WEBVTT 00:06.860 --> 00:07.970 Welcome back. 00:08.150 --> 00:11.490 We now have a hit React and that's a gameplay ability. 00:11.510 --> 00:18.770 I'd now like to implement death for when an enemy has its health reduced down to zero. 00:18.800 --> 00:26.030 In other words, here in the attributes set when be fatal is true, we want to call some sort of function 00:26.030 --> 00:27.920 for the character to die. 00:28.070 --> 00:32.370 Now, death is something that ora and enemies should share. 00:32.390 --> 00:35.960 So I'd like to add a function to the combat interface. 00:35.960 --> 00:43.910 So I'm going to go ahead and close all tabs for now and open the interaction folder and get my combat 00:43.910 --> 00:45.470 interface open here. 00:45.470 --> 00:48.870 And I'm going to declare a new function here. 00:48.890 --> 00:54.200 It's going to be a virtual function void, and I'm going to call it Die. 00:54.500 --> 01:01.700 I'll go ahead and make it a pure virtual function so that it has to be implemented and we'll first implement 01:01.700 --> 01:04.520 this in our character base. 01:04.640 --> 01:10.620 So I'm going to go into the character folder and open or a character base and all the way up at the 01:10.620 --> 01:13.440 top, I'm going to override it here. 01:13.470 --> 01:18.300 Virtual void die override, and we can handle what happens here. 01:18.480 --> 01:21.570 Now, in Die, I'd like to drop the weapon. 01:21.570 --> 01:23.310 That's something we can do in Die. 01:23.310 --> 01:25.620 But I'd also like to ragdoll the enemy. 01:25.620 --> 01:29.880 This allows us to get away with not really needing to play a death montage. 01:29.880 --> 01:32.000 We know how to play montages. 01:32.010 --> 01:38.280 In fact, we could just make a death gameplay ability that does pretty much the same thing that our 01:38.280 --> 01:39.480 hit React does. 01:39.660 --> 01:44.500 But for death, I'm going to decide to implement this differently. 01:44.520 --> 01:47.190 I'd like to ragdoll the enemy instead. 01:47.220 --> 01:52.570 Now, if we ragdoll the enemy, we're going to need to do things on the server and on the client. 01:52.590 --> 01:57.510 So for that reason I'm going to create a multicast RPC. 01:58.520 --> 02:02.900 So this function is going to also be a virtual function. 02:02.930 --> 02:04.490 Virtual void. 02:04.550 --> 02:09.290 And I'm going to call this multicast handle death. 02:10.140 --> 02:16.190 So we can override this in child classes if we want to do things in child classes specifically. 02:16.200 --> 02:23.880 But this is going to be what we use to handle what happens on all clients whenever a character dies. 02:23.910 --> 02:26.160 Now this needs to be a new function. 02:26.160 --> 02:34.410 If we're going to make this a multicast RPC, we need to add net multicast to the function and specify 02:34.410 --> 02:37.140 whether it should be reliable or unreliable. 02:37.260 --> 02:39.720 I think death should be reliable. 02:39.840 --> 02:46.260 Now I'm going to implement this function and when I generate the definition, writer is going to make 02:46.260 --> 02:51.930 the definition have implementation that's required for the multicast RPC. 02:51.960 --> 02:58.350 It has to have that implementation there so we can handle what happens on all machines, client and 02:58.350 --> 03:06.150 server in the multicast handle death implementation and then the die function can handle what happens 03:06.150 --> 03:10.690 specifically on the server and then we'll only call die on the server. 03:11.050 --> 03:18.220 So the die function is going to call multicast handle death so we can put that there. 03:18.520 --> 03:23.020 And before we call multicast handle death, we can detach the weapon. 03:23.020 --> 03:31.300 I'd like to drop the weapon so we can take that weapon variable and call detach from component. 03:31.930 --> 03:40.930 And this requires f detachment transform rules so we can make one f detachment transform rules and the 03:40.930 --> 03:43.000 F detachment transform rules. 03:43.000 --> 03:47.200 Struct has a constructor that requires an E detachment rule. 03:47.470 --> 03:52.450 I'm going to pass one in so E detachment rule I'm going to use keep world. 03:52.570 --> 04:02.050 So the weapon can keep the world transform and we have a bool be in call modify that we can pass in 04:02.050 --> 04:03.130 true for. 04:03.490 --> 04:10.360 So this will result in detaching the weapon and that detachment is something that will automatically 04:10.360 --> 04:12.550 be a replicated action. 04:12.550 --> 04:17.380 So if we detach on the server, we don't have to detach on clients. 04:17.380 --> 04:23.770 But there are a number of things I want to do that we can't just do on the server we have to do on the 04:23.770 --> 04:25.000 server and clients. 