WEBVTT 00:06.920 --> 00:08.090 Welcome back. 00:08.270 --> 00:15.290 Now, one of the last things I'd like to cover in this section is what happens when we run behind things. 00:15.320 --> 00:20.690 We have obstacles sometimes, and the default behavior is for the camera to zoom in. 00:20.720 --> 00:23.720 Now, for some types of games, that's fine. 00:23.720 --> 00:24.770 I like that. 00:24.770 --> 00:30.440 But for other types of games, in particular the top down genre, that's not fine. 00:30.440 --> 00:31.470 I don't like it. 00:31.490 --> 00:34.340 I'd like the camera to be essentially fixed. 00:34.340 --> 00:39.320 I mean, it follows the character, but a fixed camera is not going to zoom in. 00:39.620 --> 00:46.610 It's going to stay back, which means that there might be geometry obstructing the view. 00:46.910 --> 00:53.930 So I'm going to make all of my geometry in the world, ignore the camera. 00:53.960 --> 01:01.850 So it's kind of convenient that all of my meshes here are in the same folder as I can just change all 01:01.850 --> 01:02.780 of them at once. 01:02.780 --> 01:09.870 So selecting all of them, I can go to their collision settings and just have them all ignore the camera 01:09.870 --> 01:10.500 channel. 01:10.500 --> 01:17.550 So we're going to go to Collision Presets, set them all to custom and have them all ignore the camera. 01:17.550 --> 01:22.350 And now if I press play, they're not going to block the camera. 01:22.350 --> 01:24.240 But now they're blocking our view. 01:24.240 --> 01:26.130 And that's not good either, right? 01:26.130 --> 01:29.220 So how do we get around this problem? 01:29.660 --> 01:34.520 Well, what a lot of top down games do is they fade out the geometry. 01:34.640 --> 01:42.260 That's the kind of approach that I like because as you're moving behind something, that obstacle fades 01:42.260 --> 01:43.760 out and you can see through it. 01:43.760 --> 01:44.960 That's kind of cool. 01:44.960 --> 01:47.780 And so we're going to come up with that kind of a solution. 01:47.780 --> 01:52.370 Now, something like this tunnel here is a prime example of why we'd want this. 01:52.370 --> 02:00.440 In fact, if we just delete these two pieces and duplicate these shorter pieces and use those instead, 02:00.470 --> 02:04.100 then select everything and move it down a bit. 02:04.130 --> 02:08.420 Now we can see that the problem becomes even more of a concern. 02:08.420 --> 02:17.150 So I'd like to handle creating some kind of actor that we can use to dynamically fade out itself. 02:17.300 --> 02:19.640 So we're going to make an actor for that. 02:19.640 --> 02:28.010 And just like our flame pillar, this is something that is more of a visual designer centric sort of 02:28.010 --> 02:28.850 mechanic. 02:28.850 --> 02:32.100 So we're going to make a blueprint for this. 02:32.100 --> 02:36.360 I'm going to put my fade actor here in the actor folder. 02:36.360 --> 02:42.450 We'll make a sub folder called Fade Actor, and we're going to make a base class for all of our fade 02:42.450 --> 02:48.120 actors and we'll have a new fade actor for each thing that we wish to have the capability of fading 02:48.120 --> 02:48.810 out. 02:48.840 --> 02:51.480 Now let's make that actor. 02:51.480 --> 02:54.300 It's going to be a new blueprint based on actor. 02:54.330 --> 02:58.770 It's going to be called BP, Underscore fade actor. 02:59.700 --> 03:03.720 And our fade actor is going to be simple. 03:03.720 --> 03:05.370 It's going to have a static mesh. 03:05.490 --> 03:07.560 So we're going to add a static mesh. 03:09.000 --> 03:13.680 And we'll just call this mesh and I'll give it a default mesh. 03:13.710 --> 03:16.590 I'm going to give it the perhaps beacon. 03:16.590 --> 03:20.690 And now we just need a way to fade out our actor. 03:20.700 --> 03:22.410 So how are we going to do that? 03:22.440 --> 03:25.680 Well, there are a number of ways we can approach this. 03:25.680 --> 03:30.690 I'd like to approach it from the material side, so I'm going to browse to the material. 03:30.690 --> 03:32.190 It's called M Beacon. 