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‫Hello and welcome.

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‫In this lecture, we're going to be making our very own scene component for the grabber, and we're

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‫going to print out its rotation so that we can see that it is indeed attached to the camera and the

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‫camera's rotation is affecting its rotation.

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‫Let's dive in and see how this works.

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‫Now, if you remember from seeing the demo, I would like to have a little statue in one of these cells

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‫and to allow us to pick it up and take it over to this alcove for placement.

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‫Now, the problem here is that I don't have that statue and I don't have a way of even knowing if I

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‫am pointing at it when I'm trying to pick it up.

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‫So that is what we're going to aim to try and solve in the next few lectures.

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‫So first of all, let's put a statue in place for us to use.

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‫So I'm going to open the cell door a little bit.

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‫So let's click on one of these cells and I'm going to go down to the door and I'm just going to rotate

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‫it nicely open so that we can get in.

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‫The next thing I'm going to do is it's very dark in here, so I'm going to put a new spotlight here.

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‫So let's go to the quickly add button, go to lights and find a spotlight and drag that in to our scene

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‫and drag it up the wall a little bit so that basically we are alerting the player to the fact that they're,

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‫hey, there's something of interest over in this corner that you might want to pay attention to.

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‫And we're going to go to the select the medieval dungeon folder and search for statue.

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‫And you can see we've got a golden one and we've got a stone one.

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‫I'm going to go for actually probably the gargoyle here and I need to give it some sort of something

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‫at the bottom, because I know that this mesh has has a hole in its bottom.

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‫So if we go and turn it upside down, it's going to look awful because it doesn't actually have a back

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‫side.

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‫So what I'm going to do is I'm going to take this gargoyle and I'm going to turn it well, I'm going

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‫to actually add a mesh underneath it.

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‫So we're going to look for some dirt mesh.

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‫And you can see I've got a little bit of dirt here that I'm going to just take and slap on to the existing

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‫gargoyle statue actor.

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‫So this dirt mound and you can see it's absolutely huge in comparison, but don't worry, we can fix

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‫that with a little bit of scale tool.

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‫So this dirt mound, so I'm going to go ahead and scale this locked in the details pane.

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‫Perhaps I'll start with 0.1 and see how small that is.

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‫And let's actually rotate the entire gargoyle actor so that we can see properly what we're doing.

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‫So have a look at that dirt mound.

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‫The dirt mound needs rotating by 180 degrees.

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‫And then let's use the scale tool to make it a little bit bigger.

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‫I'm just gonna finesse these figures a little bit using the details pane now I'm squashing it right

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‫flat with the scale in the Z and finessed it.

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‫I think just enough that it looks like there's a bottom to that.

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‫And now we can put this gargoyle rotated 90 degrees again and try and place it somewhere in the corner

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‫under this spotlight.

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‫So that's the aim for us to get hold of this mesh.

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‫But how are we going to do it?

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‫We're going to need a special component in order to do this, and we could use an actor component,

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‫but in this case, it's actually going to make more sense to use a scene component.

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‫Let's see y let's go ahead and go to the root of our content folder, clear out the search and open

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‫up our BP player and let's open up the full blueprint editor.

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‫And what we want to do is essentially to have something that tracks around when we're moving our first

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‫person camera.

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‫So as I play in here, you can see that I am looking all around and my camera is also looking all around.

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‫So what I want is something that points in the same direction as my camera.

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‫So the logical thing is to attach a component to this camera which would allow it to automatically rotate

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‫with that first person camera and always be pointing, always having its forward vector pointing in

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‫the forward direction of the camera.

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‫So that's what we're going to do, and that is exactly where we need a scene component, a component

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‫that can attach to other scene components and has a transform, has a location, rotation and scale.

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‫So the way we're going to do this is we're going to go to the add button in the components.

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‫But we could do this another way.

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‫We could also go to our content drawer, go click on C++ classes folder and hit add and hit add new

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‫C++ class.

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‫And then what we can do is we can go and scroll down to where you see it says scene component.

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‫So we're going to make.

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‫You seem component rather than an active component.

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‫And we're going to go ahead and hit next.

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‫Now we're going to call this the grabber because it's a component that's going to be eventually responsible

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‫for figuring out what to grab and then grabbing hold of it so that when we move, the grabber takes

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‫it withers.

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‫So we're going to go ahead and create this class, which takes us over to Visual Studio code with a

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‫grabber and a grab a dot CP and you can see that it's created a U grabber again with this U prefix for

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‫components and it inherits from the you seen components.

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‫That's how we know it is a is a scene component.

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‫Again with that inheritance being the is a relationship.

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‫If we went over to the mover to H, you could see that the inheritance is actually from you act a component.

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‫So that is a a you act a component but otherwise it looks exactly the same.

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‫It's got a big in play, it's got a tick component.

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‫And that's because actually a scene component is an act, a component.

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‫It just adds some more functionality on top.

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‫So now that it's a scene component, we should be able to go over in to our editor, go to our BPE player,

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‫and from here go to add and look for the grabber and the grabber.

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‫Now you see, I had my first person camera selected, so automatically added the grabber as a child

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‫component of that first person camera.

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‫So I'd like to challenge you to print the grabber rotation.

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‫The way we're going to do this is to get the component rotation this time, not the actor's rotation,

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‫because the important thing is actually how this particular component is rotated because it's attached

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‫to the camera.

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‫We're going to convert it to a string using the two compact string function of the F rotator.

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‫This time, because we're not using an F vector for rotation, it does actually have a two compact string

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‫function.

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‫However, then we're going to print that out using the EWI log.

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‫Remember you put a star before a string for strange reasons and then we're going to compile it, test

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‫it out and see does it change the rotation?

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‫Does it move with the camera, pause the video and have a go.

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‫Okay.

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‫Welcome back.

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‫So we're going to be printing this out in tech.

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‫I didn't mention that, but hopefully you figured that out.

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‫And what we're going to do is, first of all, create an F rotator, which is going to store my rotation

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‫and then we're going to get component rotation, parentheses.

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‫And then from this, we need to get an F string, which is going to be the rotation string, which we're

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‫going to do by doing the mini rotation dot.

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‫To compact string parentheses.

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‫Now we're going to type you log and we're going to have the grabber rotation percent sx and then we're

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‫going to remember the star before our rotation string like.

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‫So now let's go ahead and compile this and it looks like that was successful, which is always nice

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‫to see.

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‫And then we're going to go ahead and hit play and have our output log docked in the layout so that I

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‫can see it at all times.

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‫You can see the rotation is indeed being printed out and as I move up you can see my pitch.

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‫The P is changing.

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‫As I turn from side to side, the yaw is changing, but at no point is it kind of tilting from side

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‫to side, which would be the role.

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‫So that's why in the compact representation, the role is always set to zero.

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‫So you can think of it as role pitch and you're like in an airplane.

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‫So it does look like this is updating correctly, as I would expect to with the camera and I'm very

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‫happy with that result.

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‫Great stuff.

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‫So we've seen how we can create our own scene components, how we can attach them to stuff, and how

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‫they have their own notion of rotation, location and scale.

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‫Let's see you in the next lecture.