WEBVTT 00:06.890 --> 00:08.060 Welcome back. 00:08.180 --> 00:15.890 Now we know how to create an instant gameplay effect, and applying that gameplay effect is relatively 00:15.890 --> 00:23.150 simple, and we applied it using a blueprint callable function which we're calling here in response 00:23.150 --> 00:24.710 to an overlap. 00:24.980 --> 00:33.500 Now before we move on to different duration types for gameplay effects, we should visit how to apply 00:33.500 --> 00:40.520 these gameplay effects directly here in Blueprint without having to call a blueprint callable Cplusplus 00:40.520 --> 00:48.680 function and our cplusplus function here in Aura actor involves getting the ability system component 00:48.680 --> 00:57.470 for the target simply so we can use it to make an effect context and apply a gameplay effect after making 00:57.470 --> 00:57.980 an effect. 00:57.980 --> 00:58.850 Spec. 00:59.090 --> 01:02.870 This is actually quite simple to do here in blueprint as well. 01:02.870 --> 01:10.050 We can take our other actor and we can call get ability system component and if we hover over this we 01:10.050 --> 01:17.880 see target is ability system, blueprint library and that's the function we ended up calling here you 01:17.880 --> 01:22.680 ability system blueprint library get ability system component which takes a target actor. 01:22.710 --> 01:28.470 Here we have the input actor and the return value is the ability system component. 01:28.560 --> 01:35.790 Now once we've gotten that ability system component, we take it and make an effect context with make 01:35.820 --> 01:37.050 effect context. 01:37.080 --> 01:38.790 We can do that here in blueprint. 01:38.820 --> 01:44.130 We can drag off of the return value and type make effect context. 01:45.220 --> 01:51.350 And this function returns a gameplay effect context handle structure. 01:51.370 --> 01:59.890 Just like make effect context here in c plus plus returns a gameplay effect context handle struct same 01:59.890 --> 02:00.460 thing. 02:01.020 --> 02:05.790 Now here in C plus plus we're calling this Add source object function. 02:05.940 --> 02:13.590 Now, if we go to the definition of this, we'll see here that it exists in gameplay effect types and 02:13.590 --> 02:19.890 it's right here inside of scrolling up our gameplay effect context handle. 02:20.340 --> 02:26.610 But we see that this function is not blueprint callable, so we can't call this from blueprint. 02:26.790 --> 02:33.090 We also have get source object which is also not blueprint callable, but here in Blueprint, if we 02:33.090 --> 02:37.050 type in source object, we see that we have a get source object. 02:37.320 --> 02:41.030 So how can we call this in blueprint if it's not blueprint callable? 02:41.040 --> 02:47.910 Well, this is not a function on this struct, it's a function on ability system blueprint library. 02:47.910 --> 02:54.960 So these static libraries are a great way to expose to blueprint certain things that you can only do 02:54.990 --> 02:55.920 in C plus plus. 02:55.920 --> 03:03.100 And later on in the course we'll be making our own Blueprint library that we can use to expose certain 03:03.100 --> 03:06.270 utilities to the blueprint side like this. 03:06.280 --> 03:13.600 So while we can't call Add source object, we could make a static function library, a blueprint library 03:13.600 --> 03:21.280 of our own, and create a static function that could take in an effect context and call a function such 03:21.280 --> 03:23.980 as add source object, for example. 03:23.980 --> 03:31.180 So that's one of the limitations of doing this from blueprint, but closing gameplay effect types and 03:31.180 --> 03:34.090 going back into aura effect. 03:34.090 --> 03:39.790 Actor The next thing we did was we made an outgoing spec this gameplay effect spec handle. 03:39.790 --> 03:42.580 This is a function on the ability system component. 03:42.910 --> 03:51.610 So from here in Blueprint we could drag off and type make outgoing spec and notice that make outgoing 03:51.640 --> 03:58.510 spec requires a gameplay effect class which we have one here we have instant gameplay effect class. 