WEBVTT 00:07.390 --> 00:08.720 Welcome back. 00:08.740 --> 00:13.850 So we're setting up our ability system components and we've set our replication mode. 00:13.870 --> 00:20.110 Now, something should still be bothering you at this point, and that is that our Aura character base 00:20.110 --> 00:25.930 class has an ability system component pointer and an attribute set pointer. 00:25.930 --> 00:34.240 And it's only on Aura Enemy that those pointers have been set with valid values for Aura character. 00:34.330 --> 00:41.620 Those pointers are uninitialized because we constructed the ability system component and attribute set 00:41.620 --> 00:46.210 on the player state instead for our player controlled character. 00:46.240 --> 00:51.550 These pointers have valid values for the player state, but not for the character. 00:52.090 --> 00:54.880 So I want that to keep bothering you. 00:54.910 --> 01:00.100 Keep that in the back of your mind, because it's something we do want to fix. 01:00.220 --> 01:07.210 Now, another thing we have to do is make sure that the ability system component itself knows who its 01:07.210 --> 01:08.650 owner is. 01:08.680 --> 01:15.070 Now, that could mean something different for our enemy versus our player controlled character, right? 01:15.070 --> 01:21.330 Because for our enemy, the owner of the ability system component is clearly this enemy class. 01:21.340 --> 01:25.660 But for the character, that's not necessarily the case, is it? 01:25.660 --> 01:32.020 Because the player state is who actually constructs the ability system component? 01:32.380 --> 01:35.590 So how do we decide who's the owner of it? 01:35.620 --> 01:37.300 Let's talk about that. 01:37.330 --> 01:43.510 Now the Ability system component has this concept of ability actor info. 01:43.540 --> 01:51.910 That way, the ability system component can always know the actor info such as who owns this ability 01:52.010 --> 01:53.360 system component. 01:53.450 --> 02:01.160 But the ability system component also understands the concept that it might be owned by some actor, 02:01.160 --> 02:07.430 by some pawn, or it could be owned by another type of entity such as a player state. 02:07.520 --> 02:16.370 So for that reason, the ability system component has two variables an owner actor and an avatar actor. 02:16.730 --> 02:22.570 You see, the owner actor is whatever class actually owns the ability system component. 02:22.580 --> 02:30.890 But the Avatar actor is the representation in the world associated with this ability system component. 02:31.130 --> 02:39.440 Now for our enemy character, these two are the same because our enemy character class is the class 02:39.440 --> 02:42.500 that constructs our ability system component. 02:42.500 --> 02:49.330 So the owner actor is the enemy character, and the avatar actor is also the enemy character. 02:49.340 --> 02:51.290 That's what we see in the world. 02:51.290 --> 02:53.240 That's the visual representation one. 02:53.270 --> 03:00.020 Now for the player controlled character, this is a little different because our ability system component 03:00.020 --> 03:06.110 is constructed by the player state, and that's the class we would like to think of as the owner for 03:06.110 --> 03:07.960 the ability system component. 03:07.970 --> 03:15.200 So the owner actor in this case should be the player state and the avatar actor, that actor that we 03:15.200 --> 03:18.890 actually see in the world that should be the character. 03:19.040 --> 03:26.300 So in this case, the owner, actor and Avatar actor are two different actors and the ability system 03:26.300 --> 03:29.690 component distinguishes between those two. 03:29.720 --> 03:38.090 So it's important to understand that the owner, actor and avatar actor may or may not be the same actor 03:38.390 --> 03:41.510 in our project For the Enemy, they are the same. 03:41.510 --> 03:45.080 And for the player controlled character, they are different. 03:45.110 --> 03:48.350 Now we are the ones who decide these things. 03:48.350 --> 03:53.680 We call the function to set the owner and avatar actors. 