1 00:00:04,770 --> 00:00:06,070 ‫Hey, welcome back. 2 00:00:06,090 --> 00:00:11,850 ‫In this video, we're going to make the distinction between instances of a particular blueprint class 3 00:00:11,850 --> 00:00:17,130 ‫versus the default blueprint, which is the blueprint that applies to all instances. 4 00:00:17,130 --> 00:00:25,050 ‫We're also going to see how we can assign, read or write access for a particular C++ variable in blueprints. 5 00:00:25,050 --> 00:00:26,360 ‫So let's get started. 6 00:00:26,370 --> 00:00:30,810 ‫We're now ready to start exposing some of our components to Blueprint. 7 00:00:30,930 --> 00:00:36,810 ‫So here we have our components and we've seen that if we click on each one of them, our details panel 8 00:00:36,810 --> 00:00:38,040 ‫is completely empty. 9 00:00:38,040 --> 00:00:44,070 ‫So we need to learn how we can expose certain properties to blueprint, and we do that by the use of 10 00:00:44,070 --> 00:00:45,960 ‫our U property macro. 11 00:00:45,960 --> 00:00:51,060 ‫So let's jump back into VS code and take a look at the You property macro. 12 00:00:51,090 --> 00:00:53,010 ‫This is a special macro. 13 00:00:53,010 --> 00:00:59,730 ‫It's unique to Unreal Engine and it's got this set of parentheses because it can take input parameters 14 00:00:59,730 --> 00:01:06,390 ‫now in order to show how to expose things in certain ways, we're just going to create a couple of throwaway 15 00:01:06,390 --> 00:01:09,870 ‫variables that we can just delete when we're done. 16 00:01:09,870 --> 00:01:15,450 ‫We're just going to use these to see how this exposure thing works so we can make some integers. 17 00:01:15,450 --> 00:01:21,600 ‫Let's make an INT 32 and I'm going to call this int 32 visible anywhere int. 18 00:01:21,600 --> 00:01:27,090 ‫And just right here I'm going to initialize this to a value, say 12. 19 00:01:27,090 --> 00:01:33,390 ‫Now in order to expose this to the reflection system, we're going to need a new property macro. 20 00:01:33,390 --> 00:01:36,480 ‫Now, this is just a plain integer variable. 21 00:01:36,660 --> 00:01:41,880 ‫It's not a component like these, so it's not going to show up in the components tab. 22 00:01:41,910 --> 00:01:48,600 ‫Remember here in the blueprint, we have this components section and any components show up here, but 23 00:01:48,600 --> 00:01:51,630 ‫any regular variables, those are going to show up. 24 00:01:51,630 --> 00:01:58,590 ‫If we click on BP Pond, Tank Self, for example, this is where we see all the other variables that 25 00:01:58,590 --> 00:02:00,120 ‫are not components. 26 00:02:00,120 --> 00:02:05,250 ‫So back in vs code, let's decide how we're going to expose visible anywhere. 27 00:02:05,250 --> 00:02:09,600 ‫INT Well, I'm going to introduce you to some you property keywords. 28 00:02:09,600 --> 00:02:13,090 ‫These are options that can go into the parentheses for the U. 29 00:02:13,110 --> 00:02:14,280 ‫Property macro. 30 00:02:14,490 --> 00:02:17,400 ‫For this one, we're going to add visible anywhere. 31 00:02:17,430 --> 00:02:19,860 ‫Now let's go ahead and compile this. 32 00:02:20,100 --> 00:02:20,520 ‫Okay. 33 00:02:20,520 --> 00:02:23,250 ‫So we've compiled let's jump back into the editor. 34 00:02:23,250 --> 00:02:30,780 ‫And here in BP Pond Tank, I have the BP pond tank self-selected here and I can search in the details 35 00:02:30,780 --> 00:02:38,340 ‫panel for visible and here is my visible anywhere int notice the blueprint places spaces in between 36 00:02:38,340 --> 00:02:44,160 ‫each of the words thanks to the way we've named this with Camel Case and check this out we can see that 37 00:02:44,160 --> 00:02:46,350 ‫it has a value of 12 and it's grayed out. 38 00:02:46,350 --> 00:02:48,960 ‫We can't actually edit this at all. 39 00:02:48,960 --> 00:02:50,580 ‫So that's what visible anywhere means. 40 00:02:50,580 --> 00:02:54,270 ‫It means it's visible, but we cannot edit this property. 41 00:02:54,300 --> 00:02:57,540 ‫Okay, so let's go ahead and create another INT 32. 