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We now have our enemies moving along our path and being destroyed at the end.

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But this only works for enemies that already exist in the hierarchy.

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So in this lecture, we're going to learn how to instantiate our objects into the scene at runtime.

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Now, this is going to take some modification to our wave config file and our Pathfinder script, and

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we're also going to be writing a new script for our enemy Spanner.

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Let's start off by going into our wave config file.

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So let's head into our scripts folder and then open up our wave config.

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So because in here we're going to want to store all of the enemies that we're going to be instantiating

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as part of our future waves.

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So let's create a new variable.

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It's going to be a serialized filled, and we're going to use a list of game objects.

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So we'll have a list of game objects and we'll call this the enemy prefabs.

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And the general idea is that we're going to be looping through this list in our enemy spawn and generating

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or instantiating each enemy in turn.

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So we're going to need two public getters as well to access the information we need.

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And we're going to start off nice and early with a challenge.

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I want you to go ahead and create a getter called get enemy count.

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And this method is going to return the number or count of the enemies in the enemy prefabs list.

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Our second getter we're going to call get enemy prefab and this is going to pass in an index number

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and we want this to return the enemy prefab at the given index in the list.

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So pause the video now and give that a go.

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Okay.

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Welcome back.

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So let's get on method's return and we're going to start off with our public int get enemy count and

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all this needs to do is return the enemy.

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Prefabs don't count.

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Then for our second getter, this is again going to be public.

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It's going to return a game object.

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So the game object in our list and we're going to call this get enemy prefab.

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We're going to need the index of the game object in our list that we're interested in.

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So we're going to pass in an event called Index.

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And then to retrieve the item from our list, we can just return the enemy prefabs at the given index.

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So with that set up, let's save our script.

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And next we need to create a new script called Enemy Spawn.

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So let's pop back into unity.

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And then in our scripts folder, let's create a new C-sharp script called Enemy Spawn.

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And then open that up.

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Let's clear off the comment above our start method and get rid of the update method entirely because

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we're not going to need that at all.

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And now let's get a reference to our wave config file, which is going to store our enemy list.

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So let's make this a serialized field of type wave config S0 and call it the current wave.

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Then in stock, we're going to call a method that we haven't written yet and we'll call this spawn enemies

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underneath.

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Let's go ahead and write that method.

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And this is going to loop through all of the enemies in our WAV config file and spawn them into the

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world.

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To create objects at runtime, we need to use a method called instantiate.

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And if we look at the tooltip here, we have ten different versions of this instantiate that we can

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use.

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And the reason there are so many is because we can do various different things while we go ahead and

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instantiate our object.

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So at its bare minimum, we're just going to instantiate the object and not worry about any of the other

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parameters.

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And we can do this by taking our current wave dot get enemy prefab and then we can pass it in an index.

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For now, we'll just create the first one in our list, so we'll give it an index of zero.

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And what this will do in its current state is just create that enemy prefab runtime and whatever the

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transform position is of our prefab.

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However, this isn't quite what we want.

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We want the enemy to be instantiated at the start of the path.

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So let's go ahead and add some positional information to our instantiation and we can see from the tooltip

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that we're already getting some hints on what to do.

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Now our starting way point is again stored within our wave script object so we can say current wave

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dot get starting waypoint.

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This is going to return a transform so we can then go ahead and grab the position of that transform.

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Now this is currently giving us an error because there isn't a version of instantiate that just accepts

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these two parameters.

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Whenever we include a position, we're also going to have to include a rotation as well.

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So to save us going off the end of the page, let's break this up into a few different lines.

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And we can see here that the rotation needs to be given as a quotation.

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Now, don't worry too much about what quaternions are.

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This is just a certain way of representing rotations that unity uses behind the scenes.

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And to specify no rotation, we can say Quaternions dot identity.

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Well, notice that with this addition the red squiggles all disappear.

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Now, before we go ahead and test this, we've currently got a wave config serialized filled in our

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enemy spanner and we've also got one in our Pathfinder.

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Now these need to be the same on both scripts.

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So rather than having them as serialized fields and potentially getting into a state where we've either

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forgotten to attach one or we get into a state where we've attached two different wave configs to the

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different components, let's instead try and link them together.

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So in our enemy spawn, let's use this version of our wave config and pass it over to the Pathfinder.