03:53.680 --> 03:59.800 It's a function on the ability system component called init ability actor info. 04:00.010 --> 04:06.250 So we need to initialize the ability system component with these actors ourselves. 04:06.280 --> 04:09.970 Now where and when do we call this function? 04:10.210 --> 04:13.390 Well, that's something that we have to give some thought to. 04:13.420 --> 04:15.580 You see, it depends. 04:16.020 --> 04:21.880 Now here are some rules of thumb and good places to do so in a multiplayer game, the first thing we 04:21.880 --> 04:28.660 need to know is that calling init ability actor info must be done after possession. 04:28.660 --> 04:33.270 In other words, the controller has to have been set for the pawn. 04:33.280 --> 04:38.190 So it's important that we do this after the controller has been set for the pawn. 04:38.200 --> 04:39.640 So when is that? 04:39.670 --> 04:47.440 Well, for a player controlled character in which the ability system component lives on the pawn itself, 04:47.440 --> 04:54.980 this would be if perhaps we had constructed the ability system component on a character instead of the 04:54.980 --> 04:56.960 player state, which we're not doing. 04:56.960 --> 05:04.790 But if we did a good place to call init ability actor info would be in the possessed by function on 05:04.790 --> 05:05.720 the pawn. 05:05.930 --> 05:13.250 This ensures that the ability system component is initialized with the avatar actor and owner actor 05:13.250 --> 05:18.740 values on the server, but this function only applies on the server. 05:18.770 --> 05:19.720 On the client. 05:19.730 --> 05:21.580 We have to use a different function. 05:21.590 --> 05:24.980 There's a function called acknowledge possession for that. 05:24.980 --> 05:28.880 And in this function we know that possession has occurred. 05:28.880 --> 05:32.060 Our pawn does have a valid controller. 05:32.060 --> 05:39.080 So in this case, if we were to put our ability system component on the pawn or in our case the character 05:39.080 --> 05:47.000 class itself, these two functions are where we would call init ability actor info in order to initialize 05:47.000 --> 05:50.390 the ability system so it knows who its owners are. 05:50.420 --> 05:51.140 Both. 05:51.270 --> 05:52.980 The owner and the avatar. 05:52.980 --> 05:55.350 And in this case, they would both be the same. 05:55.350 --> 05:57.930 They would be the pawn itself. 05:58.050 --> 06:04.020 Now, for player controlled characters in which the ability system component lives on the player state, 06:04.020 --> 06:11.130 which is our case for Aura character, then we're going to call init ability actor info for the server 06:11.160 --> 06:12.450 on possessed by. 06:12.480 --> 06:19.980 But for the client we're not going to use acknowledge possession we're going to use on rep player state. 06:20.010 --> 06:20.610 Why? 06:20.640 --> 06:25.440 Because our AC our ability system component lives on the player state. 06:25.440 --> 06:31.950 So not only do we need to make sure that our controller has been set, but we also need to make sure 06:31.950 --> 06:36.720 that our player state is valid at this point in time as well. 06:36.720 --> 06:39.450 Now on Rep, Player State is safe. 06:39.450 --> 06:43.650 Both of those things will have been done by that point in time. 06:43.650 --> 06:46.440 We'll have a valid controller and a valid player. 06:46.440 --> 06:51.030 State Now on rep Player state is something called a rep. 06:51.030 --> 06:58.280 Notify the rep notifies are functions that are called as a result of something being replicated. 06:58.280 --> 07:04.730 In this case, the player state will have been set on the server and the player state is a replicated 07:04.730 --> 07:12.290 entity, which means that as soon as that player state has been set for our pawn, that will be replicated 07:12.290 --> 07:18.140 down, triggering this rep notify, which will be called in response to the replication happening. 07:18.140 --> 07:25.010 And at that point we know that our player state has been set on the server and down here on the client 07:25.040 --> 07:28.610 it's been replicated down and it's a valid pointer. 