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Handling automatic weapons in Unity 2D

I am working on simple 2D rouge-like game with weapons, currently my weapon script only handles the shooting of weapon once a left mouse button is clicked. What I am looking for is how to make that shooting happen at some interval. So when a user clicks mouse0 the bullet would shoot but there will be a delay before they can shoot again, as well as if the mouse0 is held then the weapon would shoot at specified firing rate.
Code for my controller:
using UnityEngine;
/*
* This class will be attached to every gun to monitor it's actions on key presses.
* WeaponScript will be called and will be attached to each weapon as well depending on it's type with
* stats. WeaponScript will manage how a weapon behaves instead of this script, this is just a mediator
* so I don't have to write this code in abstract class.
*/
public class WeaponPickUpController : MonoBehaviour
{
//public variables
public float pickUpRange; // range at which a gun will be avaialable to pick up, will probably be constant in the end
public GameObject player = null; // stores player object for it's rb component
public Weapon weaponScript = null;
//protected variables
//private variables
private readonly KeyCode _dropKey = KeyCode.Q; // todo: replace to read from config some day
private readonly KeyCode _pickUpKey = KeyCode.E; // todo: replace to read from config some day
private readonly KeyCode _shootKey = KeyCode.Mouse0; // todo: replace to read from config some day
[SerializeField] private bool _equiped = false; // todo: remove serialize field
// Start is called before the first frame update
void Start()
{
// todo: init variables safely here, also perhaps set variable on save file
}
// Update is called once per frame
void Update()
{
var distanceFromPlayer = Vector2.Distance(player.transform.position, this.transform.position);
//Debug.Log(distanceFromPlayer);
// short circuit this if gun is equiped
if (!_equiped && distanceFromPlayer < pickUpRange && Input.GetKeyDown(_pickUpKey)) // todo: a range check here
{
PickUpWeapon();
}
//short circuit this if it is not equiped
if (_equiped && Input.GetKeyDown(_dropKey))
{
DropWeapon();
}
// short circuit if not equiped
if (_equiped && Input.GetKeyDown(_shootKey))
{
weaponScript.Shoot();
}
}
private void PickUpWeapon()
{
_equiped = true;
weaponScript.GetEquiped();
}
private void DropWeapon()
{
_equiped = false;
weaponScript.GetUnequiped();
}
}
Code for Weapon:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Weapon : MonoBehaviour
{
public float damage = 10f;
public float projectileSpeed = 1f;
public float damageBonus = 0f;
[SerializeField] private Rigidbody2D _rb = null;
[SerializeField] private GameObject _player = null;
[SerializeField] private Transform _firePoint = null;
[SerializeField] private GameObject _projectile = null;
//Only called once
private void Start()
{
// load form config
}
// todo: make abstract since this is a superclass
public void Shoot()
{
GameObject projectile = Instantiate(_projectile, _firePoint.position, _firePoint.rotation); // instantiate projectile and make it a child of weapon
Rigidbody2D projectile_rb = projectile.transform.GetComponent<Rigidbody2D>();
//projectile_rb.AddForce(_firePoint.up * projectileSpeed, ForceMode2D.Impulse);
projectile_rb.velocity = _firePoint.up * projectileSpeed;
}
public void GetEquiped()
{
Transform playerTransform = _player.transform;
float playerLocalOffset = _player.GetComponent<BoxCollider2D>().size.x;
_rb.isKinematic = true; // makes this move with the player
transform.rotation = playerTransform.rotation;
transform.SetParent(playerTransform);
transform.localPosition = new Vector3(-playerLocalOffset, 0, playerTransform.position.z);
}
public void GetUnequiped()
{
_rb.isKinematic = false; // makes it dynamic agian
transform.SetParent(null);
transform.position = new Vector3(transform.position.x, transform.position.y, 2);
}
}