03:32.310 --> 03:37.050 It's actually using a material instance, this particular mesh. 03:37.050 --> 03:42.240 But I'm going to go into M Beacon, the material, not the material instance, but the material that 03:42.240 --> 03:44.910 this material instance is based on. 03:45.300 --> 03:55.440 So here we have a few nodes and we have a material, but I'd like to be able to add the ability to fade 03:55.440 --> 04:00.300 this thing out now in order to be able to fade out the material again. 04:00.300 --> 04:05.340 There are a number of ways to do it, but we want to be careful because there could potentially be a 04:05.340 --> 04:06.630 lot of these in the world. 04:06.630 --> 04:11.860 So changing our type of material could make things more expensive. 04:11.890 --> 04:16.950 One way that we can fade things out is by using opacity and opacity mask. 04:16.960 --> 04:22.660 Now, if we change our blend mode from opaque, we can change it to masked or translucent. 04:22.690 --> 04:30.190 Now masked is going to be a lot cheaper than translucent, so we would prefer masked, but I'd also 04:30.190 --> 04:34.600 prefer not to use a masked material unless we're actively blending out. 04:34.600 --> 04:41.380 So I'd like to have not only my M Beacon and its associated material instance, but I'd also like to 04:41.380 --> 04:46.240 have a fade version that uses masked as its blend mode. 04:46.240 --> 04:50.770 So I'm going to right click on M Beacon and duplicate it and we'll have a fade version. 04:50.770 --> 04:54.610 So this will be M Beacon underscore F for fade. 04:54.640 --> 05:01.360 You'll thank me later for not typing the full word fade because we're going to be doing this for a number 05:01.360 --> 05:02.770 of other materials. 05:03.010 --> 05:04.840 So this is the fade version. 05:04.990 --> 05:06.340 Let's open that. 05:06.340 --> 05:11.260 And here in the fade version we're going to change its blend mode from opaque to masked. 05:11.260 --> 05:15.700 And now we can see if we can figure out a way to fade out. 05:15.700 --> 05:22.300 Using an opacity mask, you see, opacity with a default value of one means that we can't really see 05:22.330 --> 05:23.710 through this material. 05:23.710 --> 05:28.150 And by the way, we can preview this on a given mesh. 05:28.150 --> 05:35.260 If we go to that mesh, for example, we can select some beacon and then come back here in the material 05:35.260 --> 05:40.690 and click on the bottom right icon so that we can preview this with a preview mesh. 05:40.720 --> 05:49.630 Now opacity has a value and we can hold the one key and left click to stick a value into opacity mask 05:49.630 --> 05:50.950 with a value of zero. 05:50.950 --> 05:54.700 Notice it's gone with a value of one notice. 05:54.730 --> 05:57.490 It's back with a value of 0.5. 05:57.490 --> 06:01.330 However, look, it's just the same as if it were one. 06:01.330 --> 06:05.290 And as soon as we get down below a certain threshold, it disappears. 06:05.290 --> 06:09.460 So it's almost like on or off, we can't really fade, right? 06:09.460 --> 06:11.470 So how do we get around that problem? 06:11.770 --> 06:17.260 Well, one way is a node called dither temporal AA. 06:17.620 --> 06:23.500 So this dither temporal AA will sort of dissolve a texture. 06:23.500 --> 06:29.650 If we plug in our value into it, then if we right click on the node and start previewing it, we'll 06:29.650 --> 06:33.970 see that this is what it looks like, kind of almost grainy. 06:34.000 --> 06:39.040 It's like a black and white texture with some sort of static in there. 06:39.040 --> 06:45.500 And if we change that value to say one, well, it's all white, zero is even darker. 06:45.500 --> 06:47.860 0.5 is somewhere in between. 06:47.860 --> 06:50.290 So we can see what this does for us. 06:50.500 --> 06:55.300 Now I'm going to stop previewing it and instead hook it up to my opacity mask. 06:55.300 --> 07:01.750 And now we can really see that you can kind of see through it At 0.5, at 0.1, you can almost not see 07:01.750 --> 07:02.380 it at all. 07:02.380 --> 07:04.620 And at one you can see it completely. 