1 00:00:03,190 --> 00:00:06,430 In this lecture, we are creating some scene persistence. 2 00:00:06,430 --> 00:00:10,780 So when I kill some enemies and grab some coins, when I die, those things are remembered and gone. 3 00:00:10,780 --> 00:00:14,800 But when I die, another couple of times they come back because we've restarted our game. 4 00:00:14,800 --> 00:00:16,000 So let's get started. 5 00:00:16,030 --> 00:00:19,600 Let's start the process in our hierarchy by right clicking Create Empty. 6 00:00:19,600 --> 00:00:25,900 I'm going to call this scene per persist and we'll reset that on the transform right click Reset. 7 00:00:25,900 --> 00:00:28,450 Now I need to create a script in my scripts folder. 8 00:00:28,480 --> 00:00:33,820 Right click Create C-sharp script will also call this scene per assist. 9 00:00:33,970 --> 00:00:39,880 Now, similar to the logic of when we were having our game session and we said, because the game session 10 00:00:39,880 --> 00:00:44,830 has a singleton on it, anything underneath that is also going to have that singleton logic applied. 11 00:00:44,830 --> 00:00:48,760 So in our case, the canvas with the lives and the score is going to persist. 12 00:00:48,790 --> 00:00:50,770 I'm going to do the same thing with scene persist. 13 00:00:50,770 --> 00:00:55,690 However, underneath that I'm going to be placing my coins and my enemies and anything else that I want 14 00:00:55,690 --> 00:01:02,050 to remember that if I collect one coin when the player dies, that coin is still collected until we 15 00:01:02,050 --> 00:01:07,180 restart that level or restart the game and need everything to kind of reset back to where it was. 16 00:01:07,180 --> 00:01:09,790 So click back on our scene, persist game object. 17 00:01:09,790 --> 00:01:12,220 I'll drag my scene persist script over in there. 18 00:01:12,220 --> 00:01:18,100 Now that I've got those two key elements, I can go to prefabs and prefab my scene persist so that as 19 00:01:18,100 --> 00:01:20,080 we change our code everything is cool. 20 00:01:20,080 --> 00:01:26,440 It'll update now prefab and I can click on same persist and drag underneath here my coins although I 21 00:01:26,440 --> 00:01:33,040 do want to group them first so right click create empty and we'll call this pick ups and then underneath 22 00:01:33,040 --> 00:01:36,190 pick ups we'll grab our coins, drop them underneath pick ups. 23 00:01:36,190 --> 00:01:36,700 That's great. 24 00:01:36,700 --> 00:01:39,220 And then pick ups we'll put underneath scene persist. 25 00:01:39,220 --> 00:01:44,350 We don't want to go and update our or override our prefab because we don't want these things. 26 00:01:44,350 --> 00:01:47,020 These this is content that's specific for our level. 27 00:01:47,020 --> 00:01:52,360 While we're here for good measure, I'm going to right click create empty and create some enemies once 28 00:01:52,360 --> 00:01:58,990 again reset the transform on that and we'll drag in a goober or two underneath my enemies. 29 00:01:58,990 --> 00:01:59,800 There we go. 30 00:01:59,800 --> 00:02:00,760 So click on that. 31 00:02:00,760 --> 00:02:02,320 Where are you hiding, Mr. Goober? 32 00:02:02,320 --> 00:02:04,180 You're way over there, Prop. 33 00:02:04,600 --> 00:02:09,880 Drop you into the scene and we'll grab the other goober drop you into the scene as well, just so that 34 00:02:09,880 --> 00:02:13,180 we can be testing these things out and we know that it's actually working. 35 00:02:13,180 --> 00:02:18,460 So we've got these things enemies and we want to drag enemies underneath scene persist. 36 00:02:18,460 --> 00:02:22,480 So those things should all now persist as we implement our logic in the script. 