03:58.540 --> 04:02.650 If I duplicate that node and plug it in, that will satisfy it. 04:02.680 --> 04:08.770 We can also set the level in C plus plus we set it to one and it takes a gameplay effect. 04:08.770 --> 04:10.960 Context handle structure. 04:10.960 --> 04:13.780 That's what make effect context returns. 04:13.780 --> 04:16.480 So we could simply plug that straight in there. 04:16.480 --> 04:19.090 And we now have an outgoing spec. 04:19.270 --> 04:26.320 Now the last thing we did here in C plus plus was call apply gameplay effect spec to self on the ability 04:26.320 --> 04:27.550 system component. 04:27.580 --> 04:36.400 Here in blueprints we can take our ability system component and call apply gameplay effect spec to self. 04:36.400 --> 04:43.750 We see that there are other options here as well, but if we choose apply gameplay effect spec not effect 04:43.750 --> 04:48.730 but effect spec to self, then we see that we can plug in a spec handle. 04:48.730 --> 04:51.760 That's the return value from make outgoing spec. 04:51.760 --> 04:58.240 So as you can see this looks a little bit cleaner in blueprint as here in C plus plus we had to get 04:58.240 --> 05:03.250 the effect spec handle and get the data which is a pointer wrapper. 05:03.250 --> 05:09.520 We had to get the raw pointer and dereference it in order to pass in that object. 05:09.520 --> 05:12.130 Here in Blueprint, we don't have to do any of that. 05:12.160 --> 05:19.480 We just call a handful of functions that are exposed to blueprint and it's a little bit easier, a little 05:19.480 --> 05:22.480 quicker to do, but you can do it either way. 05:22.480 --> 05:25.660 And we've seen that on the C plus plus side. 05:25.690 --> 05:31.870 We do have more options as not everything in C plus plus is exposed to blueprint. 05:32.330 --> 05:38.420 And another benefit is we did all this work in C plus plus right here in our blueprint callable function. 05:38.420 --> 05:45.860 So the end result is that our blueprint is cleaner as we only have a single node and as things get more 05:45.860 --> 05:49.700 complex, we'll be able to implement those in C plus plus. 05:49.700 --> 05:58.430 But really using one versus the other is really not going to result in, say, a significant performance 05:58.430 --> 06:02.300 difference, at least in this case, as we're doing simple things here. 06:02.300 --> 06:09.470 But to make sure that this works, we could bypass our blueprint callable node and we can simply call 06:09.470 --> 06:17.030 apply gameplay effect spec to self and simply destroy the actor after that, like so. 06:17.030 --> 06:24.350 And if we wanted to make sure that this only works for an actor that has an ability system component 06:24.350 --> 06:31.040 here we can add an is valid to the ability system component we can say is valid here. 06:31.940 --> 06:37.850 Use the one with the question mark and run it through the is valid node first like so. 06:38.030 --> 06:41.540 And we can tidy this up just a little bit. 06:43.130 --> 06:46.270 This does get a little bit messy in blueprint. 06:46.280 --> 06:54.350 Another reason to opt for the C plus plus option as blueprints can get a bit out of hand. 06:54.500 --> 07:01.100 And ideally this could be collapsed into a function of its own and cleaned up even further. 07:01.100 --> 07:05.510 But let's just make sure that we can prove to ourselves that the blueprint option works. 07:05.540 --> 07:08.960 Let's go and pick up the health potion. 07:08.960 --> 07:14.540 That's the one that we changed and we see that it works and we're not using the C plus plus function 07:14.540 --> 07:15.170 anymore. 07:15.170 --> 07:16.790 Now we're using the blueprint option. 07:16.790 --> 07:22.610 So two options for you, and I'll just leave those nodes there for now. 07:22.610 --> 07:25.280 But we're using our C plus plus function. 07:25.940 --> 07:27.230 Okay, great. 