07:04.630 --> 07:10.840 Now, if this were a material parameter, then we could make an instance out of this and then we can 07:10.840 --> 07:12.250 change that dynamically. 07:12.250 --> 07:16.690 So I'm going to right click and convert this to a parameter and call this. 07:16.900 --> 07:20.470 We'll just call it fade and apply that. 07:20.470 --> 07:27.850 And now if we make a material instance of this material in Beacon F, we can right click create material 07:27.850 --> 07:28.480 instance. 07:28.480 --> 07:34.930 I usually prefix these with me for material instance, but in this case, because I want to create quite 07:34.930 --> 07:40.840 a few of these and don't want to have to rename a lot, I'm just going to leave it to Beacon F underscore 07:40.840 --> 07:41.350 inst. 07:41.380 --> 07:48.220 Now I'm going to open this and because I have this fade parameter, I can change it. 07:48.220 --> 07:53.320 I can bring it down to close to zero and see that it fades out in this nice way. 07:53.320 --> 07:54.580 Pretty cool. 07:54.730 --> 07:57.400 Now random is going to change how it fades. 07:57.400 --> 07:59.920 And if you want you can change this random value. 07:59.920 --> 08:04.690 Its default value is one and we can put a value between 0 and 1. 08:04.690 --> 08:07.940 So if I apply that and come back and play with this, you. 08:07.950 --> 08:10.500 You can see what it looks like with a different value. 08:10.500 --> 08:13.620 But I'm okay with leaving that at its default value of one. 08:13.620 --> 08:16.140 Just mentioning that that's a parameter there. 08:16.440 --> 08:22.140 So now I have this material instance that can fade out when it's at one or higher. 08:22.140 --> 08:27.930 It looks normal, but as we fade it out, this is what it looks like right now. 08:27.930 --> 08:32.160 By the way, this pillar, the beacon, has a glow parameter. 08:32.160 --> 08:39.180 And if you raise that, check that out, we get some glow on our rune. 08:39.180 --> 08:42.360 So just pointing that out, something kind of cool. 08:42.360 --> 08:49.770 But now that we have this fade parameter and we can fade this out, we need a way to do this on our 08:49.770 --> 08:50.190 fade. 08:50.190 --> 08:54.840 Actor Now one thing about meshes is they can have multiple materials. 08:54.840 --> 08:58.980 In fact, their materials exist in an array on the mesh. 08:59.070 --> 09:02.880 If we go into our fade actor, I don't need my flame pillar. 09:02.880 --> 09:04.020 I'm going to close that. 09:04.050 --> 09:11.190 My fade actor shows in the details panel the mesh and the materials and it says Element zero. 09:11.190 --> 09:15.660 Some meshes have more than one, so we need to take that into account. 09:15.660 --> 09:16.950 If we're going to make this fade. 09:16.950 --> 09:20.790 Actor We need to treat materials like arrays. 09:20.790 --> 09:28.170 In fact, if we go into the event graph and get our mesh out here and type get materials dragging off 09:28.170 --> 09:31.290 of it, we have get material and get materials. 09:31.290 --> 09:36.110 This returns an array of material interface object references. 09:36.120 --> 09:41.040 So keep in mind that a mesh can have more than one material. 09:41.130 --> 09:44.910 Our fade actor is going to take that into account. 09:45.090 --> 09:53.220 Now, the first thing I'd like to do is get those materials used by this particular mesh and store them 09:53.220 --> 10:00.330 in an array, because if we want to change a material instance dynamically, we have to create a dynamic 10:00.330 --> 10:07.680 material instance and assign that for our materials on the mesh and change those dynamic material parameters 10:07.680 --> 10:08.880 at runtime. 10:08.880 --> 10:15.240 And if I'm fading out and fading back in, when I fade back in, I'd like to replace the materials with 10:15.240 --> 10:16.890 what they were originally. 10:17.070 --> 10:20.280 So they're not always using the masked material. 10:20.280 --> 10:24.060 They can go back to their opaque or whatever they were using originally. 