Develop Reference

How to make Enemy FLIP and ATTACK in Unity2D?

I was following a tutorial for creating an enemy in Unity, but they didn't teach how to flip the enemy in case the Player goes to the other side of the map, oppose to where the enemy is.
So I tried to increase the raycast area, so when the Player collides with it from behind, the enemy will know that it has to flip. But something isn't working, cause it goes fine to the Player when it's facing the left side of the map, but once it flips, it totally stops working, and I can't figure it out why.
Anyone have any idea what should I do?
Here is my code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Skeleton : MonoBehaviour
{
#region Public Variables
public Transform rayCast;
public LayerMask raycastMask;
public GameObject target;
public float rayCastLength;
public float attackDistance; //Mininum distance to attack
public float moveSpeed;
public float timer; // Cooldown b/w attacks
public bool inRange; //check if the player is near
#endregion
#region Private Variables
private RaycastHit2D hit;
private Animator anim;
private float distance; //Distance b/w enemy and player
public bool attackMode;
private float intTimer;
#endregion
void Awake() {
intTimer = timer;
anim = GetComponent<Animator>();
}
void Update() {
if (inRange)
{
hit = Physics2D.Raycast(rayCast.position, Vector2.left, rayCastLength, raycastMask);
}
//When the player is detected
if(hit.collider != null)
{
EnemyLogic();
}
// If it's not inside the raycast
else if(hit.collider == null)
{
inRange = false;
}
// If the player leaves the range
if (inRange == false)
{
anim.SetBool("canWalk", false);
StopAttack();
anim.SetInteger("Idle", 0);
}
}
void OnTriggerEnter2D(Collider2D col)
{
if(col.gameObject.tag == "Player")
{
target = col.gameObject;
inRange = true;
Flip();
}
}
void EnemyLogic()
{
distance = Vector2.Distance(transform.position, target.transform.position);
if(distance > attackDistance)
{
Move();
StopAttack();
}
else if(attackDistance >= distance)
{
Attack();
}
}
void Move()
{
anim.SetInteger("Idle", 1);
anim.SetBool("canWalk", true);
if (!anim.GetCurrentAnimatorStateInfo(0).IsName("attack"))
{
Vector2 targetPosition = new Vector2(target.transform.position.x, transform.position.y);
transform.position = Vector2.MoveTowards(transform.position, targetPosition, moveSpeed * Time.deltaTime);
}
}
void Attack()
{
timer = intTimer; //reset timer
attackMode = true;
anim.SetInteger("Idle", 1);
anim.SetBool("canWalk", false);
anim.SetBool("Attack", true);
}
void StopAttack()
{
attackMode = false;
anim.SetBool("Attack", false);
}
// Detects if the player is on the other side
void Flip()
{
Vector3 rotation = transform.eulerAngles;
if(target.transform.position.x < transform.position.x)
{
rotation.y = 180f;
}
else
{
rotation.y = 0f;
}
transform.eulerAngles = rotation;
}
}

You can flip the enemy using localScale. Do this:
if (Player.transform.position.x < this.transform.position.x)
{
transform.localScale = new Vector3(-1, 1, 1);
}else
{
transform.localScale = new Vector3(1, 1, 1);
}
This detects whenever the player's x position is greater or lower than the enemy and flips the whole object.

Hinge Joint 2d not working properly in my Unity script

I decided to move objects with the mouse. Everything worked out, but I decided to make everything more realistic and added Hingle Joint 2d
And it doesn’t work at all. If you disable ConnectedBody in the code, then the object will attach with its Achor in the wrong direction at all
Ps: I tried to change the value of Mouse to MouseTransofrm
CODE :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DragItems : MonoBehavior
{
public Rigidbody2D selectedObject;
public HingeJoint2D StopCenter = null;
public Rigidbody2D obj;
public Vector2 Mouse;
public Transform Mousetransform;
Vector3 offset;
Vector3 mousePosition;
public float maxSpeed = 10;
Vector2 mouseForce;
Vector3 lastPosition;
void Update()
{
Mouse = Mousetransform.transform.position;
mousePosition = Camera.main.ScreenToWorldPoint(Input.mousePosition);
if (selectedObject)
{
mouseForce = (mousePosition - lastPosition) / Time.deltaTime;
mouseForce = Vector2.ClampMagnitude(mouseForce, maxSpeed);
lastPosition = mousePosition;
}
if (Input.GetMouseButtonDown(0))
{
Collider2D targetObject = Physics2D.OverlapPoint(mousePosition);
if (targetObject)
{
selectedObject = targetObject.transform.gameObject.GetComponent();
offset = selectedObject.transform.position - mousePosition;
}
}
if (Input.GetMouseButtonUp(0) && selectedObject)
{
selectedObject.velocity = Vector2.zero;
selectedObject.AddForce(mouseForce, ForceMode2D.Impulse);
selectedObject = null;
}
}
void FixedUpdate()
{
if (selectedObject)
{
selectedObject.MovePosition(mousePosition + offset);
StopCenter = selectedObject.GetComponent();
StopCenter.enabled = true;
StopCenter.connectedBody = obj;
StopCenter.anchor = Mouse;
}
}
}