07:28.020 --> 07:29.790 Just moving that out of the way. 07:30.300 --> 07:36.510 Now for the topic of this lecture, and I'll just vocalize it. 07:36.510 --> 07:40.830 I hooked up, destroy actor and everything's back to how it was there. 07:40.860 --> 07:48.660 Now the topic for this lecture is the different types of duration policies for our gameplay effects. 07:48.660 --> 07:53.580 We have a G potion heal, which is an instant gameplay effect. 07:53.580 --> 08:01.530 Our potion mana is also an instant gameplay effect, but instant is just one of three choices. 08:01.530 --> 08:03.990 We also have infinite and has duration. 08:03.990 --> 08:10.670 In this video I'd like to discuss has duration and see how the has duration type works. 08:10.680 --> 08:16.770 So to showcase the has duration gameplay effect, I'd like to make a new one. 08:16.770 --> 08:21.000 I'm going to right click here and create a new blueprint class. 08:21.000 --> 08:23.370 I'm going to search for gameplay effect. 08:23.910 --> 08:27.450 Choose that class and call this one g. 08:27.480 --> 08:31.360 Underscore core and this will be the duration based heal. 08:31.370 --> 08:35.150 So I think I'd like to use something other than a health potion. 08:35.180 --> 08:44.240 The assets folder in this startup project has a crystal, so I'm going to say crystal heal and we can 08:44.240 --> 08:47.330 make maybe a healing crystal, for example. 08:47.420 --> 08:49.820 So I'm going to open up crystal Heal. 08:49.940 --> 08:57.800 And here in the Details panel, I'm going to scroll down to the duration policy and change it to has 08:57.800 --> 08:58.750 duration. 08:58.760 --> 09:04.850 Now that it's has duration, we need to specify the duration magnitude. 09:05.060 --> 09:12.280 Essentially, how many seconds is this effect going to be applied before it removes itself? 09:12.290 --> 09:19.400 So for the duration magnitude, we have scalable float attribute based custom calculation class and 09:19.400 --> 09:20.390 set by caller. 09:20.390 --> 09:28.420 So far we only have experience with scalable float which as we know we can hardcode a value in and we 09:28.420 --> 09:30.430 can also scale it by a table. 09:30.430 --> 09:32.800 Now we haven't created a table yet. 09:32.830 --> 09:35.670 Don't worry, we'll get to all these features, we're going to cover them all. 09:35.680 --> 09:41.950 But I'm going to set a scalable float magnitude of two, and this is in seconds. 09:41.950 --> 09:48.010 So this effect will be applied for two seconds, after which it will remove itself. 09:48.400 --> 09:52.720 And if we have any modifiers here, those modifiers will be undone. 09:52.720 --> 10:00.070 So, for example, if I want to modify one of my attributes, I can add a modifier with the plus icon 10:00.070 --> 10:01.930 and I can select the attribute. 10:01.930 --> 10:04.300 Let's say I want to select Max Health. 10:04.540 --> 10:12.970 And for Max health, I'd like to add to it and for the modifier magnitude expanding that, I'm going 10:12.970 --> 10:17.920 to set the scalable float magnitude to 100. 10:18.130 --> 10:22.420 So in other words, the max health will be added to by 100. 10:22.450 --> 10:29.530 Now the max health is already starting at 100, which means it will be now 200 for two seconds. 10:29.650 --> 10:35.860 And the result of that is we should see the health globe actually appear to go down because the amount 10:35.860 --> 10:37.810 of health, the current health value. 10:37.840 --> 10:39.670 Health is going to be the same. 10:39.670 --> 10:45.760 But, Max, health will be larger, which means the percentage of health will be the same value divided 10:45.760 --> 10:48.760 by an even larger value for max health. 10:48.910 --> 10:52.630 So we should actually see that health globe go down. 10:52.630 --> 10:54.580 It'll look like you have less health. 10:54.580 --> 10:58.270 You really have the same amount of health, but the max health has changed. 10:58.270 --> 11:01.960 So we have this crystal heal, right? 11:01.960 --> 11:05.710 And we want to apply this duration based effect. 