I'm pretty new to C# and I'm currently developing a small 2D game. I have a script for the collisions so that I get a Debug.Log() whenever my character touches something. This is the script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Collidable : MonoBehaviour
{
public ContactFilter2D filter;
private BoxCollider2D boxCollider;
private Collider2D[] hits = new Collider2D[10];
protected virtual void Start()
{
boxCollider = GetComponent<BoxCollider2D>();
}
protected virtual void Update()
{
//Collision Work
boxCollider.OverlapCollider(filter, hits);
for(int i=0; i<hits.Length; i++)
{
if(hits[i] == null)
continue;
OnCollide(hits[i]);
hits[i] = null;
}
}
protected virtual void OnCollide(Collider2D coll)
{
Debug.Log(coll.name);
}
}
I would like to get only 1 console log whenever my character is, for example, picking up, therefore, touching a chest and get a message what he picked up, but for as long as the character is touching the chest, the Logs won't stop flying.
How can I fix that?
Thanks in advance
You have to add a flag (a boolean) to call the method only once
At the top of the script, initialize a boolean variable hasCollided which is set to false on default.
private bool hasCollided = false;
Call the OnCollide() method only when the collision has not occurred yet and when the collision has occurred, set hasCollided to true.
protected virtual void OnCollide(Collider2D coll)
{
if(!hasCollided)
{
Debug.Log(coll.name);
hasCollided = true;
}
}
This calls the OnCollide() method only once.
The official documentation for Collider2D.OverlapCollider states that
Get a list of all colliders that overlap this collider.
and you are checking that on Update() meaning your collision code get executed everytime there are any collider overlapping your BoxCollider2D
You should look into Collider.OnCollisionEnter which gets called when this collider/rigidbody has begun touching another rigidbody/collider.
However collision events are only sent if one of the colliders also has a non-kinematic rigidbody attached.
Related
I am creating a game in unity where the player can drag one object (a card) over another (an enemy). If they drag the card over the enemy I want to run some code, and if not I want to return the card to its initial position. I placed a collider on both objects but it isnt working the way it should. I am assuming this is because the object is getting moved back to its initial location before the physics engine sees the collision, but I don't know how to fix this. I am deactivating the collider on the card while moving it to avoid having it trigger collisions until the player has placed it using the onmousedown and onmouseup events. Any tips on how to fix this behavior? can I force the physics engine to check collisions with the onmouseup event?
I know the collisions are working because when I turn off the return to initial position behavior the game functions as expected.
How about useing the collider as trigger and do not use rigidbodys or anything.
Then if there is a trigger enter event set bool as true. If there trigger exit reset the bool to false.
Now if you "Release" the card check if bool is true or false.
true: Set the cards position to the player or what you want
false: Reset the cards position to the start
Now beeing a little mroe fancy you can set a lighted border around the card when bool is active (just check in update)
Example:
public class Card : MonoBehaviour {
private bool isHolding;
private bool isHovering;
public Vector3 startPos;
public void Start() {
startPos = transform.position;
}
public void Update() {
// Code where you check if the card is Clicked and Moved by the player
// If so set isHolding = true
// dont enter the check if holding blablabla when animation stuff is happening
if (doAnimationStuff) {
// do animation
// Destroy Object
return;
}
// Code to check if isHolding == false
if (!isHolding) {
if (!isHovering) {
transform.position = startPos;
} else {
doAnimationStuff = true;
}
}
}
private void OnTriggerEnter(Collider other) {
// Check if other is a player
// if so set isHovering = true
}
private void OnTriggerExit(Collider other) {
// Check if other is a player
// if so set isHovering = false
}
}
I am in the middle of creating a simple 3d platformer in unity and i'm trying to make it so if you are in a certain radius and you hit the "f" key the enemy will disappear. the way i'm checking to make sure the enemy is close enough to be attacked is to have trigger sphere and when its triggered and you press "f" the enemy will be removed. i'm currently trying to see what collided with the trigger but i cant figure it out. here is my current code
using UnityEngine;
public class PlayerCombat : MonoBehaviour
{
public GameObject Enemy1;
public GameObject Enemy2;
public GameObject Enemy3;
public GameObject Enemy4;
// Update is called once per frame
void OnTriggerEnter (Trigger triggerInfo)
{
if (triggerInfo.collider.tag == "Enemy" & Input.GetKey("f"))
{
if (triggerInfo.collider.name == Enemy)
{
Enemy1.SetActive(false);
}
}
}
}
The signature is and has always been OnTriggerEnter(Collider) otherwise that message method will not be recognized by Unity and not get called at all!
