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These are the user uploaded subtitles that are being translated: 1 1 00:00:00,000 --> 00:00:04,088 [MUSIC] 2 2 00:00:04,088 --> 00:00:08,070 I'm sure you've heard the famous saying, tidy hierarchy, tidy mind. 3 3 00:00:08,070 --> 00:00:12,464 Well, if we look at our hierarchy when we start to place down defenders, 4 4 00:00:12,464 --> 00:00:14,783 it becomes very untidy, very messy. 5 5 00:00:14,783 --> 00:00:17,936 You can see all these gnomes and axes, all sorts of stuff going on, 6 6 00:00:17,936 --> 00:00:21,597 which makes it difficult if we need to go and figure something out mid-game, 7 7 00:00:21,597 --> 00:00:23,550 pause it and find what's going on. 8 8 00:00:23,550 --> 00:00:25,120 Just much better to have it tidy, 9 9 00:00:25,120 --> 00:00:28,880 particularly when you start making massive projects, which I know you will. 10 10 00:00:28,880 --> 00:00:33,640 So I'm going to jump over into my defender spawner script. 11 11 00:00:33,640 --> 00:00:38,550 And up at the very top, gonna create a game object, gameObject, 12 12 00:00:38,550 --> 00:00:43,060 that will be called defenderParent. 13 13 00:00:45,700 --> 00:00:48,060 Now I need to put back in my start method. 14 14 00:00:48,060 --> 00:00:48,760 So start. 15 15 00:00:48,760 --> 00:00:50,200 What do I wanna have happen on start? 16 16 00:00:50,200 --> 00:00:52,870 Well, I wanna call a method that 17 17 00:00:52,870 --> 00:00:57,100 will take care of creating the defender child parent relationship. 18 18 00:00:57,100 --> 00:01:01,630 So I'll call this CreateDefenderParent. 19 19 00:01:01,630 --> 00:01:03,705 And parentheses, semicolon. 20 20 00:01:03,705 --> 00:01:09,150 Right-click, quick actions and refactors, to create that as a method just below it. 21 21 00:01:09,150 --> 00:01:10,770 And what will be in here? 22 22 00:01:10,770 --> 00:01:19,340 Well, first step, I'm going to define my defenderParent object as GameObject.find. 23 23 00:01:19,340 --> 00:01:20,697 So I want to find something. 24 24 00:01:20,697 --> 00:01:21,504 What am I finding? 25 25 00:01:21,504 --> 00:01:25,130 Well, I'm finding defenders. 26 26 00:01:25,130 --> 00:01:27,020 Now, string references we don't like. 27 27 00:01:27,020 --> 00:01:28,860 They're messy, they're dangerous. 28 28 00:01:28,860 --> 00:01:30,290 Did I even spell it correctly? 29 29 00:01:30,290 --> 00:01:32,480 I did on this occasion, yay for me. 30 30 00:01:32,480 --> 00:01:33,560 What's a better way to do this? 31 31 00:01:33,560 --> 00:01:35,390 Well, we've just been learning about constant. 32 32 00:01:35,390 --> 00:01:41,630 So at the top of our script let's add ourselves a const, which will be a string. 33 33 00:01:41,630 --> 00:01:45,155 And we'll use capitals to show that it's a const, 34 34 00:01:45,155 --> 00:01:48,740 DEFENDER_PARENT_NAME, and that will equal what? 35 35 00:01:48,740 --> 00:01:51,022 It will equal Defenders. 36 36 00:01:51,022 --> 00:01:54,150 So then we've added our string reference just once, and 37 37 00:01:54,150 --> 00:01:58,582 then in the future we will have this nice little hook that we can access when we're 38 38 00:01:58,582 --> 00:02:00,223 typing in our autocomplete. 39 39 00:02:00,223 --> 00:02:02,170 So down here, what are we looking for? 40 40 00:02:02,170 --> 00:02:05,750 Find, in parenthesis, I'm finding Defender, 41 41 00:02:05,750 --> 00:02:11,340 and you can see it's got DEFENDER_PARENT_NAME. 42 42 00:02:11,340 --> 00:02:14,420 So it's exactly the same, I could put my string reference down in there, or 43 43 00:02:14,420 --> 00:02:16,240 I could just do it once and define it. 44 44 00:02:16,240 --> 00:02:22,230 Now what if Defender, so this Defenders game object, what if it doesn't exist? 45 45 00:02:22,230 --> 00:02:25,290 What if there's no such thing in here or what if it's called something different? 46 46 00:02:25,290 --> 00:02:27,954 Then we don't wanna be having all sorts of errors and exceptions. 