WEBVTT 00:06.900 --> 00:08.070 Welcome back. 00:08.190 --> 00:14.760 So our attribute menu is looking pretty good so far, but we do need a way to broadcast data to the 00:14.760 --> 00:15.270 menu. 00:15.270 --> 00:18.570 And we know that we have a few steps in the way of that. 00:18.600 --> 00:24.600 One of those steps is we need to have a gameplay tag associated with all of our attributes. 00:24.600 --> 00:27.060 Each one gets its own gameplay tag. 00:27.360 --> 00:31.490 Now we've seen a couple of ways to add gameplay tags to our project. 00:31.500 --> 00:38.130 If we go to project settings and gameplay tags, we've seen that we can add tags directly from within 00:38.130 --> 00:39.470 the project settings. 00:39.480 --> 00:46.170 We can also add them from a source, which is a config file and we can add them from data tables that 00:46.170 --> 00:48.180 use the gameplay tag table row. 00:48.210 --> 00:50.860 We've done that for our primary attributes. 00:50.880 --> 00:57.630 Now the problem with these methods is when we need to use those tags in C plus plus. 00:57.780 --> 01:02.620 The way to do so is by the use of request gameplay tag. 01:02.640 --> 01:08.370 Now we do this in our widget controller class overlay widget controller. 01:08.380 --> 01:12.370 We're using request gameplay tag using message. 01:12.370 --> 01:18.490 So this is for part of a gameplay tag and this is a pretty good use case for request gameplay tag. 01:18.490 --> 01:22.810 But we don't want to have to do this every time we need a gameplay tag. 01:22.810 --> 01:29.710 We want to be able to use variables and have some kind of central source for variables for all the gameplay 01:29.710 --> 01:31.060 tags in our project. 01:31.060 --> 01:36.190 And then we don't have to type out these strings and be worried about typos and things like that. 01:36.190 --> 01:42.670 So we're going to create a centralized location for the gameplay tags, at least those that we need 01:42.670 --> 01:45.220 to use in the C plus plus domain. 01:45.220 --> 01:49.450 And those are going to include our attribute gameplay tags. 01:49.570 --> 01:55.990 So in order to store these gameplay tags in a centralized location, we're going to create a C plus 01:55.990 --> 01:57.880 plus class to store them. 01:57.880 --> 02:05.800 And this is going to be a C plus plus class or struct that we will only have one of in our project. 02:05.830 --> 02:09.490 We're going to enforce that by using the singleton pattern. 02:09.490 --> 02:16.900 So let's go into our C plus plus classes ora folder and we'll go into public. 02:16.900 --> 02:24.100 And I'd like our class to be right here, sort of at the project level so we can access it quite easily 02:24.100 --> 02:25.240 from any class. 02:25.240 --> 02:30.640 So I'm going to right click new C plus plus class, and this is not going to be based on any of the 02:30.640 --> 02:31.750 engine classes. 02:31.750 --> 02:35.830 It's going to be none, an empty C plus plus class. 02:35.830 --> 02:44.290 So we're going to click next and we can let this go into Ora slash public and Ora slash private respectively. 02:44.410 --> 02:47.590 And this will be our singleton for gameplay tags. 02:47.860 --> 02:56.200 Now I'm going to call this ora gameplay tags because the project is Ora, so this will be the tags for 02:56.200 --> 02:57.310 this project. 02:57.310 --> 02:59.860 So let's go ahead and create the class. 02:59.860 --> 03:07.450 I'm going to close out of the editor and go into writer and here I see my new Ora gameplay tags. 03:07.480 --> 03:16.540 It's created a new class for me and included core minimal and alt O is going to bring up my class CPP 03:16.570 --> 03:17.260 file. 03:17.590 --> 03:20.080 Now we can make this a class or a struct. 03:20.080 --> 03:20.950 It doesn't matter. 03:20.950 --> 03:25.630 I'm going to make this a struct as this will be a pretty simple type for us. 03:25.630 --> 03:33.400 So I'm actually going to delete the class declaration and delete the constructor and destructors and 03:33.400 --> 03:41.350 instead I'm going to declare a struct and this will be my f ora gameplay tags. 03:42.010 --> 03:48.280 So let's make that class body and structs have a public body by default. 03:48.400 --> 03:56.050 Even so, I'm going to explicitly make a public a protected and a private section. 03:57.280 --> 03:59.440 Now this is going to be a singleton. 03:59.440 --> 04:02.440 In fact, I'm going to go ahead and put a comment here. 04:02.440 --> 04:13.180 We're going to say ora gameplay tags, and we'll also say that this is a singleton containing native 04:13.180 --> 04:21.460 gameplay tags, native in a sense that they're created from within C plus plus and available in C plus 04:21.460 --> 04:22.000 plus. 04:22.030 --> 04:25.330 Now these will be available in the editor in Blueprint as well. 04:25.540 --> 04:32.050 Now we're going to be using the gameplay tag type and that means we need to include where that type 04:32.050 --> 04:33.010 is defined. 04:33.010 --> 04:38.800 So we're going to add the include here and that's in gameplay tag container dot H, We're going to make 04:38.800 --> 04:46.330 sure to include that and here in F or a gameplay tags, because this is a singleton, we're going to 04:46.330 --> 04:49.600 design this in a specific way with a singleton. 04:49.630 --> 04:56.860 What you do is you create a static getter function so you don't need an instance of the class to exist 04:56.860 --> 04:59.770 to be able to call one of its static functions. 