Learn about controlling processor and memory usage.
- [Instructor] Let's begin by setting up the bi-frost options. Before that I just want to clean up the interface a little bit, to streamline it and make it more effective for teaching. I'm going to hide the shelf. We'll be using the menus. Go into the Windows menu and choose UI Elements, Shelf to hide it. Likewise with the toolbox over here I'm going to use the keyboard shortcuts instead. Go to Windows, UI Elements, disable the toolbox.
I am going to be using the outliner a lot. Go to Windows, Outliner. It's docked over on the left. I can minimize it by closing its tab group. Just click on the tab label Outliner. And last I'm going to hide the panel toolbar from a keyboard shortcut which is Control Shift M. Now I've got a streamlined interface for the video capture. Let's now check in on the bi-frost plug-in. Go back to the Windows menu, and choose Settings Preferences.
Plug-in Manager. Scroll down a bit, you're looking for the bi-frost section. Here it is. Bi-frost. Click Loaded in the apply to all row and also click Auto Load and that way all of the bi-frost plug-ins will load. In my version of Maya the boss ocean system was not loaded automatically. Click Close and now every time you launch Maya, all of the bi-frost plug-ins will load automatically.
Let's now look in on the bi-frost options proper. Go into the menu sets and choose FX. From the bi-frost fluids menu, go down near the bottom and choose bi-frost options. And these are very important options. In the first versions of bi-frost, these were enabled by default, but currently in Maya 2018 they are disabled by default. And that's a good thing because unless you have an extremely powerful computer you're going to want to leave these options pretty much as they are.
Let's break these options down in detail. At the top is Enable background processing, and it's off by default. If it's on, bi-frost will continue to solve when the animation timeline is not running. And this allows you to perform other tasks in Maya while bi-frost solves in the background. However there's no way to control bi-frost's CPU usage independently of other parts of Maya. It's designed to leave some CPU cycles available for other tasks, but bi-frost may use too much CPU power making it difficult to work.
So that's why Enable background processing is off. You'll only process the bi-frost simulation if you press play in the timeline. Below that we have scratch cache management. Scratch caching stores the solved simulation data in ram to allow interactive scrubbing in the timeline. If you're working on a heavy scene that requires a lot of memory to perform a solve, and or if you have limited ram in your system, then scratch caching is very likely to cause problems.
It's also probable that you'll experience problems if you try to build a disk cache with scratch caching enabled. In either case, the system may run out of memory and then start paging to disk. Swapping ram data to virtual memory on a system disk. disk paging is very bad because it will slow down the system by a factor of 10 to 1,000 and this is known as disk thrashing. Your operating system drive may fill up with virtual memory and your system may become unstable.
Under these circumstances it becomes very difficult to achieve your production goals, so I recommend leaving scratch caching disabled unless you have 64 gigabytes of memory or more. My system currently has 32 gigabytes, so to play it safe I'm going to leave scratch caching disabled. Below that is override disk location. And this is another form of virtual memory or disk paging for the bi-frost scratch cache only.
When the scratch cache needs more memory than the maximum ram usage determined here, then the scratch cache starts paging to disk independently of the operating system. This can easily result in disk thrashing or even compound disk thrashing where two different processes are paging to disk at the same time. The scratch cache is not nearly as smart as the operating system, and the scratch cache has no limits. That means the paging file may consume the entire partition.
And the default location for the scratch cache paging file is on the operating system partition. And this is the worst possible place for it to be. The operating system paging file is also on the operating system partition unless you've manually customized virtual memory. If you enable scratch caching with the default settings and try to work in a heavy scene or create a disk cache, there is a probability of your system crashing and or your operating system partition completely filling with garbage.
If your system crashes under these conditions, the bi-frost scratch cache will not clean up after itself unlike the OS which has sophisticated garbage collection. You would need to go on a search and destroy mission to reclaim your disk space and make your system function again. And it may be so bad that the computer will not even boot up normally and you need to boot into safe mode to fix the problem. So I think you're getting the idea that the scratch cache is problematic and even possibly dangerous. As a precaution, I recommend changing the over ride disk location to a separate physical disk just in case you decide to turn on scratch caching at some point.
And moving this to another partition on the same physical disk would prevent the OS partition from filling, but it would not prevent the disk thrashing and we really need to set this to a different physical disk. And I turn on override disk location, and I already know what it is in my case and it's simply on the F drive. And I've got it already created. You of course can browse to any location. So these bi-frost options are there if you have a lot of memory on a very powerful computer or if you're working on a very simple scene with not a lot going on.
But in this course I'm going to leave them disabled and will only calculate the solution when we press play in the timeline. We'll click apply and close. And those are the bi-frost options.
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- Colliding with a polygon mesh
- Adding velocity, friction, and drag with motion fields
- Optimizing space and time accuracy
- Caching simulations
- Meshing and exporting liquids
- Render-time meshing in Arnold
- Applying channel data to Arnold shaders
- Generating foam from a liquid
- Rendering and shading foam in Arnold