10:24.060 --> 10:31.530 So in the construction script, I'm going to get my mesh and get its materials with get materials. 10:32.930 --> 10:34.950 And store this array. 10:34.970 --> 10:39.860 I'm going to go ahead and drag off and promote this to a variable. 10:40.280 --> 10:43.940 And I'm going to call this original materials. 10:45.020 --> 10:47.360 Now, this is in the construction script. 10:48.100 --> 10:53.170 So every time we change something, we're just going to store all those materials. 10:53.440 --> 10:57.340 Now that I have these stored, I can loop through all of these materials. 10:57.340 --> 10:59.020 I can use a for each loop. 10:59.680 --> 11:06.860 And in this for each loop, what I'd like to do is make a dynamic material instance based on these. 11:06.880 --> 11:13.210 So what I can do is right click and use create dynamic material instance. 11:13.240 --> 11:16.090 This requires a material interface object. 11:16.090 --> 11:17.410 That's what we have. 11:17.680 --> 11:22.790 So for each iteration of the loop, we're creating a new dynamic material instance. 11:22.810 --> 11:28.300 We can leave creation flags at none and we don't need to give it an optional name. 11:28.600 --> 11:35.680 Now, each time we do this, I'm going to want to store it in a dynamic material instance array. 11:35.980 --> 11:43.960 So I'm going to make a new variable and call this dynamic material instances. 11:44.230 --> 11:49.310 And this can be of type material, instance, dynamic. 11:49.550 --> 11:51.440 So we're going to search for that. 11:51.740 --> 11:57.080 It'll be an object reference, but we're going to change this to array right here in the details Panel. 11:57.080 --> 12:02.810 Next to variable type, we're going to select array and we're going to take that array. 12:03.320 --> 12:05.420 And we're going to call Add unique on it. 12:06.680 --> 12:11.750 To add our new material instance dynamic to it. 12:11.960 --> 12:18.740 Now this is done in the construction script, so we don't want to fill this up unless we're going to 12:18.740 --> 12:20.120 use those materials. 12:20.120 --> 12:25.640 So what we can do first thing is clear this array, because we don't know how many times this is going 12:25.640 --> 12:26.590 to be called. 12:26.600 --> 12:31.400 So we're going to take dynamic material instances and call clear. 12:32.480 --> 12:33.200 That way. 12:33.200 --> 12:37.910 Before we go and fill it up, we make sure we clear out whatever we had before. 12:37.940 --> 12:45.680 So now that we'll have our dynamic material instances created based on our original materials, we can 12:45.680 --> 12:49.910 now create the capability to change those material parameters. 12:49.970 --> 12:51.140 So here's what I'm going to do. 12:51.170 --> 12:52.520 I'm going to go into the event graph. 12:52.520 --> 12:58.520 We're going to use event begin play, and I want to loop over my dynamic material instances. 12:58.520 --> 13:07.910 So I'm going to use a for each loop and for each of these I'm going to now set my meshes materials to 13:07.910 --> 13:09.860 these dynamic material instances. 13:09.860 --> 13:16.190 So I'm going to get my mesh and I'm going to call set material and set material takes an element index. 13:16.190 --> 13:21.860 So as we're looping through this array, we're going to use the array index as the element index. 13:21.860 --> 13:23.630 So we're going to hook that up. 13:23.630 --> 13:27.650 And the array element is a material instance dynamic. 13:27.650 --> 13:34.500 We can hook that in and then our mesh will now be using that dynamic material instance. 13:34.740 --> 13:38.610 Now this action here could be its own function. 13:38.610 --> 13:44.670 Basically what we're doing here is we're setting the materials to the dynamic instance. 13:44.670 --> 13:52.110 So I'm going to right click on this and collapse it to a function and call this set materials to dynamic 13:52.140 --> 13:53.340 instances. 13:54.910 --> 14:02.550 Now, as soon as we've done that, we can now set the parameters on these dynamic material instances 14:02.560 --> 14:06.670 so we can take that array of dynamic material instances. 