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Hello again.

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In this lecture we are having a very high level overview of what methods are and we're just going to

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make a capsule spin around by using the transform rotate method.

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Okay, let's get started.

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Hello and welcome.

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We're going to start this lecture off with a challenge right from the get go.

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I want you to start a new 2D project in Unity.

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So open up Unity Hub, start yourself a new project.

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Call it whatever you like.

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Mine will be called delivery driver, but you can call it whatever you like.

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And then once the project is open, want you to add a capsule sprite, and that's going to be our car.

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And then I'd like you to create a C-sharp script or call driver, and then I'd like for you to add the

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script to your capsule sprite as a component.

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So if you're not exactly sure how to do that, we covered that in the very first intro section, but

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it's a case of adding that to your Sprite.

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And then last step, rename the capsule sprite to give you a car, a nifty name.

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Mine's going to be called Cruisy MC Drive.

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You can call yours whatever you like.

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There's your challenge.

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Pause the video and then start the video again once you've completed those steps.

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Hi.

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Okeydokey.

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So I'm in Unity Hub.

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I'm going to click on New.

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I'm using 20, 21.1, etc. I'm going to click on to DX, rename my project to be called Delivery Driver

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and Repos Unity two DX.

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Yep, that's exactly where I want it.

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Click the create button.

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Wait a moment, make myself a cup of tea.

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Go for a walk around the block and when I get back, unity hopefully will be good and ready to go.

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Okay.

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Welcome back.

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I had a nice little walk around the neighborhood, did some push ups, and here I am ready to roll a

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little bit out of breath.

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But good for action.

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I'm going to jump over into my hierarchy right click and select 2D object sprites and find a capsule.

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I'm going to rename it right now.

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Actually, I'm going to do the challenge a little bit.

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Out of order like a rebel.

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What was he called?

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Cruisy Muck drive.

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Kind of makes me want to eat fast food, but hopefully I'm not going to get sued.

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That's probably far enough away from copyright, I think, to be able to call it MC Drive.

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What are we doing next?

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We're creating ourselves a script, so right click down in the assets area, create C-sharp script.

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We will call this driver.

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Now the last step was to click on Cruisy MC Drive and then drag over driver.

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I could have also clicked on add component and searched for driver in there and that would have done

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the same job.

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Now it's time for a little bit of theory.

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Okay.

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We're going to talk about methods.

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What are methods?

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Well, methods are also called functions.

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So you might hear a lot of people referring to them as functions.

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Technically, technically, they're methods, but they're kind of pretty much interchangeable.

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Those two words when it comes to the way that we're using it in unity and C sharp methods execute blocks

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of code that makes our game do things.

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So methods do stuff essentially and we can use the methods already available in unity that some hardworking

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programmer in Unity headquarters has created for us to use.

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Or we can create our own methods and we'll be doing plenty of both of these throughout the entire course.

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The other thing I want you to know in this very, very quick intro to methods is that we do creating

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and calling.

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So when we create a method, we're giving it a name and saying all the things that it should do.

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So a method might be make the thing move forward, make the thing turn around.

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And we also call a method, and that is when we are saying, do the things now, please, let's jump

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back into our game and I'm going to open up my driver script, double click on that.

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That should open up Visual Studio code.

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Just going to tidy things up a little bit here.

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Let's see, I'm going to full screen this actually and make it a little bit bigger.

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So while we're learning things, we're taking up the entire screen just for a moment.

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And you can see right at the very start, we've got our using these are namespaces.

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We'll get to that later on.

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But basically it's saying, hey, you can use all of the things that are contained within here that

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the the unity engineers have given for us.

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We've got public class classes as a way of grouping similar things together.

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And within particular classes we have particular methods we can execute.

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And then we get to the stars of the show, start and update.

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We also have in front of START we have some comments in here.

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You can tell it's a comment because it's in green, but also it has a double forward slashes at the

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start.

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You can do any old comments, you want to hit double fours slash and say this is staff.

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Yay.

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So that's a way to create comments.

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Pretty handy in this case.

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We don't need these particular comments, so I'm just going to delete them for the moment just so we

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can keep this as clean as possible.

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But in general, I don't bother.

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I just leave them in there.

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Okay, so start and update.

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These are methods in particular, they're callbacks.

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Now, we don't need to dig into the depth of what callbacks are, but what I'd like you to understand

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at the moment is unity.

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The unity engine and the unity system of how it executes the game is going to call, start and update

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a little bit in the black box.

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So somewhere Unity is saying, hey, do all the things in start and it's saying do all the things in

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update.

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Now when does it call that?

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When does it say you do all the things that start?

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It's just when we click on the play button, we click on Play Boink, and then anything that's in start

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on any scripts that we have in our scene, it will execute, it will run and say, Do these things now

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and then we have an update.

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Update is called or update is happening or update is doing its stuff, if you will.

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Every single frame that our game is running and we have lots of frames that are running every single

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second.

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So let's jump back into Unity and have a look at what we'd like to do here.

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Now I'm going to click on Cruzi hit W to move Cruzi to the side because I don't like that he's sitting

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right underneath the camera here.

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And what are we going to do in this lecture is rotate cruzi using code.

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And if you have a look, we've played around this before, we've got our position up, down, left,

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right, and we've also got our rotation.

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We want to be rotating on the Z or the Z axis.

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How do I know that?

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Well, I went to X and played around.