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For this, we're going to need a getter to return the current wave.

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So let's create a public method that returns a wave config, so called get current wave and this is

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going to return our current wave.

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Then over in our path finder we can remove this serialized field to make it completely private, but

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we're going to need reference to our enemy spawn.

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So let's add a new variable of type enemy spawn and we'll call this the enemy spawn.

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Then we need to go ahead and find this object which will exist in our scene.

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We can do this in the awake method by saying enemy spawn equals find object of type enemy spawn.

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Then we need to say that our wave config here is going to be the same wave config from our enemy spawn.

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So down in start above where we're trying to set our waypoints because at this point we've already need

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our wave config set up.

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We can say that our wave config is equal to the enemy spawn top get current wave.

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So a fairly minor change in our pathway into there, but one that should hopefully help us in the long

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run.

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So with all of our scripts saved, let's head back over into unity in our hierarchy.

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Let's right click and create a new empty object called the enemy Spawn.

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Let's reset the transform and then add our enemy spawn a component.

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This is going to need the current wave.

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So in our waves and paths, let's drag over wave zero four now.

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And if we go ahead and just look at our enemy, we'll notice that our Pathfinder no longer has that

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serialized field for the current wave.

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It's now going to be grabbing that directly from this enemy spindle.

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We've just added now over on the waves themselves.

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So in our script or object, we've got this enemy prefabs list.

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This needs to be populated with some enemies to be spawned.

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So let's go ahead and head into our prefabs folder and drag over a single enemy for now.

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Well, in fact, let's just add a few.

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Let's add three in total.

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For now, we're only generating the first one in this list and ignoring the others.

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But in a moment, we're going to look at what happens if we start looping through this list.

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With that all set up, let's go ahead and delete the two enemies that we've got in our scene because

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we're now going to be generating them at runtime with that instantiation method to test things, let's

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hit play.

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And we now have an enemy being created and then destroyed.

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Now if we do that again very quickly.

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And pause.

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We'll say that the enemy wasn't in the same before we hit play.

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But the moment we hit play.

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This enemy gets generated and it has this clone label at the end, meaning that it's being instantiated

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at runtime.

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Now, if we have a lot of enemies being instantiated into our game, then our hierarchy could get fairly

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messy.

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So what we could do is store it inside our enemy spawn.

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This would essentially drag it into here so we could collapse it up.

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And it doesn't have any real effect on the movement of our objects.

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So let's see how we can nest it inside our enemies corner.

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And while we're there, we'll look at looping through all of the enemies in our list and creating all

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of them into our game.

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Back over in our enemy spawn.

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Let's look at nesting our instantiated enemies inside of our enemy spawn.

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We can also do this within our same instantiate method that we're using here.

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So if we add another parameter, we can see that it's asking for a transform for the parent.

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Well, we want the parent to be the enemy spawn of itself so we can just take the transform for this

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object.

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And now, when it's instantiated, it will be put inside of our enemy spawn.

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Next, we want to loop through all of the enemies in our list and create them into the world.

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And we've done the looping several times now, using four and for each loops.

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So have a quick think about which one you think is going to be the most useful in this particular situation.

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Okay.

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I'm not going to give you too long.

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We're actually going to use a four loop for this one.

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And the reason is that we need the index to be passed in to our enemy prefab.

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So we're going to have to keep track of how many times we've gone through this loop.

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So for our loop we can say full int I equals zero because we want to start at the first element in our

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list.

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We want to loop while AI is less than the current wave dot get enemy count.

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So that's why we included that getter earlier on.

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And then we want to increment I by one every time.

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Then with our loop set up inside our instantiation, we want to change this zero to be our iterator.

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Now this is going to do the job we've asked of it, but it's not going to work quite how we want it

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to to say what we mean.

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Let's save our script and then test it in unity.

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And if we hit play and then very quickly hit pause, we can see that our enemies are now contained within

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our enemy spawn, but also notice that they've all generated at exactly the same moment.

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And as it stands, they're all directly on top of one another.

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So we are looping through our list and instantiating all three enemies within our config file, but

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we really don't want them all spawning at exactly the same time and overlapping one another.

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We really want to space these out so that they appear over time.

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We've made some fantastic progress so far though with Instantiating our Enemies runtime, and in the

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next lecture we're going to look at how to space them out over time.

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So I'll see you there.