1 00:00:04,460 --> 00:00:05,240 ‫Hello and welcome. 2 00:00:05,240 --> 00:00:10,250 ‫In this lecture, we're going to be creating a killer mobile game mode, which is going to be just one 3 00:00:10,250 --> 00:00:17,270 ‫of the possible game modes that we can create due to having a virtual -- killed method that could 4 00:00:17,270 --> 00:00:19,940 ‫be called on any of the game modes that we want. 5 00:00:19,970 --> 00:00:24,560 ‫Let's dive in and see how we're going to implement this virtual method. 6 00:00:25,540 --> 00:00:28,640 ‫So we would like our game to be able to end. 7 00:00:28,660 --> 00:00:29,760 ‫What does it mean for a game to end? 8 00:00:29,770 --> 00:00:34,990 ‫It means that we go into some sort of state where we are the one or we've lost. 9 00:00:34,990 --> 00:00:37,240 ‫We inform the player using some UI. 10 00:00:37,270 --> 00:00:40,810 ‫We give them the option to maybe restart and play it again. 11 00:00:41,050 --> 00:00:43,020 ‫Something along those lines. 12 00:00:43,030 --> 00:00:46,900 ‫Now the classes involved with this typically are a game mode. 13 00:00:46,900 --> 00:00:52,420 ‫The game mode is responsible for deciding rules about the game, such as who won and who lost. 14 00:00:52,780 --> 00:00:56,470 ‫And for that, we're going to need to know who is being killed. 15 00:00:56,470 --> 00:01:02,500 ‫So we're going to have this virtual method here called Pawn Killed, which will be called from our shooter 16 00:01:02,500 --> 00:01:09,370 ‫pawn when it dies, whether or not it is the AI or it is the player that is doing the dying. 17 00:01:10,360 --> 00:01:15,310 ‫And furthermore, I want to add a little complication here, which is that we'll have different game 18 00:01:15,310 --> 00:01:18,550 ‫modes derived from our main shooter game mode. 19 00:01:18,550 --> 00:01:20,320 ‫They will implement that game mode. 20 00:01:20,320 --> 00:01:21,580 ‫That's what the arrow means here. 21 00:01:21,580 --> 00:01:25,840 ‫It's often a little bit counterintuitive the way the arrow goes, but kill them all. 22 00:01:25,840 --> 00:01:33,310 ‫Game mode inherits from the shooter game mode and it overrides pawn killed in order to count up and 23 00:01:33,310 --> 00:01:35,770 ‫decide differently on the rules of the game. 24 00:01:35,770 --> 00:01:41,980 ‫So that's why I want to put a virtual pawn killed method over in the parent shooter game mode and then 25 00:01:42,130 --> 00:01:48,130 ‫implement or override it again in the kill all game mode, which is going to be the game mode that we're 26 00:01:48,130 --> 00:01:49,570 ‫implementing for ourselves. 27 00:01:49,570 --> 00:01:54,490 ‫And you might choose to do different game modes where maybe you just want to kill a certain amount of 28 00:01:54,490 --> 00:01:58,450 ‫the enemies in the level rather than all of them or something along those lines. 29 00:01:58,450 --> 00:02:00,670 ‫Maybe a capture the flag, something different. 30 00:02:01,900 --> 00:02:08,560 ‫But basically what's going to happen is the shooter -- is going to find the game mode that's got the 31 00:02:08,560 --> 00:02:13,060 ‫type shooter game mode and it's going to call it's -- killed. 32 00:02:13,060 --> 00:02:19,060 ‫And then depending on whatever implementation there's actually there, it's going to go through to the 33 00:02:19,060 --> 00:02:21,250 ‫implementation via the override. 34 00:02:21,910 --> 00:02:28,390 ‫Now, another complication here is that our UI logic and restarting logic is really something that should 35 00:02:28,390 --> 00:02:35,200 ‫happen in the player controller UI generally being the purview of the player rather than something global 36 00:02:35,200 --> 00:02:36,310 ‫like the game mode. 37 00:02:36,340 --> 00:02:42,850 ‫This is especially true in games that are multiplayer because the game mode doesn't actually exist on 38 00:02:42,850 --> 00:02:45,160 ‫the player's machine, it only exists on the server. 39 00:02:45,160 --> 00:02:49,270 ‫So any UI stuff should be going on in the player controller. 40 00:02:49,540 --> 00:02:52,690 ‫That's a complication we don't need to worry about because this is not a multiplayer game, but it's 41 00:02:52,690 --> 00:02:57,430 ‫still good to use the classes for what they're expected to be used for in Unreal. 42 00:02:57,880 --> 00:03:04,750 ‫So the player controller, the actual root player controller class has a virtual method called game 43 00:03:04,750 --> 00:03:12,610 ‫has ended specifically for this purpose so that the game mode can call this method and we can implement 44 00:03:12,610 --> 00:03:17,770 ‫it in our own shooter player controller to do UI, restarting, all that sort of stuff. 