07:28.610 --> 07:36.140 So that is where we will initialize ability actor info for our ability system component. 07:36.260 --> 07:43.040 And in this case we'll be setting our owner actor to the player state and our avatar actor to the pawn 07:43.040 --> 07:45.770 itself in our case, or a character. 07:45.770 --> 07:49.910 So this is what we'll be doing for our player controlled character. 07:50.300 --> 07:56.050 Now for the AI controlled characters, it's a bit more simple for our AI controlled characters. 07:56.050 --> 07:59.830 We'll have our ability system component on the pawn itself. 07:59.830 --> 08:01.360 That's our aura enemy. 08:01.360 --> 08:09.010 And because of that we really only need to call init ability actor info and begin play. 08:09.010 --> 08:16.840 We know that our AI controlled character is going to have a valid ability system component and controller 08:16.840 --> 08:21.250 and we're just going to call init ability actor info and begin play. 08:21.250 --> 08:24.670 This will work just fine for our AI controlled character. 08:24.670 --> 08:26.350 So that's what we're going to do. 08:26.380 --> 08:32.020 So if you're a note taker, if you like taking notes, this would be one of those important things to 08:32.020 --> 08:38.350 write down so you can pause the video and write these things down because these are the functions that 08:38.350 --> 08:44.290 you want to know about when it comes to calling an IT ability actor info and initializing it. 08:44.290 --> 08:52.240 And now that we know what we're going to do to init ability actor info, it's time to actually do it 08:52.240 --> 08:53.590 in our project. 08:53.590 --> 08:56.710 And this is going to be your quest. 08:56.830 --> 09:03.700 I want you to initialize the actor info by calling init ability actor info and you're going to do this 09:03.700 --> 09:05.500 for the aura enemy class. 09:05.500 --> 09:06.790 That's going to be easy. 09:06.790 --> 09:08.860 You'll just do it and begin play right? 09:08.860 --> 09:11.680 But also handle this for Aura character. 09:11.680 --> 09:15.130 And remember, this one's a little bit more complicated. 09:15.130 --> 09:17.380 And also remember the ASC. 09:17.410 --> 09:22.210 The ability system component is on the player state, which means you're going to need to access the 09:22.210 --> 09:23.200 player state. 09:23.200 --> 09:29.800 And while you're at it, this is a great opportunity to set the Aura character's ability system component 09:29.800 --> 09:31.930 and attribute set pointers. 09:31.930 --> 09:35.320 Remember I told you that should be bothering you in the back of your mind. 09:35.350 --> 09:37.510 Those pointers are uninitialized. 09:37.510 --> 09:43.900 Well, as soon as we access the player state, we should then have access to the ability system component 09:43.900 --> 09:45.460 and attribute sets. 09:45.460 --> 09:51.550 The player state has getters for those and our Aura character will now have the ability to set those 09:51.550 --> 09:52.330 pointers. 09:52.330 --> 09:56.260 So pause the video and initialize your ability. 09:56.260 --> 09:58.420 Actor info now. 10:02.690 --> 10:04.610 Okay, so we're ready to init. 10:04.640 --> 10:06.170 Ability actor info. 10:06.170 --> 10:10.190 And I'd like to do the enemy first because that's the simplest case. 10:10.190 --> 10:13.370 We're going to do this in begin play now. 10:13.430 --> 10:18.830 Our enemy doesn't have begin play, which means we're going to need to override that here. 10:19.100 --> 10:23.740 And while I'm at it, I'd like to make this a little more organized. 10:23.750 --> 10:32.810 I'm going to put a comment up here above our interface functions because I know that this belongs to 10:33.260 --> 10:34.700 our enemy interface. 10:34.700 --> 10:38.090 So I'm going to say enemy interface right here. 10:38.090 --> 10:44.480 And I'm going to put a comment below these two that says End enemy interface. 10:44.480 --> 10:49.670 That way I know that these are from that interface and these are public. 10:49.700 --> 10:51.050 Begin play is protected. 