47 47 00:02:27,954 --> 00:02:31,467 So let's say, so if (!defenderParent), so 48 48 00:02:31,467 --> 00:02:37,480 if the defenderParent doesn't exist, if there is none, then what do we wanna do? 49 49 00:02:39,570 --> 00:02:45,626 We want to have defenderParent be defined as, so defenderParent equals new, 50 50 00:02:45,626 --> 00:02:50,874 creating a new, GameObject, and then DEFENDER_PARENT_NAME. 51 51 00:02:53,074 --> 00:02:55,660 See how nice that was to have auto completed? 52 52 00:02:55,660 --> 00:02:58,690 Okay, let's save that up, and, down the bottom, 53 53 00:02:58,690 --> 00:03:00,850 we actually need to use this one we instantiated. 54 54 00:03:00,850 --> 00:03:03,670 So down the very bottom, I've got SpawnDefender. 55 55 00:03:03,670 --> 00:03:07,861 And we're creating a new defender, so 56 56 00:03:07,861 --> 00:03:16,090 I will write newDefender.transform.parent is going to be equal to what? 57 57 00:03:16,090 --> 00:03:20,650 It's going to be equal to 58 58 00:03:20,650 --> 00:03:26,957 defenderParent.transform;. 59 59 00:03:26,957 --> 00:03:33,400 So that means that it's instantiated as a child to our defenderParent. 60 60 00:03:33,400 --> 00:03:36,360 Save that up, make sure it works, click on Play. 61 61 00:03:36,360 --> 00:03:41,415 When I drop down my gnomes, get down some gnomes, [SOUND] You can see that 62 62 00:03:41,415 --> 00:03:47,582 they are created within our, now pause, cuz we've still got out projectiles there. 63 63 00:03:47,582 --> 00:03:50,536 In our Defenders, you can see all of my gnomes, and 64 64 00:03:50,536 --> 00:03:53,580 within our defender gameObjects which is awesome. 65 65 00:03:53,580 --> 00:03:55,866 Okay, and because we do have all those messy projectiles, 66 66 00:03:55,866 --> 00:03:58,715 we need to take care of those and that's going to be the challenge for you. 67 67 00:03:58,715 --> 00:04:00,787 So do the same with projectiles, 68 68 00:04:00,787 --> 00:04:04,590 have our projectiles parented to a projectile game object. 69 69 00:04:04,590 --> 00:04:06,243 Take that on, and I'll see you back on when you're done. 70 70 00:04:08,872 --> 00:04:10,790 Okay, where do we find this? 71 71 00:04:10,790 --> 00:04:12,460 What's the script we're looking in? 72 72 00:04:12,460 --> 00:04:14,410 Well, I'm going to jump in here. 73 73 00:04:14,410 --> 00:04:17,270 It's gonna be one of two, it's either gonna be Projectile or Shooter. 74 74 00:04:17,270 --> 00:04:21,040 I'm gonna have a little bit of quick glance at it, which of these, okay, 75 75 00:04:21,040 --> 00:04:23,980 I'm instantiating on fire, so I know that it's shooter. 76 76 00:04:23,980 --> 00:04:28,666 Open that up, same process, up at the top I'm gonna create 77 77 00:04:28,666 --> 00:04:33,280 myself a game object which I will call projectileParent. 78 78 00:04:35,150 --> 00:04:39,072 Within start we're gonna call the method weren't created yet 79 79 00:04:39,072 --> 00:04:41,669 which will be CreateProjectileParent. 80 80 00:04:41,669 --> 00:04:48,590 Right-click, Quick actions and Refactors, generate that method just down below here. 81 81 00:04:48,590 --> 00:04:49,767 What do we need to do? 82 82 00:04:49,767 --> 00:04:55,750 Well, projectileParent is going to be equal GameObject.Find. 83 83 00:04:55,750 --> 00:04:57,070 What are we finding? 84 84 00:04:57,070 --> 00:04:58,870 Well, we haven't created our const just yet. 85 85 00:04:58,870 --> 00:05:00,310 So, let's do that at the top. 86 86 00:05:00,310 --> 00:05:06,182 Const string, and this will be PROJECTILE PARENT, 87 87 00:05:06,182 --> 00:05:09,330 oops, _NAME. 88 88 00:05:09,330 --> 00:05:16,780 That's gonna be equal to or assigned as Projectiles. 89 89 00:05:17,950 --> 00:05:19,930 Semicolon, okay, so now what are we finding? 90 90 00:05:19,930 --> 00:05:25,510 We're finding PROJECTILE_PARENT_NAME, excellent. 91 91 00:05:25,510 --> 00:05:30,280 Same as before, if there is none, so if parentheses 92 92 00:05:31,310 --> 00:05:36,670 exclamation mark, there's no projectile parent, then what do we wanna do? 93 93 00:05:36,670 --> 00:05:38,640 Well, we better go ahead and create one. 94 94 00:05:38,640 --> 00:05:45,474 ProjectileParent = new GameObject, 95 95 00:05:45,474 --> 00:05:52,940 in parentheses PROJECT_PARENT_NAME. 96 96 00:05:52,940 --> 00:05:54,270 And you know what? 97 97 00:05:54,270 --> 00:05:55,960 I didn't do this deliberately, but I've gone and 98 98 00:05:55,960 --> 00:05:58,590 made a mistake that I'll show you how awesome this is. 99 99 00:05:58,590 --> 00:06:02,240 I've named it PROJECT_PARENT_NAME, that makes absolutely no sense, 100 100 00:06:02,240 --> 00:06:02,960 what was I thinking? 