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I went to Y and played around and went to Z and I'm going to call it Z and played around.

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And Z was the one who who did it.

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The other way you can look at it is say, well, if we are rotating around this green, it's going to

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rotate around that way.

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If we're rotating around this red or rotate that way, Z is going into the world and it's going to rotate

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around Z.

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How do I know it goes into the world?

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How can we see that?

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Well, a little sneaky trick for you here.

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Up in our scene window, you see a 2D button.

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If you click on that, it will toggle from 2D to 3D.

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I'm going to hold down old and my left mouse button, which will allow me to rotate around.

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And you can see that we have this Z or Z axis that's going into our world.

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And if we rotate around that.

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So I'm going to hit my E key.

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You can see I'm rotating on the blue which rotates around the Z and also just a little sneakiness that

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in Unity two DX games are basically just 3D games where we lock the camera by clicking this 2D button

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here and we are only moving things around on the X and the Y axis.

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Okay.

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The next thing I'll show you is at the moment, if I was to rotate, cruisy, rotate like this, my

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widget is staying at the worlds y up direction and the world's x direction.

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I'm going to undo that move if I come up to the top here and see where it says global.

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If I click from global to local now as I rotate, you'll see that the Green Arrow is staying forwards

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relative to our object because we've rotated the object around.

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The object says, Well, my forwards is now this direction.

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If we rotate around a bit further says, Oh, my forward is that direction.

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That's kind of handy concept for us to have just so we can see which way our car is facing as we drive

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things around.

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So you can see I'm rotating things around here just by clicking and dragging, changing the number in

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here if you will change it.

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Say 45 bump puts on 45 degree angle.

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How do we do that in code?

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Let's return it to zero.

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Jump back over into our script.

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And in here I'm going to do this in code by using a method.

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Okay.

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Which method?

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Well, this method is going to relate to the transform component.

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So I'm going to start by typing in transform with a lowercase t dot.

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And now you see Visual Studio is saying to us, Hey, here's a whole bunch of things that you get if

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you're trying to use something within the transform class.

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So this is a class and we'll talk about classes more later on.

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But we're using the transform class.

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It's also relating to this transform component just here.

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So in transform component, we can do things to position things for rotation, things to scale.

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We want to do something to the rotation.

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And there's a method that comes with unity already, which is called rotate.

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So every time transform, rotate and methods need parentheses at the end of them.

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So these brackets, these round brackets are called parentheses.

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So transform, rotate, and then at the end is a semicolon.

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Now that's pretty good, but it's missing something because what it needs within these parentheses is

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it's saying, Hey, how do you want me to rotate?

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What do you want me to do?

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So this particular method is asking for some arguments.

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It wants to know how much you rotating and it wants to know how much we're rotating on the X, the Y

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and the Z.

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So in here we'll say, Well, for example, let's rotate nothing on the X, let's rotate nothing on

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the Y and let's rotate, say 45 on the Z.

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So that's us calling the rotate method that exists already in unity and putting that with inside the

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start method, which unity is calling all on its very own.

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It's saying, I'll do start when you push the play button.

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Rick No worries.

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And so let's save this up.

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Make sure you save you don't have a dot up here.

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You've got the X back into unity.

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And to see this more clearly, I'm going to grab my game window, hold my left mouse, button down,

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drag it over to the side so that we have the game window and the scene window open at the same time.

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That'll just allow us to see more things, just realign it a little bit, move the cameras around a

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little bit.

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All good.

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Now, when I click on play, what do we expect to have happen?

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Look, it's rotated 45 degrees and you can see our value up here is 45.

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So I'm going to click play to stop proceedings.

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So now we've done that in START.

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That's cool.

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The other thing I want to show you is we can put this exact same thing into update.

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An update is getting cold, like I said, every single frame.

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So let's highlight our transform rotate.

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I'm going to control X to cut that, I'm going to jump down into update, I'm going to control V to

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paste that.

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And this now will be rotating 45 degrees every frame that our computer is able to calculate per second.

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Let's save that back over into unity.

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Now, there's a little thing I want to show you here.

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It might be a little bit hidden on your game window, but if you drag your game window in and find stats,

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just click on stats.

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You'll see at the moment we're getting 743 frames per second.

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Well, you know, I've got a pretty quick computer, but the computer's not really doing anything at

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the moment, so don't celebrate too much.

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Let's click on play and we'll see what happens.

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Okay?

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Whoa, it's out of control at spinning.

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Really quick.

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We have.

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I'll just pause.

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You can pause by the little pause button next to the play button 337 frames per second that we are moving

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45 degrees, which is obviously really, really quick and a bit quicker than we want to.

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So let's jump back over into our script and we'll change from 45 to 0.1.

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And because we've got a decimal place in here and because this is a float, we need to put F at the

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end.

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So Unity knows, oh, it's a float and it doesn't get it confused with something else.

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Now let's save back over into unity.

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Click on the play button and now our object is moving at a more sensible pace.

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But we're using.

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A method to make our object rotate around, which is super cool.

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I'm going to play.

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I'm going to click on stats to get rid of that, put my window back in a sensible position.

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Just a reminder here, we've played around with START, we've played around with Update.

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Both of these are methods that are being called as callbacks by unity, and we ourselves are calling

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the rotate method and we're adding in these particular parameters to make our thing rotate around.

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So there we go.

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There's a quick introduction to methods.

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I will see you in the next lecture.