10:51.050 --> 10:56.510 So we'll make a protected section and we'll override begin play down here. 10:56.510 --> 11:03.150 So we're going to say virtual void begin play override. 11:03.150 --> 11:11.670 Let's generate the definition, we'll get our super call and then we can init ability actor info here. 11:11.670 --> 11:21.180 So to do that we access our ability system component pointer and we call init ability actor info and 11:21.180 --> 11:29.010 we can see that the first input is the owner actor that will be this and the avatar actor will also 11:29.010 --> 11:30.420 be this. 11:30.690 --> 11:33.660 Now if you like, you can check the pointer first. 11:33.660 --> 11:39.030 You can even put an assert such as check ability system component. 11:39.030 --> 11:40.230 You can do that. 11:40.350 --> 11:43.860 But if I get a crash on this line, then I know why. 11:43.860 --> 11:49.950 It's because the ability system component pointer is null, but I don't expect it to be null because 11:49.950 --> 11:53.250 I'm initializing that in the constructor. 11:53.250 --> 11:55.440 So something is terribly wrong. 11:55.440 --> 12:01.440 If I crash accessing this pointer, I'm confident enough to use it without checking. 12:01.650 --> 12:02.250 Okay. 12:02.250 --> 12:04.860 So that takes care of the enemy. 12:04.890 --> 12:09.960 Now for the character, which is going to be a little more complicated, but not much. 12:09.990 --> 12:19.050 Let's find our Aura character class, the CPP version, and we're going to want to override a couple 12:19.050 --> 12:20.220 of functions. 12:20.220 --> 12:28.110 I'll just pull up my slide here again and remind myself that this is the case where concerned with where 12:28.110 --> 12:34.080 the ability system component lives on the player state, we're going to initialize ability actor info 12:34.080 --> 12:39.900 in possessed by for the server and on player state for the client. 12:39.900 --> 12:42.780 So we need to override those functions. 12:42.780 --> 12:51.390 So that means I'm going to hit alt O or control k o on Visual Studio to come into Aura character, and 12:51.390 --> 12:55.080 I'm going to override a couple of virtual functions. 12:55.080 --> 13:04.050 First, we need possessed by so virtual void possessed by and if I right click and go to declaration 13:04.050 --> 13:12.990 or usages, we'll see that this possessed by belongs to the a character class right here and if I go 13:12.990 --> 13:22.110 to character should search for possessed by I can see that it is in the public section. 13:22.200 --> 13:31.380 And by the way notice that we see this comment thing happening here for functions that belong to interfaces. 13:31.380 --> 13:37.020 We're actually seeing the comment for parent classes being referred to as interfaces. 13:37.050 --> 13:38.820 Now, we could do that too, if we want. 13:38.850 --> 13:44.670 In fact, if you want to copy the same sort of comment style, you can do that as well. 13:44.670 --> 13:45.630 It's up to you. 13:45.660 --> 13:49.140 We can say begin interface and end interface. 13:49.410 --> 13:52.680 So if you want to use that comment style, feel free. 13:52.800 --> 14:00.270 But I wanted to see that possessed by is a public function and we're also going to want to override 14:00.300 --> 14:09.980 virtual void on wrap player state and we can go ahead and generate the definitions for both of these 14:09.980 --> 14:11.090 functions. 14:11.730 --> 14:12.900 There they are. 14:13.140 --> 14:21.690 And if we hit shift shift that allows us to search, we can search for on rep player state and we see 14:21.690 --> 14:24.860 that that one belongs to the pawn class. 14:24.870 --> 14:27.660 Here it is on rep player state. 14:27.960 --> 14:33.570 And we see here in the pawn class that this function is also public. 14:33.990 --> 14:38.010 So we'll go ahead and override that one. 14:38.010 --> 14:45.780 Now that we have these two functions, we can do what we need to do, which is call init ability actor 14:45.780 --> 14:46.470 info. 14:46.470 --> 14:49.560 So we'll start with possessed by now. 14:49.560 --> 14:52.260 Remember this one's for the server, so I'm going to make a comment. 