14:07.790 --> 14:10.880 We can loop over it with a for each loop. 14:11.410 --> 14:13.180 And we can set parameters on it. 14:13.180 --> 14:19.720 For example, we can take the array element and we can call set scalar parameter value. 14:21.230 --> 14:23.900 Now this requires the name of the parameter. 14:23.900 --> 14:29.420 And if we go back to our instance, it's called fade, the one I'd like to change so we can change this 14:29.420 --> 14:35.980 to fade and I can set its value to say 0.5 and hook that in. 14:35.990 --> 14:43.280 So now if we have a fade actor on begin play, we should see it faded to about half way. 14:43.280 --> 14:49.640 So I'm going to save all I'm going to browse to my fade actor and drag one into the world. 14:51.420 --> 14:52.890 I'll put one right here. 14:53.040 --> 14:54.210 Press play. 14:55.710 --> 15:02.400 Now I don't see anything, so I'm just going to make sure my dynamic material instances array is not 15:02.400 --> 15:03.300 empty. 15:04.260 --> 15:06.030 So on begin play. 15:06.630 --> 15:08.490 I'm going to get its length. 15:08.970 --> 15:10.110 It should be one. 15:10.870 --> 15:12.310 But I'm going to print that out. 15:14.990 --> 15:17.510 So printing out the length of this array. 15:25.090 --> 15:25.450 Okay. 15:25.450 --> 15:27.730 So it does contain one element. 15:27.730 --> 15:28.870 It's not empty. 15:32.500 --> 15:33.400 Let's see what it looks like. 15:33.400 --> 15:37.090 At 0.5, it should look like this half faded out, basically. 15:38.770 --> 15:41.580 But of course we're not using Beacon. 15:41.910 --> 15:45.940 Instead, we're using the other material instance that we started with. 15:45.970 --> 15:52.390 So really, we need an array of material instances that we can create our dynamic material instances 15:52.390 --> 15:58.060 from here in the construction script, as we can't really use the meshes materials unless we want the 15:58.060 --> 16:01.240 mesh to have those materials from the start. 16:01.240 --> 16:07.210 And our fade versions are based on a material using masked mode. 16:07.210 --> 16:11.650 And I don't necessarily want to use masked except for when we're fading in and out. 16:11.650 --> 16:19.780 So fade actors should have another array in it, and this will be our material instances and more specifically, 16:19.780 --> 16:22.000 our fade material instances. 16:22.000 --> 16:25.180 And this can be of type material instance. 16:25.850 --> 16:27.830 So we're going to change it to that type. 16:27.830 --> 16:33.770 It's an array and this is something we'll have to set and we'll have to make sure to set it in the correct 16:33.770 --> 16:34.520 order. 16:34.580 --> 16:43.700 So if I compile in my fade material instances, I can click plus to add and I can add my m beacon inside 16:43.730 --> 16:50.810 my fade version of the material instance, I can set that there and in the construction script, rather 16:50.810 --> 16:57.050 than looping over our regular materials, we do want to store those in our original materials, but 16:57.050 --> 17:03.030 our for each loop should loop over our fade material instances instead. 17:03.050 --> 17:08.600 Now, if we hook that into our for loop, we're making a dynamic material instance from each of our 17:08.600 --> 17:13.180 fade material instances, and that's going to give us the result we want. 17:13.190 --> 17:19.730 So if I go in, save all press play now I see that it's faded half out. 17:20.650 --> 17:21.940 So that looks pretty cool. 17:22.770 --> 17:23.040 Okay. 17:23.040 --> 17:30.420 So now that we have the ability to set the material instance parameters dynamically, we don't want 17:30.420 --> 17:31.710 to just do it in begin play. 17:31.710 --> 17:34.750 We want to be able to change it at runtime. 17:34.770 --> 17:36.590 Now I don't want to use Tick. 17:36.600 --> 17:39.270 In fact, we don't even need to start with tick enabled. 17:39.270 --> 17:40.620 I'm going to uncheck that. 17:40.650 --> 17:44.010 What I'd like to use instead is another timeline. 