And then you already have the according Collider ... what else do you need?
public class PlayerCombat : MonoBehaviour
{
// There is no need to know the enemy references beforehand at all
// you will get all required references from the Collider parameter of OnTriggerEnter itself
// I personally would however expose these two settings to the Inspector to be more flexible
// this way you can adjust these two settings within Unity without having to touch your code
public string listenToTag = "Enemy";
public KeyCode listenToKey = KeyCode.F;
// The signature has to be this otherwise the message method is never invoked at all
private void OnTriggerEnter (Collider other)
{
// Rather use "CompareTag" instead of `==` since the latter will silently fail
// for typos and nonexistent tags while "CompareTag" shows an error which is good for your debugging
// And in general you want to use the logical "&&" instead of the bitwise operator "&" for bools
if (other.CompareTag(listenToTag) && Input.GetKey(listenToKey))
{
// simply set the object you collide with inactive
other.gameObject.SetActive(false);
}
}
}
Finally just make sure that all your enemy instances actually have the tag Enemy
First, I'm pretty sure OnTriggerEnter takes a Collider as its parameter, no? https://docs.unity3d.com/ScriptReference/Collider.OnTriggerEnter.html
You can get the name of the collided object like so
//Upon collision with another GameObject,
private void OnTriggerEnter(Collider other)
{
Debug.Log($"collided with {other.gameObject.name}");
//you can check for specific components too
MyComponent myComponent = other.GetComponent<MyComponent>();
if (myComponent != null) {
// do something if it has that component on it!
}
}
I am trying to create a script for my enemy turret, but it is not going well. I have a couple animations of the turret being activated and deactivated. What I need is that based on the distance from the player, it plays either animation. So once it moves inside the detection radius it plays the activation animation and once it is outside it plays the deactivation animation. Most of the other ways I try require me to create an Animation Controller, which I have little experience in using. I want a simple way to play one animation once it is inside and play a different one when it is outside. I think there was a way to store the animation clip in the script, and then play it. I have attached my current script, so you know what I mean.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class EnemyTurret : MonoBehaviour
{
public GameObject Player;
public float DistanceToPlayer;
public float DetectionRadius = 75;
// Start is called before the first frame update
void Start()
{
Player = GameObject.FindGameObjectWithTag("PlayerTank");
}
// Update is called once per frame
void Update()
{
DistanceToPlayer = Vector3.Distance(transform.position, Player.transform.position);
if (DistanceToPlayer<=DetectionRadius)
{
Debug.Log("Within Radius");
}
if (DistanceToPlayer >= DetectionRadius)
{
Debug.Log("Outside Radius");
}
}
}
Calculating and checking the distance of the player for every update() is not ideal. It will work, but it will do more work than it needs to when the player isn't even near it. Its not efficient.
What you may want to do if your player is a Rigidbody, is add a SphereCollider to the turret, set isTrigger=true, set the radius to be your detection radius, and handle the OnTriggerEnter() and OnTriggerExit() events to play or stop animations.
You can also add two public Animiation objects to the script, drag and drop your animations in the editor, then you can use animation.Play() and .Stop() etc. to control the animations.
Something similar to this. Not tested fully, but you can get the idea.
public float detectionRadius = 75;
public Animation activateAnimation;
public Animation deactivateAnimation;
void Start()
{
SphereCollider detectionSphere = gameObject.AddComponent<SphereCollider>();
detectionSphere.isTrigger = true;
detectionSphere.radius = detectionRadius;
detectionSphere.center = Vector3.zero;
}
private void OnTriggerEnter(Collider other)
{
if (other.gameObject.tag == "PlayerTank")
{
activateAnimation.Play();
}
}
private void OnTriggerExit(Collider other)
{
if (other.gameObject.tag == "PlayerTank")
{
deactivateAnimation.Play();
}
}
Your animations must not loop otherwise you will have to add more logic to check if animation.isPlaying and do your own animation.Stop() etc.
I'm making a game in Unity VR in which I punch numbers and get points.
The gloves are responsible for detecting collisions between the numbers that they hit. On my gloves I have a PunchScript component and the numbers each have a rigidBody and collider.