Enemy Projectile Script Won't Shoot Closest Object

I Have been trying to figure out how the Enemy doesn't return multiple GameObjects it only returns one.Im not sure whether it is my Bullet script that it allows only one object to return. I'm currently trying to develop a Game with multiple players like Slither.io so I'm not sure if the performance is affected I would like to use (List Function) but dont know where to start and I'm using a later version Unity 2017.3.1f1. Much Appreciated for your help.The scripts are below.
public class RandomAIProjectile
{
private GameObject[] target;
public float speed;
Rigidbody2D bulletRB;
public GameObject explosionEffect;
// Find Targets Section.
void Start ()
{
if (target == null)
target = GameObject.FindGameObjectsWithTag("Player");
for (int i = 0; i < target.Length; i++)
{
bulletRB = GetComponent<Rigidbody2D> ();
Vector2 moveDir = (target[i].transform.position - transform.position).normalized * speed;
bulletRB.velocity = new Vector2 (moveDir.x, moveDir.y);
Destroy (this.gameObject, 2);
}
}
private void OnTriggerEnter2D(Collider2D other)
{
// Decoy Script To Destroy Players.
if (other.gameObject.GetComponent<BlackthronpodDiePlayer>() != null)
{
Destroy (other.gameObject);
Destroy (gameObject);
}
// Damage Effect.
if (other.gameObject.tag == "Player") {
Instantiate (explosionEffect, transform.position, Quaternion.identity);
Destroy(gameObject);
}
// Player (Bullet) Destroy Enemy.
if (other.CompareTag ("Bullet"))
{
Destroy (other.gameObject);
Destroy (gameObject);
}
}
}
Here is the Player Script
public class RandomAIEnemy
{
//Random Movement
public float speed;
public float waitTime;
public float startWaitTime;
public Transform moveSpots;
public float minX;
public float minY;
public float maxX;
public float maxY;
//Enemy AI Shooting
public float lineOfSite;
public float shootingRange;
public float fireRate = 1f;
private float nextFireTime;
public GameObject bullet;
public GameObject bulletParent;
// My Current Player
private BlackthronpodPlayerX playerX;
// Player AI
private GameObject[] player;
public GameObject blood;
Vector3 respawn = new Vector3 (-34f,0,0);
//Additional Info
void FixedUpdate ()
{
EnemyS ();
}
// Use this for initialization
void Start ()
{
//My Player AI Tag.
player = GameObject.FindGameObjectsWithTag("Player");
waitTime = startWaitTime;
//My Current Player Tag.
playerX = GameObject.FindGameObjectWithTag ("Player").GetComponent<BlackthronpodPlayerX>();
//Random Movement Reference
moveSpots.position = new Vector2 (Random.Range (minX, maxX), Random.Range (minY, maxY));
}
//Closest (My Player Including Player AI.)
private bool TryGetClosestPlayer(out GameObject closest)
{
var playersSortedByDistance = player.OrderBy(p => ((Vector2)p.transform.position - (Vector2)transform.position).sqrMagnitude);
closest = playersSortedByDistance.FirstOrDefault();
return closest;
}
void EnemyS ()
{
GameObject closestPlayer = null;
if(TryGetClosestPlayer (out closestPlayer))
{
var distanceFromPlayer = Vector2.Distance (closestPlayer.transform.position, transform.position);
if (distanceFromPlayer <= shootingRange && nextFireTime < Time.time)
{
Instantiate (bullet, bulletParent.transform.position, Quaternion.identity);
nextFireTime = Time.time + fireRate;
}
}
}
// Range And Shooting Boundary For Player Including Player AI.
private void OnDrawGizmosSelected ()
{
Gizmos.color = Color.blue;
Gizmos.DrawWireSphere (transform.position, lineOfSite);
Gizmos.DrawWireSphere (transform.position, shootingRange);
}
// Random Movement (I).
void RandomMove ()
{
//Rotate Movement Of Enemy.
transform.position = Vector2.MoveTowards (transform.position, moveSpots.position, speed * Time.deltaTime);
if (Vector2.Distance (transform.position, moveSpots.position) < 0.2f)
{
if(waitTime <= 0)
{
moveSpots.position = new Vector2 (Random.Range (minX, maxX), Random.Range (minY, maxY));
waitTime = startWaitTime;
} else {
waitTime -= Time.deltaTime;
}
}
}
private void OnTriggerEnter2D(Collider2D collision)
{
// Damage Effect On Enemy.
if (collision.gameObject.tag.Equals ("Player"))
{
Instantiate(blood,transform.position, Quaternion.identity);
}
// My Players Health.
if (collision.CompareTag ("Player"))
{
playerX.health --;
Debug.Log(playerX.health);
Destroy(gameObject);
}
// Player Score Manager.
if (collision.tag == "Bullet")
{
Game.AddToScore(1);
Destroy(gameObject);
}
}
}