17:44.770 --> 17:50.560 So I'm going to get these unused nodes out of the way and I'm going to make a timeline for fading. 17:50.560 --> 17:56.290 So I'm going to right click, I'm going to create a new timeline, and this will be called our fade 17:56.320 --> 17:57.370 timeline. 17:58.680 --> 18:02.120 And the fade timeline is going to have one track. 18:02.130 --> 18:04.830 It's going to be called Fade. 18:06.210 --> 18:08.730 And we'll have two keys on it. 18:08.820 --> 18:11.910 Now, how long we want to fade is up to us. 18:11.940 --> 18:14.550 I'm going to use perhaps half a second. 18:14.580 --> 18:16.710 Maybe one second while testing. 18:16.710 --> 18:19.170 So the length will be one second long. 18:19.200 --> 18:22.860 The first key will be at zero and one. 18:23.340 --> 18:26.950 The second key will be at one and zero. 18:26.970 --> 18:33.480 So this is a fade out timeline and we can highlight both of these, make it an auto curve so it's smooth. 18:33.570 --> 18:37.590 And now we have this one second curve that fades out. 18:38.240 --> 18:40.200 So back to the event graph. 18:40.220 --> 18:43.850 If we play this timeline, I'm going to click play from Start. 18:43.850 --> 18:50.750 And by the way, if I check use last keyframe, this will work nicely in reverse as well as we can reverse 18:50.750 --> 18:52.700 from the last keyframe we were at. 18:52.850 --> 18:58.970 But here in update, I'd like to set the parameter values to the fade on the curve. 18:59.000 --> 19:02.930 Now this set materials to dynamic instances. 19:02.930 --> 19:04.580 This doesn't have to be done. 19:04.580 --> 19:05.780 Every update. 19:05.780 --> 19:08.210 This can be done before we start the curve. 19:08.450 --> 19:14.300 So I'm going to put it right here before play from start and on the update, we're going to loop through 19:14.300 --> 19:15.350 each of our materials. 19:15.350 --> 19:21.890 There's only one in this actor, but we're going to use the fade amount and set the scalar parameter 19:21.890 --> 19:22.600 value. 19:22.610 --> 19:27.230 So we should see our pillar fade out over the course of one second. 19:27.380 --> 19:29.240 And there it goes and it's gone. 19:29.270 --> 19:30.320 Pretty cool. 19:30.680 --> 19:33.680 So I'd like to make this a custom event. 19:33.680 --> 19:39.270 So I'm going to right click custom event and call this Fade Out. 19:39.510 --> 19:49.410 So now we have a fade out event that we can call to fade out, and I'd like a fade in event. 19:49.410 --> 19:56.100 So I'm going to make another custom event called Fade In, and this one can play in reverse. 19:56.950 --> 20:01.530 And in fact, our fade out doesn't have to play from start. 20:01.540 --> 20:07.690 If we play and use the last keyframe, then we can fade out and in and it doesn't matter where we are 20:07.690 --> 20:13.120 on the curve, we'll resume where we last were and go forward or backward, depending on if we're fading 20:13.120 --> 20:14.470 in or out. 20:15.000 --> 20:20.280 Now, if we're fading back in, we've already set the materials to use the dynamic instances. 20:20.280 --> 20:26.430 But really, I'd like to set those materials back to their original materials because those might not 20:26.430 --> 20:29.450 be masked, they might be opaque. 20:29.460 --> 20:37.800 So what I'll do is when our curve is finished, if our fade amount is back to one, in other words, 20:37.800 --> 20:41.810 we'll do a greater than or equal because I never do equals with floats. 20:41.820 --> 20:45.900 If it's greater than or equal to one, we'll have a branch here. 20:46.880 --> 20:48.680 And on finished. 20:48.710 --> 20:51.340 This means we've just finished fading back in. 20:51.350 --> 20:57.710 So in that case I'd like to take my original materials and do a for each over them. 20:58.460 --> 20:59.960 And for each of them. 21:00.630 --> 21:04.620 I'm going to take my mesh and I'm going to set its material. 21:04.620 --> 21:06.480 So call set material. 