Well in your weapon you could have a cooldown like e.g.
public class Weapon : MonoBehaviour
{
...
// How much time has to pass between two bullets fired?
[SerializeField] private float bulletDelay = 0.1f;
// A flag indicating whether this weapon can currently shoot
private bool canShoot = true;
public void Shoot()
{
// while the flag is false do noting, you can't shoot now
if(!canShoot) return;
// ... Your shoot stuff here
// set the flag because you just shot
canShoot = false;
// Invoke the CooldownFinished method after bulletDelay has passed
Invoke(nameof(CooldownFinished),bulletDelay);
}
private void CooldownFinished()
{
canShoot = true;
}
}
If you rather want to provide a "rate" then simply invert
[SerializeField] private float bulletsPerSecond = 10f;
and then
Invoke(nameof(CooldownFinished), 1f / bulletsPerSecond);

Multiple instance of Game Object while setting Game object Active

I am newbie to Unity 3D. I have created a game object(A missile) at position x:-1 y:-3 z:0 Added a component script which moves the ball in upward direction. Saved it as a prefab. Then deleted the Game object from the scene.
Component Script used
using UnityEngine;
public class Missile : MonoBehaviour
{
[SerializeField] protected Rigidbody2D rb;
public float speed = 4;
void Start()
{
Invoke("Object", 2.0f);
}
void Object()
{
float x = Random.Range(-2.0f, 2.0f);
float y = -5.0f;
rb.MovePosition(new Vector3(x, y, 0));
Debug.Log("Position of Rigid Body: " + rb.position);
rb.velocity = Vector2.up * speed;
}
virtual protected void Die()
{
Destroy(gameObject);
}
}
Invoked a script which takes prefab as input parameter and spawns the Game object at random position & moves up as per the script component of missile. I need the missile to trigger at random location, but the missile is getting triggered both at position x:-1 y:-3 z:0(Game object position) & some random location. How can I avoid the Game object position while spawning
Script used to invoke the prefabs
using UnityEngine;
using System.Collections;
using TMPro;
public class MissileSpawnner : MonoBehaviour
{
[SerializeField] GameObject[] missilePrefabs;
[SerializeField] int missileCount;
[SerializeField] float spawnDelay;
GameObject[] missiles;
#region Singleton class: MissileSpawnner
public static MissileSpawnner Instance;
void Awake()
{
Instance = this;
}
#endregion
void Start()
{
PrepareMissiles();
StartCoroutine(SpawnMissiles());
}
IEnumerator SpawnMissiles()
{
for (int i = 0; i < missileCount;i++)
{
Debug.Log("Object set as active");
missiles[i].SetActive(true);
yield return new WaitForSeconds(spawnDelay);
}
}
void PrepareMissiles()
{
missiles = new GameObject[missileCount];
int prefabsCount = missilePrefabs.Length;
for (int i = 0; i < missileCount; i++)
{
missiles[i] = Instantiate(missilePrefabs[Random.Range(0, prefabsCount )]);
missiles[i].SetActive(false);
}
}
}

Change this:
missiles[i] = Instantiate(missilePrefabs[Random.Range(0, prefabsCount )]);
to
missiles[i] = Instantiate(missilePrefabs[Random.Range(0, prefabsCount )], <vector3position>, <quaternionrotation>);
and you will specify its position and rotation, just replace vector3position with a vector3 of your choosing and quaternionrotation with a quaternion rotation of your choosing. You can use Quaternion.Identity if you don't want any rotation. You can also add a parent if you choose as well.
missiles[i] = Instantiate(missilePrefabs[Random.Range(0, prefabsCount )], <vector3position>, <quaternionrotation>, <transformparent>);
Just replace transformparent with the gameobject you want to be the parent of the bullet, if this override can prove useful to you.
More reading on Object.Instantiate
https://docs.unity3d.com/ScriptReference/Object.Instantiate.html