Make sure that you have Rigidbody2d attached on your enemy and player. And also, is there any error coming in the code?

CS1001 Identifier Expected in Unity

Basically I've been trying fix this error for ages so I can actually look at thee game in play mode. It is a script for enemy AI who will chase the player around.
The error is at (90,32) which is attempting to transform the enemys vision when they attack the player
The line that is creating the issue is transform LookAt(player);
Any help would be much appreciated.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.AI;
public class EnemyAI : MonoBehaviour
{
public NavMeshAgent agent;
public Transform player;
public LayerMask whatIsGround, whatIsPlayer;
public int Damage = 5;
//Patrolling
public Vector3 walkPoint;
bool walkPointSet;
public float walkPointRange;
//Attacking
public float timeBetweenAttacks;
bool alreadyAttacked;
//States
public float sightRange, attackRange;
public bool playerInSightRange, playerInAttackRange;
private void Awake()
{
player = GameObject.Find("player").transform;
agent = GetComponent<NavMeshAgent>();
}
private void Update()
{
//Check for attack and sight range
playerInSightRange = Physics.CheckSphere(transform.position, sightRange, whatIsPlayer);
playerInAttackRange = Physics.CheckSphere(transform.position, attackRange, whatIsPlayer);
if (!playerInSightRange && !playerInAttackRange) Patrolling();
if (playerInSightRange && !playerInAttackRange) ChasePlayer();
if (playerInSightRange && playerInAttackRange) AttackPlayer();
}
private void Patrolling()
{
if (!walkPointSet) SearchWalkPoint();
if (walkPointSet)
agent.SetDestination(walkPoint);
Vector3 distanceToWalkPoint = transform.position - walkPoint;
//when walkpoint is reached
if (distanceToWalkPoint.magnitude < 1f)
walkPointSet = false;
}
private void SearchWalkPoint()
// Will calculate and random point on the x and z axis
{
float randomZ = Random.Range(-walkPointRange, walkPointRange);
float randomX = Random.Range(-walkPointRange, walkPointRange);
walkPoint = new Vector3(transform.position.x + randomX, transform.position.y, transform.position.z + randomZ);
if (Physics.RayCast(walkPoint, -transform.up, 2f, whatIsGround))
walkPointSet = true;
}
private void ChasePlayer()
{
agent.SetDestination(player.position);
}
private void AttackPlayer()
{
agent.SetDestination(transform.position);
transform LookAt(player);
if (!alreadyAttacked)
{
alreadyAttacked = true;
invoke(nameof(ResetAttack), timeBetweenAttacks);
}
}
private void ResetAttack()
{
alreadyAttacked = false;
}
void OnTriggerEnter(Collider other)
{
Debug.Log("Collison");
if (other.gameObject.tag == "player")
{
if (other.gameObject.GetComponent<Health>() == true)
{
other.gameObject.GetComponent<Health>().TakeDamage(Damage);
}
}
}
}

Identifier Expected in Unity
Means the syntax is incorrect, meaning you've written incorrect code.
transform LookAt(player);
should be
transform.LookAt(player);
whitespace ( ) is not an operator or identifier, and does nothing to the transform. In order to access the properties/methods of the GameObject's transform, you use a dot (.). In this case, you're accessing the transform's LookAt method.

There will be a error:
Change: invoke(nameof(ResetAttack), timeBetweenAttacks); => Invoke(nameof(ResetAttack), timeBetweenAttacks);