21:08.320 --> 21:10.390 And we'll set the materials all back. 21:10.390 --> 21:14.730 So we're going to use the array element and the array index in the for loop. 21:14.740 --> 21:19.840 So this is basically resetting all the materials back to their defaults. 21:19.840 --> 21:21.540 So this can be its own function. 21:21.550 --> 21:25.600 I'm going to collapse it and say reset materials. 21:26.050 --> 21:28.090 That's good reset materials. 21:28.630 --> 21:38.170 Okay, so now we have a fade out and a fade in so we can test this out by calling fade out and begin 21:38.170 --> 21:44.080 play and then perhaps doing a delay by a second. 21:44.110 --> 21:46.540 I think our timeline is one second long. 21:46.540 --> 21:47.410 Yes. 21:47.470 --> 21:49.150 So we'll do a second delay. 21:49.150 --> 21:53.560 And as soon as that fade out has completed, we'll do a fade in. 21:54.180 --> 21:56.940 And we'll see that mesh come back. 21:56.940 --> 22:01.670 And by the time that finishes, we should reset the materials to their originals. 22:04.740 --> 22:07.640 All right, let's save all and let's see this fade out. 22:07.650 --> 22:08.400 There it goes. 22:08.400 --> 22:09.660 And it's back. 22:09.720 --> 22:14.130 So we now have the ability to fade out and fade in. 22:14.520 --> 22:15.870 And that's great. 22:16.620 --> 22:19.560 Now I'd like to take collision into account. 22:19.590 --> 22:26.100 You see, if something's faded out, I want to be able to move my mouse and say there's an enemy back 22:26.100 --> 22:26.730 there. 22:26.850 --> 22:28.950 I'd like to hover over that enemy. 22:28.950 --> 22:34.620 And if this wall is faded out, I don't want it to block my cursor Trace. 22:34.620 --> 22:36.740 I want to still be able to trace through it. 22:36.750 --> 22:46.350 So while faded out, I want this mesh in my fade actor to ignore visibility and when I fade back in, 22:46.350 --> 22:48.150 I want to block visibility. 22:48.330 --> 22:56.220 So what we'll do here is in the finished after we've checked to see whether we should reset our materials. 22:56.220 --> 23:02.820 If we're fading back in, I'm going to take my mesh and I'm going to call set collision response to 23:02.820 --> 23:03.630 channel. 23:04.360 --> 23:10.090 Choosing visibility and I'm going to set it to block We're going to block the visibility channel. 23:10.120 --> 23:18.100 However, in our case here, we'll have another branch in our false case and we're going to check the 23:18.100 --> 23:21.340 fade amount to see if it's zero. 23:21.340 --> 23:23.590 So less than or equal to zero. 23:24.750 --> 23:32.460 And that means we've just faded all the way out, in which case we're going to set our mesh to ignore 23:32.460 --> 23:33.450 visibility. 23:33.660 --> 23:35.970 So visibility ignore. 23:36.210 --> 23:39.750 And so this is all stuff we can do on finished. 23:39.750 --> 23:45.600 So we're going to highlight all of these collapse to function and call this fade finished. 23:47.970 --> 23:51.260 Actually, I don't need two inputs, do I? 23:51.270 --> 23:52.260 These are both the same. 23:52.260 --> 24:00.780 So what I'm going to do is control Z that and to fix that, what we can do is we can have a root node 24:00.780 --> 24:03.690 and have this come out of it like that. 24:05.400 --> 24:10.890 And then highlight these again including the reroute node and collapse these to a function. 24:10.890 --> 24:14.910 And now it has a single input and this will be fade finished. 24:17.290 --> 24:21.760 So now our blueprint is looking under control and of course, retesting. 24:21.760 --> 24:22.600 It fades out. 24:22.600 --> 24:23.440 It fades in. 24:23.470 --> 24:24.340 Perfect. 24:24.430 --> 24:31.050 Now that we have a fade actor, all we need to do is decide when to fade it out and fade it back in. 24:31.060 --> 24:34.270 Because Beginplay is not the place to do it, right? 24:34.300 --> 24:38.920 We want to do it as our character goes behind it, right? 24:38.920 --> 24:43.780 So if it's obstructing our view from the camera, then we want to fade it out. 24:43.780 --> 24:47.230 So that is something we'll handle in the next video. 24:47.260 --> 24:48.500 Excellent job. 24:48.520 --> 24:49.630 I'll see you soon.