04:59.890 --> 05:06.550 So if we make a static function, I'll make it const and its return type will be F or a game. 05:06.620 --> 05:08.990 Play tags and it'll return a reference. 05:09.010 --> 05:14.770 We want to return a reference to the one and only instance of or a gameplay tags that will exist in 05:14.770 --> 05:15.520 the game. 05:15.520 --> 05:18.670 And we call this get and get is simple. 05:18.670 --> 05:20.320 It returns well. 05:20.320 --> 05:23.860 It's going to return the one and only instance that exists. 05:23.980 --> 05:25.720 Now what is that instance? 05:25.720 --> 05:32.590 Well, it's going to be a static variable on this class, so the class itself will have a variable to 05:32.590 --> 05:35.080 store the one and only instance of itself. 05:35.080 --> 05:37.330 So here's how we'll do it. 05:37.540 --> 05:47.380 We'll make a private static variable of type F or a gameplay tags called gameplay tags, and the static 05:47.380 --> 05:50.770 function gets will return gameplay tags. 05:51.550 --> 05:58.780 So once one of these is constructed, then we can just call the static function, get to get the one 05:58.780 --> 06:00.880 and only instance of gameplay tags. 06:00.910 --> 06:09.140 Now, for a static variable like this, we need to go into the CPP file and explicitly declare the type 06:09.140 --> 06:09.530 here. 06:09.530 --> 06:15.920 So we say f or a gameplay tags and then we declare the variable fully qualified with F or a gameplay 06:15.920 --> 06:16.730 tags. 06:16.760 --> 06:19.820 Gameplay tags like so. 06:19.910 --> 06:26.060 So what we're going to do here is we're going to want a public function to initialize our tags. 06:26.060 --> 06:30.050 We want to be able to create those native gameplay tags. 06:30.290 --> 06:34.220 So we'll create a function here that will also be static. 06:34.310 --> 06:41.090 It's a void function and we'll call this initialize native gameplay tags. 06:42.670 --> 06:49.510 So again, a static function that can be called without one of these or a gameplay tag instances even 06:49.510 --> 06:52.170 in existence because it's static, right? 06:52.180 --> 06:58.840 Let's generate the definition and what are we going to do in initialize native gameplay tags? 06:58.840 --> 07:02.590 Well, this is where we're going to kick off initializing gameplay tags. 07:02.950 --> 07:04.570 So here's how we can do it. 07:04.600 --> 07:08.080 We can get the gameplay tag manager. 07:08.080 --> 07:13.120 Remember when we create a gameplay tag, it's registered with the gameplay tag manager. 07:13.150 --> 07:20.770 This is a object in our project there's only one of them and it manages the gameplay tags and we can 07:20.770 --> 07:25.750 also use it to add gameplay tags even natively here in C plus plus. 07:25.750 --> 07:27.370 And that's how we're going to do it. 07:27.370 --> 07:32.800 So we need to access that type the gameplay tag manager, we're going to include that, its gameplay 07:32.830 --> 07:40.840 tag manager dot h and we're going to get you gameplay tag manager and we're going to call a static function 07:40.840 --> 07:43.580 called get interesting, right? 07:43.610 --> 07:48.440 Get a static function that returns the one and only gameplay tag manager. 07:48.440 --> 07:52.520 That's the pattern we're using with our aura gameplay tags here. 07:52.520 --> 08:01.280 So we get that, we get the gameplay tags manager and we can use functions on it such as add native 08:01.280 --> 08:02.300 gameplay tag. 08:02.300 --> 08:09.560 Now add native gameplay tag requires the tag name and it also has a tag dev comment. 08:09.560 --> 08:15.500 Just like when we create gameplay tags in the editor we specify the name of the tag and then we specify 08:15.500 --> 08:18.320 some kind of comment that's optional. 08:18.320 --> 08:18.590 Right? 08:18.590 --> 08:21.260 It could be empty if we don't want to add that. 08:21.260 --> 08:24.290 So we're going to define a native gameplay tag. 08:24.290 --> 08:27.620 Let's start with some of our secondary attributes, shall we? 08:27.650 --> 08:37.670 We'll make an F name as this requires an F name and we'll call this attributes dot secondary dot armor. 08:38.000 --> 08:44.510 And then our next input is an F string and the f string is the comment. 08:44.540 --> 08:46.910 Now for the F string for armor. 08:46.940 --> 08:50.720 This is of course optional, but we'll go ahead and add the comment. 08:50.720 --> 08:58.850 We'll say reduces damage taken, improves blockchains like so. 08:58.850 --> 09:02.210 And this is how we can declare native gameplay tags. 09:02.210 --> 09:05.000 We do it through the gameplay tag Manager. 09:05.120 --> 09:11.750 Okay, so initializing native gameplay tags is just doing this, creating the gameplay tag. 09:11.750 --> 09:19.010 And now we have our gameplay tags, a singleton that we can always get with the get function and we've 09:19.010 --> 09:22.730 created our static gameplay tags instance here. 09:22.730 --> 09:25.340 So we have basically a global singleton. 09:25.370 --> 09:32.630 Now the question that's going to pop up in your mind is at what point in our project should we call 09:32.630 --> 09:34.730 this function to initialize the tags? 09:34.730 --> 09:42.590 Well, probably early on, right, as soon as we can before any of those tags are attempted to be used. 09:42.590 --> 09:47.990 So we're going to learn how to do that by creating our very own asset manager and we'll learn what that 09:47.990 --> 09:49.790 is in the next video. 09:49.970 --> 09:52.130 So great job and I'll see you soon.