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‫Hello and welcome.

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‫In this lecture, we're going to be refactoring our pull trigger so that it's ready for us to add more

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‫code into.

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‫At the moment, it was getting really out of hand, so we're going to refactor it to a small function

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‫like this that's really much more straightforward to read.

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‫Let's dive in and see how to do this refactor.

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‫Okay.

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‫So we want to put some sound into our game and the place we're going to be doing this is in the gun

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‫when we're shooting.

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‫That's the first port of call.

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‫I think a nice kind of shot sound and impact sound would be great.

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‫The only problem is when I came back to our pull trigger function, I noticed that it has got outlandishly

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‫large.

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‫It doesn't fit on one of my screens.

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‫It's also a little bit hard to read and understand where we'd be putting this functionality.

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‫So while we take the effort to actually understand what the functionality is here, maybe it's worth

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‫doing a quick refactor or pulling out some of this stuff into other methods so that it's not so hard

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‫to read.

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‫Now, if you go and have a look at this code and try and figure out what the basic things that it's

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‫doing, then you'll see that a large chunk of this is actually just set up for our line.

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‫Trace this whole chunk from line 28 down to 43.

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‫And what are we doing?

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‫Well, we're getting the owner pawn, then we're checking the getting the owner's controller, then

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‫we're getting the viewport from that, then we're getting the end location based on the max range.

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‫Then we're passing in some hit parameters to ignore stuff.

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‫All of this is just set up for our line trace, so why don't we extract that out into its own function

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‫here?

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‫I'm going to create a new private function down right at the bottom.

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‫After our variables it is going to be bool return because we want to essentially replace this call here

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‫that returns success with one that just gives us the hit result out as well.

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‫So we're going to do this as something I'm going to call a gun trace function and it's going to have

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‫some out parameters here.

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‫Namely, one of them is going to be the hit result.

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‫So hit result, ampersand to make it a reference.

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‫And because it's not a constant reference, we know it's an out parameter.

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‫We call this the hit.

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‫And actually there may be another one that we need here.

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‫Namely, I can see that we've got the rotation is coming out of this chunk of code and in actual fact

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‫we're negating that rotation.

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‫So what we're really interested in is the shot direction.

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‫So maybe that's what we need to go for.

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‫So I'm going to create an F vector out parameter, so F vector ampersand and it's going to be the shot

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‫direction.

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‫These are the two outputs that are going to come from our gun trace.

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‫Now let's go ahead and create the implementation here.

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‫And what we want to do is essentially just copy all of this code into there.

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‫See how it goes.

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‫And we also want to be checking this shot.

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‫Direction.

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‫Take that out there and stick it in just before the end.

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‫Or maybe just here after we've got our player viewport, we can set that the shot direction needs to

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‫be equal to the negative, the rotation.

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‫But it's important to note here that actually we want to be setting not a local variable.

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‫So if you put the type here, it's going to be setting a local shot direction.

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‫We want to delete that so that it is setting the shot direction in the parameters, which actually means

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‫that it's setting the shot direction that we're going to be passing in in the function that calls it.

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‫Same goes for the hit.

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‫We need to remove this local hit so that the hit being passed into line trace single by channel is the

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‫hit that was passed into gun trace.

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‫And then finally, is there anything else is this to do line which is now not needed and also this be

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‫success?

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‫Well, we just need to be returning the result of the line trace signal by channel.

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‫That is going to be whether or not our gun trace has succeeded.

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‫So we've succeeded in making this indentation a little bit less.

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‫We can fit it all on one screen now, and it's a little bit easier to understand that, yes, all of

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‫this is related to getting a gun trace.

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‫We can go up to our gun CP And we can now set our B success up here.

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‫So bool B success, we're going to need to set as the gun trace and we need to pass in some out parameters

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‫here.

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‫So we still need to declare those somewhere if hit result.

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‫It's going to be one of them.

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‫I'm just going to call hit.

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‫And the other one was going to be an F vector called shot direction.

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‫And those are going to be passed in.

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‫So we're going to have the hit first, then the shot direction.

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‫And then semi-colon at the end there.

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‫So that's going to make that just a little bit easier.

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‫However, I'm noticing we also need the owner controller and I don't want the gun trace to be responsible

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‫for the owner controller or forgetting the owner controller.

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‫That doesn't sound like it's the responsibility of a gun trace to do that.

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‫It sounds okay for it to get a hit.

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‫It sounds okay for it to get a shot direction.

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‫But I'm going to draw the line at getting the owner controller.

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‫So for that, I'm going to put it in, put all of this code into another function which both of them

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‫can call.

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‫So that's going to be a function that returns a controller.

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‫Star.

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‫And we're going to call it the get over controller and we can make that a concert.

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‫As we know, it's not meant to change any of the variables on our gun class.

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‫Let's create that implementation.

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‫Just bring in the implementation from gun trace, fix up any indentation if necessary, and we're going

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‫to go ahead and simply return the owner control.

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‫So there's no need to do a null check here.

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‫That null check we do need to do in the function that is using it.

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‫So we'll bring that up there.

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‫We also don't need to set a variable in here.

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‫We can just go ahead and return.

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‫So it's going to be fairly straightforward.

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‫I get on a controller, but not completely.

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‫And then we're going to set the variable in gun trace.

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‫So owner controller is going to be get owner controller like so.

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‫Which we then do a null return to null early return in gun trace, which by the way, it needs to return

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‫a boolean because gun trace is returning a boolean.

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‫So we can go ahead and return false here because if we can't get an owner controller, we can't do a

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‫gun trace.

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‫Therefore we can't possibly hit anything.

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‫And then we also need that owner controller further up.

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‫Where we have our hit actor, we're doing this take damage.

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‫And basically what we want to do here is get the owner controller right in here inside our hit actor.

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‫So if we've hit an actor, we get the owner controller again.

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‫Now, I know there's a little bit of gun tracers calling.

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‫Get a controller and then we're doing it again if we hit an actor.

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‫But that's only going to happen every time we hit an actor.

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‫So I don't mind having that recalculated twice because it's just going to make the code that little

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‫bit more readable without having to store variables and state that could get out of sync.

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‫So there you go.

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‫We're now got the owner controller that we need for take damage and our pull trigger is looking much

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‫better.

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‫So that's it for this lecture.

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‫A quick one.

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‫Just refactoring our pull trigger so that we've got a good base to work from in the next lecture, and

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‫I'll see you there.

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‫Oh, and it looks like I made a little bit of a booboo here in the get owner controller.

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‫If you try and compile it, it won't do anything because this return value is not actually returning

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‫a pointer.

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‫So we want to return null pointer in this case straight away.

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‫Basically we can't get a pawn, then we can't get a controller.

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‫So we return null pointer.