14:52.260 --> 15:03.810 So we remember init ability actor info for the server and remember we need to access the player state. 15:03.810 --> 15:12.640 So I need to call get player state and we have a template version of this so we can pass in a or a player 15:12.640 --> 15:17.620 state as the type and that will return the appropriate type. 15:17.650 --> 15:21.520 Now I'm going to make a local or a player state variable. 15:21.520 --> 15:27.580 I'm going to say A or a player state called or a player state. 15:28.690 --> 15:30.790 And I'm going to wrap this in an if statement. 15:30.790 --> 15:39.160 So if that way, if this is valid, which it should be at this point, in fact, it's kind of important. 15:39.160 --> 15:43.450 Let's go ahead and just use an assert instead. 15:43.450 --> 15:45.720 This should not be a null pointer. 15:45.730 --> 15:47.800 We should be pretty confident. 15:47.950 --> 15:56.650 So we'll say check or a player state and then we'll take or a player state and we're going to get the 15:56.650 --> 15:58.600 ability system component from this. 15:58.600 --> 16:02.170 We're going to call get ability system component. 16:02.170 --> 16:09.520 And from that we now have the ability system component we can call init ability actor info and we can 16:09.520 --> 16:13.000 pass in the owner, actor and the avatar actor. 16:13.180 --> 16:17.740 Now in this case, the owner actor is going to be the player state. 16:17.740 --> 16:24.610 So we're going to pass in or a player state for the owner actor and the Avatar actor will be the character 16:24.610 --> 16:26.890 itself that's going to be this. 16:26.980 --> 16:28.510 So that's the difference. 16:28.510 --> 16:33.700 When you have the ask or ability system component on the player state. 16:33.700 --> 16:40.750 But we have to set this here in possessed by because we need to be sure that we have a valid player 16:40.750 --> 16:48.100 controller set already and that our player state is valid and accessible and we can call this function 16:48.100 --> 16:48.370 here. 16:48.370 --> 16:49.720 So that takes care of this. 16:49.720 --> 16:57.790 But remember, we have the player state now that's a good opportunity to set the Aura character's ability 16:57.790 --> 16:59.200 system component pointer. 16:59.200 --> 17:06.280 So we're going to say ability system component equals and we'll take Aura player state and call get 17:06.310 --> 17:07.870 ability system component. 17:07.870 --> 17:11.260 We'll set that and we'll set our attribute set as well. 17:11.260 --> 17:12.880 We'll say attribute set. 17:14.600 --> 17:16.490 Equals or a player state. 17:16.520 --> 17:17.930 Get attribute set. 17:17.930 --> 17:22.100 And now we're starting to see the benefit of having those getter functions. 17:22.400 --> 17:29.750 Okay, so these pointers are set here on the server and we've initialized ability actor info here on 17:29.750 --> 17:30.230 the server. 17:30.230 --> 17:33.620 We're going to want to initialize it for the client as well. 17:33.620 --> 17:40.070 That's why we're doing it in on Rep Player State, which means we're going to do the very same thing 17:40.070 --> 17:40.760 we did here. 17:40.760 --> 17:48.290 We're going to get the player state, check it and call init ability actor info and set these to pointers. 17:48.290 --> 17:53.600 We're going to do the same thing now rather than just repeating myself. 17:53.690 --> 17:57.080 You may have heard of the dry principal dry. 17:57.110 --> 17:58.580 Don't repeat yourself. 17:58.850 --> 18:06.050 Rather than copying several lines of code and pasting them, I would like to instead create a function 18:06.050 --> 18:08.960 that I can reuse in both of these. 18:08.960 --> 18:18.690 So let's go ahead and go to Ora character here and make a private function that we can just call twice. 18:18.690 --> 18:24.900 So I'm going to say void and I'll just call this init ability actor info. 18:26.430 --> 18:28.290 That's really all it's doing. 