WEBVTT 00:00.300 --> 00:07.500 Let's begin looking at Bifrost, Bifrost is a newer kind of dynamics in. 00:08.400 --> 00:14.700 You can do basically a liquid and arrow, which is kind of smoke or clouds or whatever else. 00:15.090 --> 00:20.610 And you want to make sure that you have this loaded under Windows Settings Preferences plugin manager. 00:20.940 --> 00:22.610 And you can scroll down. 00:22.620 --> 00:24.780 This is kind of towards the bottom. 00:25.170 --> 00:29.370 Is this Bifrost Miah plug ins and you want to make sure all this is loaded. 00:29.790 --> 00:36.030 That way you will have this option under the effects panel here in this lesson, we're going to create 00:36.030 --> 00:38.160 a little bit of liquid. 00:38.170 --> 00:45.150 So let's create a container and an emitter here, go over to poly modeling shelf and create a cube. 00:46.020 --> 00:46.850 Now we have this. 00:46.860 --> 00:48.540 We can see frame up on it. 00:48.540 --> 00:54.240 We can see that we need to take into consideration the scale like we always do with any kind of dynamic 00:54.240 --> 00:54.700 effects. 00:55.140 --> 00:57.000 So with Bifrost, it's no different. 00:57.810 --> 01:02.400 Bifrost, like all dynamics, thinks that one unit is one meter. 01:02.880 --> 01:14.100 And so because this cube by default is one by one by one, it thinks this thing is a meter in size. 01:14.520 --> 01:20.930 So if we're going to simulate, like water into a cup, for example, we need to scale this way down. 01:21.210 --> 01:24.000 So let's just assume maybe a cup is like 10 centimeters. 01:24.300 --> 01:30.200 So you can think of these scale as basically 100 meters. 01:30.210 --> 01:31.770 So imagine two zeroes here. 01:32.070 --> 01:37.040 So if we wanted to get down to 10 centimeters, we need to take a zero out of this. 01:37.440 --> 01:40.530 So by taking a zero out, we can just move the decimal place. 01:40.590 --> 01:42.380 So now we're down to 10 centimeters. 01:42.690 --> 01:47.190 So now we can frame up on this and let's create a little cup here. 01:47.580 --> 01:55.260 Grab this face and we will extrude it and offset that and then extrude it again by hitting G and then 01:55.260 --> 01:56.320 just pull that down. 01:57.690 --> 02:00.120 So now we have our kind of rudimentary cup. 02:00.500 --> 02:01.830 We want to make another cube. 02:02.190 --> 02:03.780 And this is going to be our ometer. 02:04.110 --> 02:09.210 We're going to scale this down to point one and then just kind of hand to scale it from here so that 02:09.210 --> 02:14.030 it is small enough to emit down into the cup that we have created. 02:15.090 --> 02:20.460 So now that we have our Mitta in our container, we need to make the Bifrost fluid with the emitter 02:20.460 --> 02:22.650 selected go to Bifrost fluids liquid. 02:25.080 --> 02:30.750 So now you can see that we have all these new things in our outliner here, and to be honest, it's 02:30.750 --> 02:32.340 not super well organized. 02:32.340 --> 02:34.920 You create one by far from simulation. 02:34.920 --> 02:37.740 You have, you know, all these different things. 02:38.010 --> 02:39.920 So we'll go through each one of them. 02:39.930 --> 02:43.440 But in general, there's only a couple of things you really need to look at to get started. 02:44.070 --> 02:51.420 So when we have our attribute, Ed, open, we can see with the Bifrost liquid we can change the star 02:51.420 --> 02:51.720 frame. 02:51.720 --> 02:57.390 But for us and this lesson, we're going to turn frame one and we want to turn on scratch cash. 02:57.390 --> 03:05.250 And what this does is it simulates the dynamics and the fluids and then it keeps it stored in memory. 03:05.250 --> 03:12.240 So we don't have to simulate simulate it every time, unlike in cloth, for example, where we had to 03:12.240 --> 03:14.760 cash it to disk instead of memory. 03:14.940 --> 03:18.090 So scratch caches will cache it to memory. 03:18.450 --> 03:23.040 And you'll see that when we hit play, this will start to turn green. 03:23.880 --> 03:29.150 The next thing we need to deal with is the default kind of particle shape. 