04:25.000 --> 04:30.190 That's why we're calling multicast handle death and in multicast handle death. 04:30.190 --> 04:33.350 This is where I'd like to ragdoll the character. 04:33.350 --> 04:38.330 In other words, simulate physics for the character and the weapon for that matter. 04:39.050 --> 04:42.020 So in multicast, handle death, we're going to take the weapon. 04:42.020 --> 04:45.290 We're going to call, set, simulate physics passing in. 04:45.290 --> 04:46.040 True. 04:46.040 --> 04:48.020 And I'm going to enable gravity. 04:48.020 --> 04:51.710 So we're going to call, set, enable gravity passing in. 04:51.710 --> 04:55.150 True, making sure that that weapon drops. 04:55.160 --> 05:00.470 Now, we can also enable collision for the weapon as it's not going to have collision. 05:00.470 --> 05:02.990 We've set that to no collision by default. 05:02.990 --> 05:09.380 But now we can set collision enabled and we can pass in collision enabled. 05:10.520 --> 05:17.180 And we can choose physics only as we don't really care about any spatial queries, no overlap events, 05:17.180 --> 05:18.170 anything like that. 05:18.170 --> 05:19.570 We just want physics. 05:19.580 --> 05:24.020 Now our weapon provided that it has a physics asset. 05:24.020 --> 05:28.430 If it's a skeletal mesh, which it is, we'll bounce around on the ground. 05:28.430 --> 05:30.380 And that's the effect I'm going for. 05:30.650 --> 05:36.650 Now I'd like to ragdoll the mesh as well, which means I'm going to need to call, get mesh and enable 05:36.650 --> 05:41.060 gravity on the mesh so we can call, set, enable gravity. 05:41.090 --> 05:43.160 We can enable physics as well. 05:43.160 --> 05:44.330 So get mesh. 05:46.020 --> 05:49.170 Set simulate physics passing in. 05:49.170 --> 05:49.500 True. 05:49.500 --> 05:51.040 And just to be consistent. 05:51.060 --> 05:55.380 I'm going to call, set, simulate physics first, just like I did up here with the weapon. 05:55.380 --> 05:57.660 It doesn't matter which order we call these in. 05:58.620 --> 06:04.290 And what I'd like to do is get the capsule and disable collision for the capsule. 06:04.290 --> 06:11.790 So I'm going to call get capsule component and call set collision enabled. 06:11.790 --> 06:12.690 Passing in. 06:12.900 --> 06:14.150 Collision enabled. 06:14.160 --> 06:15.300 No collision. 06:17.640 --> 06:25.020 So that way the capsule will not be blocking other characters or other objects from passing through 06:25.050 --> 06:25.380 it. 06:25.410 --> 06:32.340 Now, in addition to this, I'd like to use set collision enabled passing in physics only for the mesh 06:32.340 --> 06:33.150 as well. 06:33.180 --> 06:39.360 So we'll do all the things we want to do to the mesh first before messing with the capsule. 06:39.390 --> 06:48.180 So after set enabled gravity, we'll call, get mesh and call set collision enabled using physics only. 06:48.180 --> 06:54.180 So we'll go ahead and do that as the mesh has no collision by default, just like the weapon. 06:54.940 --> 07:01.660 And I'd like to set the collision response to the world static channel for the mesh to block. 07:01.690 --> 07:12.280 So we're going to call get mesh, set, collision response to channel and we'll use EC world static 07:12.580 --> 07:16.210 as that's going to be the walls and the floors and things like that. 07:16.240 --> 07:23.530 We're going to set the response to block and then later, if we wish to implement some kind of impulse, 07:23.530 --> 07:27.280 then we can fling the body in a specific direction. 07:27.280 --> 07:29.980 So that's something we can think about doing later. 07:29.980 --> 07:32.920 But for now, we're just ragdolling the enemy. 07:33.430 --> 07:40.060 So now we have this nice interface function, Di and it's implemented here in Aura Character base. 07:40.090 --> 07:47.470 We can override it to get additional behavior in child classes such as Aura Enemy, for example. 07:47.470 --> 07:49.180 And I'd like to do that as well. 07:49.190 --> 07:55.970 I'm going to copy virtual void die override from the character base and go into Aura Enemy. 07:56.150 --> 08:00.890 And here for the combat interface, I'm going to override die. 08:01.550 --> 08:03.380 We're going to generate the definition for it. 08:03.410 --> 08:04.940 We do want to call super Die. 08:04.970 --> 08:07.100 There's lots of good stuff happening there. 08:07.370 --> 08:11.110 But for the enemy, I'd like to set its lifespan. 08:11.120 --> 08:18.740 So we're going to call set lifespan and we can set the lifespan to some value, say five seconds, or 08:18.740 --> 08:25.660 we can make this a parameter on the enemy and set it to that, since parameters in general are better, 08:25.670 --> 08:28.670 let's just really quickly add a parameter. 