After playing with the simulation with the fluid resolution at .1 to speed things up I rendered out a test with the following steps:

1) Set render resolution to 640 x 320 (crown Creation Time set to 3.5)
2) Set fluid resolution to .5 and ran the simulation to around 45 frames to let the fluids settle
3) Created initial state
4) Cached simulation and mesh
5) rendered movie file

Note: Your textures will look different as I didn’t have access to several of the jpg texture files. Project time was increased to 230 frames to allow crown splash to complete.

https://www.dropbox.com/s/hy18msvo7cgro3p/SMH_movie.mov?dl=0

[Jim Scott]

Just to clarify:

It seems from your post that you might be assuming that the crown splash is triggered by the falling objects. The crown splash is triggered by its Creation Time setting – the point in time, measured in seconds – not by a collision.

[Jim Scott]

Hi Kale,

I’ve been looking at your file and in order to get any kind of reasonable simulation times I reduced the fluid resolution to .1 and shrunk the fluid containers just to reduce the particle and mesh polygon counts.

One thing I noticed was that if you want your crown to appear when the objects hit the fluid you need to change the Creation Time to around 3.5 (the objects hit at around 105 frames, which would be 3.5 seconds).

I notice a lot of bugginess with Realflow, including having the crown just stop working and having to delete and recreate it, which sounds like one of the issues you were having as well. The bugginess may also be a factor in why your simulation wasn’t working right, especially with the high number of particles and polygons you were working with. I would suggest lowering the resolution of the fluid until you get the simulation working the way you like, and then increasing it for the final rendering.

I’ll keep playing with it and see if I can offer any better advice, but as I said before I only very occasionally use this plugin and so am relearning it each time I do.

[Jim Scott]

I’m looking at it now.