WEBVTT 00:06.810 --> 00:07.860 Welcome back. 00:07.890 --> 00:15.120 Now we'd like a behavior tree specific to the shaman, but for the most part, I want things to be pretty 00:15.120 --> 00:16.350 much the same. 00:16.350 --> 00:18.630 We're just going to change a couple of things. 00:18.630 --> 00:22.800 So the first thing I'm going to do is duplicate this enemy behavior tree. 00:22.830 --> 00:28.500 I'm just going to right click on it and choose duplicate and I'm going to call this BT Behavior tree 00:28.500 --> 00:30.180 underscore Shaman. 00:30.180 --> 00:32.580 Really, it doesn't have to be that specific. 00:32.580 --> 00:39.870 We can make it elementalist as we could have other enemies that are elementalists that are not shamans. 00:39.870 --> 00:45.990 So now that we have this behavior tree, I'd like to go into my shaman and change the behavior tree 00:45.990 --> 00:50.210 to the Elementalist version and just make sure that this still works. 00:50.220 --> 00:56.160 Now all it's doing is trying to activate abilities with the attack tag, and our shaman doesn't have 00:56.160 --> 00:57.720 an ability with the attack tag. 00:57.720 --> 01:00.000 It just has the summon ability. 01:00.000 --> 01:03.420 So I'd like it to have that ability so we can see it attack. 01:03.420 --> 01:09.880 So we're going to go into blueprints, ability system data, the character class info and go into our 01:09.880 --> 01:17.140 elementalist and make sure that it's startup abilities not only has summoned ability but also the attack 01:17.170 --> 01:17.770 ability. 01:17.770 --> 01:23.230 So g A and this is going to be the actually firebolt ability. 01:23.230 --> 01:27.550 But we need enemy firebolt the one specific to enemies, right? 01:27.550 --> 01:30.610 So now it has summon and enemy firebolt. 01:30.610 --> 01:38.590 And since it's using the new enemy behavior tree, which is just a duplicate of the old behavior tree, 01:38.620 --> 01:43.360 we should see the same behavior that we saw before we made our summon ability. 01:43.360 --> 01:46.960 In other words, our shaman should launch fireballs at us. 01:46.960 --> 01:51.430 So let's save all and press play and see if that's the behavior we get. 01:51.430 --> 01:52.690 And we do. 01:53.190 --> 01:55.170 Now we have an issue here. 01:55.500 --> 01:59.880 It looks like we're getting a premature explosion. 02:01.610 --> 02:05.190 It looks like we're exploding a little early here. 02:06.060 --> 02:09.080 So let's go ahead and see what it is we're hitting. 02:09.210 --> 02:16.320 I'm going to go into our actor folder and open ora projectile and we'll just place a breakpoint right 02:16.320 --> 02:18.420 away in on sphere Overlap. 02:18.450 --> 02:20.690 Let's see what it is that we're hitting. 02:20.700 --> 02:22.200 I'm going to press play. 02:23.180 --> 02:28.430 And right away we can check other actor and I see that it's one of the tiles. 02:28.430 --> 02:35.000 So we might actually be spawning that projectile a little bit too close to the ground. 02:35.180 --> 02:41.300 So I'm going to remove that breakpoint and resume and let's see if we can tweak things a little bit 02:41.300 --> 02:43.280 so that we don't get that overlap. 02:48.210 --> 02:57.800 I'm going to open Blueprint's ability system or a abilities fire and Firebolt and open up Firebolt. 02:57.810 --> 03:00.210 Let's take a look at its sphere. 03:00.360 --> 03:02.370 It's a little bit large. 03:02.370 --> 03:08.670 I like that it's large, but we can make it a little bit smaller and see if that fixes the problem. 03:08.970 --> 03:10.530 Let's just see. 03:13.580 --> 03:15.740 And it looks like that fixes the problem. 03:15.740 --> 03:22.970 And even though it's a little bit easier to miss, I think that that's okay. 03:23.720 --> 03:30.020 Our little shaman guy is just so close to the ground, it's hard to have such a large sphere there. 03:30.790 --> 03:37.300 An alternative is to disable collision on the sphere for the first, say, 0.5 seconds or so. 03:37.330 --> 03:44.200 That way it kind of passes through everything for the first bit of time before moving on. 03:44.230 --> 03:46.630 That might be something we could try. 03:46.720 --> 03:51.230 We could go to our event graph and an event begin play. 03:51.250 --> 03:56.740 We could set a timer of sorts and enable collision then. 03:56.740 --> 04:01.570 And then our sphere could be set to no collision from the start. 04:01.600 --> 04:03.120 Let's see if that works. 04:03.130 --> 04:06.340 Let's go to collision enabled. 04:06.370 --> 04:09.250 We want it set to query only shortly after spawning. 04:09.250 --> 04:09.790 Right. 04:09.790 --> 04:16.880 But we can set it to no collision first and set it to query only here after a short delay. 04:16.900 --> 04:19.030 So we could say delay. 04:20.200 --> 04:22.750 We'll leave it at 0.2, maybe 0.5. 04:23.020 --> 04:27.250 And then we can set the collision enabled for the sphere. 04:27.400 --> 04:28.420 So set. 04:28.420 --> 04:31.390 Collision enabled. 04:31.420 --> 04:33.640 We can set it to query only. 04:34.650 --> 04:40.800 And I'd like to see exactly where the fireball is in relation to its spawn point at this point in time. 04:40.800 --> 04:42.420 So I'm going to draw a debug sphere. 