WEBVTT

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Game Advanced
Prototype version 4

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Hi, everyone

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I am Kim Hyun jin, in charge of the creation of FPS game

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In this lesson, we will implement

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the Damaged and Die states for enemy AI

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and use a navigation system

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to avoid obstacles

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and move towards the destination

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Implementing the damaged and die state functions

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Damaged and Die states

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This time, let's implement

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the Damaged and Die states

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First, let's create the Damaged state

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he player will attack the enemy

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with the left mouse button

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Then, you'll be able to see

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the debris effect like this

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If the enemy

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is chasing the player

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and when it takes damage

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the enemy will briefly stop

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then wait for a certain amount of time

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before deciding whether to continue chasing the player

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stay still,

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or attack,

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and then change its state accordingly

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The player has attacked the enemy

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Then, regardless of the enemy's current state

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it will briefly stop and then decide

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whether to attack, move, or idle

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based on the distance to the player

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After the Damaged state ends,

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It will decide whether to

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transition to the Attack, Move, or Idle state

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In the EnemyFSM script,

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you will create a new function below the AttackDelay

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Since the function will be called

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from a different class and not within EnemyFSM,

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add the public keyword in front of the function

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Next, in the void HitEnemy function,

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it will handle transitioning

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to the damaged state

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Later, when implementing the Die state,

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the HP concept will be involved

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At that time, the code

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in the HitEnemy function will be expanded

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For now, let's just transition to the damaged state

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ChangeState

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It transitions to the Damaged state

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within EnemyState

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Next, let's create a function that will be called

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continuously when in the Damaged state

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under, void Damaged

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This will make the time flow

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If the time exceeds the damage delay time,

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calculate the distance to the player

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If the distance is smaller than the attack range,

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transition to the Attack state

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If not, and the distance is smaller than the detection range,

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transition to the Move state

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Otherwise,

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transition to the Idle state

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The comment we wrote

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is exactly the same as the content in the AttackDelay function

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The difference is

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whether the waiting time is the attack delay time

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or the damage delay time,

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that's all the difference there is

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create a function that takes

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the waiting time as a parameter

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to handle this part

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Below the Damaged function,

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we will create a function

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named void DecideState

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add a parameter

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named float delayTime

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Then, cut all the code

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from AttackDelay

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and move it to the DecideState function

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Paste

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And we will replace the AttackDelay variable

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with the delayTime parameter

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that is passed in

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Let's also modify the comments

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if the time

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becomes greater than the waiting time, we will modify

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Once the writing is complete, go to the AttackDelay function

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and execute the DecideState function you just created

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DecideState

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Open the parentheses and pass

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the desired wait time as an argument

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This should wait for the AttackDelay time

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And the Damaged function should

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also call DecideState

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For the parameter, we should pass

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the time for how long the enemy

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should pause when taking damage

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Since the variable hasn't been created yet,

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let's go up and create a variable for it

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The damage delay time

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public float

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The damage delay time is set to 1.5 seconds

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Then, scroll down and pass

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the damageDelay variable

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inside the parentheses of DecideState

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Then, the following content will be executed all at once

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If we don't create and use

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the DecideState function as we did,

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we would have to write

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such long code under

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both the Damaged function

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and inside the AttackDelay function

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Then, the same code will be duplicated like this

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As this increases,

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it will become very difficult to manage later on

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If this same code is in 10 places,

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we would have to change

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all 10 places just to modify one

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But if you implement it

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as a function like this,

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by only changing the function, the parts that use this function

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will automatically apply the updated content

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So, when you're coding and

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you notice that the same functionality

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is repeated in multiple places

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I hope you'll practice creating functions

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and calling them instead

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Now, we need to continuously

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call the Damaged function

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Go up and under UpdateState,

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execute the Damaged function when in the damaged state

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Now, when the player attacks the enemy with the left mouse button,

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the hitEnemy function will be executed

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to transition to the damaged state

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Go to the PlayerFire script,

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and in the FireRay function, if the collided game object

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is the Enemy game object,

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get the EnemyFSM script

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 from that game object

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and then execute the hitEnemy function

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that we just implemented

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we will add the code below line 4 here

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If the collided object is Enemy,

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let's get the EnemyFSM component

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Execute the hitEnemy function

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from the retrieved component

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if not,

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Then, execute the existing functionality

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this is how it works

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If hitInfo,

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The collision information is stored here

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hitInfo, get the name

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from the collided object's transform

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Here, the name of the

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collided game object is stored

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You can compare the name

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using the Contains function

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It asks,

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Does the name contain Enemy?