03:29.670 --> 03:37.110 So let's go over to the emitter and we can basically see most every property, even though these are 03:37.110 --> 03:41.640 divided here, we can kind of get to all of them from just going through these tabs. 03:41.850 --> 03:43.800 So we actually get over to the emitter from here. 03:44.190 --> 03:48.000 We want to turn on continuous emission because we just want to see this thing kind of pouring water 03:48.000 --> 03:49.650 out from this emitter here. 03:50.100 --> 03:53.370 And now that's likely to kind of switch the tabs up a little bit. 03:53.370 --> 03:57.530 But we're still in the emitter tab here, even though we are selecting this. 03:57.540 --> 04:01.320 So you can see where you can kind of get the both from different things. 04:01.320 --> 04:02.430 There's a props here. 04:02.460 --> 04:05.820 Or we could select the emitter itself and we still have the emitter tab here. 04:06.270 --> 04:15.680 So the next thing we want to look at again is the kind of voxel size I want to go over to its properties. 04:15.690 --> 04:21.870 We can also get to that with this little button here or this little object and outliner. 04:22.170 --> 04:27.510 So, again, you can get to it from having the virus liquid and go to the properties, or you can just 04:27.510 --> 04:30.070 like the properties as an object in the outliner. 04:31.020 --> 04:33.090 So now we can see our gravity. 04:33.090 --> 04:39.480 We don't need to change because again, we're scaling all of our objects down to accommodate for that 04:39.480 --> 04:41.130 one meter scale. 04:41.430 --> 04:46.160 So we don't need to change the gravity, but we do need to change the master voxel size. 04:46.170 --> 04:53.910 So this is saying, you know, basically if we look at this container, this is the container of a voxel. 04:54.210 --> 04:58.230 So when we reduce this down, you'll see that that cube change sides. 04:58.240 --> 05:05.250 So let's go to something like zero point zero five, and we'll probably need to go even smaller because 05:05.250 --> 05:08.790 when will hit play, you can see that nothing's happening really. 05:09.600 --> 05:18.150 And also for playback, you want to make sure that you're playback speed here is play every frame and 05:18.150 --> 05:19.410 you just get to that right click. 05:19.410 --> 05:24.080 It's off screen, but you can go to playback speed and you can go to play every frame. 05:24.690 --> 05:28.110 And so why is it not simulating anything? 05:28.140 --> 05:34.740 Well, if you think about it, this master voxel size, which a voxel is just a three dimensional pixels, 05:34.740 --> 05:40.890 you can basically think of it like this cube here has a ton of cubes in it. 05:41.010 --> 05:41.440 Right. 05:41.460 --> 05:44.220 And that each of those cubes is a voxel. 05:44.610 --> 05:49.380 So, you know, pixels are an image of voxel is just a three dimensional pixel basically. 05:49.830 --> 05:52.980 So if you think about why, why are we not seeing anything yet? 05:53.010 --> 05:56.700 Well, it's because that voxel size is too big for our emitter. 05:56.700 --> 06:01.230 Our emitter is smaller than our voxel size, so we need to reduce that down even more. 06:01.530 --> 06:02.490 So let's reduce that down. 06:02.500 --> 06:04.710 Now you can see that we've reduced it down. 06:04.710 --> 06:06.510 We can actually see particles here. 06:06.990 --> 06:13.530 So if we go over to liquid Chaib, we get the option to turn on voxels or particles or whatever else, 06:13.740 --> 06:17.250 and we can just increase the particle size here so we can see them a little bit better. 06:17.580 --> 06:26.640 So basically, now that we have this master voxel size set appropriately, it is smaller than our emitter 06:26.640 --> 06:26.910 now. 06:26.910 --> 06:28.920 So now it can actually emit particles. 06:29.190 --> 06:34.230 So now we hit play, we will be able to see it is indeed emitting particles. 06:34.230 --> 06:38.550 But let me just escape out of that because we haven't added this is a collider. 06:38.550 --> 06:40.550 Snout's just going through that. 06:41.040 --> 06:45.780 So the other thing we need to see the green I mentioned earlier, we need to have this thing selected 06:45.780 --> 06:52.440 so now we can see the green and this means we can scrub this now and I'll take immediately take that 06:52.440 --> 06:54.900 back because I clicked on frame one. 06:55.170 --> 07:02.430 And so that's the catchy thing about the scratch cache is if you go back to frame one with a scratch 07:02.430 --> 07:04.710 cache, it will start over. 07:04.950 --> 07:10.830 So any time that I'm playing anything back, I will let me just try to escape this. 07:10.830 --> 07:14.790 This is a this is another thing to be wary of, is trying to escape out of things. 