How to change player speed with public float from another script

Hey I am trying to change a float when my player collides with a object. I tried many ways of reference but only got null when trying to debug I came up with this so far. I want to get the gameobject that contains the player script meaning the player and after I want to get the component script tankmovement to change the variable in it.
Getting the null reference error in the powerups script line 79 reset function Tank=GameObject.FindWithTag("Player")
using System.Collections.Generic;
using UnityEngine;
public class PowerUp : MonoBehaviour {
public bool boosting = false;
public GameObject effect;
public AudioSource clip;
public GameObject Tank;
private void Start()
{
Tank = GameObject.Find("Tank(Clone)");
TankMovement script = GetComponent<TankMovement>();
}
private void OnTriggerEnter(Collider other)
{
if (other.gameObject.CompareTag("Player"))
{
if (!boosting)
{
clip.Play();
GameObject explosion = Instantiate(effect, transform.position, transform.rotation);
Destroy(explosion, 2);
GetComponent<MeshRenderer>().enabled = false;
GetComponent<Collider>().enabled = false;
Tank.GetComponent<TankMovement>().m_Speed = 20f;
//TankMovement.m_Speed = 20f;
boosting = true;
Debug.Log(boosting);
StartCoroutine(coolDown());
}
}
private IEnumerator coolDown()
{
if (boosting == true)
{
yield return new WaitForSeconds(4);
{
boosting = false;
GetComponent<MeshRenderer>().enabled = true;
GetComponent<Collider>().enabled = true;
Debug.Log(boosting);
// Destroy(gameObject);
}
}
}
void reset()
{
//TankMovement.m_Speed = 12f;
TankMovement collidedMovement = Tank.gameObject.GetComponent<TankMovement>();
collidedMovement.m_Speed = 12f;
//TankMovement1.m_Speed1 = 12f;
}
}
}
Trying to call on my m_Speed float in the player script to boost the speed of my player when he collides with it. How would you get a proper reference since my player is a prefab.
Tank script
using UnityEngine;
public class TankMovement : MonoBehaviour
{
public int m_PlayerNumber = 1;
public float m_Speed = 12f;
public float m_TurnSpeed = 180f;
public AudioSource m_MovementAudio;
public AudioClip m_EngineIdling;
public AudioClip m_EngineDriving;
public float m_PitchRange = 0.2f;
private string m_MovementAxisName;
private string m_TurnAxisName;
private Rigidbody m_Rigidbody;
private float m_MovementInputValue;
private float m_TurnInputValue;
private float m_OriginalPitch;
private void Awake()
{
m_Rigidbody = GetComponent<Rigidbody>();
}
private void OnEnable ()
{
m_Rigidbody.isKinematic = false;
m_MovementInputValue = 0f;
m_TurnInputValue = 0f;
}
private void OnDisable ()
{
m_Rigidbody.isKinematic = true;
}
private void Start()
{
m_MovementAxisName = "Vertical" + m_PlayerNumber;
m_TurnAxisName = "Horizontal" + m_PlayerNumber;
m_OriginalPitch = m_MovementAudio.pitch;
}
private void Update()
{
// Store the player's input and make sure the audio for the engine is playing.
m_MovementInputValue = Input.GetAxis(m_MovementAxisName);
m_TurnInputValue = Input.GetAxis(m_TurnAxisName);
EngineAudio();
}
private void EngineAudio()
{
// Play the correct audio clip based on whether or not the tank is moving and what audio is currently playing.
if (Mathf.Abs(m_MovementInputValue) < 0.1f && Mathf.Abs(m_TurnInputValue) < 0.1f)
{
if (m_MovementAudio.clip == m_EngineDriving)
{
m_MovementAudio.clip = m_EngineIdling;
m_MovementAudio.pitch = Random.Range(m_OriginalPitch - m_PitchRange, m_OriginalPitch + m_PitchRange);
m_MovementAudio.Play();
}
}
else
{
if (m_MovementAudio.clip == m_EngineIdling)
{
m_MovementAudio.clip = m_EngineDriving;
m_MovementAudio.pitch = Random.Range(m_OriginalPitch - m_PitchRange, m_OriginalPitch + m_PitchRange);
m_MovementAudio.Play();
}
}
}
private void FixedUpdate()
{
// Move and turn the tank.
Move();
Turn();
}
private void Move()
{
// Adjust the position of the tank based on the player's input.
Vector3 movement = transform.forward * m_MovementInputValue * m_Speed * Time.deltaTime;
m_Rigidbody.MovePosition(m_Rigidbody.position + movement);
}
private void Turn()
{
// Adjust the rotation of the tank based on the player's input.
float turn = m_TurnInputValue * m_TurnSpeed * Time.deltaTime;
Quaternion turnRotation = Quaternion.Euler(0f, turn, 0);
m_Rigidbody.MoveRotation(m_Rigidbody.rotation * turnRotation);
}
}

Since the TankMovement component you need to access is attached to the GameObject that is colliding with the power, you can get the TankMovement component you need to change by using other.gameObject.GetComponent<TankMovement>():
private void OnTriggerEnter(Collider other)
{
if (other.gameObject.CompareTag("Player"))
{
if (!boosting)
{
// stuff
TankMovement collidedMovement = other.gameObject.GetComponent<TankMovement>();
collidedMovement.m_Speed = 20f;
// more stuff
}
}
}