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In this lecture we're using foreign object of type to access our service effector to DX and to speed

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up our player woo so we can make our jumps a lot more interesting by having a boost in our game.

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So let's get started.

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Let's start by opening up our player controller script.

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Having a look in there, you can see that we've got a mechanism for getting a reference to a component

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that's called get component we're using in here.

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And this is when there's a component that is on the same game object.

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So player controller is on our barrier game object.

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You can see down here we've got our player controller.

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So we use get component.

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If we want to get any of the components we can see in here the rigid body or the transform, the capsule

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collider or the other script we've got on there.

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We can use get component and unity will know, aha, you're looking from within this same game object.

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But what if we have something that is on a different game object?

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So for example, here's Barry game object, here's our level sprite shape, different game object.

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And on this other game object, our level sprite sheet, we have these surface effects are 2D.

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So we want to be able to mess around with this.

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We want to increase or decrease the speed to increase or decrease our character.

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So the way that we can access that from one script or one game object, we can say find object of type

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and find object of type is good if you've only got one of those things in your scene.

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So we've only got one level sprite shape, which means we've only got one surface effector to DX.

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This particular approach wouldn't work if we had many of these.

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So if we're saying find object of type tree and we had a whole bunch of trees, then it would just go

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and grab the first one that it would find and it wouldn't be so effective.

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But we know in our scene we're only going to have one surface effector.

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So let's jump into our player controller script and we'll create ourselves a new variable up the top

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here, which will be of type surface effector to DX and we'll call it service effector to DX as a variable

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small s, so type largest variable small s.

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Now we need to say what's going to be stored in this variable.

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And to do that we'll start with surface effector to DX equals and we'll use find object of type.

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Now one thing you really need to be careful about is there's also a find objects of type.

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That's if we want to define a whole bunch of things or all the particular things of that type, and

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it has an S in there so that can trip you up.

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So we just want find object of type.

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We use our angle braces as we do for our get component.

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And within here we're looking for the surface effector to dx parentheses semicolon that will now when

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we click on play that will go and look for it'll snuffle around in our scene and say, Hey, I'm looking

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for a surface effector to DX.

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There it is right in there.

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And this stage you might be saying, Well, what's the difference between a component and a type?

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Because what we're looking for in here is fine object of type service effector to DX and components

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usually are a type as well.

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So when we add a component, it is a surface effect to 2D component.

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It is a thing that is of type surface effector to DX.

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That's how we can go and find it.

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So likewise, if we're looking to find something that is one of our scripts, if we jump back to Barry,

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if we're looking for a crash detector, we can look for the type of crash detector, because when we

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create this as a class, it is also making it of type crash detector.

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So with that logic, you could also look for something that is of type circle.

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Collider 2D or of type capsule.

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Collider 2D type, rigid body 2D.

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Those things will work as well if you're looking for find object of type.

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But for now we just want this service effector to DX.

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Now what are we going to do with it?

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Well, we want to be able to use this to speed it up and slow it down.

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First of all, I'm just going to tidy up our code a little bit.

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We've got this code in here that essentially is saying Rotate the player.

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So I'm going to create that as a new method that we will call within.

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Update.

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So I'm going to highlight all the way from our if statement down to where our curly braces are lined

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up.

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I'm going to hit control period or control full stop on the keyboard and then extract method.

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This will name it as new method.

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So double click on new method F two and I'm going to rename this to B Rotate player.

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So we don't have all these lines of code just sitting in update that makes update very messy.

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We want to have readability at all times, so rotate player, it's popped in the private keyword.

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I'm going to just remove the private keyword.

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We don't need that at the moment.

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We know that it's private.

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Next up, I want to create a new method which I will call respond to Boost.

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That's a way of saying we're going to boost the player.

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Now we've got the red squiggly line because it doesn't exist.

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So we could double click on it and then hit control period or control full stop and generate this new

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method which we will do.

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We don't want to extract, we want to generate a method.

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So we click on that and it creates the structure for us with a new method we don't need private.

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Once again, I've said that before and we've got respond to Boost.

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And then in here it's just a line that says, hey, you haven't put anything in there yet, so it's

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going to throw an exception just to remind us that we haven't put any code in, so we'll delete that.

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Now you could have just gone and typed void respond to boost.

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Curly brace.

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Curly brace.

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You could do that if you want to.

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You didn't have to go and do the little technique I showed you with the control full stop or control,

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period.