Unity3D playing sound when Player collides with an object with a specific tag

I using Unity 2019.2.14f1 to create a simple 3D game.
In that game, I want to play a sound anytime my Player collides with a gameObject with a specific tag.
The MainCamera has an Audio Listener and I am using Cinemachine Free Look, that is following my avatar, inside the ThridPersonController (I am using the one that comes on Standard Assets - but I have hidden Ethan and added my own character/avatar).
The gameObject with the tag that I want to destroy has an Audio Source:
In order to make the sound playing on the collision, I started by creating an empty gameObject to serve as the AudioManager, and added a new component (C# script) to it:
using UnityEngine.Audio;
using System;
using UnityEngine;
public class AudioManager : MonoBehaviour
{
public Sound[] sounds;
// Start is called before the first frame update
void Awake()
{
foreach (Sound s in sounds)
{
s.source = gameObject.AddComponent<AudioSource>();
s.source.clip = s.clip;
s.source.volume = s.volume;
s.source.pitch = s.pitch;
}
}
// Update is called once per frame
public void Play (string name)
{
Sound s = Array.Find(sounds, sound => sound.name == name);
s.source.Play();
}
}
And created the script Sound.cs:
using UnityEngine.Audio;
using UnityEngine;
[System.Serializable]
public class Sound
{
public string name;
public AudioClip clip;
[Range(0f, 1f)]
public float volume;
[Range(.1f, 3f)]
public float pitch;
[HideInInspector]
public AudioSource source;
}
After that, in the Unity UI, I went to the Inspector in the gameObject AudioManager, and added a new element in the script that I named: CatchingPresent.
On the Third Person Character script, in order to destroy a gameObject (with a specific tag) when colliding with it, I have added the following:
void OnCollisionEnter(Collision other)
{
if (other.gameObject.CompareTag("Present"))
{
Destroy(other.gameObject);
count = count - 1;
SetCountText();
}
}
It is working properly as that specific object is disappearing on collision. Now, in order to play the sound "CatchingPresent" anytime the Player collides with the object with the tag, in this case, Present, I have tried adding the following to the if in the OnCollisionEnter:
FindObjectOfType<AudioManager>().Play("CatchingPresent");
But I get the error:
The type or namespace name 'AudioManager' could not be found (are you
missing a using directive or an assembly reference?)
AudioManager.instance.Play("CatchingPresent");
But I get the error:
The name 'AudioManager' does not exist in the current context
As all the compiler errors need to be fixed before entering the Playmode, any guidance on how to make the sound playing after a collision between the player and the gameObject with the tag Present is appreciated.
Edit 1: Assuming that it is helpful, here it goes the full ThirdPersonUserControl.cs:
using System;
using UnityEngine;
using UnityEngine.UI;
using UnityStandardAssets.CrossPlatformInput;
namespace UnityStandardAssets.Characters.ThirdPerson
{
[RequireComponent(typeof (ThirdPersonCharacter))]
public class ThirdPersonUserControl : MonoBehaviour
{
public Text countText;
public Text winText;
private int count;
private ThirdPersonCharacter m_Character; // A reference to the ThirdPersonCharacter on the object
private Transform m_Cam; // A reference to the main camera in the scenes transform
private Vector3 m_CamForward; // The current forward direction of the camera
private Vector3 m_Move;
private bool m_Jump; // the world-relative desired move direction, calculated from the camForward and user input.
private void Start()
{
count = 20;
SetCountText();
winText.text = "";
// get the transform of the main camera
if (Camera.main != null)
{
m_Cam = Camera.main.transform;
}
else
{
Debug.LogWarning(
"Warning: no main camera found. Third person character needs a Camera tagged \"MainCamera\", for camera-relative controls.", gameObject);
// we use self-relative controls in this case, which probably isn't what the user wants, but hey, we warned them!
}
// get the third person character ( this should never be null due to require component )
m_Character = GetComponent<ThirdPersonCharacter>();
}
private void Update()
{
if (!m_Jump)
{
m_Jump = CrossPlatformInputManager.GetButtonDown("Jump");
}
}
// Fixed update is called in sync with physics
private void FixedUpdate()
{
// read inputs
float h = CrossPlatformInputManager.GetAxis("Horizontal");
float v = CrossPlatformInputManager.GetAxis("Vertical");
bool crouch = Input.GetKey(KeyCode.C);
// calculate move direction to pass to character
if (m_Cam != null)
{
// calculate camera relative direction to move:
m_CamForward = Vector3.Scale(m_Cam.forward, new Vector3(1, 0, 1)).normalized;
m_Move = v*m_CamForward + h*m_Cam.right;
}
else
{
// we use world-relative directions in the case of no main camera
m_Move = v*Vector3.forward + h*Vector3.right;
}
#if !MOBILE_INPUT
// walk speed multiplier
if (Input.GetKey(KeyCode.LeftShift)) m_Move *= 0.5f;
#endif
// pass all parameters to the character control script
m_Character.Move(m_Move, crouch, m_Jump);
m_Jump = false;
}
void OnCollisionEnter(Collision other)
{
if (other.gameObject.CompareTag("Present"))
{
Destroy(other.gameObject);
count = count - 1;
SetCountText();
//FindObjectOfType<AudioManager>().Play("CatchingPresent");
AudioManager.instance.Play("CatchingPresent");
}
}
void SetCountText()
{
countText.text = "Missing: " + count.ToString();
if (count == 0)
{
winText.text = "You saved Christmas!";
}
}
}
}
Edit 2: Hierarchy in Unity:

