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‫Hello and welcome.

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‫In this lecture, we're going to create a gun and we're going to learn how we're going to be architecting

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‫guns for this game so that they are swappable, so that we can have different properties on different

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‫types of guns.

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‫And that's generally how the architectures work in shooters first person or third, let's dive in and

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‫see how it's done.

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‫Okay.

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‫So we haven't checked in on our project plan in a little while.

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‫Whenever we got to the plan, movement is done.

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‫The animation for now is done and the shooting, that is the next thing for us to focus on.

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‫Now, it's a little confusing here because our mesh already appears to have a gun, but actually we

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‫don't want to use this gun.

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‫We want to use it in a different way.

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‫Reason being in a shooter type of game, you often want to be able to switch between weapons or at least

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‫be able to have different characters, have different weapons.

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‫And the easiest way to do that is to architect the gun as a separate thing to the character so that

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‫you can swap them out so that it can be responsible for how it shoots.

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‫If it's a rocket launcher or a shotgun or a rifle, they're going to do things in different ways.

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‫Now, you might say, okay, well, let's create a gun component and we can stick that gun component

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‫underneath our mesh that would work, except that then we lose the modularity that allows us to add

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‫multiple components to the gun.

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‫So what we really want to do is go down the route of having an actor for the gun that is childish to

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‫the shooter character.

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‫Now, this is something we haven't come across before, but it works like this.

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‫You can have a shooter character and a gun as it's child and the shooter character can have multiple

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‫components which are child ID to each other.

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‫So you've got the capsule, we've got the mesh as a child of the capsule at the moment, and the components

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‫of the gun can be child ID to that.

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‫So the mesh gets child ID to the mesh of the character.

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‫And if it's got any other components such as maybe a particle effect at the muzzle of the gun, that

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‫might be added to the mesh.

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‫So you can see that these hierarchies are kind of independent, that you've got the scene components,

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‫the ones that have transforms over on the right, and they can be in a certain hierarchy.

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‫And then the actor hierarchy actually follows the hierarchy of the scene components.

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‫The actors don't have a hierarchy of their own.

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‫This is the bit that takes a little bit of time to get your head around and was a a ha moment when it

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‫clicked for me is that in actual fact there is no hierarchy of actors, there's only a hierarchy of

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‫scene components.

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‫There are actors that own the scene components and so they end up having a hierarchy because their scene

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‫components are related to each other, but they don't actually have a relationship among themselves.

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‫So with that said, to set the context, the first thing we want to go and do is actually create ourselves

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‫a C++ gun actor.

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‫And in this case it's not going to be a pawn or character or anything like that.

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‫It's just going to be a straightforward actor because we don't need any behavior.

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‫You don't need to possess it.

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‫We don't need to do anything.

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‫It's just as simple, simple actor.

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‫So let's go ahead and do that.

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‫In fact, a little challenge for you.

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‫Go ahead and create that C++ actor, something you should be able to do a little mini challenge, attempt

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‫it.

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‫Okay.

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‫And back in, I'm going to do it new C++ class and we don't need to have let's see, actor.

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‫That's the one we want to choose and we're going to go ahead and call this one gun, simple as let's

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‫create that class.

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‫And once that's done, it's going to pop up in your code editor and we don't need to do anything with

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‫it just yet because the first thing I want to do is create a blueprint subclass.

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‫So right click on your class in the content browser and instead of calling it My Gun, I don't know

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‫why it automatically defaults that beep underscore gun.

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‫I'm going to put it in the root of content.

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‫Four.

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‫Now we can do a bit of reorganizing once we've got more classes.

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‫As I've said before, we'll create the Blueprint class.

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‫As you can see, it's completely empty.

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‫It's got this default scene root.

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‫We're going to want to fix that up.

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‫What we want to do is actually add a component in C++ because this is a C++ course.

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‫Let's practice the muscle of adding components in C++.

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‫It also means that we're going to have access to those components from within our C++ code to manipulate

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‫and write our code there.

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‫Now the set up we're going to want is to have a scene root component, which is just going to be a scene

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‫component and then a mesh that's a child of that.

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‫Why do we want that?

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‫Because we want to be able to change the position of the mesh relative to the root of the gun so that

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‫we can basically place the handle in different locations for different meshes.

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‫So if we have different guns, we can make sure they all have this handle in the same place so that

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‫when we attach it to the character's hand, it's going to appear with the handle in the character's

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‫hand.

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‫So how are we going to do that?

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‫We're going to go over to our Visual Studio code, and I'm going to create a private section down here

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‫where we're going to store the new properties for the different components that we're going to come

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‫up with.

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‫So I'm going to create a new property visible anywhere that we want our components to be visible anywhere

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‫because they're pointers.

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‫We don't want to be able to edit the pointers, but we do want to be able to see the properties of those

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‫pointers and be able to.

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‫It those, and that then becomes the purview of the class that we're pointing to.

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‫That then decides what gets shown, what is editable.

