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‫Hello and welcome.

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‫In this lecture, we're going to be firing off these ball bearings from my current location.

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‫So wherever I am, it can be used to shoot at objects in our scene and already start to create a bit

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‫of wreckage and carnage.

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‫Let's dive in and see how we do this.

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‫So let's quickly review the project plan as it currently stands.

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‫We have already done our playing with physics and spawning our projectiles into the world.

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‫Now what is coming up next is that we need to be aiming those projectiles and ideally starting them

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‫from wherever we're shooting from.

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‫So at the moment when we play the game, that little steel ball drops out, jumps up into the air,

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‫of course.

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‫But it doesn't isn't affected by where I am.

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‫Ideally, this is a kind of first person shooting game.

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‫We should be firing these projectiles out of wherever I'm looking from.

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‫But what is it that is doing the looking here?

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‫Well, let's try and do a little trick that we can do here.

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‫It's called ejecting.

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‫And the way you do this is by holding F eight.

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‫If you type F eight and then fly around, you'll see that I've kind of just stepped out of my body,

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‫that sphere there if I select it.

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‫So the game is still playing at this point, but I'm allowed to go around and select objects.

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‫So what we've got is a object here called a default pawn pa n, which is same as a pawn that you might

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‫use in chess and that hence that little icon.

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‫And what that means is it's the, the piece, the little piece with which we are playing our game.

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‫And it is a representation of physical representation of the player in the game world.

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‫However, when I if I go ahead and stop the game either by hitting escape or by hitting the red button

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‫in the toolbar, you'll notice there is no such thing as a pawn in my scene, nor if I search my outline.

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‫There is nothing called pawn.

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‫So what's going on there?

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‫In actual fact, unreal is by default spawning that pawn into the scene for us and it is placing it

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‫at the location given by an actor in the scene called Player Start.

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‫So if you look in the outline for something called Player Start, you will see that there's this object

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‫that looks a little bit like a capsule and it has got an icon of a controller and a flag.

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‫And what happens is that if I can, I can move that to a different location.

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‫If I want my pawn to start in a different place, you can also rotate it.

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‫If I want to start in a different rotation and I can go ahead and hit play and verify that that has

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‫indeed changed where I start in the game now, why is all of this relevant?

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‫It's relevant because the pawn is the thing that we want to get the location of so that we know where

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‫to put our little pinballs.

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‫So that's what we need to figure out.

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‫So let's go over into our minimal default blueprint, our level blueprint, and see if we can somehow

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‫get hold of this pawn because we can't get a reference to it.

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‫Like we got a reference to the cube because it gets spawned in when we start playing.

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‫So let's right click somewhere in an empty space in the event graph and search for PA n and you'll notice

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‫that one of the nodes that comes up here is called get player pawn.

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‫So if that's not coming up straight away for you, you might need to type, get, play a pawn and then

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‫hit enter and bring it in.

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‫You'll notice that this is one of those nodes that doesn't have an execution pin, but it does have

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‫an input data pin and an output data pin.

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‫And now we understand those data pins a little bit better.

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‫Let's have a look at what that is.

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‫The input data pin, if you hover over it, it says it's an integer.

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‫Okay, so it's looking for a whole number.

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‫And there is a comment underneath it that says the index in the player controller lists, starting with

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‫the local players and then available remote ones.

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‫So this is for multiplayer games, seeing as we're a single player game, the index zero is actually

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‫what we want index zero denoting the first and only player.

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‫And then you can see the return value here is blue.

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‫So I'm guessing it's an object by hover over it.

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‫You can see that it is a pawn object reference.

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‫So it's a pawn object which we know is an actor as well.

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‫Okay.

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‫So now with this pawn object, what could we do with that?

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‫Well, we can drag off of that pin and we can search for what we're looking for is essentially the location

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‫of the player pawn.

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‫So we can search for location and we can see that there is something called a get access.

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‫A location note.

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‫Let's go ahead and select that.

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‫And now you can see that the input has been connected up to the target, which is the input to this

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‫node.

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‫And then there's a new return value which is yellow.

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‫So it's a vector perfect.

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‫This fits with the location that we want in our BFP projectile.

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‫So let's have a go at firing these balls from the player location.

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‫You're going to.

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‫Can you plug in that location?

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‫First of all, in the way that I've got it, I've got got a location and it needs to go into the spawn

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‫node now and also have a look at changing the impulse so that it travels forward so that we can move

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‫around and start shooting at the table and chairs.

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‫Pause the video and have a go.

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‫Okay.

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‫Welcome back.

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‫So, first of all, we're going to drag from the return pin of the actor location node in to the input

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‫for the spawn actor, which is the spawn transform location.

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‫Let's drag that and they're compatible.

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‫They're the same color, they're both vectors so we can make that connection.

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‫Next up, we said we want to change the impulse direction.

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‫At the moment, it's firing straight up.

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‫What I want to do instead, I'm going to cut out of the Z and set it to zero.

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‫So we've got no upwards force.

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‫And instead we know that if we look in our scene, the forwards direction is actually along the x axis.

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‫But notice the x axis is actually pointing in the opposite direction.

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‫So what we need to do is if we had just put 1000 in, these projectiles are going to fire off backwards.

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‫So what we need to do is put in a -1000 and that's going to fire in the opposite direction.

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‫So let's go ahead and hit play and see if we can make this happen.

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‫So I'm going to hit spacebar and you can see it's now firing out of my nose at the table and chairs

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‫and I can get a little bit closer to have that impact, be a little bit more impactful.

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‫I think it's still a little bit weak.

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‫So I'm going to multiply this all by four and go ahead and hit play.

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‫And now we have got ourselves a much more ferocious little pinball that we can fire at objects in our

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‫scene and have a little bit of fun with.

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‫So the last tweak I want to make is that these balls are a little bit light at the moment.

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‫So if we go to our content drawer and double click on the BP projectile, then it will open up the blueprint

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‫editor.

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‫You'll notice that it's got this restricted view at the moment, so you need to click Open Full Blueprint

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‫editor to get back to what we're used to and then click on the viewport tab to see the preview of our

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‫ball bearing.

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‫Now I'm going to click on the static mesh component over in components, then go to the details pane

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‫and have a look for the mass, which I want to override.

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‫At the moment it's a mass of 100 kilos.

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‫I think I need to make this a little bit heavier, so I'm going to multiply this by ten as a starting

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‫point and then we can go ahead and hit play.

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‫And now when I shoot things with this ball bearing, they really do react because it is a pretty heavy

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‫piece of metal.

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‫Great stuff.

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‫So this game is actually starting to become a little bit of fun.

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‫However, we are not able to fire these ball bearings in any particular direction, only forward and

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‫we're going to fix that in the upcoming lectures.

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‫I'll see you there.