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‫Welcome back.

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‫So we've already created a new capsule component pointer and forward declared it so we didn't have to

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‫include the header file in base upon h.

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‫It's now time to actually construct a capsule component sub object for our base POM And once we do that,

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‫we're going to set our root component to be the capsule.

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‫So how do we actually construct a you capsule component?

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‫The process is very unreal.

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‫Engine specific unreal engine has create default sub object.

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‫This is a template function.

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‫A template function adapts to the type chosen so we can choose a particular type and create default.

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‫Sub object will adapt to that type.

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‫We pass in the type that we wish to construct into create default sub object.

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‫Unlike a regular function, it has these angle brackets.

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‫This is where we pass in the type to construct.

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‫Now create default sub object also takes an argument in its parentheses.

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‫This is going to be a name that we assign to the sub object.

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‫This is different than the variable name and it's passed in as a string literal.

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‫So here's an example.

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‫Let's say we wish to create a u static mesh component.

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‫So we call create default sub object and end the angle brackets we pass in the type u static mesh component

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‫and in the parentheses we give it a name.

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‫Now you've already seen that for String Literals, you should use the text macro.

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‫So we're passing our string literal in using the text macro here.

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‫Now, as I mentioned, this is an internal name used by Unreal Engine.

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‫There are other functions that use this.

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‫For example, there's a function called get default sub object by name.

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‫It retrieves a sub object belonging to a particular object and you can call it passing in a particular

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‫name and it'll look for the sub object with that chosen name.

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‫So the overall function call to create default sub object looks like this.

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‫The type goes in the angle brackets and the name goes in the parentheses.

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‫Now create default sub object returns the address of the newly created component.

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‫So in our case, if we passed in use static mesh component as the type, then we get the address of

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‫a use static mesh component and we can store that in a pointer since pointers store addresses of things.

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‫So say we create a use static mesh component pointer called mesh.

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‫Then we can take that address returned by create default sub object and store that address in our mesh

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‫pointer.

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‫So now that you know how create default sub object works, you're going to use this to construct a capsule

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‫component object.

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‫You're going to do this in the base PON constructor use create default sub object to construct a capsule

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‫component pass in you capsule component and the angle brackets as the type to construct and pass in

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‫capsule collider wrapped in a text macro in the parentheses.

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‫Pause the video and add this to base pont CP in the constructor now.

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‫Okay.

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‫So we're here in Bass Pond.

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‫CP and we'd like to construct a capsule component.

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‫So we're going to take our capsule comp variable and assign the value returned by create default sub

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‫object.

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‫Now, as we've seen, this template function has angle brackets as well as parentheses, and we saw

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‫that the type goes in the angle brackets, we're going to use U capsule component.

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‫And for the parentheses we're going to use the text macro and we're going to call this capsule collider.

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‫And there we go.

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‫Now we're using you capsule component to construct an object of this type.

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‫And when we use a type, we include its header file.

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‫Now let's see what happens when we attempt to compile.

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‫Now again, you can use live coding or you can compile here in VZ code.

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‫I'm going to be compiling here in VTS code throughout this section.

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‫So you can just know that when I compile I have closed the Unreal Engine editor and I'm just compiling

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‫from here.

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‫I'd like to see the error message here and VTS code now attempting to compile this here.

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‫We get a different error than the one we saw in the last video.

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‫Use of undefined type u capsule component.

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‫This time we're trying to use the U capsule component type here in the CPP file to construct an object.

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‫Here's the error code in case you wish to Google this particular type of error for more information.

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‫So now we've seen two different types of compilation errors in this section of the course, and we know

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‫the cause of this particular error.

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‫We haven't included you capsule component.

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‫Now here's U capsule component in Unreal Engine's documentation and here's the include that we need

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‫for this type.

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‫So I'm going to copy this and paste it here at the top of Base Pond CPP.

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‫Now if I attempt to compile again, compilation is successful, we see no errors.

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‫I'm going to close the terminal now.

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‫So we've created the capsule component.

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‫The next thing I'd like to do is make sure the capsule component is the root.

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‫Now we saw how to assign a component as the root and blueprints by clicking and dragging in C++.

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‫It's also pretty easy.

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‫We simply take that root component variable and assign it the value of capsule comp.

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‫Now we've specified that capsule comp should be the root component.

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‫Let's compile this again.

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‫And now after a successful compilation, I'd like to hop back into the editor.

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‫Okay.

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‫I've opened up the editor and I'm going to take my base --, C++ class and drag one in.

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‫And now check this out.

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‫We see a capsule component.

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‫Now in the world, out liner.

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‫It shows that the base -- that I just dragged in is selected now just above search in the details

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‫panel.

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‫I can drag this down and see all components on this base --.

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‫And all we see is this capsule comp because that's the only component that it has.

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‫So we've now added our capsule component and we see the result of that when we actually add an instance

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‫of this class into the world in the Unreal Engine Editor.

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‫So in summary, we've learned how to construct a capsule component from C++, and we made it the root

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‫component by assigning the value of the root component variable to capsule comp.

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‫In the next video, we're going to add more components to our base in C++ class.

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‫I'll see you then.