04:44.540 --> 04:48.860 And I'm going to draw it at the location of this actor. 04:48.860 --> 04:50.420 So get actor location. 04:54.040 --> 04:56.050 And I'm going to get the sphere. 04:58.300 --> 05:00.220 And get sphere radius. 05:00.490 --> 05:03.880 That's going to be the radius for my sphere that I draw. 05:04.150 --> 05:05.410 I'm going to make it red. 05:06.630 --> 05:12.930 I'm going to let the duration be five seconds and let's just see what happens here. 05:13.200 --> 05:17.440 Now, compiling isn't going to work because Sphere is not blueprint visible. 05:17.460 --> 05:19.530 We have not exposed it to the event graph. 05:19.530 --> 05:28.650 So just really quickly, we have to close the editor and go into Aura projectile dot H and we have to 05:28.650 --> 05:30.180 expose the sphere. 05:30.210 --> 05:36.240 Now that means we either have to move it into the protected section or get around having the private 05:36.240 --> 05:38.940 variable with a meta specifier. 05:39.060 --> 05:40.080 Here's what I mean. 05:40.080 --> 05:46.110 If we wanted blueprint read only and we want to keep Sphere in the private section, we'd have to say 05:46.110 --> 05:49.650 meta equals allow private access. 05:50.810 --> 05:51.800 Equals true. 05:53.450 --> 05:57.770 That's how you get around having a blueprint read only and a private section. 05:57.770 --> 06:02.540 But rather than doing that, I prefer to just move it into the protected section. 06:02.540 --> 06:09.230 And that way we don't have to make it private in C plus plus but exposed in blueprint. 06:09.260 --> 06:12.590 We're just going to make it a protected variable. 06:13.250 --> 06:19.670 So now that the sphere is exposed, we can now launch the editor and use it in the blueprint. 06:21.450 --> 06:23.940 So we'll go ahead and open up that blueprint. 06:23.970 --> 06:28.680 We see that it compiles just fine and let's see what happens. 06:33.320 --> 06:40.610 Okay, so that half a second is a bit long because if I'm closer than that, that fireball passes straight 06:40.610 --> 06:41.360 through me. 06:42.040 --> 06:45.250 So this is kind of a long delay. 06:45.280 --> 06:48.250 Let's try 0.1 seconds and see how that looks. 06:48.250 --> 06:51.100 That should be a fifth shorter. 06:51.430 --> 06:52.120 There we go. 06:52.120 --> 06:54.400 So if we're too close like this. 06:54.400 --> 06:55.240 Close. 06:57.580 --> 06:59.570 Then it should pass through us. 06:59.590 --> 07:02.170 I guess we're still going to get hit. 07:03.780 --> 07:05.310 So that's still okay. 07:06.950 --> 07:07.940 Now let's see. 07:07.940 --> 07:10.220 I hit stop and we get a blueprint. 07:10.220 --> 07:17.390 Runtime error attempted to access sphere via properties Sphere but sphere is not valid pending kill 07:17.390 --> 07:18.530 or garbage. 07:18.530 --> 07:21.290 And this is in draw debug sphere. 07:21.290 --> 07:25.340 So that's going to be for draw debug sphere. 07:25.430 --> 07:30.020 We can always avoid that kind of error by doing a validated get. 07:30.020 --> 07:33.770 So we can right click on sphere, we can convert to a validated get. 07:33.770 --> 07:39.380 And this is like checking if a pointer is not null or rather checking is valid. 07:39.380 --> 07:44.570 So even if it's not null but still pending kill we won't make it past this. 07:47.940 --> 07:49.740 Okay, so things still work. 07:53.610 --> 08:00.570 And if I'm really close to the enemy and I fire over there, well, I guess that's kind of beyond the 08:00.570 --> 08:01.530 reach of it. 08:04.910 --> 08:06.230 But this is looking good. 08:08.440 --> 08:15.640 So again, we're attempting to access sphere when it's not valid and that's only when drawing the debug 08:15.640 --> 08:16.420 sphere. 08:16.780 --> 08:22.570 But before we get rid of the debug sphere, I'm going to take my sphere and increase its radius. 08:24.210 --> 08:31.650 That way we can see if we can have a bigger radius without worrying about a premature explosion. 08:31.770 --> 08:34.770 Let's see this happen in action. 08:37.480 --> 08:38.110 Great. 08:39.520 --> 08:44.590 So now it's not so easy to miss and we still have a little bit of a delay. 08:49.750 --> 08:50.650 Excellent. 08:51.190 --> 08:51.550 Okay. 08:51.550 --> 08:54.690 So I'm going to remove that draw debug sphere. 08:54.700 --> 09:02.170 We don't need that anymore and we now have a slight delay before enabling collision for the Firebolt. 09:02.200 --> 09:02.560 Okay. 09:02.560 --> 09:08.200 So all of that just so that we could have the same behavior as we had before, right? 09:08.230 --> 09:17.890 We have a firebolt wielding shaman and really, you know, that's really all it does is launch firebolt. 09:17.890 --> 09:20.750 But we want it to summon as well. 09:20.770 --> 09:29.080 So what we need to do is we need to put some custom functionality in our behavior tree specific to the 09:29.080 --> 09:33.100 Elementalist and we'll do that in the next video. 09:33.280 --> 09:34.150 It's a great job. 09:34.150 --> 09:35.260 I'll see you soon.