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‫Hello and welcome.

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‫In this lecture, we're going to be refactoring our code to make our grab function smaller and more

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‫readable.

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‫And we're going to be using our parameters again.

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‫This time, we're actually going to create a function that takes it as a parameter.

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

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‫So it's generally best practice for functions to try to fit on a single screen.

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‫Now, in my case, my screen is very big, but we are still learning, so it actually makes sense to

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‫have even smaller functions to make things understandable.

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‫And I think this grab function has got too long, so I think we can split it out in two fairly functional

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‫units.

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‫The first one is going to be the bit that does the sweep and does all the calculation of the start and

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‫end vectors and outputs the hit result and whether we have hit or not, the boolean that says whether

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‫we've hit.

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‫And then the second bit is inside the if statement which we can probably leave as the job of grabbing

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‫because that's actually to do with grabbing, right?

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‫We have to wake the rigid body.

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‫We have to grab a component that makes sense to be in a method called in a function called grab.

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‫But this other stuff is a little bit more tangential.

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‫It's more of a utility that we need to pull in.

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‫So I'd like to challenge you to create that utility, get grab able in reach.

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‫That's what I think it should be called.

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‫I think that describes what that lump of code does.

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‫So extract all of that sweep code into a new private function.

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‫Have a think about what its parameters and its return values should be.

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‫Remember, you've got two outputs.

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‫So we've got has hit and hit result.

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‫So you need to think about trying to use an out parameter to make this work.

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‫Now, if you want a little bit of a hint, I'm going to show you what I'm going to put in the header

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‫file in just a second.

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‫If you don't, you can go and pause a video right now.

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‫Otherwise, I'm going to give you the hint.

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‫So we're going to go into grab H and underneath where we've got get physics handle, we are going to

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‫have a Boolean return type to tell us whether something has been we can get something, grab a ball,

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‫let's get grab a ball in reach.

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‫Then we need to give it a parameter which is going to be an out parameter.

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‫So it's going to be a non constant reference to the F hit result.

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‫Put a reference.

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‫Ampersand and then we'll call that the alt hit result like so.

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‫And then I think this isn't going to change anything in our function so we can make it cost as well.

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‫It's a little bonus points if you had already thought of that.

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‫So go ahead, pause the video and try and fill out that function in the C++ file.

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‫Okay.

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‫Welcome back.

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‫So I'm going to copy it.

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‫Go over to the C++.

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‫I'm going to put it underneath our Get Physics Handle component to match the order we've got over in

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‫the header file.

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‫I'm going to add the U grabber in front.

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‫I'm going to indent it correctly.

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‫I'm going to add instead of semicolon the braces and then I'm going to move the code that we've got

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‫over in grab.

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‫So starting at line 53 for me down to 65, I'm going to cut all of that out and we'll replace it with

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‫something in just a second.

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‫I'm going to paste it in to get grab a ball in reach and we've got this hit result that we've created.

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‫What we can do is we can set that out hit result equal to our hit result that we've got here.

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‫We might only want to do that if we've hit.

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‫So we can put that if statement has hit like so and wrap this assignment, the out hit to the hit result

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‫inside the if statement and then we can go ahead and at the end of the function just return has hit

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‫like so now there is an optimization or an improvement that can be made here because we are passing

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‫by reference into the sweep channel and into grab ball in reach.

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‫We don't actually need to create a new hit result in here and then copy it into the hit result.

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‫That's just wasting memory.

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‫What we can do is we can remove the hit result that we're creating inside, get grab a ball in reach

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‫and instead we can just use the reference that we've had passed in to pass directly in to the sweep

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‫single by channel.

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‫So it's actually passing this reference to functions down into the sweep single by channel where it

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‫will get populated and that removes the need for the if statement making this function a little bit

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‫quicker and easier to read.

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‫And in fact, I don't think we even need a variable to store has hit.

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‫We can just go ahead and return.

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‫It's going to be much cleaner to return the get world sweep channel results.

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‫So we're just kind of passing the results from that through back up into get grab able in reach or whoever

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‫is calling it.

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‫So talking of whoever is calling it, we now need to go up into our grab.

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‫We need to create our hit results somewhere.

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‫We have to create it here.

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‫So hit result, this is the one we're going to populate.

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‫We're going to then create a boolean variable which is going to be has hit kind of set that equal to

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‫get grab able in reach.

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‫And we're going to pass in the hit result by reference that we want populated.

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‫And then if we have hit, we're going to go ahead and execute the grabbing code.

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‫Fantastic stuff.

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‫We have moved something in to a function to make this grab function fit on a single screen.

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‫And we've again made use of out parameters, this time creating a function for ourselves that use them

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‫in earnest.

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‫I'll see you in the next video.