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Now I'm going to give you a little bit of framework in here and then challenge you to finish things

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off.

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I'll just put a comment which is saying, if we push up, then speed up, otherwise stay at normal speed.

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That's what we're trying to do in here.

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So that's going to require if statement, it's going to require our input.

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It's a little bit similar to rotate player, but that's what we're trying to aim for here.

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I'm going to give you a little bit of a hint with a couple of variables we create up at the top.

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I'll pop this under our serialised field float talk amount.

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I'll make a serialize field which will be of type float as well, and we'll name this boost speed and

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I'll initialize that at I think 30 F and then we'll make ourselves another serialized field also of

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Type Float and we will call this base speed and we'll initialize that at probably 20.

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If base speed is well, that's how fast we want to go when we're not boosting and boost.

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Speed is while you got it how fast we want to go when we are boosting.

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So we've got all the structure in here.

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The last little hint I'll give you is we need to access the surface effect two D and change its speed.

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So there we go.

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There's some clues for you.

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So here's your challenge.

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Make the player boost.

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Finish our code so that you can boost.

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In other words, speed up your player by increasing the speed of our effector when the player is pushing

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up on the keyboard.

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So you'll need an if statement and an else statement, you'll need to get the player input.

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So you know when the player is pushing up on the keyboard and you'll need to change the speed of the

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effector.

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So this is your challenge.

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Take that on C back here when you've given it your best shot.

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Okay.

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So we've got a few clues in here.

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Let's start with the sort of shape we've got down below.

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If we've got input, dot get key just as we're doing down below and key code dot up arrow think we'll

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use.

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So just as we've done down below, what do we want to do if that's the case.

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Well, curly braces in this instance, we want to be modifying or changing something to do with our

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service effector to D.

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So I didn't give you all the clues on this, but if you go to your surface effect the two RD and have

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a look here, you can see that there is a field which is called speed.

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So we want to change the speed.

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We want to do exactly as we're doing with our mouse and keyboard here.

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But we do this in our code.

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So our variable surface effect, the 2d dot and I believe there's a speed excellent.

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That's going to equal what will it equal if we're pushing up, it will equal our boost speed, boost

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speed semicolon.

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I could have just had that equal throw in here so I could have gone 30 F like that or just 30.

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But then if we want to change it, we have to come and find the exact spot in our code.

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So by having it serialized, we can find that within our inspector, which makes life a lot easier.

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So if we're pushing up, speed up, but if we just do that once we push up once we'll, you know, will

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stay sped up.

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So we need to say else, which is another way of saying otherwise.

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And in this instance, we don't need to say else.

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If we're just saying if you're doing that, do a thing.

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Otherwise the default, the rest of the time, we want you to do something else so we don't need to

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say ls if the player isn't pushing up arrow, we're just saying otherwise do this thing, prevent our

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curly braces and we will set our surface effects, speed back to our base speed and then semicolon.

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I'll just remove my notes got down here make sure that we're calling respond to boost within update.

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Yes we are click on save back over into unity.

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What I'm going to do just to test that this is working is I'm going to make my speed crazy fast.

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I find that's an easier way as opposed to being like, am I sped up so I'm going to make it 100 in my

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inspector here.

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Let's click on play.

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Cruising, cruising, cruising speed.

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Whoa!

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Woo!

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I think we can conclude that that is working now.

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We'll pop this back to 30 and we'll see if that's the right value for us to have.

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We want to make sure that when we're pushing, we speed up.

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When we stop pushing, we slow down again.

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Yes, we are definitely doing that.

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And does it help going over that jump?

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Oh, that was so excellent.

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That's exactly what I wanted.

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So now you can have the player speed up and do some sweet jumps.

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Woo!

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And I think for me, I'm going to leave it that the player can just push speed whenever they want to.

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They can boost whenever they want to, as opposed to having some sort of time or or some sort of amount

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like boost amount.

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But this is something as you get more confident, you can come back to this project and you can put

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in all sorts of mechanisms.

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You can have some visualization on your screen of how much boost you've got left.

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And when you boost, then it decreases.

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So there's a lot you can do with this.

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You can push yourself, you can challenge yourself to take it further.

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But for now, I'm pretty happy with this implementation where we've used find objective type to access

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the service effector, which is on a different game object from the game object that we're listening

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to, the input from our player so that we go, That's all for this lecture.

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I will see you in the next one.