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If the name of the game object

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contains Enemy

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it returns true

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otherwise, it returns false

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The enemy we implemented

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has the name Enemy

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If the name is Enemy100

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it will still return true because the name contains Enemy

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This code will return true

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Change the name back to Enemy

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If the collided object is checked as Enemy

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then these two functionalities should be

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implemented within these parentheses

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Since we're getting the EnemyFSM component,

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we will create a variable to store the retrieved component

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I will create it with the name EnemyFSM

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Then, hitInfo,

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I will get the FSM component

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through your transform

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we retrieve it through the component function

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which component to get is,

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write that we are getting

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the EnemyFSM component

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If the collided object

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 contains EnemyFSM,

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store it in the FSM variable

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Next, hey FSM,

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this would be the component we assume

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Execute the hitEnemy function

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from the functions you have

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and then, else, if not,

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Place the existing code

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inside these parentheses

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Save it and then return to the editor

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to run it

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Activate the console window

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After aiming like this,

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when I press the left mouse button,

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In the console that it transitions from Idle to Damage,

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waits briefly,

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and then changes from Damage back to Idle

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Then, when it chases and you shoot,

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you'll see it briefly stop and then

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transition back to Idle

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This time, I'll make it keep moving

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while shooting

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Then, you'll see it briefly stop,

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move again, stop,

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and move again, all functioning properly

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We are currently checking

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the name of the game object

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to determine if the collided object is the Enemy

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Let's try doing this with layers instead

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Select the Enemy game object,

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then in the Inspector,

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under the Layer section,

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change it from Default to Add Layer

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by choosing the dropdown menu

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Next, write Enemy in Layer 6,

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then select the Enemy game object again,

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choose Default, and then

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select the Enemy Layer

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we just added

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Now, let's check

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using the layer value

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instead of the game object's name

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Return to the PlayerFire script,

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and if the collided object is Enemy,

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it is currently being searched by its name

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Instead of this, ask the transform of the collided object,

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What is your game object?

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It will ask if the layer value

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of the collided game object is the same

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what is it the same with?

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There is a struct called LayerMask

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It has a function called NameToLayer

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Open the parentheses, and inside,

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enter the name of the layer we added

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It's Enemy, and currently, there is only one

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It checks if it matches the Enemy Layer

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We set the Enemy game object's

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layer to Enemy only

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That's why only the Enemy game object will

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have the Enemy Layer

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You can also identify specific objects

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through layers like this

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This time, we will implement the Die state

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In the EnemyFSM script, you need to distinguish

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whether the HitEnemy function

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will transition to the damaged state

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or the Die state

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To do this, the Enemy

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must have an HP value

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Let's create global variables related to HP

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We will create two variables

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one for the maximum HP

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and one for the current HP

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Write public float

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and set maxHP as 100

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Next, we will set the current HP

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as public float currHP equals 0

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At the start, let's set the current HP

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to the maximum HP

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By doing this, when the game starts

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the current HP will be

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set to 100

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currtHP equals to maxHP

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Come down to HitEnemy function

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Now, the HitEnemy function will take

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a parameter that specifies how much HP

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should be reduced

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So, let's create

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a float parameter named HitPower

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Since the HitEnemy function has been changed,

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you will see an error like this

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in the PlayerFire script

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why so?