37 00:02:22,480 --> 00:02:23,800 So let's start that process. 38 00:02:23,800 --> 00:02:28,840 We'll jump over into our scripts, fire up, scene, persist and we go nice and fresh. 39 00:02:28,840 --> 00:02:34,630 I'm going to well, I'm here top left click on Explorer open up my game session double click on that 40 00:02:34,630 --> 00:02:35,740 closed scene Explorer again. 41 00:02:35,740 --> 00:02:36,880 So we've got plenty of space. 42 00:02:36,880 --> 00:02:42,100 I'm going to highlight my awake code block in here that's got our singleton on it and copy that so we 43 00:02:42,100 --> 00:02:43,320 can reuse our code a little bit. 44 00:02:43,320 --> 00:02:47,320 And you don't have to sit there watching me type everything and I highlight my start and update and 45 00:02:47,320 --> 00:02:47,890 remove that. 46 00:02:47,890 --> 00:02:50,140 We might put it back if we need it, but don't for now. 47 00:02:50,140 --> 00:02:53,590 Paste in the week we'll go through and just change some of the details in here. 48 00:02:53,590 --> 00:02:58,480 So some game sessions we will double click F2 that will allow us to rename. 49 00:02:58,480 --> 00:03:02,800 So instead of num game sessions can be number of seen persists. 50 00:03:03,220 --> 00:03:04,510 That's what this is called. 51 00:03:04,510 --> 00:03:09,880 Same persists instead of finding of type game session we're finding of type seen persist. 52 00:03:09,880 --> 00:03:13,630 Okay, so that's a singleton basically saying if you've got one already, you don't need another one. 53 00:03:13,630 --> 00:03:18,490 That's going to be great when the player dies and then respawns and we restart the level, there'll 54 00:03:18,520 --> 00:03:20,470 be a seen persist there already. 55 00:03:20,470 --> 00:03:25,050 However, it's not going to be so good if the player exits the level. 56 00:03:25,090 --> 00:03:26,890 So what happens if you exit the level? 57 00:03:26,890 --> 00:03:32,590 We've already got a scene persist that has all its information about this is what I believe should be 58 00:03:32,590 --> 00:03:37,960 contained within my scene persist and it's going to destroy any scene persist that we create for level 59 00:03:37,960 --> 00:03:39,520 two and level three and level four and so on. 60 00:03:39,520 --> 00:03:43,090 So what we need to do is have some logic in here, very simple. 61 00:03:43,090 --> 00:03:46,240 I'm going to keep this whole script, this whole class, very simple. 62 00:03:46,240 --> 00:03:49,120 So it's easy to understand we need one more thing in here. 63 00:03:49,120 --> 00:03:52,300 But before we do that one thing, let's go and create ourselves a little bit of content. 64 00:03:52,300 --> 00:03:57,070 So I'm going to save up level one, jump over into level two and we'll pop in here. 65 00:03:57,070 --> 00:03:58,720 Our prefab scene persist. 66 00:03:58,720 --> 00:03:59,260 Where are you seen? 67 00:03:59,260 --> 00:04:00,160 Persist There you go. 68 00:04:00,160 --> 00:04:05,800 Prefab grab our enemies and drag them underneath scene persist grab our pick ups and drag them underneath 69 00:04:05,800 --> 00:04:06,700 scene persist as well. 70 00:04:06,700 --> 00:04:12,130 So these should now be seen persisting if we've done this correctly and I save that and just go to level 71 00:04:12,130 --> 00:04:15,190 three while I'm here so we can do proper play testing on this. 72 00:04:15,220 --> 00:04:19,870 All my goobers just mushed around wherever he is, I'm going to right click create empty and tidy this 73 00:04:19,870 --> 00:04:24,520 up by creating enemies right click to reset our enemies game objects. 74 00:04:24,520 --> 00:04:27,730 I will grab all of the goobers except not the player. 