42 00:02:57,540 --> 00:03:00,960 ‫I'm going to call this one edit anywhere int. 43 00:03:01,260 --> 00:03:10,230 ‫And for this I'll just give it a value, say 22 and this one will get its own U property macro and instead 44 00:03:10,230 --> 00:03:13,770 ‫of visible anywhere, I'm going to give this one the keyword. 45 00:03:13,770 --> 00:03:15,210 ‫Edit Anywhere. 46 00:03:15,300 --> 00:03:21,690 ‫Let's go ahead and compile this and back here in the editor I'm going to search instead for edit anywhere 47 00:03:21,690 --> 00:03:28,080 ‫and here is my edit anywhere and and you can see it has the value 22 only it's not grayed out anymore. 48 00:03:28,080 --> 00:03:30,060 ‫I can select it, I can change it. 49 00:03:30,060 --> 00:03:31,320 ‫It's editable. 50 00:03:31,320 --> 00:03:32,970 ‫That's what edit anywhere means. 51 00:03:32,970 --> 00:03:34,560 ‫It means we can change it. 52 00:03:34,590 --> 00:03:40,950 ‫So even though we're initializing it to 22 in C++, we can overwrite that value here in the blueprint 53 00:03:40,950 --> 00:03:42,600 ‫and give it a new value. 54 00:03:42,600 --> 00:03:48,300 ‫So now you've learned about Visible anywhere and edit anywhere, but there are more keywords than these 55 00:03:48,300 --> 00:03:48,780 ‫two. 56 00:03:48,780 --> 00:03:57,450 ‫For example, let's create a new int 32 and call this one visible instance only int and initialize this 57 00:03:57,450 --> 00:03:58,350 ‫to 11. 58 00:03:58,350 --> 00:04:05,100 ‫Now it's going to get its you property macro and the keyword I'll give to this one is visible instance 59 00:04:05,100 --> 00:04:05,940 ‫only. 60 00:04:05,940 --> 00:04:12,630 ‫Let's compile this and back here in the details panel in the blueprint I'm going to search for visible 61 00:04:12,630 --> 00:04:17,340 ‫now notice we can see visible anywhere int but where is our new variable? 62 00:04:17,340 --> 00:04:19,440 ‫We called it visible instance only. 63 00:04:19,440 --> 00:04:21,960 ‫INT See visible instance only. 64 00:04:21,960 --> 00:04:24,720 ‫INT Well, we can't see it here, but check this out. 65 00:04:24,720 --> 00:04:29,730 ‫I'm going to take our BP pond tank and drag one of these out into the world here. 66 00:04:29,730 --> 00:04:31,560 ‫And we can see in the world out liners. 67 00:04:31,560 --> 00:04:35,370 ‫Suddenly we have a BP pond tank here in the world. 68 00:04:35,370 --> 00:04:42,300 ‫Now, with this selected, I can come down here into the details panel and search for visible now check 69 00:04:42,300 --> 00:04:48,810 ‫this out now we can see our visible anywhere int and our visible instance only int. 70 00:04:48,810 --> 00:04:54,750 ‫So how can we can see it here, but we cannot see it when we're looking at the actual blueprint itself. 71 00:04:54,750 --> 00:04:56,790 ‫Well, there's a distinction I want to make. 72 00:04:56,790 --> 00:05:01,770 ‫You see, when we have our blueprint here in the content browser, we can double click it, we can open 73 00:05:01,770 --> 00:05:03,750 ‫it up and see its properties. 74 00:05:03,750 --> 00:05:04,020 ‫What? 75 00:05:04,090 --> 00:05:07,150 ‫We're looking at here is the default blueprint. 76 00:05:07,150 --> 00:05:11,140 ‫This contains all of the default information for the blueprint. 77 00:05:11,140 --> 00:05:16,360 ‫But as soon as I drag one out into the level, we now have something called an instance. 78 00:05:16,360 --> 00:05:23,530 ‫So this particular BP -- tank that exists in the world is an instance of BP pond tank. 79 00:05:23,530 --> 00:05:30,010 ‫In fact, we can drag out multiple instances and each of these that exist in the world are instances 80 00:05:30,010 --> 00:05:31,510 ‫of BP pond tank. 81 00:05:31,510 --> 00:05:34,840 ‫This is different than the default blueprint. 82 00:05:35,080 --> 00:05:40,810 ‫So here's a little graph for you to refer to, and we're going to be filling this graph out more as 83 00:05:40,810 --> 00:05:42,520 ‫we learn more specifiers. 84 00:05:42,520 --> 00:05:48,640 ‫So far we've only seen visible anywhere, which you'll see is under both the defaults and the instance 85 00:05:48,640 --> 00:05:49,420 ‫columns. 