Load and save liquid simulation parameters.
- [Instructor] 3ds Max fluid presets provide a convenient way to store and retrieve settings for different kinds of liquids, such as water, oil, or syrup. In combination with multiple fluid caches per object, we can easily create variations on fluid sims, and play them back in realtime for review. Let's take a look, I've got a simulation already setup. Select the liquid object in the view port and go to the modify panel, and click the simulation view button, simulation view opens, and we have the default naming for the object, and the first solver.
We're going to create multiple solvers here so let's rename the one that's here. With it selected I can go into the solver menu, and choose rename solver, and let's call it water solver. Renaming the solver has the beneficial side effect of also renaming the directory or folder into which the cache files will be stored. Before we get into the presets for liquids, I wanted to take a detour into the solver parameters.
Let's go into the solver parameters tab, and choose the simulation parameters category, and scroll down into the simulation parameters rollout, because I want to point out that I've already determined the optimal number of transport steps and time steps to accommodate the liquid presets that I'm going to use. I'm going to have a fluid moving at a medium speed which is the water, and also a slow moving fluid, which will be maple syrup, and I've chosen these time steps and transport steps values, so that I will be able to simulate either one of those liquids, without having any issues, such as particles going through colliders.
And it's important that I optimize the settings for all of the various solver settings that I want to use, and that's because if we go into the liquid parameters here, we have the ability to choose a preset, but that preset only effects what we see in the liquid parameters rollout here. And so the simulation parameters need to accommodate anything that I might have in this window. Okay, so we got some presets up here, and we can choose one, down at the bottom just choose water, and then click the button to load the selected preset.
When we do that nothing changed here, we did load the preset but in fact water has the same parameters as the defaults. I can go up here and choose default settings, click that button, and again it looks like nothing happened. But if I choose some other preset, let's say caramel, and load that, we can see that some of these parameters changed, we have a very high viscosity, and that of course is the thickness of the fluid or its resistance to changing shape.
Alright, let's go back to the water, and load that. I want to mention that surface tension, which is the sort of skin of the liquid, is disabled for the default water, and that's simply to speed up the calculations. If we wanted ultimate realism in this shot, we would want to enable the surface tension, because this is a pretty small scale fluid. But I'm going to leave it off just so that our calculations will be faster, for the purposes of demonstrating how presets work, this'll be fine.
Now we can go ahead and run the simulation and store the cache, up here in our solver management area, the only one of the caches that's currently enabled or highlighted is the fluid cache, or liquid component, and the others are turned off, so no foam and no mesh. Click the play button, and that will start to simulate, if you want you can open up the simulation output window from the options, open output window, and this will just give us some data about the running simulation, telling us how long it took to calculate the various components of the frame.
We'll let that run for a few minutes and then check back in, once it's gone up to the final frame of the timeline. Once that simulation is calculated and cached out to disk, we can rewind in the timeline and press play, and take a look, it's a pretty good first attempt at water. Once again if we had enabled surface tension it would've taken longer but would've looked better. These drops would've held together a bit better. But that's a pretty food first attempt and it will suffice to demonstrate the difference between water and maple syrup.
So I'll stop the timeline and rewind it, go back up into solver management area of the simulation view, and with that water solver selected, let's make a clone of it. Go to the solver menu and choose clone solver, and now we've got a copy. We can add as many caches or solvers as we want, per liquid object, but only one of those solvers can be active at any one time, and the active solver is indicated by this blue highlighting.
If we click on water solver copy, now it's the active one, and since it has not been calculated or cached, we see nothing in the view port when we're scrubbing the timeline. With water solver copy selected, we can back into the liquid parameters, and choose another preset. Go to the presets pull down and choose maple syrup, and click the button to load the selected preset. And now surface tension is enabled, with a higher value, and also we have a viscosity value of 3.2.
Before running the simulation let's rename the solver so that it will create the appropriate directory. So go up to water solver copy, and you can access the menus just by right-clicking, choose rename, and I'll call it maple syrup solver, and click okay. Once it's renamed we can go ahead and run that simulation and store the cache. Click the play button to start the solve. We'll let that simulate and check back in in a moment when it's finished.
Once again, when the simulation has calculated the entire timeline, we can rewind and playback, and take a look at the maple syrup, which looks quite a bit different than the water did. Alright now we can switch back and forth of these at any time so I'll just rewind, and choose water solver in the management area, and press play, and now we've got water once again. Rewind, choose the maple syrup solver, and press play.
And that's how easy it is to use different solvers on the same object, and to load in presets. And of course if we go back to those liquid parameters, we can change these to whatever we want, and then store them using the little disk icon there, and if you want to delete your presets of course there's a way to do that, there's a little trash can button here, so that you can manage the presets, that you find in this list. And that's how to use presets in 3ds Max Fluids.