11:06.040 --> 11:13.840 And we can easily do that by creating a new blueprint based on our aura effect actor and setting its 11:13.870 --> 11:14.770 effect. 11:14.770 --> 11:18.580 But we called our effect instant gameplay effect class. 11:18.580 --> 11:24.430 We should add a new variable for a gameplay effect that has a duration. 11:24.430 --> 11:27.160 So what I'm going to do is I'm going to save all. 11:27.160 --> 11:33.040 I'm going to close the editor and we're going to add one more variable to aura effect. 11:33.040 --> 11:35.560 Actor We'll go ahead and rearrange these here. 11:35.560 --> 11:41.950 I'm going to close out of the files I'm not using and just under instant gameplay effect class, I'm 11:41.950 --> 11:52.330 going to add another subclass of holding a gameplay effect and this one will be called Duration Gameplay 11:52.330 --> 11:53.470 Effect class. 11:53.470 --> 11:57.240 So we'll have a different variable here. 11:57.250 --> 12:06.250 So what we can do is now we can make a blueprint for the health crystal that actually applies the duration 12:06.250 --> 12:09.190 gameplay effect and not the instant gameplay effect. 12:09.190 --> 12:10.720 So that's what we'd like to do. 12:11.360 --> 12:14.030 And that's going to be your quest. 12:14.420 --> 12:17.990 I'd like you to create the health crystal blueprint. 12:17.990 --> 12:21.530 You can call it BP health crystal, if you like. 12:21.530 --> 12:29.330 And you're going to set that duration based gameplay effect on this blueprint and then go ahead and 12:29.330 --> 12:30.470 apply the effect. 12:30.470 --> 12:36.770 You can use our blueprint callable function we created or you can get some practice doing it all in 12:36.770 --> 12:37.490 blueprint. 12:37.520 --> 12:39.650 Go ahead and make that choice. 12:39.650 --> 12:43.130 So pause the video and conquer this quest now. 12:46.380 --> 12:53.520 Okay, so now that I have my duration gameplay effect class, I'm going to go ahead and run this in 12:53.520 --> 12:57.420 debug mode so I can make the blueprint and test it out. 12:58.420 --> 12:59.050 All right. 12:59.050 --> 13:02.800 So back here in the editor, I'm going to make a new blueprint. 13:02.830 --> 13:07.780 Right click Blueprint class, and I'm going to base it on aura effect actor. 13:09.020 --> 13:10.160 Choose that. 13:10.880 --> 13:16.750 And I'm here in the potion folder, and this is a crystal technically, but that's okay. 13:16.760 --> 13:18.980 I'm just going to keep it here in the potion folder. 13:18.980 --> 13:21.800 It's basically another type of potion. 13:21.800 --> 13:24.680 And I'm going to call this health crystal. 13:25.130 --> 13:33.200 I'm going to open health crystal and I'm going to need a mesh and some kind of overlap volume. 13:33.200 --> 13:34.190 So I'll do that. 13:34.190 --> 13:38.360 First, I'll select the root component, create the static mesh. 13:38.810 --> 13:40.550 Simply call this mesh. 13:40.880 --> 13:46.670 Actually, I'll call this crystal mesh and I'll search for Crystal. 13:47.630 --> 13:52.430 And it looks like we have a static mesh called health Crystal, and it's quite large, so I'm going 13:52.430 --> 14:01.820 to scale it on down by about 0.2 in each dimension and I'll add a collision volume. 14:02.150 --> 14:05.020 And for this one, since I can, why not? 14:05.030 --> 14:07.370 I'll go ahead and add a capsule. 14:08.120 --> 14:10.770 So I'm going to get that capsule in here. 14:10.770 --> 14:19.380 I'll just leave it named capsule and I can adjust its size a little bit like so. 14:19.590 --> 14:26.460 And the center of my crystal isn't perfect, so I'm going to take that crystal mesh and just move it 14:26.460 --> 14:29.550 a bit so it's centered without snapping on. 14:30.690 --> 14:31.350 Like. 14:31.350 --> 14:36.900 So if I wanted to be precise, I could go from perspective to left. 14:38.820 --> 14:42.240 And move it more precisely. 14:42.390 --> 14:44.490 And go to right. 14:44.520 --> 14:46.500 And move it more precisely. 14:47.550 --> 14:48.450 All right. 14:48.450 --> 14:49.440 Looking good. 14:49.440 --> 14:52.290 I'm going to make sure my crystal mesh has no collision. 