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The HitEnemy function requires a float parameter,

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which is why this error occurs

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So, you will create a global variable

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for the weapon damage in the PlayerFire script

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You will define it as

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public float weaponDamage

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let's set it as 20

284
00:20:57.278 --> 00:21:00.808
And when executing

285
00:21:00.808 --> 00:21:06.260
the HitEnemy function in the Raycast,

286
00:21:06.260 --> 00:21:09.575
pass the weaponDamage value as a parameter

287
00:21:12.699 --> 00:21:16.234
Returning to EnemyFSM,

288
00:21:16.234 --> 00:21:19.454
when the HitEnemy function is called,

289
00:21:19.454 --> 00:21:22.789
the value 20 will be passed

290
00:21:22.789 --> 00:21:26.672
After reducing the HP by that value,

291
00:21:26.672 --> 00:21:33.062
if the HP is greater than 0

292
00:21:33.062 --> 00:21:36.572
it will transition to the Damaged state

293
00:21:36.572 --> 00:21:39.939
If the HP is less than

294
00:21:39.939 --> 00:21:43.339
or equal to 0, it will transition

295
00:21:43.339 --> 00:21:46.719
to the Die state

296
00:21:46.719 --> 00:21:54.748
Reduce the current HP by the hitPower value

297
00:21:57.878 --> 00:22:01.762
If the current HP is

298
00:22:05.653 --> 00:22:11.615
greater than 0,

299
00:22:11.615 --> 00:22:13.835
transition to the Damaged state

300
00:22:16.500 --> 00:22:17.577
if not,

301
00:22:21.260 --> 00:22:25.435
Transition to the die state

302
00:22:25.435 --> 00:22:28.926
If not, it means the current HP is

303
00:22:31.020 --> 00:22:35.036
less than or equal to 0

304
00:22:37.619 --> 00:22:39.278
The current HP is stored

305
00:22:39.278 --> 00:22:42.860
in the CurrHP variable

306
00:22:42.860 --> 00:22:46.819
so CurrHP minus equals

307
00:22:46.819 --> 00:22:49.817
Reduce the HP by the hitPower value

308
00:22:51.660 --> 00:22:52.945
Now, we need to ask

309
00:22:52.945 --> 00:23:00.034
If CurrHP is greater than 0,

310
00:23:00.034 --> 00:23:07.586
transition to the Damaged state

311
00:23:07.586 --> 00:23:09.825
If not, else

312
00:23:11.819 --> 00:23:15.286
Transition to the Die state

313
00:23:15.286 --> 00:23:18.180
using ChangeState

314
00:23:18.180 --> 00:23:20.788
EnemyState and Die

315
00:23:24.412 --> 00:23:27.561
To see the value of the HP reduction,

316
00:23:27.561 --> 00:23:30.540
let's output it to the console

317
00:23:30.540 --> 00:23:31.735
print

318
00:23:35.648 --> 00:23:43.018
The current HP value is CurrHP

319
00:23:48.542 --> 00:23:51.589
Let's play this

320
00:23:51.589 --> 00:23:56.340
Mouse left click to fire

321
00:23:56.340 --> 00:23:58.232
Current HP is 80, right?

322
00:23:58.232 --> 00:24:05.569
As we fire additionally, 60, 40 ,20

323
00:24:05.569 --> 00:24:08.041
This time if I shoot again,

324
00:24:08.041 --> 00:24:10.084
It should transition to the Die state

325
00:24:10.084 --> 00:24:13.118
instead of the Damaged state

326
00:24:13.118 --> 00:24:15.070
if I shoot it

327
00:24:15.070 --> 00:24:18.448
Like this, it transitions to Die state

328
00:24:20.540 --> 00:24:23.387
let's add in a code that makes it

329
00:24:23.387 --> 00:24:27.916
destroyed after 1 second in Die state

330
00:24:29.619 --> 00:24:33.269
After going to ChangeState,

331
00:24:33.269 --> 00:24:35.109
add another case statement

332
00:24:35.109 --> 00:24:36.920
in the switch case statement

333
00:24:36.920 --> 00:24:40.189
case EnemyState and Die

334
00:24:45.219 --> 00:24:46.913
and write Destroy

335
00:24:46.913 --> 00:24:49.292
Destroy myself

336
00:24:49.292 --> 00:24:53.510
So, let's use the lowercase version of the game object

337
00:24:53.510 --> 00:24:55.420
and add a semicolon

338
00:24:55.420 --> 00:24:59.430
I'll have it destroyed it after 1 second

339
00:24:59.430 --> 00:25:00.747
So, 1

340
00:25:03.459 --> 00:25:07.182
Save it and then return to the editor

341
00:25:07.182 --> 00:25:09.580
to run the game

342
00:25:09.580 --> 00:25:14.790
After hitting five times, the enemy will die

343
00:25:14.790 --> 00:25:16.177
five

344
00:25:16.177 --> 00:25:18.979
we can see it gets destroyed after one second, right?