75 00:04:27,730 --> 00:04:28,600 You're not a goober. 76 00:04:28,600 --> 00:04:30,760 You stay out of here, drag them under enemies. 77 00:04:30,760 --> 00:04:31,330 That's good. 78 00:04:31,330 --> 00:04:33,820 And then enemies we can put underneath game session. 79 00:04:33,820 --> 00:04:35,110 Do we have any coins in here? 80 00:04:35,110 --> 00:04:39,070 I just quickly chuck a couple of coins in here and our players should probably go back to where the 81 00:04:39,070 --> 00:04:40,960 player needs to start off, which was where? 82 00:04:40,960 --> 00:04:42,040 Up the top here. 83 00:04:42,040 --> 00:04:42,550 Down the bottom. 84 00:04:42,550 --> 00:04:45,040 Down the bottom here before the bouncy bounce just there. 85 00:04:45,040 --> 00:04:49,660 And we'll put in a couple of coins at the start so that we can make sure this all works properly. 86 00:04:49,660 --> 00:04:53,380 Prefabs, coin, drag a coin just in front of the player there. 87 00:04:53,380 --> 00:04:57,400 Do a big jumping to the coin and one more so we can test that all this works properly. 88 00:04:58,030 --> 00:04:58,870 So at two coins. 89 00:04:58,870 --> 00:05:02,410 So once again, right click create empty call this pick ups. 90 00:05:03,060 --> 00:05:08,040 Reset the transform supporting to keep all these things organized, mostly because your hierarchy doesn't 91 00:05:08,040 --> 00:05:12,540 then get filled up with a whole bunch of gunk, but also so we can do these exact same things like grabbing 92 00:05:12,540 --> 00:05:14,560 the pickups and easily putting them underneath. 93 00:05:14,580 --> 00:05:16,950 Our scene persists, which I haven't put in there yet. 94 00:05:16,950 --> 00:05:19,230 Oh, sorry, I wouldn't put enemies under game session. 95 00:05:19,230 --> 00:05:19,980 What are you doing, Rick? 96 00:05:19,980 --> 00:05:20,730 Something crazy. 97 00:05:20,730 --> 00:05:22,440 So scene persist prefab. 98 00:05:22,440 --> 00:05:23,550 We drag that into the scene. 99 00:05:23,550 --> 00:05:24,870 Sorry, you probably picked that up. 100 00:05:24,870 --> 00:05:25,470 I missed it. 101 00:05:25,470 --> 00:05:28,290 I'm going to grab my enemies and put them where they belong on the scene. 102 00:05:28,290 --> 00:05:30,090 Persist in my pickups under scene. 103 00:05:30,090 --> 00:05:30,780 Persist as well. 104 00:05:30,810 --> 00:05:33,210 Okay sanity check to make sure Rick isn't insane. 105 00:05:33,240 --> 00:05:34,470 Game session canvas. 106 00:05:34,470 --> 00:05:35,190 Yes, that's right. 107 00:05:35,190 --> 00:05:35,850 Same persist. 108 00:05:35,850 --> 00:05:36,570 Enemies and pickups. 109 00:05:36,570 --> 00:05:37,620 Yes, that looks right. 110 00:05:37,620 --> 00:05:38,400 Okay, good one. 111 00:05:38,400 --> 00:05:39,990 Now I'll go all the way back to level one. 112 00:05:39,990 --> 00:05:43,590 So click on levels level one so we can test this from the get go. 113 00:05:43,620 --> 00:05:46,260 I'm just going to move this coin a little bit higher so it's not the way the enemy. 114 00:05:46,260 --> 00:05:51,090 So now that we've got all that structure set up, what I want to do is say when the player reaches the 115 00:05:51,090 --> 00:05:58,350 end of a level or loses all of their lives, I want to have my scene persist, be destroyed, so that 116 00:05:58,350 --> 00:06:03,570 when you're on a new level, that new level scene persist is going to be the boss. 117 00:06:03,570 --> 00:06:05,280 It's going to be controlling things. 118 00:06:05,280 --> 00:06:08,460 So I'm going to give this to you is a little bit more of an abstract challenge. 119 00:06:08,460 --> 00:06:10,050 The code is pretty simple. 