45 00:03:17,830 --> 00:03:23,590 ‫But we'll need to be calling it from our game mode when we have decided that the game is over. 46 00:03:23,590 --> 00:03:28,270 ‫So we'll call the virtual game has ended on the root player controller. 47 00:03:28,390 --> 00:03:33,910 ‫And then because that root player controller is actually a shooter, player controller will end up diverting 48 00:03:33,910 --> 00:03:35,290 ‫back and calling. 49 00:03:35,290 --> 00:03:36,130 ‫This game has ended. 50 00:03:36,130 --> 00:03:42,040 ‫So it seems like a circuitous route we're going to be calling from our shooter pawn via the shooter 51 00:03:42,040 --> 00:03:46,570 ‫game mode to the killer more game mode to the player controller to the shooter player controller. 52 00:03:46,570 --> 00:03:52,360 ‫But this allows us lots of flexibility in terms of saying, well, we can mix and match different player 53 00:03:52,360 --> 00:03:55,900 ‫controllers that will show UI in different ways, in different levels. 54 00:03:55,900 --> 00:04:00,130 ‫We can mix and match different game modes that are going to work in different ways, and that's the 55 00:04:00,130 --> 00:04:02,260 ‫reason for me architecting it in this way. 56 00:04:02,260 --> 00:04:07,750 ‫It's a little bit overkill for our project, but it shows you how this could extend to other projects 57 00:04:07,750 --> 00:04:11,970 ‫with Capture the Flag game modes and different sorts of player controller. 58 00:04:11,980 --> 00:04:14,500 ‫So let's have a go at implementing it. 59 00:04:14,530 --> 00:04:18,040 ‫We're going to go and first of all, find a route game mode. 60 00:04:18,040 --> 00:04:22,330 ‫There's already one created because I started from a C++ project. 61 00:04:22,330 --> 00:04:28,120 ‫We've got this simple shooter game mode base and what I want to do here is create a public function 62 00:04:28,120 --> 00:04:35,800 ‫which is going to return void and it's going to be -- killed and we're going to have to pass in the 63 00:04:35,830 --> 00:04:37,480 ‫-- that was killed here. 64 00:04:37,480 --> 00:04:42,400 ‫So it's going to be a -- star called -- killed like so. 65 00:04:42,400 --> 00:04:46,720 ‫And then at the beginning, we're going to make this a virtual method and we're going to go ahead and 66 00:04:46,720 --> 00:04:50,770 ‫create a basic implementation that essentially does nothing in here. 67 00:04:50,770 --> 00:04:52,930 ‫Then we're going to create a subclass. 68 00:04:52,930 --> 00:05:00,010 ‫So new C++ class, going to show all classes and we're going to look for our shooter, simple shooter 69 00:05:00,010 --> 00:05:02,230 ‫game mode base as our base class. 70 00:05:02,230 --> 00:05:12,010 ‫And we're going to call this the kill em all game mode like so and go ahead and create that class. 71 00:05:12,010 --> 00:05:18,100 ‫Then when that has compiled, I want to just switch over for a second and go to our shooter character. 72 00:05:18,130 --> 00:05:23,620 ‫CP And you can see in here we've got our is dead in the take damage method. 73 00:05:23,830 --> 00:05:30,490 ‫Now if this is dead, what I want to be doing is getting hold of our game mode and calling the -- 74 00:05:30,490 --> 00:05:31,180 ‫killed. 75 00:05:31,210 --> 00:05:38,470 ‫So the way we do this is we start with calling to get world in order to get the game mode, then it's 76 00:05:38,470 --> 00:05:40,690 ‫get auth game mode. 77 00:05:40,690 --> 00:05:46,750 ‫And then what we want to do is for this game mode to be of the correct type, which is the simple, 78 00:05:46,750 --> 00:05:52,150 ‫the root one, the simple shooter game mode that allows us to then switch out this character, use it 79 00:05:52,150 --> 00:05:54,910 ‫with different game modes such as capture the flag game modes. 80 00:05:55,060 --> 00:06:01,540 ‫So the way we can do this, we can use the angle brackets right in the get all game mode right here, 81 00:06:01,540 --> 00:06:07,900 ‫and we're going to do a simple shooter game mode and we're going to need to include that at the top. 82 00:06:08,320 --> 00:06:15,270 ‫So hash include simple shooter game mode base go. 83 00:06:15,550 --> 00:06:18,070 ‫So I didn't quite get the whole class name right? 84 00:06:18,070 --> 00:06:18,700 ‫I think so. 85 00:06:18,700 --> 00:06:22,180 ‫It's going to be a simple shooter game mode base. 86 00:06:22,360 --> 00:06:23,710 ‫That's what we're trying to get. 87 00:06:24,130 --> 00:06:29,290 ‫And we can go ahead and store that in a variable pointer, let's call it the game mode. 88 00:06:29,290 --> 00:06:35,860 ‫And then what we want to do is on this new line, we probably want to check that we have got this and 89 00:06:35,860 --> 00:06:36,790 ‫it's not a null pointer. 90 00:06:36,790 --> 00:06:40,630 ‫So game mode is not equal to a null pointer. 