345
00:25:18.979 --> 00:25:23.330
But there is one more issue here

346
00:25:23.330 --> 00:25:28.583
We will shoot five times

347
00:25:28.583 --> 00:25:32.430
Now, I'll shoot a bit faster

348
00:25:32.430 --> 00:25:34.848
pewpewpewpew

349
00:25:34.848 --> 00:25:37.364
It does disappear

350
00:25:37.364 --> 00:25:41.040
Transition Idle state to Die state

351
00:25:41.040 --> 00:25:43.807
because it disappears after 1 second,

352
00:25:43.807 --> 00:25:48.094
It's transitioning from Die to Die, and from Die to Die

353
00:25:48.094 --> 00:25:49.172
repeatedly, right?

354
00:25:49.172 --> 00:25:51.900

And the current HP is

355
00:25:51.900 --> 00:25:55.168
continuously decreasing by the negative value as well

356
00:25:57.366 --> 00:26:00.763
So, this time, if the enemy is in the Die state,

357
00:26:00.763 --> 00:26:05.856
we will prevent any more damage from being applied

358
00:26:09.540 --> 00:26:13.016
Next, go to the EnemyFSM script,

359
00:26:13.016 --> 00:26:17.808
and in the hitEnemy function, you will handle the exception

360
00:26:21.540 --> 00:26:25.718
If the current state is Die,

361
00:26:28.380 --> 00:26:34.629
let's exit the function

362
00:26:37.579 --> 00:26:42.619
let's exit the function

363
00:26:42.619 --> 00:26:44.803
What is it same to?

364
00:26:44.803 --> 00:26:47.808
If it's the same as EnemyState's Die,

365
00:26:50.219 --> 00:26:55.938
I will end the function using the return statement

366
00:26:58.660 --> 00:27:00.754
When the return type is void,

367
00:27:00.754 --> 00:27:03.510
the return statement can be omitted

368
00:27:03.510 --> 00:27:05.648
but it can still be used

369
00:27:05.648 --> 00:27:07.157
So, when used,

370
00:27:07.157 --> 00:27:11.845
it will end the function without

371
00:27:11.845 --> 00:27:14.300
executing the code below

372
00:27:14.300 --> 00:27:16.917
Then, if the state is Die, we wouldn't perform

373
00:27:16.917 --> 00:27:20.859
the operation of reducing the current HP

374
00:27:20.859 --> 00:27:24.576
Based on that, we wouldn't execute

375
00:27:24.576 --> 00:27:27.185
the transition to the Damaged state

376
00:27:27.185 --> 00:27:29.660
or the Die state

377
00:27:29.660 --> 00:27:35.047
Save it and let's quickly test the damage

378
00:27:37.300 --> 00:27:39.363
Now,

379
00:27:39.363 --> 00:27:41.783
we see that the transition

380
00:27:41.783 --> 00:27:44.397
to Die state is called only once

381
00:27:46.770 --> 00:27:51.810
Pathfinding

382
00:27:51.810 --> 00:27:55.468
This time, I let's learn about

383
00:27:55.468 --> 00:27:57.106
pathfinding navigation systems

384
00:27:59.440 --> 00:28:09.557
I will place the enemy behind this wall

385
00:28:11.899 --> 00:28:15.431
When the player approaches the wall,

386
00:28:15.431 --> 00:28:22.014
the enemy should avoid the wall and come around it

387
00:28:22.014 --> 00:28:23.691
and that seems normal

388
00:28:23.691 --> 00:28:29.037
but right now, it's going straight through the wall