120 00:06:10,050 --> 00:06:15,570 We've done this before and we'll be continuing to practice our basic concepts to reinforce them. 121 00:06:15,570 --> 00:06:20,550 And in this case, we're going to create a public method that we can call wherever we need to in order 122 00:06:20,550 --> 00:06:25,680 to reset our scene, persist and then make sure you play test so that you can be sure there are no edge 123 00:06:25,680 --> 00:06:26,880 cases, no weird things. 124 00:06:26,880 --> 00:06:31,080 Like if you pick up three coins when you've got one life and then you die and you go back to that level, 125 00:06:31,080 --> 00:06:33,090 then you go into this level without picking up any coins. 126 00:06:33,090 --> 00:06:36,000 So do a little bit of quality assurance testing on it to make sure you've got it. 127 00:06:36,000 --> 00:06:36,480 So there you go. 128 00:06:36,480 --> 00:06:37,890 There's a challenge plus video. 129 00:06:37,890 --> 00:06:39,000 See you back here when you're done. 130 00:06:41,610 --> 00:06:42,780 Insane persists. 131 00:06:42,780 --> 00:06:43,770 Yes, I mean, sane persists. 132 00:06:43,770 --> 00:06:47,490 What I need to do, first of all, is create public void. 133 00:06:47,640 --> 00:06:53,760 And this I'll call reset scene persist just to be really clear what it is parentheses. 134 00:06:53,880 --> 00:07:00,630 Kelly braces and here's really simply just destroy me destroy game object not magazine Rick but me is 135 00:07:00,630 --> 00:07:03,480 in this particular game object and then save all of that. 136 00:07:03,480 --> 00:07:05,220 So this is really simple code. 137 00:07:05,220 --> 00:07:10,200 There's a lot more nifty ways that you can create this as you become more capable and confident as a 138 00:07:10,200 --> 00:07:10,830 programmer. 139 00:07:10,830 --> 00:07:16,230 But I want to keep practicing these core concepts of if you have something as public within here, we 140 00:07:16,230 --> 00:07:19,710 can call it from somewhere else, and it affects this particular class. 141 00:07:19,710 --> 00:07:22,830 And so where do we need to be calling this public method? 142 00:07:22,830 --> 00:07:28,950 Well, if I go into my game session, this is one place where let's see, let's see. 143 00:07:28,950 --> 00:07:29,880 Not take life. 144 00:07:29,880 --> 00:07:32,730 We don't need to call it there, but in reset game session. 145 00:07:32,730 --> 00:07:37,620 So in other words, when the entire game ends, we absolutely want to be resetting our scene persist. 146 00:07:37,620 --> 00:07:43,230 So just before we load the new scene, I'm going to find object of type. 147 00:07:43,230 --> 00:07:48,960 It will be seen persist parentheses and then we're going to be calling what we'll be calling. 148 00:07:48,960 --> 00:07:50,270 The reset scene persists. 149 00:07:50,280 --> 00:07:52,530 We just created parentheses semicolon. 150 00:07:52,530 --> 00:07:54,630 I'm going to copy that because I'll need it one more time. 151 00:07:54,630 --> 00:07:56,760 Save this script into my explorer. 152 00:07:56,760 --> 00:07:59,250 The other spot I think I need to do this is level exit. 153 00:07:59,250 --> 00:08:00,420 When we leave a level. 154 00:08:00,420 --> 00:08:04,320 So open that up and I'm going to look for where we would do this. 155 00:08:04,320 --> 00:08:08,340 So on trigger, if it's the player, start the routine to load the next level. 156 00:08:08,340 --> 00:08:09,720 We want to wait our little bit of time. 157 00:08:09,720 --> 00:08:14,400 We're waiting in here, but prefer if to do it just before we actually load the new thing. 158 00:08:14,400 --> 00:08:16,830 Let's destroy our scene. 159 00:08:16,830 --> 00:08:17,340 Persist. 160 00:08:17,340 --> 00:08:20,580 So I'll paste that in there under load next level. 