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In this lecture, we're setting it up so you can pick up the package.

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It disappears.

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You can't pick up another package until you deliver that package.

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Then after you deliver that, you can go pick up the next package and so on.

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So let's get started.

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First step we need to create a couple of extra packages to deliver and scatter them around our map.

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So I'm going to click on a package control DX to duplicate and then move that to a different spot over

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here and then control DX one more time and pop that over here as well.

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Not trying to hide them too much yet we're still in the prototyping phase.

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Side note, I think this circle, we don't need that anymore, so I'm going to delete that.

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So I have three packages floating around in our scene for us to to drive over.

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And if I click on one of these objects, if I want to hide this, I've got a few options.

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First of all, I could just disable the entire object so it just goes away.

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And that's one thing we can do.

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That's totally fine.

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I can also just turn off the Sprite renderer, but then I'd probably also have to turn off the box.

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Collider So these are things that we can do as well.

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We can access these components and say, do the equivalent of what I'm doing here, which is turning

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the checkbox on and off.

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However, for me, I don't want to use this package ever again.

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Once I drive over it, I consider that it's been picked up and it's never going to appear in the game

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ever again.

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I want to do the equivalent of hitting delete and getting rid of that entire thing so it's no longer

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sitting just there.

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I'm going to undo that delete.

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And to do that we can use destroy and I want to show you destroy because destroy is a handy thing to

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know how to actually delete something from your scene and to destroy game objects.

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We call destroy.

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So we call destroy.

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Specifically delete a game object from our scene.

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Destroy when we call, it requires us to tell it.

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In other words, pass in two things and we pass those things in to these parentheses.

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So we have to tell it something.

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What do we need to tell it?

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We need to tell it which game object to destroy and how much time to wait until it is destroyed.

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Now it's actually optional to pass in the delay.

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If you don't have anything in there, then it will just destroy immediately.

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But for the purpose of this challenge, I'd like for you to put in both the game object and the amount

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of time you would like to pause until it is destroyed.

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And so in our case, where we're looking to destroy something other than us, we would need to type,

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destroy, and then in parentheses the monster or whatever the particular thing is that we want to destroy

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dot game object.

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So we need to say it's the game object we're interested in comma and then the delay.

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So in this case I'm saying 0.05 F Now before I give you a challenge, I'll give you one or two other

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clues in here.

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So we need to destroy the package after we pick it up.

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So we'll need to destroy it in a particular place.

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And also, what are we destroying?

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Well, the clue I'll give you is that this other is the game object.

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So when we're getting the information, it's telling us the other thing.

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It's starting off saying, here's the game object.

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In other words, we'll call it other.

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We'll name the game object that you bumped into other.

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So there's a couple of hints for you.

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Here's the challenge.

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So destroy each package that you run over after 1/2.

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Only destroy the one that you run over.

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Don't destroy all of them.

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But after you run over it, use destroy to remove that package so that we can pick them up and not have

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them in the game anymore.

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And I'd also like you to set up a variable and use serialized fields so that we can tune in the inspector

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how long the delay is before the package disappears.

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We don't need to go and find it in the code.

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We can do that from in the inspector and say half a second or 2 seconds we can shoot it from there.

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So there you go.

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There's your challenge.

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Take that on and I'll see you back here when you're done.

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Okay.

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So where do we need to destroy?

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We need to destroy.

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After we've gone and picked up the package, then we say, get rid of that package.

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So I'm going to give myself a new line.

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Destroy in parentheses.

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I need to access other because that's the other thing we're interested in.

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But I need to access the game object.

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You see, the very first property we can get at here is game object.

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So game object, that's the thing I'm destroying because Destroy wants to know the game object and then

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comma, I can type in 0.5 F and then semicolon.

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However, I challenge you not to have this magic number to serialize a variable, so I'm going to jump

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up at the top of my class just above bool serialize field and then it will be of type what it's type

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float.

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We know that because there's an F down the end.

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But if we mouse over here it's looking for destroys looking for a float.

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T you can see just in here gives you a hint object and then float.

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So we'll add a float and we'll call this destroy delay and I'm going to initialize that at 0.5 F, so

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I'm going to give it a starting value.

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It'll be at 0.5 F, then down here instead of 0.5 F, I will call this destroy delay.

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Now let's save that back over into unity.

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We'll make sure everything's hooked up the way we expect it to.

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If we click on Cruisy MC Drive, we'll see.

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Let's see.

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Where is it?

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Down the bottom here we have a destroyed delay currently on 0.5.

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If I click on play, drive over.

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Bup bup bup.

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Yes.

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After we touched it, there was a little bit of a delay, then it disappeared.

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What happens with this one?

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Yeah, it delays as well.

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So they're all set up with that delay.

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This is a good thing.

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Just for me to note briefly, is that once you change something on a script, it applies to all the

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places that script is being referenced.

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So over here the delivery script is places a component and then it's looking at the information within

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the script.

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So you don't need to go and say, change the details of script, their details, the script, their

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details, the script, they're the script.

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If you're pointing to it from this game object, it will update in all those places just in case.

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In case that hasn't been clear, I wanted to point that out.

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Now you can see another problem.

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The player can go and pick up a whole bunch of packages.

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That might be fine.

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You might want to let the player pick up all the packages, but for me, I don't want to do that.

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So let's have a look at our logic here and say, how can we make it that the player can only pick up

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one package at a time?

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Well, what could we do up here saying if the other tag is package?

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So if we drive a a package and something is the case.

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Well, and what do we want to say in here?

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We want to say, well, if you don't currently have a package.

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And how do we write that?

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Well, we could say has package equals equals false.

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That would be one way of writing it.

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However, there's a shorthand way we can write this is by saying in front of a house package, add an

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exclamation mark, which is a way of saying not exclamation mark is not.

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So we're saying here, if other tag is package is true and not has package is true, then do these things

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which like I said before, is another way of saying has package equals equals false.

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So let's check that that works back over into our game.

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We want to pick out one package and then make sure we can't pick up any other packages now that we're

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using our not operator.

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Pick that one up yet?

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Bit of a delay.

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Try to pick this one up.

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I won't let us pick it up because we already have a package.

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Excellent.

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So that's exactly what I wanted to do.

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We can deliver there.

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Pick up the next one.

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Deliver their delivered backwards driving.

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Pick up that one and deliver all of them exactly as we wanted to do.

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Great stuff.

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Okay.

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That's all for this lecture.

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I will see you in the next one.