389
00:28:29.037 --> 00:28:30.265
Let's go ahead and check

390
00:28:32.979 --> 00:28:34.858
As shown, it goes through the wall

391
00:28:37.180 --> 00:28:43.540
If the enemy were a ghost, it would be fine movement

392
00:28:43.540 --> 00:28:47.171
If that's not the case,

393
00:28:47.171 --> 00:28:50.979
it should avoid obstacles

394
00:28:50.979 --> 00:28:54.993
In Unity, they provide

395
00:28:54.993 --> 00:28:57.580
a navigation system package

396
00:28:57.580 --> 00:28:59.838
that can perform this functionality

397
00:29:02.020 --> 00:29:05.170
Let's give it a try and apply it!

398
00:29:05.170 --> 00:29:10.219
First, we need to add

399
00:29:10.219 --> 00:29:12.633
the navigation system package

400
00:29:12.633 --> 00:29:15.940
Select the Package Manager menu

401
00:29:15.940 --> 00:29:20.245
under the Window tab in the editor's top menu

402
00:29:20.245 --> 00:29:25.639
If you click the drop down just to the right of the plus button

403
00:29:25.639 --> 00:29:30.491
under the Package Manager, you'll see several options

404
00:29:30.491 --> 00:29:35.928
Select Unity Registry from the options here

405
00:29:35.928 --> 00:29:42.804
If you type NAVI in the search bar at the top right,

406
00:29:42.804 --> 00:29:46.739
the AI Navigation package will appear

407
00:29:46.739 --> 00:29:50.226
Select the package and then click Install

408
00:29:53.008 --> 00:29:58.003
Now, using this navigation system,

409
00:29:58.003 --> 00:30:01.626
we will divide the terrain into areas

410
00:30:01.626 --> 00:30:04.659
that are accessible and areas that are not

411
00:30:06.979 --> 00:30:11.360
The terrain in this case refers to

412
00:30:11.360 --> 00:30:16.058
the Wall game object and the Floor game object

413
00:30:16.058 --> 00:30:18.960
So, click the plus button in the Hierarchy window

414
00:30:18.960 --> 00:30:24.219
and add an Create Empty game object

415
00:30:24.219 --> 00:30:28.409
and name it Env

416
00:30:28.409 --> 00:30:32.540
Next, set the position to 0, 0, 0

417
00:30:32.540 --> 00:30:35.081
Right click on the Transform name

418
00:30:35.081 --> 00:30:37.609
and select the Reset menu,

419
00:30:37.609 --> 00:30:39.997
and it will initialize like this

420
00:30:41.939 --> 00:30:46.973
Then, select the Ground and Wall,

421
00:30:46.973 --> 00:30:51.620
and place them under the Env game object

422
00:30:51.620 --> 00:30:53.745
as child objects

423
00:30:56.380 --> 00:31:00.383
Next, we'll add a component

424
00:31:00.383 --> 00:31:03.159
to the Env game object

425
00:31:05.619 --> 00:31:09.515
In the Inspector, click the Add Component button,

426
00:31:09.515 --> 00:31:12.589
then search for Nav

427
00:31:12.589 --> 00:31:18.076
and add the NavMeshSurface component

428
00:31:20.540 --> 00:31:23.364
Next, click the Bake

429
00:31:23.364 --> 00:31:25.276
button at the bottom

430
00:31:27.060 --> 00:31:30.174
Then, the areas that are

431
00:31:30.174 --> 00:31:34.109
highlighted in blue will appear like this

432
00:31:34.109 --> 00:31:36.347
The blue areas represent the regions

433
00:31:36.347 --> 00:31:38.316
that can be navigated

434
00:31:38.316 --> 00:31:42.140
using this navigation system

435
00:31:42.140 --> 00:31:47.979
And the areas that show their original color are

436
00:31:47.979 --> 00:31:52.956
marked as inaccessible regions

437
00:31:52.956 --> 00:31:56.245
There is also an inaccessible area

438
00:31:56.245 --> 00:31:59.649
above the Wall

439
00:31:59.649 --> 00:32:03.949
By setting it up like this,

440
00:32:03.949 --> 00:32:08.109
the areas where the player and enemy are

441
00:32:08.109 --> 00:32:13.579
located will also be marked as inaccessible

442
00:32:13.579 --> 00:32:15.638
If the enemy moves like this,

443
00:32:15.638 --> 00:32:19.470
and there’s nothing in the way but they still can’t pass through,