161 00:08:20,580 --> 00:08:25,410 After we've done all of our scrutiny and yielding and all that good stuff, we want to find object to 162 00:08:25,410 --> 00:08:26,820 type, scene persist and reset. 163 00:08:26,850 --> 00:08:27,600 Same persist. 164 00:08:27,600 --> 00:08:31,140 So save that up and I'm pretty sure they're the only spots for now. 165 00:08:31,140 --> 00:08:36,809 You might have something in the future where the player can, for example, push a button to exit, 166 00:08:36,809 --> 00:08:41,190 to to reload or a main menu or some other element. 167 00:08:41,190 --> 00:08:42,510 And you need to be thinking of this. 168 00:08:42,510 --> 00:08:47,910 And this is one of the downsides of using this kind of public method where we know in one of our scripts 169 00:08:47,910 --> 00:08:52,020 in here scene persist, we've got this public thing and then go and put it in all of the other places. 170 00:08:52,020 --> 00:08:53,130 Put it here, put it there. 171 00:08:53,130 --> 00:08:56,070 It's really great for us at this beginner plus stage. 172 00:08:56,070 --> 00:09:00,450 It's a nice, simple way of doing things, but there are more detailed ways that you'll learn to do 173 00:09:00,450 --> 00:09:01,740 these things in the future. 174 00:09:01,740 --> 00:09:03,240 That's a little bit more scalable. 175 00:09:03,240 --> 00:09:06,660 But for now, this is a perfectly fine way of doing things for where we're at. 176 00:09:06,660 --> 00:09:09,450 So let's jump in before we congratulate ourselves too much. 177 00:09:09,450 --> 00:09:10,650 Let's make sure it works. 178 00:09:10,650 --> 00:09:15,750 I should have my coins persisting in here when I jump on them, and even when I shoot a goober, they 179 00:09:15,750 --> 00:09:18,750 will go shop one goober, grab one coin, fell down into the hole. 180 00:09:18,750 --> 00:09:19,170 Great. 181 00:09:19,170 --> 00:09:22,170 So those things no longer appear exactly what I wanted. 182 00:09:22,170 --> 00:09:23,250 Now, let's see. 183 00:09:23,250 --> 00:09:24,000 We've got one coin. 184 00:09:24,000 --> 00:09:26,190 One goober will go through the level exit. 185 00:09:26,190 --> 00:09:27,240 That coin is there. 186 00:09:27,240 --> 00:09:27,420 Good. 187 00:09:27,420 --> 00:09:32,250 Grab a few of these coins and then let's just see what happens when we die at this stage. 188 00:09:32,250 --> 00:09:32,850 Great. 189 00:09:32,850 --> 00:09:34,110 Those coins are no longer there. 190 00:09:34,110 --> 00:09:35,160 Let's see what happens when we die. 191 00:09:35,160 --> 00:09:36,630 Now, back to the first one, okay? 192 00:09:36,630 --> 00:09:37,890 And these coins have reappeared. 193 00:09:37,890 --> 00:09:38,970 The group is reappeared. 194 00:09:38,970 --> 00:09:44,460 That means we should have this successfully set up where we have our seen persistence, but only when 195 00:09:44,460 --> 00:09:45,000 we need it. 196 00:09:45,000 --> 00:09:48,810 And just a reminder of why we needed to have that final public method in there. 197 00:09:48,810 --> 00:09:53,190 It's because if this scene persists, is told, you need to stay around forever. 198 00:09:53,210 --> 00:09:58,290 We go into next level and we get to the next level and it says, okay, there's already a scene persist 199 00:09:58,290 --> 00:10:01,740 from the previous level, so I won't bring in my scene persistence than these enemies. 200 00:10:01,740 --> 00:10:04,620 And these pickups might actually not appear in the scene. 201 00:10:04,620 --> 00:10:06,690 So that's why we needed to do that public method. 202 00:10:06,690 --> 00:10:11,640 But I'm feeling pretty good now about our flow and about our features and our functionality, so I'll 203 00:10:11,640 --> 00:10:12,540 see you in the next lecture.