Reformulated the approach that I was following and solved the problem by simply adding an Audio Source to the ThirdPersonController (with the AudioClip that I wanted to call) and added GetComponent<AudioSource>().Play(); to the if statement as it follows:
void OnCollisionEnter(Collision other)
{
if (other.gameObject.CompareTag("Present"))
{
Destroy(other.gameObject);
count = count - 1;
SetCountText();
GetComponent<AudioSource>().Play();
}
}

Importing your scripts myself works without any issues when using FindObjectOfType<AudioManager>().Play("CatchingPresent");. Try reimporting your scripts from the editor (right click in the project folder > reimport all. this might take a while depending on the size of your project)
to use AudioManager.instance.Play("CatchingPresent"); you would first need to create a static variable that holds instance like this (this only works as a singleton, and will break if multiple AudioManager's are in the scene):
public class AudioManager : MonoBehaviour
{
//Create a static AudioManager that will hold the reference to this instance of AudioManager
public static AudioManager Instance;
public Sound[] sounds;
//Assign Instance to the instance of this AudioManager in the constructor
AudioManager()
{
Instance = this;
}
// Rest of the AudioManager code
}
Doing it like this, and using the rest of your code also works for me.

Unity Engine - Instantiate a prefab by collision

I have a GameObject called Player.
Attached to Player there is a script component called Player ( same )
Inside the Player's script, I have a field called _weaponPrefab ( GameObject type )
In the Inspector, I can easily drag & drop any prefabs from my Prefab folder, inside the _weaponPrefab variable.
All good so far. What I want to archive is: to be able to add my Prefabs based on a Collision2D. So if my Player collides with a Prefab, let's say a Sword, the prefab of that sword will be automatically attached and insert into the _weaponPrefab field inside the Player script.
Below my Player script:
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Player : MonoBehaviour
{
[SerializeField] private float _speed = 5.0f;
[SerializeField] private float _fireRate = 0.2f;
private bool _canFire = true;
[SerializeField] private GameObject _weaponPrefab; <- to populate runtime
// Use this for initialization
void Start ()
{
transform.position = Vector3.zero;
}
// Update is called once per frame
void Update ()
{
if (Input.GetKeyDown(KeyCode.Space) && _canFire)
StartCoroutine(Shoot());
}
void OnTriggerEnter2D(Collider2D other)
{
//here i don't know how to continue.
}
public IEnumerator Shoot()
{
_canFire = false;
Instantiate(_weaponPrefab, transform.position + new Vector3(0, 1, 0), Quaternion.identity);
yield return new WaitForSeconds(_fireRate);
_canFire = true;
}
}
Edit: i just wrote a comment of where i don't know how to proceed.