444
00:32:19.470 --> 00:32:20.707
that wouldn’t be right

445
00:32:24.044 --> 00:32:30.140
So, in the NavMeshSurface we just added,

446
00:32:30.140 --> 00:32:33.976
expand Object Collection menu

447
00:32:33.976 --> 00:32:37.802
and since the collect object here is

448
00:32:37.802 --> 00:32:40.939
set to all game object,

449
00:32:40.939 --> 00:32:43.550
this happens

450
00:32:43.550 --> 00:32:48.339
Select All GameObjects, then open the dropdown

451
00:32:48.339 --> 00:32:51.347
and choose the Current Object Hierarchy menu

452
00:32:51.347 --> 00:32:54.196
After that, click Bake again

453
00:32:55.939 --> 00:33:02.690
Then, only the Wall and Ground game objects

454
00:33:02.690 --> 00:33:05.739
will have their areas set

455
00:33:05.739 --> 00:33:08.971
This option is for setting the area

456
00:33:08.971 --> 00:33:12.217
only for game objects

457
00:33:12.217 --> 00:33:14.678
that have children

458
00:33:17.300 --> 00:33:22.538
Now, select the Enemy game object

459
00:33:22.538 --> 00:33:25.380
The game object that needs to find

460
00:33:25.380 --> 00:33:28.524
the path and move is the enemy

461
00:33:28.524 --> 00:33:34.380
The player is controlled by us, we don't need the game to find a path

462
00:33:34.380 --> 00:33:37.797
In the Inspector, click the Add Component button,

463
00:33:39.718 --> 00:33:44.838
and this time, add the NavMeshAgent component

464
00:33:47.300 --> 00:33:51.029
Through the NavMeshAgent component,

465
00:33:51.029 --> 00:33:56.589
when you set a target position within the blue areas,

466
00:33:56.589 --> 00:34:00.215
the enemy will move to that location

467
00:34:00.215 --> 00:34:02.259
However, if there is an obstacle in front,

468
00:34:02.259 --> 00:34:06.976
the enemy will navigate around it to reach the destination

469
00:34:09.120 --> 00:34:12.675
Now, go to the EnemyFSM script

470
00:34:12.675 --> 00:34:19.210
and create a variable to hold the NavMeshAgent component

471
00:34:19.210 --> 00:34:25.528
The variable for the navigation agent

472
00:34:27.780 --> 00:34:37.820
I'll name the NavMeshAgent variable as agent

473
00:34:37.820 --> 00:34:42.154
To use the NavMeshAgent class,

474
00:34:42.154 --> 00:34:45.260
you need to add the line

475
00:34:45.260 --> 00:34:51.563
using UnityEngine AI, at the top

476
00:34:51.563 --> 00:34:53.686
It usually gets added automatically,

477
00:34:53.686 --> 00:34:55.550
but sometimes it might not be

478
00:34:55.550 --> 00:35:00.884
If you see a red line under NavMeshAgent,

479
00:35:00.884 --> 00:35:05.327
make sure to add that line of code manually

480
00:35:05.327 --> 00:35:15.399
At the start, we will get the NavMeshAgent

481
00:35:20.660 --> 00:35:24.482
by setting, agent equals to, to retrieve it

482
00:35:24.482 --> 00:35:32.107
Use GetComponent and NavMeshAgent inside parenthesis

483
00:35:35.379 --> 00:35:38.725
Since the enemy needs to move,

484
00:35:38.725 --> 00:35:41.260
let's go to the Move function

485
00:35:41.260 --> 00:35:46.689
At this point, we made the enemy move towards the player

486
00:35:46.689 --> 00:35:50.753
Instead of calculating the direction and moving in that direction,

487
00:35:50.753 --> 00:35:53.915
we will command the enemy through

488
00:35:53.915 --> 00:35:57.738
the agent to go to the player's position

489
00:35:59.780 --> 00:36:02.215
So, we will comment out the code for calculating