08:28.670 --> 08:35.750 We'll copy base, walk speed and we'll create a float called Lifespan. 08:36.110 --> 08:42.860 We'll set it to five by default and I'd like this to be edit anywhere. 08:44.610 --> 08:48.210 And we'll leave it at Blueprint read only it can be in category combat. 08:48.240 --> 08:49.530 That's fine. 08:49.530 --> 08:52.500 And we'll use this here in Die. 08:52.710 --> 08:59.010 So we're going to set the lifespan and then call super die, which will result in the ragdolling. 08:59.610 --> 09:00.360 Okay. 09:01.200 --> 09:06.000 I'm going to compile really quick just to make sure there aren't any compiler errors that I may have 09:06.000 --> 09:06.780 missed. 09:08.350 --> 09:09.790 And it looks like we're good. 09:09.880 --> 09:17.230 So now we have an interface function that we can use, and I'd like to use this in my attribute set. 09:17.230 --> 09:20.920 So I'm going to go into Ora attribute set dot CPP. 09:21.340 --> 09:25.030 And here we know if the damage caused was fatal. 09:25.330 --> 09:30.430 If it is fatal, then we can easily call that interface function. 09:30.850 --> 09:33.850 Now let's take a look at our props struct. 09:33.850 --> 09:37.210 It's called f effect properties. 09:37.540 --> 09:42.780 Now we didn't bother adding a pointer to the interface, the combat interface. 09:42.790 --> 09:44.000 That's fine. 09:44.020 --> 09:49.060 We can call this function if the target actor implements the interface. 09:49.180 --> 09:52.450 So here's what I'll do is I'll say if be fatal. 09:54.560 --> 09:56.420 And then we'll have an else case. 09:56.810 --> 10:03.020 And then this stuff that was in the if not be fatal that can go just in the else case. 10:03.230 --> 10:08.360 And then we don't have to check if not be fatal, we can just check if be fatal. 10:08.480 --> 10:10.380 Then here we're fatal. 10:10.400 --> 10:12.710 Otherwise we're hit reacting. 10:12.710 --> 10:17.060 And if we're fatal, we can get the target actor from props. 10:17.090 --> 10:20.930 Props Dot, Target, Avatar actor. 10:21.170 --> 10:23.750 And we can see if it implements the interface. 10:24.200 --> 10:27.020 So we can say I combat interface. 10:29.170 --> 10:33.250 Combat interface equals cast to AI. 10:33.280 --> 10:34.720 Combat interface. 10:36.010 --> 10:37.600 And we'll cast props. 10:37.930 --> 10:38.440 Target. 10:38.440 --> 10:39.010 Avatar. 10:39.010 --> 10:39.730 Actor. 10:42.760 --> 10:53.590 And if the thing being damaged is a combat interface, we can call combat interface die just like that. 10:53.740 --> 10:58.840 And then once damage is fatal, we should see the character ragdoll. 10:58.870 --> 11:01.460 So now we can compile and test this out. 11:01.480 --> 11:08.350 But our firebolt has ability level one, so it's only doing five damage. 11:08.440 --> 11:14.560 We can up the amount of damage we're doing so we can test death a little easier by going to abilities 11:14.560 --> 11:16.480 or a projectile spell. 11:16.480 --> 11:24.740 And instead of passing in the ability level again, we can pass in a higher value for our scaled damage. 11:24.760 --> 11:32.050 Why don't we pass in a value of, say, ten and that way we'll have a higher value for damage and we 11:32.050 --> 11:34.240 can get to that death a lot easier. 11:34.540 --> 11:39.850 So let's compile and launch this and see if we can trigger that death function. 11:41.390 --> 11:43.150 Okay, we're back in the editor. 11:43.160 --> 11:47.990 I'm going to click open, although I don't think I need any of these assets. 11:48.020 --> 11:51.320 All I really want to do is test out death. 11:51.320 --> 11:58.190 So I'm going to launch a fireball, do some damage, and let's see if we can get this guy down to zero 11:58.190 --> 11:58.940 Health. 11:59.180 --> 12:00.860 One more should do it. 12:00.980 --> 12:03.680 And they ragdoll Look at that. 12:05.330 --> 12:08.900 And of course we set the lifespan to five seconds as well. 12:08.900 --> 12:11.210 So that's another cool thing that we're doing. 12:11.300 --> 12:14.720 We see that they're dropping the weapon as well. 12:14.930 --> 12:17.870 So this is looking pretty nice. 12:18.920 --> 12:24.650 Okay, so we now have a death mechanic working and of course we have a few more things we're going to 12:24.650 --> 12:25.880 want to implement. 12:25.910 --> 12:28.850 Of course we're going to want to gain experience points. 12:28.850 --> 12:33.800 When something dies, we're going to get to all those important RPG mechanics. 12:33.800 --> 12:41.690 But in the meantime, we'll take care of showing a few more really cool cosmetic effects, such as dissolving 12:41.690 --> 12:43.130 the character away. 12:43.130 --> 12:45.860 And we'll get to those things in the videos to come. 12:45.860 --> 12:49.160 So excellent job and I'll see you soon.