14:53.400 --> 14:58.290 Some of those things you typically do for things like these pickups. 14:58.290 --> 15:04.440 I'm going to go to my capsule collision settings here and it's set to overlap all dynamic. 15:04.440 --> 15:05.520 I'll just leave it at that. 15:05.520 --> 15:06.720 That's fine. 15:06.730 --> 15:08.520 It's set to generate overlap events. 15:08.520 --> 15:09.420 Perfect. 15:09.420 --> 15:14.490 And I'll go to Health Crystal Self and search for duration. 15:14.490 --> 15:17.010 And here's duration gameplay effect class. 15:17.010 --> 15:19.860 I'm going to choose my crystal heal. 15:20.490 --> 15:26.760 And now we have that set and instant gameplay effect class I'm going to leave on set and in the event 15:26.760 --> 15:33.360 graph I'm going to take my capsule and use on component began overlap. 15:34.330 --> 15:41.200 And I can either use my blueprint callable function to apply the effect or I can do everything in blueprint. 15:41.200 --> 15:49.960 I'm going to use my apply effect to target a blueprint callable function and I will plug in other actor 15:49.960 --> 16:00.610 as the target actor and use my duration gameplay effect class as the gameplay effect and I'll go ahead 16:00.610 --> 16:01.480 and destroy. 16:01.510 --> 16:05.020 So destroy actor after this. 16:08.530 --> 16:11.270 All right, Now all that's left is to test it out. 16:11.290 --> 16:17.800 I'm going to compile and save and drag out a BP health crystal blueprint. 16:18.370 --> 16:19.750 I'll bring it out here. 16:19.900 --> 16:23.680 I'm going to save all and play test. 16:23.830 --> 16:30.280 Now, we should see because our health will be the same value, but our max health will be twice as 16:30.280 --> 16:30.890 large. 16:30.910 --> 16:33.600 This should go down and I can even show debug. 16:33.610 --> 16:42.730 Remember to click in the viewport before hitting tilde key show debug ability system and I see health 16:42.730 --> 16:44.770 is 50 max health is 100. 16:44.800 --> 16:47.290 Let's pick up that healing crystal. 16:47.530 --> 16:51.640 And now we see max health is 200, but now it's back to 100. 16:51.670 --> 16:52.150 Why? 16:52.180 --> 16:57.520 Because this is a duration based gameplay effect and we set the duration to two seconds. 16:57.550 --> 17:01.270 Let's see that again because two seconds isn't a long time. 17:01.270 --> 17:06.670 Here's the health goes down, but two seconds later it comes back up. 17:06.670 --> 17:13.310 Now, this is extremely useful because without that built in capability of gameplay effects, we'd have 17:13.310 --> 17:18.500 to create our own timers and create callbacks for when the timers finish. 17:18.500 --> 17:20.630 And it's all a lot more work. 17:20.630 --> 17:27.560 Whereas all we needed to do was make a gameplay effect and just set its duration and the duration magnitude, 17:27.560 --> 17:29.000 and it was quite easy. 17:29.030 --> 17:35.480 Now setting our max health to what it was, plus 100 for two seconds and then setting it back to what 17:35.480 --> 17:36.770 it was before. 17:36.800 --> 17:38.030 That's kind of silly. 17:38.030 --> 17:44.450 It's not really a gameplay mechanic that you would think up and decide to implement in a game. 17:44.450 --> 17:51.650 This was just for demonstrating how a duration based gameplay effect works, but in the videos to come 17:51.650 --> 17:54.200 we're going to see how we can have a gameplay effect. 17:54.230 --> 17:56.690 Apply changes periodically. 17:56.690 --> 18:04.250 In other words, every so often apply some kind of change, such as healing over time and things like 18:04.250 --> 18:04.580 that. 18:04.580 --> 18:07.610 And those are the type of things that you would see in a game. 18:07.610 --> 18:09.170 So great job. 18:09.170 --> 18:12.500 This video We learned about duration based gameplay effects. 18:12.500 --> 18:18.110 We're still going to make this aura effect actor a little more flexible, so we'll do that in the videos 18:18.110 --> 18:18.830 to come. 18:18.860 --> 18:19.670 Great job. 18:19.670 --> 18:20.780 I'll see you soon.