490
00:36:02.215 --> 00:36:04.668
the direction towards the player

491
00:36:04.668 --> 00:36:07.927
and moving in that direction

492
00:36:07.927 --> 00:36:17.303
Let's tell the agent the destination

493
00:36:17.303 --> 00:36:21.699
The destination here would be the player's position

494
00:36:21.699 --> 00:36:25.741
So, the agent has a function called

495
00:36:25.741 --> 00:36:30.397
SetDestination among its features

496
00:36:30.397 --> 00:36:33.957
Open the parentheses, and inside,

497
00:36:33.957 --> 00:36:36.449
we can insert the position value of the destination

498
00:36:36.449 --> 00:36:41.676
So, we will write the code

499
00:36:41.676 --> 00:36:44.627
so that the player gets the position value

500
00:36:48.013 --> 00:36:50.426
Let's go ahead and save it, then try playing the game

501
00:36:52.340 --> 00:36:54.511
If the player gets closer

502
00:36:54.511 --> 00:36:56.898
unlike before when it went through the wall,

503
00:36:56.898 --> 00:37:00.959
this time the enemy is avoiding the wall

504
00:37:05.501 --> 00:37:07.660
We can see that the enemy is successfully avoiding the wall

505
00:37:10.137 --> 00:37:14.313
However, when the enemy attacks,

506
00:37:14.313 --> 00:37:17.808
it seems to push the player slightly as it moves in

507
00:37:19.699 --> 00:37:21.943
The reason this happens is that

508
00:37:21.943 --> 00:37:28.899
when the enemy is in this state, it will chase the player

509
00:37:28.899 --> 00:37:31.772
We set the destination

510
00:37:31.772 --> 00:37:33.858
using the NavMeshAgent,

511
00:37:33.858 --> 00:37:37.437
and that destination is the player's position

512
00:37:39.340 --> 00:37:40.518
So, the enemy is

513
00:37:42.899 --> 00:37:46.789
 trying to reach that exact position

514
00:37:46.789 --> 00:37:50.630
But since the player and enemy don't overlap,

515
00:37:50.630 --> 00:37:53.559
the enemy ends up

516
00:37:53.559 --> 00:37:58.869
gently pushing the player

517
00:37:58.869 --> 00:38:02.260
while moving towards the destination

518
00:38:02.260 --> 00:38:04.849
And then, after that, the enemy attacks

519
00:38:07.179 --> 00:38:09.356
This shouldn't happen like this

520
00:38:09.356 --> 00:38:12.928
If the enemy enters the attack range,

521
00:38:12.928 --> 00:38:15.216
even if the destination was set to the player's position,

522
00:38:15.216 --> 00:38:20.939
it should stop and perform the attack instead

523
00:38:20.939 --> 00:38:23.048
Let's move to the ChangeState function

524
00:38:25.020 --> 00:38:27.919
When the state changes,

525
00:38:27.919 --> 00:38:30.946
we will stop the agent

526
00:38:32.609 --> 00:38:35.789
Even if the enemy is heading towards the destination,

527
00:38:35.789 --> 00:38:39.226
once the state changes, it will stop moving

528
00:38:40.939 --> 00:38:44.558
Let's stop the pathfinding

529
00:38:46.820 --> 00:38:49.866
Hey agent, among the properties you have,

530
00:38:49.866 --> 00:38:53.969
there's one called isStoped

531
00:38:53.969 --> 00:38:56.538
By setting isStopped to true,

532
00:38:58.540 --> 00:39:00.219
it will stop the pathfinding

533
00:39:03.179 --> 00:39:05.906
Save the changes, return to the editor,

534
00:39:05.906 --> 00:39:10.060
and when you play, the enemy should move

535
00:39:10.060 --> 00:39:12.225
based on the distance, right?