86 00:05:49,540 --> 00:05:52,120 ‫And it's in the row titled Read Only. 87 00:05:52,120 --> 00:05:57,640 ‫So you can see from this graph that a visible anywhere you property will only be visible. 88 00:05:57,640 --> 00:06:02,260 ‫It won't be editable, but it will be visible on both defaults and the instance. 89 00:06:02,260 --> 00:06:07,510 ‫Whereas visible instance only has read only access but only on the instance. 90 00:06:07,510 --> 00:06:10,540 ‫You can't actually see it on the default blueprint. 91 00:06:10,540 --> 00:06:16,420 ‫And then we learned about edit anywhere which allows us to actually edit that you property on defaults 92 00:06:16,420 --> 00:06:17,530 ‫and the instance. 93 00:06:17,530 --> 00:06:21,730 ‫So that's why it exists in both the defaults and the instance column. 94 00:06:21,730 --> 00:06:27,010 ‫So as a challenge, I would like you to add a variable to the base pond class. 95 00:06:27,010 --> 00:06:32,920 ‫Now put this in the public section and what you're going to do is decide what type of variable you'd 96 00:06:32,920 --> 00:06:38,020 ‫like to add, and it can be anything but make it a basic type, like an integer or a float. 97 00:06:38,170 --> 00:06:44,740 ‫You could even make it an F vector or an F string if you want to just initialize it with a default value 98 00:06:44,740 --> 00:06:46,540 ‫like our other end 30 twos. 99 00:06:46,810 --> 00:06:49,030 ‫And this could be any variable you want. 100 00:06:49,030 --> 00:06:52,990 ‫You can make a speed variable or a stamina variable. 101 00:06:52,990 --> 00:06:54,370 ‫You've got some freedom here. 102 00:06:54,370 --> 00:07:00,820 ‫Now once you've created this variable, decide which access level you want for this and then give it 103 00:07:00,820 --> 00:07:04,440 ‫a you property macro and add the correct specify here. 104 00:07:04,450 --> 00:07:10,210 ‫Now decide whether you want this to be visible only on the instance or on the defaults, or if you want 105 00:07:10,210 --> 00:07:16,210 ‫it to be visible anywhere or edit anywhere, use one of the specifiers we've learned so far and give 106 00:07:16,210 --> 00:07:21,160 ‫this variable the correct specify to go ahead and pause the video and make this variable now. 107 00:07:23,970 --> 00:07:24,690 ‫All right. 108 00:07:24,690 --> 00:07:26,800 ‫So I'm going to go ahead and make a variable. 109 00:07:26,820 --> 00:07:29,250 ‫Now, it's okay if you made something completely different. 110 00:07:29,250 --> 00:07:30,810 ‫This is just for practice. 111 00:07:30,810 --> 00:07:38,100 ‫I'm going to make a float and I'm going to call this speed and I'll initialize speed to say 400 F. 112 00:07:38,700 --> 00:07:45,930 ‫And I think I'd like this speed variable to be editable both on the instance and on the default. 113 00:07:45,930 --> 00:07:52,050 ‫So I'm going to give this a U property macro and make this edit anywhere. 114 00:07:52,050 --> 00:07:54,360 ‫So I'm going to go ahead and compile this. 115 00:07:54,360 --> 00:08:00,180 ‫And back in the editor, I can select one of my base -- tank instances. 116 00:08:00,330 --> 00:08:06,870 ‫And here in the details panel, I can see my speed variable and I can of course edit it here. 117 00:08:06,870 --> 00:08:13,290 ‫And if I open -- tank, here's my speed variable, it's set to 400 and it's editable. 118 00:08:13,290 --> 00:08:19,140 ‫So in summary, we've learned the difference between an instance versus the default of a particular 119 00:08:19,140 --> 00:08:20,220 ‫blueprint class. 120 00:08:20,220 --> 00:08:26,280 ‫We also learned a few new property specifiers, such as Visible Anywhere, Visible, instance only and 121 00:08:26,280 --> 00:08:27,240 ‫edit anywhere. 122 00:08:27,240 --> 00:08:34,050 ‫In the next video, we'll continue learning how to control access to C++ variables in Blueprint using 123 00:08:34,050 --> 00:08:35,880 ‫these new properties specifiers. 124 00:08:35,970 --> 00:08:36,900 ‫I'll see you soon.