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‫Hello and welcome.

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‫In this lecture, we're going to be learning about setting location calling functions in C++ so that

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‫we can bring a cube to a new location when we start playing.

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‫As you can see here, this cube suddenly appeared when we started playing.

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‫Let's dive in and see how functions work in C++.

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‫So let's take a look at how functions translate from Blueprint over into C++, particularly using functions

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‫at this stage.

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‫We'll have a look at how to create our own later on in this section.

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‫So to refresh your memory, this is what a function looks like in Blueprint.

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‫You can see we have a node, we've got input pins on the left, output pins on the right, and we can

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‫plug things like a variable into an input pin to do the same thing in C++.

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‫Looks like this you use again function names have no spaces in them.

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‫So instead of having a set actor location node as separate words, we have it all run together using

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‫camel case and then we have our parentheses.

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‫And inside the parentheses we have a list of inputs and these inputs could be more than one.

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‫You can have them comma separated, but for the first instance we're going to just have one.

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‫And these inputs are actually called arguments.

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‫Don't ask me why I don't want to have an argument about it.

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‫So we are going to have to put these variables in, but you don't have to pass variables.

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‫Variables are just one way of doing it.

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‫You can pass values as well.

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‫So if we had a situation like this where we wanted just to set the location to 1 to 3, we can do that

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‫in C++ as well by using the F Vector constructor directly inside the parentheses for the function.

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‫So that means that we set it to a specific value rather than the value contained inside a variable.

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‫So let's give that a go.

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‫We'll go over to Visual Studio code and we're going to have a look at the Begin play just after we have

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‫updated the My Vector.

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‫I'm going to add a couple of new lines and I'm going to start typing set actor location, make sure

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‫you type it correctly because names have to match exactly in C++, then you open your parentheses and

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‫in here we are going to construct a new F vector value.

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‫So we're going to type F vector open parentheses again.

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‫And in here we are actually passing in arguments to the constructor for F Vector.

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‫So this is very much like calling a function and then passing the value of that function into another

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‫function.

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‫But we'll talk more about that sort of stuff later on.

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‫And what we can do here is type in one, comma two, comma three, and that means that the f vector

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‫one, two, three is going to be passed into set actor location and then we can put a semicolon at the

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‫end of the completed line.

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‫So let's go into unreal.

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‫Let's go ahead and compile the code.

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‫And for us to be able to see the effect of this, we need to go to our moving platform actor and you'll

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‫notice there are actually no components on this actor, which means that it can't actually have a position

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‫because only components can give it a position.

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‫So we can go ahead and add something like a cube to this moving platform actor or go to the ad in the

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‫details pane and we go down to Cube and that gives us a cube and we can go ahead and hit play and see

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‫whether we're able to set this act as location.

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‫We can click on the moving platform and then we can eject using the eject button in the toolbar and

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‫then double click on moving platform.

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‫And you can see it takes us to the moving platform's location.

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‫And with that selected in the outlier or in the scene view, we can have a look at the details pane

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‫and we can see that.

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‫Sure enough, the transform says that its location is one, two, three.

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‫We've set that correctly in C++ code.

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‫Now for this next part, it's going to be just confusing if we are setting the Y value of my vector

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‫from the my x variable.

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‫So let's delete that line and begin play for me.

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‫That's line 19 and I'll delete a few of the extra empty lines there so that we've just got one between

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‫the super big in play and set actor location.

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‫Then I'd like to challenge you to use a variable instead of constructing the f vector in place.

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‫So replace the F vector constructor that we're using.

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‫Update the my vector so that it has a different location.

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‫Can you bring it so that it is closer to the player?

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‫When we hit play, the cube is actually positioned somewhere where the player can see it.

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‫Pause the video and have a go.

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‫Hello and welcome back.

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‫So the way we do this is by removing this F vector and it's parentheses and it's arguments, and that's

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‫what they're called, remember?

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‫And then in as the argument to set actor location, we are going to type my vector.

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‫So it's going to use the value inside the my vector variable to set the actor's location on begin play

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‫when we begin playing.

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‫So let's go into unreal let's stop play for now.

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‫Let's have a look at the location of our third person character.

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‫We can see that there is this is the location here.

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‫What I can actually do, you could copy each of these manually.

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‫You could actually just right click on the location, click copy, go over to your moving platform.

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‫And where we have my vector, we can right click and hit paste and it's going to paste the entire vector

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‫right in there.

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‫So now we know that I'm moving Platform Cube is over here at 000.

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‫But if I hit play, well, actually not very much happens because I forgot to compile.

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‫This is the thing to always remember that we do need to compile any changes to C++.

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‫So we must hit that compile button and only when that is complete will we actually see the changes that

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‫we've made.

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‫So let's go ahead and hit play.

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‫And there you go.

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‫We've got the cube standing right in front of our player.

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‫So we've successfully moved it in begin play using C++ code.

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‫Great stuff.

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‫I'll see you in the next lecture.