There are many ways to accomplish what you desire.
My suggestion may be out of your comfort zone at first, but it will provide you with most flexibility and eventually easy of programming/ designing/ maintaining your game (in my opinion).
First make a scriptable object (what is a scriptable object and how do i use it?)
using UnityEngine;
using System.Collections;
using UnityEditor;
public class Item
{
[CreateAssetMenu(menuName = "new Item")]
public static void CreateMyAsset()
{
public GameObject prefab;
// you can add other variables here aswell, like cost, durability etc.
}
}
Create a new item (in Unity, Assets/new Item)
Then create a monobehaviour script which can hold the item. In your case let's name it "Pickup".
public class Pickup : MonoBehaviour
{
public Item item;
}
Finally in your player script, change your on TriggerEnter to:
void OnTriggerEnter2D(Collider2D other)
{
if(other.GetComponentInChildren<Pickup>())
{
var item = other.GetComponentInChildren<Pickup>().item;
_weaponPrefab = item.prefab;
}
}

When you instantiate a GameObject you need to pass basically 3 parameters (However not all of them are mandatory, check):
The prefab
The position
The rotation
Let's assume you have a placeholder in the hand or in the back of your character, to keep there the weapon once collected. This placeholder can be an empty gameobject (no prefab attached, but will have a transform.position component)
Now let's assume you have a list of weapons in the scene with their prefab and with a different tag each. Then you can do something like this:
GameObject weapon;
GameObject placeholder;
public Transform sword;
public Transform bow;
...
void OnTriggerEnter2D(Collider2D other)
{
//You can use a switch/case instead
if(other.gameObject.tag == "sword"){
Instantiate(sword, placeholder.transform.position, Quaternion.identity);
}else if(other.gameObject.tag == "bow"){
Instantiate(bow, placeholder.transform.position, Quaternion.identity);
}...
}

What I'll do is load the prefabs first in a Dictionary<string, GameObject> from the resources folder.
First I populate the dictionary with all the weapon prefabs in the Start method with the tag of the object as a key. Then in the OnTriggerEnter2D I check if the tag is in the dictionary then I instantiate it from there.
Take a look at the code :
private Dictionary<string, GameObject> prefabs;
// Use this for initialization
void Start () {
var sword = (GameObject) Resources.Load("Weapons/sword", typeof(GameObject));
prefabs.Add("sword", sword);
// Add other prefabs
};
void OnTriggerEnter2D(Collider2D other)
{
if (prefabs.ContainsKey(other.tag))
Instantiate(prefabs[other.tag]);
}
NOTE : your prefabs needs to be in the folder Assets/Resources/Weapons because I used Resources.Load("Weapons/sword", typeof(GameObject));

