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In this lecture, we're going to pick up where we left off last time and create our pathfinding script

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to get our enemies moving.

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So let's jump back into Unity and create our next script.

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Let's right click create a new C-sharp script called Pathfinder.

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And then over in our prefabs, let's attach this pathfinder to our enemy prefab so we can add our component

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and find our Pathfinder script.

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Let's open that Pathfinder script up.

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And what this script is going to do is set our enemy to the first waypoint in our list and then iteratively

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move it towards the next waypoint that it hasn't visited yet.

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Once it reaches the end of the path and there are no more waypoints in our list, we can go ahead and

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destroy our enemy.

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So let's clean up the comments above our start and update to begin with.

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For all variables we're going to need reference to a wave config script will object.

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

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And we're also going to want to store the waypoints for our path.

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So let's create a list of transforms and we'll call it the waypoints.

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And this will be populated from our script object.

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Lastly, let's keep track of which waypoint we're currently on.

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So let's have an integer called Waypoint Index and we'll default that to zero.

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So it starts at the first waypoint in our list.

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In START, we want to populate our list of waypoints so we can say waypoint equals the wave config dot

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get waypoints and then we want to move our enemy to the first waypoint in the path.

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We can do that with transform dot position equals the waypoint at waypoint index dot position.

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Then in update every frame, we want to move closer to the next waypoint in the list.

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So in update, we're going to use a method that we're going to call follow path and then under update.

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Let's actually create this method.

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And in here we want to say that if the waypoint index is less than our waypoint account.

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So if we're not at the last waypoint just yet, then we want to move towards the next waypoint in the

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list.

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To do this, we're going to need to know where we are, where we're going, and how fast we're moving.

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Well, we know where we are with our transform position.

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So let's think about where we're going and create a vector to called target position.

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And we're going to set this equal to waypoint at the waypoint index dot position.

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Next, we want to know how fast we're going.

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So let's create a float called Delta.

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Because this is going to be the distance that we're going to be moving each frame.

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And we can get that from our wave config dot get move speed.

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And to make it frame rate independent, we're going to multiply it by time dot delta time.

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To actually move our enemy.

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We need to set its transform position for this frame and for this we're going to use a method called

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move towards.

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We can find this method if we type vector to move towards.

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And we can see from the tooltip here that it requires three parameters.

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It requires the current position, the target position, and the maximum distance delta.

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And it moves the current point towards the target.

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So our current position is our transform position.

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Our target is going to be our target position.

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So the position of our next waypoint and our maximum distance delta is going to be our delta value that

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we just calculated.

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Finally, once we reached the next waypoint in the path, we're going to need to increment our waypoint

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index.

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And we can do this by saying that if our transform position is equal to our target position, then we

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want to go ahead and take waypoint index and increment it by one.

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Now this is giving us a red squiggly error.

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And if we hover over it, it's saying that it's having trouble checking a vector three our position

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versus a vector to our target position.

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So let's fix that very quickly and we can just change our vector two here into a vector three for our

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target position.

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That removes our red squiggly and our script should now compile.

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But before we go ahead and test it, there's one more thing we need to add here.

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And that's what happens when we get to the end of our path.

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So our if statement will walk us through all of our waypoints, and then if we get to the end, we can

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say else destroy the game object.

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So that will remove our enemy from the game once it reaches the end of the path.

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Now let's go ahead and save our script and jump back into unity.

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We've already preformed our path so we can go ahead and delete that from our hierarchy and then on our

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enemy we need a wave config file.

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So in our waves and paths let's right click go up to create and we should have a wave config file here,

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which I've incorrectly spelt.

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So we'll fix that in just a moment.

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This creates our new wave config, which let's just call it wave zero for now and this needs a path

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prefab which we can drag in and an enemy movement speed which we can leave at five four.

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Now with our config file setup, let's again go and find out enemy prefab.

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And attach our wave config file.

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Now, if we go ahead and hit play, we can see that our enemy nicely moves between each waypoint in

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our path, and when it gets to the end, it gets destroyed.

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So congratulations on making your enemy move.

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And now, while I go ahead and fix my spelling mistake for my wave config file, I think it's time for

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your challenge.

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I want you to go ahead and create at least one new path for the enemies to follow.

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And then I want you to go ahead and create a new wave config file that uses your new path.

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So pause the video now and give that go.

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Okay.

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Welcome back.

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So while you've been away, I've gone ahead and created a new path, which is just a mirror image of

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the path I created earlier.

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And to create a new wave config file, let's go up and create a new wave config with the correct spelling

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this time.

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Let's call this wave one and I'm going to attach my new path.

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Now, if we head back into our scene, we can go ahead and duplicate our enemy for now.

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Attach the new wave that we've just created.

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And if we hit play, we should see two enemies following distinct paths.

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So everything seems to be working great.

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And in the next lecture we're going to expand on what we've done here and start creating those enemy

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waves.

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So I'll see you there.