07:14.790 --> 07:16.560 Sometimes it's it won't let you. 07:17.730 --> 07:21.780 So it's smart to bring this down, to limit it. 07:22.530 --> 07:23.280 How far? 07:23.580 --> 07:30.720 In simulators and then also to turn playback to one so it doesn't continuously loop back and start re 07:30.720 --> 07:32.200 scratch caching over again. 07:32.580 --> 07:40.710 So basically the steps are reduced down the range that you really want to see in test and then turn 07:40.710 --> 07:45.900 this to from this is the default from looping and turn it to where you have this little one over here. 07:46.470 --> 07:51.930 And so that way it won't go back to the beginning because again, if I was the click on frame one here, 07:51.930 --> 07:54.120 it would get rid of this all the scratch cache. 07:54.360 --> 07:58.110 So let's say I like this and I want to kind of scrub it. 07:58.230 --> 08:04.200 I'm going to save myself the headache and and fear of getting back to frame one and just turn the timeline 08:04.200 --> 08:06.510 to two so I can't ever get back to frame one. 08:07.140 --> 08:12.960 So now when I scrub, I can actually scrub and see the simulation, whereas if I accidentally hit on 08:12.960 --> 08:15.960 frame one, it's going to delete all that scratch cache. 08:16.230 --> 08:17.560 So that's another thing to look out for. 08:17.580 --> 08:22.530 There's a lot of these little gotcha things that, you know, it's important to kind of keep in mind. 08:22.890 --> 08:27.330 So we want to add this container, a collider now that we have our monitor working. 08:27.570 --> 08:34.140 So we want to have our Bifrost liquid selected and then the geometry and go up to Bifrost fluids and 08:34.140 --> 08:34.930 add a collider. 08:35.250 --> 08:41.430 Now, when we hit play, it should collide with this object and we get another problem. 08:41.460 --> 08:44.250 You have these particles that are. 08:45.800 --> 08:50.660 Going outside of the container and why is that one, how can we fix it? 08:50.670 --> 08:56.000 So let's go into the Bifrost liquid, let's go over to the properties. 08:56.420 --> 08:59.780 And this is another big one to remember. 09:00.110 --> 09:01.900 We basically covered this one. 09:01.910 --> 09:02.980 This is an important one. 09:03.230 --> 09:04.940 And the next one is going to be this one. 09:04.970 --> 09:10.490 This is the transport step adaptivity, which basically means how accurate is this thing going to be? 09:10.820 --> 09:15.890 The higher we go with this number, the more accurate it's going to be, but also the more time intensive 09:15.890 --> 09:17.040 it is going to take to simulate. 09:17.450 --> 09:23.800 So if we just go to something like point five and let's redo the scratch cache, we can test to see. 09:24.200 --> 09:28.490 Now, we do not have those particles that are going outside of the container. 09:29.240 --> 09:33.680 I'm going to let that finish and go to that last frame that I had. 09:33.680 --> 09:37.300 So now I'm not having to, like, frantically hit escape to get it to stop. 09:37.940 --> 09:40.970 So now we can see that indeed the collider is working. 09:41.600 --> 09:44.330 The particles aren't going outside the emitters. 09:44.330 --> 09:48.890 Working gravity is accurate because we've scaled everything down properly. 09:49.280 --> 09:52.250 So the last thing we want to do is create a mesh for this. 09:52.250 --> 09:56.990 We have everything else working, but now we want to render this as a water or something like that. 09:57.440 --> 09:58.310 So let's create a mesh. 09:58.310 --> 10:06.350 We want to click Bifrost Liquid and have the liquid shape tab selected here and we can go down to Bifrost 10:06.350 --> 10:08.390 meshing and this is pretty cool. 10:08.390 --> 10:11.560 We can just click enable and voila, we have a mesh. 10:11.900 --> 10:17.300 So when we hit render we can actually render this thing and now you know how to do Olympic caches. 10:17.540 --> 10:22.400 So you could also actually create an Olympic cache from this, which is pretty amazing. 10:22.400 --> 10:26.960 So that is how to use Bifrost and create a little liquid simulation. 10:27.620 --> 10:35.240 And we can play this back as well with the geometry mesh working. 10:35.540 --> 10:46.610 And in the next lesson, we're going to cover how to use Bifrost with creating smoke for our main animations 10:46.610 --> 10:47.000 scene. 10:47.450 --> 10:49.400 Thanks for watching and I'll see in the next lesson.