536
00:39:12.225 --> 00:39:15.636
But it doesn't move

537
00:39:15.636 --> 00:39:18.184
It moved before, but now it doesn't

538
00:39:18.184 --> 00:39:21.884
The reason is that when it went to the Move state,

539
00:39:21.884 --> 00:39:24.933
it simply stopped the pathfinding

540
00:39:24.933 --> 00:39:28.283
Even though the destination was set,

541
00:39:28.283 --> 00:39:31.709
it’s not moving because it was

542
00:39:31.709 --> 00:39:33.107
set to stop, so it's not functioning

543
00:39:35.100 --> 00:39:38.958
So, we will change isStopped to false

544
00:39:38.958 --> 00:39:41.893
only in specific states

545
00:39:41.893 --> 00:39:42.406
When?

546
00:39:42.406 --> 00:39:44.550
When it's moving

547
00:39:44.550 --> 00:39:46.546
So, you will add another case

548
00:39:46.546 --> 00:39:49.478
to the switch statement

549
00:39:49.478 --> 00:39:54.629
case Move State

550
00:40:00.283 --> 00:40:04.569
Hey agent, among the properties you have

551
00:40:04.569 --> 00:40:08.060
change the isStoped property to what?

552
00:40:08.060 --> 00:40:10.810
to false

553
00:40:10.810 --> 00:40:14.889
Save and come back to the editor

554
00:40:17.300 --> 00:40:19.986
Go ahead and try playing again

555
00:40:19.986 --> 00:40:25.983
Now, the enemy moves, stops, and then attacks

556
00:40:25.983 --> 00:40:30.728
The enemy moves again, stops, and attacks

557
00:40:30.728 --> 00:40:31.471
repeating the cycl

558
00:40:34.699 --> 00:40:36.508
Being too far away, so it switches to the Idle state

559
00:40:36.508 --> 00:40:39.971
While getting close to the enemy,

560
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I'll try attacking by clicking the left mouse button

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It stops and then comes back again

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00:40:47.145 --> 00:40:48.878
Since the enemy has transitioned to the damaged state,

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it stops, comes back, and then attacks

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00:40:53.899 --> 00:40:57.315
Let's summarize the key points we've learned in this session

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Summary
Implementing Damaged and Die state functions
Damaged
Transition to Damaged
ChangeState EnemyState Damaged

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00:40:58.888 --> 00:40:59.769
The void Damaged function is the same as the AttackDelay function
Call the DecideState function and change the parameter attackDelay to delayTime

567
00:40:59.769 --> 00:41:00.513
If it collides with something
if Physics Taycast ray, out hitInfo
If the collided object is an enemy, get the EnemyFSM component

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Execute the HitEnemy function from the retrieved component
if hitlnfo transform name Contains Enemy

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EnemyFMS fam equals hitlnfo transform GetComponent EnemyFSM fsm HitEnemy
If the collided object is not an enemy, execute the existing code

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00:41:02.108 --> 00:41:02.999
can also use the LayerMask.NameToLayer function
to determine specific objects based on their layer

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00:41:02.999 --> 00:41:04.352
Implementing Damaged and Die state functions
UDie
Set the current HP to the max HP
Decrease the current HP by the hit power

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00:41:04.352 --> 00:41:05.712
If HP is bigger than 0, call the ChangeState function with EnemyState Damaged as the parameter

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00:41:05.712 --> 00:41:06.861
If 0 is bigger than or equals to HP, call the
ChangeState function with EnemyState.Die as the parameter

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If the current state is the Die state, exit the function
if currState equals to EnemyState Die

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00:41:07.941 --> 00:41:09.069
Pathfinding
Navigation System
AI navigation that avoids obstacles and finds a path is provided
NavMeshSurface component divding the terrains

576
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Enemy Object
Add the NavMeshAgent component to the Enemy object
Destination set by the NavMeshAgent is player position
Retrieve the navigation agent

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00:41:09.850 --> 00:41:10.791
agent equals to GetComponent NavMeshAgent
Tells the agent the destination
agent SetDestination player position

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00:41:10.791 --> 00:41:11.739
Stop the pathfinding
agent isStopped equals true
To change the isStopped property to false only in specific states,

579
00:41:11.739 --> 00:41:12.838
To add a case in the ChangeState function using a switch statement
case EnemyState.Move
agent isStopped equals to false
break