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‫So all we want to say here is that it's not the pointer that is editable.

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‫So that's why we're going for visible anyway.

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‫Anyway, a little bit of revision there.

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‫Now we want this to be a you because it's a component, then it's a scene component that we're wanting.

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‫If I can type it correctly, I've seen components and it's a pointer to it and this is going to be our

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‫root component.

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‫Like so and then we're going to want a you property.

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‫Again visible anywhere for our mesh.

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‫The class for the mesh is going to be a new static mesh component because this isn't a skeletal mesh,

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‫it's rigid, it doesn't have any skeleton, any bones.

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‫So want that to be a pointer and this is just going to call the mesh like so.

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‫In fact, I think I need to be a little bit careful here because I think root component already exists

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‫in the parent class for actor.

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‫So I'm just going to call this route instead.

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‫And then we've already got a constructor over in the C++.

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‫We're just going to need to include the appropriate header files here.

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‫Now, a little trick when you're in Visual Studio code is to find out where a header file might be.

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‫You use Control P and you're going to search for.

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‫In this case, we want to know the static mesh.

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‫So static mesh components and we can see that the static mesh components dot h if I go ahead and open

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‫it up and hover over the tab, you can see that it is under this long path.

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‫But the bit that's interesting is that it's under classes, which then we can look up from there.

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‫It's going to be components, static mesh component.

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‫So I can close that tab down and just above our include in fact below that include for our gun, we're

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‫going to do a hash include for the components and then the static mesh component.

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‫Now actually, I've just remembered that the meshes that we've got for some reason aren't actually static

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‫meshes.

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‫I believe they might be skeletal meshes.

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‫You can find this out by going into the asset packs, shoot a game weapons and having a look at these

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‫measures.

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‫And sure enough, if you hover over them, you can see that they are skeletal meshes.

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‫Don't ask me why.

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‫For some reason that's what they are.

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‫So we're going to want to change the type to skeletal mesh in the header file.

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‫So instead of the static mesh, it's going to be use skeletal mesh instead.

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‫And same for the include it's going to be the skeletal.

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‫Mesh components that we want to remember.

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‫There's no you in the header files.

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‫And I believe they're seeing components already included here by default.

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‫So it's time for a challenge to add a mesh component of your own.

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‫We're going to create a root scene component, set it to the root and set it to the root for the class

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‫and create a mesh component and set up the attachment between the two so that the mesh component is

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‫a child of that root seam component.

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‫Pause video and have a go.

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‫Okay, welcome back.

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‫So we're going to go over and set.

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‫First of all, our root, it's going to be a create default sub object of type.

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‫You seen components and then we are going to give it a name which is going to be with the text macro,

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‫we're going to call it the root and finish off with a semicolon.

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‫Then we're going to set it as the root.

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‫So set root components will set it as the root component for the actor.

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‫So set root as the root component.

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‫Good stuff.

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‫Then we're going to want to create our mesh.

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‫So mesh equals create default sub object and it's the you skeletal mesh component that we want as the

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‫class and then the text macro for just going to call it mesh and add a semicolon on the end there.

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‫Then we want to set up attachment.

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‫So it's going to be mesh arrow set up.

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‫Set up attachment and we're going to want to attach to the root like so cool stuff so we can go ahead

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‫and save that and hopefully compile and build and we'll go over in to Unreal and have a look at our

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‫child class.

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‫And sure enough, in here we've got ourselves the root, we've got the sub mesh, we've also got this

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‫default scene root which is hanging around, I think let's restart the editor and see if that just goes

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‫away.

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‫Sometimes when adding components, things can linger around like that and get cached.

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‫And sure enough, if we open up the BP gun blueprints again, you can see that we've just got those

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‫two components.

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‫We've added the root and the mesh, and we probably want to go ahead and change out the mesh for one

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‫of the skeletal meshes from the asset packs from the shooter game.

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‫We've got the rifle, we've got a launcher.

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‫I'm going to choose this one to be the rifle.

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‫So actually calling it a BP gun is a little bit disingenuous.

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‫This should probably be the BP rifle.

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‫So let's go ahead and rename that, go over to the content browser and rename it to BP Rifle or BP Gun,

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‫underscore rifle.

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‫Now call it BP rifle directly.

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‫There you go.

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‫And that has given us a gun.

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‫Now, obviously, now this means that we can have all sorts of properties against this actor, such

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‫as the strength of the weapon, its range and so on and so forth, by creating new properties in C++.

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‫And that is the strength of having this architecture is that the guns can then be a little bit different.

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‫We can have different shooting mechanics for rifles versus snipers versus is RPGs, things like that.

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‫So that's great.

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‫And we can also have different stats so we can have a strong rifle and a weak rifle depending on different

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‫blueprint subclasses.

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‫Cool stuff.

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‫Now in the next lecture, we're going to look at how we're going to actually spawn this gun as a child

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‫of our current character.

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‫I'll see you there.