18:28.290 --> 18:33.900 So let's make a function definition and it's going to be these lines of code here. 18:34.200 --> 18:40.200 So I'm going to go ahead and control X and control V. 18:40.230 --> 18:43.140 Now we have a function that does these things for us. 18:43.140 --> 18:49.500 We can call it here and possessed by and we can call it here and on Player state. 18:49.500 --> 18:58.800 And we'll have a comment here that says init ability actor info for the client and that's it. 18:58.830 --> 19:04.020 Now if you didn't do this refactor into a function, that's totally fine. 19:04.020 --> 19:06.600 It's okay if you repeated yourself not a big deal. 19:06.600 --> 19:10.020 I do recommend making a function, but you don't have to. 19:10.020 --> 19:12.660 And now we've achieved a couple things. 19:12.660 --> 19:16.950 For one, our ability system components know who their owner is. 19:16.980 --> 19:20.880 They know who the owner actor is and they know who the Avatar actor is. 19:20.910 --> 19:27.360 That's going to be very, very useful and convenient as we continue programming in gas throughout this 19:27.360 --> 19:34.260 course, because there will be many, many times when we need to access those owners in our abilities 19:34.260 --> 19:37.230 in our various gas classes. 19:37.230 --> 19:40.530 So this is a very important and crucial step. 19:40.710 --> 19:47.340 And before we end the video, I'm going to bring your attention back to the replication mode. 19:47.340 --> 19:54.420 Again, remember, we set our ability system component for the player controlled character to mixed 19:54.420 --> 19:55.500 replication mode. 19:55.500 --> 19:59.790 And it's important to know a couple of details when you do this. 20:00.680 --> 20:02.420 For mixed replication mode. 20:02.450 --> 20:08.250 It's important to know that the owner actors, owner must be the controller. 20:08.270 --> 20:15.080 Now, in our case the owner actor for our ability system component, at least for the player controlled 20:15.080 --> 20:19.070 character that has mixed replication mode is the player state. 20:19.070 --> 20:24.410 That's who we set as the owner actor in an ability actor info. 20:24.440 --> 20:29.720 Now we don't need to set the player state's owner to the controller because that's what happens. 20:29.720 --> 20:30.920 By default. 20:30.920 --> 20:36.620 The player state's owner is automatically set to the controller, so we don't really need to do anything. 20:36.650 --> 20:40.780 Similarly for pawns this is automatically set in possessed by. 20:40.790 --> 20:48.470 So if the owner actor for the ability system component is the pawn well in possessed by the pawns owner 20:48.470 --> 20:50.210 will be set to the controller. 20:50.540 --> 20:57.680 But if your owner actor is not the player state and you're using mixed replication mode, you must call 20:57.680 --> 21:03.580 set owner on the owner actor and set its owner to the controller. 21:03.600 --> 21:10.410 So even though we don't need to worry about it because our owner actor is the player state and the player 21:10.410 --> 21:13.710 state's owner is already set to the controller. 21:13.740 --> 21:20.640 You need to know this because your owner actor may be some class that does not automatically get its 21:20.640 --> 21:23.070 owner set to the controller. 21:23.070 --> 21:27.870 In that case, you're going to want to make sure that it is if applicable. 21:28.080 --> 21:32.730 You might have an ability system component on some actor that doesn't have a controller. 21:32.730 --> 21:35.770 In that case, that's fine, don't worry about it. 21:35.790 --> 21:42.120 But for mixed replication mode, the owner actor's owner must be the controller. 21:42.120 --> 21:43.700 So keep this in mind. 21:43.710 --> 21:49.620 This is not something that you'll worry about in this course, in this project, but keep it in mind 21:49.620 --> 21:52.860 for your future gas projects where things might be different. 21:53.220 --> 21:55.510 So just something you might want to jot down. 21:55.530 --> 21:56.130 Okay. 21:56.130 --> 21:57.180 Excellent job. 21:57.210 --> 22:00.720 We'll continue with this in the next video.