Control animation and execute script when animation ends

My project is a military fps and i'm having some problems with animations.
I have 3 different weapons, 1 animator controller for each one and every weapon has a "enter" and "leave" animation. Like CS, COD, etc...
I need to know when my "leave" animation ends to disable the gameobject, enable the other one and play the "enter" animation.
I tryed to do this: http://answers.unity3d.com/questions/362629/how-can-i-check-if-an-animation-is-being-played-or.html but without sucess.
I'll leave here a print of the animator controller, the hierarchy and the script, if u need more details, just need to say.
Animator controller of the weapon number 1
All transitions to "Sair" (leave animation) have a trigger (AK47_sair) and the transition to "Extit" state have a trigger ("AK47_SairControlador")
On my code, when i press 2 (change to weapon number 2) i want to do the transition.
This is the hierarchy, my script is attached to "Jogador".
With my actual code, it disable tha AK47 gameobject when the leave animation still playing.
using UnityEngine;
using System.Collections;
public class FirstPerson : MonoBehaviour {
public float speed;
public float normalSpeed = 5.0f;
public float slowSpeed = 2.5f;
public float crchSpeed = 2.5f;
private Transform tr;
private float dist; // distance to ground
public float mouseSensitivity = 5.0f;
public float verticalRotation = 0.0f;
public float updownRange = 60.0f;
private float verticalSpeed = 0.0f;
public float jumpSpeed = 5.0f;
CharacterController player;
private GameObject AK47;
private GameObject Faca;
public float shootingRate = 0.15f;
public float shootCooldown;
private bool agachado = false;
public float camOriginalPositionY;
public float camCrouchPositionY;
private Animator controladorAnimacaoAK;
private Animator controladorAnimacaoFaca;
public CapsuleCollider playerCollider;
public Camera CameraPrincipal;
public int ArmaSelecionada;
public int UltimaArma;
void Start () {
player = GetComponent<CharacterController>();
shootCooldown = 0;
controladorAnimacaoAK = player.GetComponentInChildren<Animator>();
playerCollider = gameObject.GetComponent<CapsuleCollider> ();
CameraPrincipal = Camera.main;
ArmaSelecionada = 1;
AK47 = CameraPrincipal.transform.FindChild ("ak47_final_animado").gameObject;
}
void Update () {
if (Input.GetKeyDown (KeyCode.Alpha2) || Input.GetKeyDown(KeyCode.Keypad2)) {
UltimaArma = ArmaSelecionada;
ArmaSelecionada = 2;
if(UltimaArma == 1) {
controladorAnimacaoAK.SetTrigger("AK47_Sair");
controladorAnimacaoAK.SetTrigger("AK47_SairControlador");
AK47.SetActive (false);
}
}
if (Input.GetKeyDown (KeyCode.Alpha1)) {
UltimaArma = ArmaSelecionada;
ArmaSelecionada = 1;
// controladorAnimacaoAK.SetTrigger ("AK47_Entrar");
}
if (ArmaSelecionada == 1) {
// diz ao controlador da anim se o player esta a movimentar-se ou nao
controladorAnimacaoAK.SetFloat ("AK47_Deslocacao", player.velocity.magnitude);
//Debug.Log (player.velocity.magnitude);
// dispatar tiros
PlayerShoot PlayerShootScript = player.GetComponent<PlayerShoot> ();
if (shootCooldown > 0) {
shootCooldown -= Time.deltaTime;
}
if (Input.GetButton ("Fire1")) {
if (shootCooldown <= 0) {
shootCooldown = shootingRate;
PlayerShootScript.FireShoot ();
// animaçao
controladorAnimacaoAK.SetBool ("AK47_Disparar", true);
}
} else {
// animaçao
controladorAnimacaoAK.SetBool ("AK47_Disparar", false);
}
if (Input.GetKeyDown (KeyCode.R)) {
controladorAnimacaoAK.SetTrigger ("AK47_rec");
}
}
}
}

In Unity 5 you've got this new thing which is Animation State Machine Behavior : State Machine Behaviours
You can use it to specify behavior when the Animation Controller enters or leave specific states.
For exemple here I've got my door which have an Open and Close state, and let's say that I want to play a sound when the door is opening.
Here I clicked Opening, then Add Behaviour and set a random name for the test (Behavior Test in my case)
Then I just need to implement the function void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex) to play a sound at the first frame the animation is running.
[SerializeField]
AudioClip open_sound;
override public void OnStateEnter(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
{
animator.GetComponent<AudioSource>().clip = open_sound;
animator.GetComponent<AudioSource>().Play();
}
In your case, you would want to implement a behavior in the state Disparar which implements the function OnStateExit([...]) and handle the weapon change.
To go a bit further I don't think you should handle the weapon change directly in the animation state, but maybe your script could send an event catched by a Game Controller that will actually handle the change of weapon.