91 00:06:40,630 --> 00:06:47,680 ‫And then if it is not equal to a null pointer, that is where we want to call game mode arrow pawn killed 92 00:06:47,680 --> 00:06:50,590 ‫and the pawn killed is this like so? 93 00:06:50,590 --> 00:06:55,150 ‫So now the game mode is aware of a pawn having been killed. 94 00:06:55,170 --> 00:07:00,460 ‫Little mini challenge for you to override the kill them all game mode so that you can. 95 00:07:00,580 --> 00:07:06,880 ‫Log out when the -- is killed and set that as the default game mode in your map. 96 00:07:07,210 --> 00:07:09,680 ‫So hopefully you had a go at that little mini challenge. 97 00:07:09,700 --> 00:07:11,800 ‫We're going to go ahead and implement. 98 00:07:11,800 --> 00:07:17,740 ‫So I'm going to do this by copying the public section of our simple shooter game mode base, and it's 99 00:07:17,740 --> 00:07:19,540 ‫hard to keep track of all these things. 100 00:07:19,540 --> 00:07:24,070 ‫Then we're going to go over to our kill them all game mode base, which inherits from it. 101 00:07:24,310 --> 00:07:31,360 ‫And we're going to paste in the virtual method and we're going to add the override keyword to make sure 102 00:07:31,360 --> 00:07:33,850 ‫that we're overriding this method correctly. 103 00:07:34,730 --> 00:07:39,620 ‫Then I'm going to create an implementation over in the C++ for our KML game mode base. 104 00:07:40,100 --> 00:07:42,980 ‫This is where we should be getting that log message. 105 00:07:42,980 --> 00:07:48,430 ‫And just to be super careful, we know there's nothing in the implementation, but you never know. 106 00:07:48,440 --> 00:07:52,130 ‫Things might change later on and we might get bit in the bomb. 107 00:07:52,140 --> 00:07:55,250 ‫So we want to do a pawn killed. 108 00:07:56,310 --> 00:07:59,160 ‫Super -- killed with the -- killed. 109 00:07:59,190 --> 00:08:00,060 ‫Makes sense. 110 00:08:00,330 --> 00:08:09,630 ‫And then we want to do a you log in here basically saying that a -- was killed and we can see if that 111 00:08:09,630 --> 00:08:17,940 ‫works by going over into Unreal and compiling, then going to the blueprints item on the toolbar and 112 00:08:17,940 --> 00:08:23,250 ‫selecting in the project settings that our default game mode we want to be. 113 00:08:23,250 --> 00:08:29,040 ‫If we select game mode, base class, we want it to be the KML based game mode. 114 00:08:29,040 --> 00:08:31,770 ‫Basically, go ahead and do that. 115 00:08:31,770 --> 00:08:35,640 ‫In fact, that's not quite what we want us to do if we go and select. 116 00:08:35,640 --> 00:08:44,160 ‫We wanted it actually to be a blueprint child of that and we've already got a blueprint child that has 117 00:08:44,160 --> 00:08:45,060 ‫a lot of things set up. 118 00:08:45,060 --> 00:08:47,820 ‫So let's do a re parenting job there. 119 00:08:48,390 --> 00:08:54,090 ‫We'll go to the roots, we'll find the BP shooter game mode, which we've got here. 120 00:08:54,240 --> 00:09:02,790 ‫We're going to rename this BP, kill em all game mode, and then we can open that up, dock the window, 121 00:09:02,790 --> 00:09:10,500 ‫open the full blueprint editor, go to the class settings and change the parent to the KML game mode, 122 00:09:10,500 --> 00:09:11,940 ‫C++ basically. 123 00:09:12,030 --> 00:09:18,030 ‫And that way we should be running the correct code if we go to our message to our output log and hit 124 00:09:18,030 --> 00:09:25,740 ‫play and then kill off a character, a we have a problem does not appear to have the right set up. 125 00:09:25,740 --> 00:09:35,010 ‫So if we go back to our class defaults and change up the default -- class to being the BP shooter 126 00:09:35,010 --> 00:09:36,900 ‫character, that should be correct. 127 00:09:36,900 --> 00:09:39,330 ‫Save and compile just in case it got that wrong. 128 00:09:39,330 --> 00:09:42,000 ‫And then check my blueprints drop down here. 129 00:09:42,000 --> 00:09:44,700 ‫It's selected the KML game mode, the C++ one. 130 00:09:44,700 --> 00:09:49,530 ‫So we actually want to choose the blueprint one in here and go ahead and hit play. 131 00:09:49,530 --> 00:09:50,850 ‫Now we've got our pawn. 132 00:09:50,850 --> 00:09:57,330 ‫We can go ahead and kill this guy and you can see that a pawn was killed is printed log message. 133 00:09:57,330 --> 00:10:00,090 ‫So that is working fantastically. 134 00:10:00,240 --> 00:10:05,580 ‫Now in the next lecture, we're going to be looking at the second part of this, which is calling game 135 00:10:05,580 --> 00:10:12,870 ‫has ended when we actually do want to end the game and to be able to restart from there on. 136 00:10:12,960 --> 00:10:15,930 ‫So I will see you in that lecture.