101 101 00:06:02,960 --> 00:06:04,650 So double-click on that. 102 102 00:06:04,650 --> 00:06:08,713 Control RR, I can see there's three instances and I can go in here and 103 103 00:06:08,713 --> 00:06:10,780 say PROJECTILE_PARENT_NAME. 104 104 00:06:10,780 --> 00:06:14,540 Apply, there we go, and we've easily renamed that. 105 105 00:06:14,540 --> 00:06:17,910 Thank you for having that as a const worked out nicely. 106 106 00:06:17,910 --> 00:06:20,931 And the of course we scroll all the way down to the bottom and 107 107 00:06:20,931 --> 00:06:24,703 we find where we are instantiating and we need to add an extra bit in here. 108 108 00:06:24,703 --> 00:06:28,420 Well, first of all, we're only instantiating this as an object. 109 109 00:06:28,420 --> 00:06:30,740 We need to instantiate as a game object. 110 110 00:06:30,740 --> 00:06:34,950 So what I mean by that, in front of instantiate we type GameObject, 111 111 00:06:36,480 --> 00:06:38,230 and then we give it a new name. 112 112 00:06:38,230 --> 00:06:45,545 So newProjectile = it's going to be a big line, but we'll put it on multiple lines, 113 113 00:06:45,545 --> 00:06:50,828 =, gonna give this a new line, Instantiate(projectile, 114 114 00:06:50,828 --> 00:06:55,970 and the position and the rotation, and as GameObject. 115 115 00:06:55,970 --> 00:06:56,670 Why do we do that? 116 116 00:06:56,670 --> 00:06:59,120 Well, that's we're casting it, that's what this is called, 117 117 00:06:59,120 --> 00:07:02,430 and we say as game object we need this as a game object so 118 118 00:07:02,430 --> 00:07:05,650 that we can place it within our hierarchy and we can manipulate it. 119 119 00:07:05,650 --> 00:07:10,427 When we instantiate not as a GameObject, it's instantiated just as an object. 120 120 00:07:10,427 --> 00:07:13,699 And you can see here, UnityEngine.Object.Instantiate, and 121 121 00:07:13,699 --> 00:07:15,670 we don't have as much control over it. 122 122 00:07:15,670 --> 00:07:20,070 A GameObject allows us to do things that if it's just an object, we can't do. 123 123 00:07:20,070 --> 00:07:24,613 Okay, it's a very simple explanation but basically, 124 124 00:07:24,613 --> 00:07:30,701 we're casting it as a GameObject, so that we can now do more stuff with it, 125 125 00:07:30,701 --> 00:07:33,812 which is going to say newProjectile. 126 126 00:07:33,812 --> 00:07:38,835 NewProjectile, if I can spell it correctly .transform.parent 127 127 00:07:38,835 --> 00:07:42,619 is going to be = projectileParent.transform. 128 128 00:07:42,619 --> 00:07:44,712 Save that, let's see how we go. 129 129 00:07:44,712 --> 00:07:47,130 Back over into Unity, click on Play. 130 130 00:07:48,240 --> 00:07:51,591 Drop down some cacti to make sure it's not just the gnomes that it works with. 131 131 00:07:51,591 --> 00:07:55,074 [SOUND] Okay, they're shooting a bunch of stuff. 132 132 00:07:55,074 --> 00:07:56,860 We're gonna have explosions that come and 133 133 00:07:56,860 --> 00:08:00,010 go cuz they're being destroyed when they have done their business. 134 134 00:08:00,010 --> 00:08:02,700 And if we look, there's a Projectiles game object and 135 135 00:08:02,700 --> 00:08:04,900 we've got some projectiles that are within that. 136 136 00:08:04,900 --> 00:08:06,620 Excellent so that's mission accomplished. 137 137 00:08:06,620 --> 00:08:07,600 Tidied up the hierarchy. 138 138 00:08:07,600 --> 00:08:09,330 It might seem like a small minor thing but 139 139 00:08:09,330 --> 00:08:11,640 it's really important to get into these habits. 140 140 00:08:11,640 --> 00:08:14,390 So that you can impress your colleagues when you're out there working in 141 141 00:08:14,390 --> 00:08:17,230 the game industry with, look how neat and tidy my hierarchy is. 142 142 00:08:17,230 --> 00:08:18,750 That's one reason of many. 143 143 00:08:18,750 --> 00:08:21,270 So great work, and I'll see you in the next lecture. 13952