The problem is that no collisions seem to ever occur. I placed a Debug.LogError inside of the collision detection code to assert this.
I tried switching on/off kinematics on all objects and used different collision systems to no avail.
Here's my PunchScript component:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PunchScript : MonoBehaviour
{
public SteamVR_TrackedObject hand;
private Rigidbody rBody;
private bool visible = true;
// Start is called before the first frame update
void Start()
{
rBody = GetComponent<Rigidbody>();
}
// Update is called once per frame
void Update()
{
rBody.MovePosition(hand.transform.position);
rBody.MoveRotation(hand.transform.rotation);
// print(rBody.velocity.magnitude* 1000);
}
void OnCollisonEnter(Collision other)
{
Rigidbody otherR = other.gameObject.GetComponentInChildren<Rigidbody>();
if (other.gameObject.name == "frpnchbg") {
Debug.LogError("Hit!");
}
if (other == null)
return;
Vector3 avgPoint = Vector3.zero;
foreach (ContactPoint p in other.contacts) {
avgPoint += p.point;
}
avgPoint /= other.contacts.Length;
Vector3 dir = (avgPoint - transform.position).normalized;
otherR.AddForceAtPosition(dir *50f* rBody.velocity.magnitude, avgPoint);
}
}
Here's how the glove object looks in the Unity inspector.
It is very important to write the name of Unity callback methods correctly, otherwise Unity will not be able to detect them on the object (and as a result, can never execute them).
In your case, you have misspelled the OnCollisionEnter callback.
Instead of OnCollisonEnter it should be OnCollisionEnter.
I am trying to make my player hit an object, destroying the object and triggering an animation, but everything I try causes an error. I am relatively new at c# so the answer may be obvious but I need help. How can I set it up so that the collision will cause the object to disappear and the player to play an animation? Here is the script I am currently trying.
using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.SceneManagement;
public class succ : MonoBehaviour
{
public float speed = .15f;
public static float jumpSpeed = 170f;
void Start()
{
GetComponent<ConstantForce2D>().enabled = false;
GameObject.Find("goal");
}
public bool animation_bool;
private object coll;
private object other;
void Update()
{
OnCollisionStay2D(Collision2D coll);
{
if (coll.gameObject.tag == "succ") ;
{
animation_bool = true;
GetComponent<Animator>().SetBool("succ", animation_bool);
GetComponent<ConstantForce2D>().enabled = true;
Destroy(other.object);
}
}
}
private void Destroy(object gameObject)
{
throw new NotImplementedException();
}
private void OnCollisionStay2D(Collision2D collision2D, object coll)
{
throw new NotImplementedException();
}
}
There are a few things I can see that are wrong, but I'll start by answering your question.
I suggest you change your MonoBehaviour method OnCollisionStay2D to OnCollisionEnter2D. OnCollisionStay2D is "sent each frame where a collider on another object is touching this object's collider". OnCollisionEnter2D is "sent when an incoming collider makes contact with this object's collider".
I believe you are looking for the latter since you only want to trigger this once during the collision. You are also destroying the other object, making it impossible to call OnCollisionStay2D anymore even if you wanted to do so.
You should also remove your Update method. I honestly do not understand what you are trying to achieve there now. All of the OnCollision methods get called automatically; you do not have to call them yourself.
Then you can use the Awake and OnCollisionEnter2D methods as follows
public class Succ : MonoBehaviour
{
private Animator animator;
private void Awake()
{
// You can already get a reference to the Animator on Awake
// This way you do not have to do it on every collision
animator = GetComponent<Animator>();
}
// Use OnCollisionEnter2D instead since the code
// needs to be excecuted only once during the collision
private void OnCollisionEnter2D(Collision2D collision)
{
if (collision.gameObject.CompareTag("succ")
{
// Assuming that you only want to trigger an animation once
// to reflect attacking or colliding, you could use SetTrigger
// instead. Otherwise you need to use SetBool again to set it
// back to false. You should then change the Animator parameter
// accordingly, from a bool to a trigger.
animator.SetTrigger("succ");
Destroy(collision.gameObject);
}
}
}
Apart from this, I have a few things I would like to comment on:
I am not sure what you are trying to achieve by setting your ConstantForce2D component to false on Start and then setting it to true on collision.
You seem to be using GameObject.Find on Start. GameObject.Find is something that should be very rarely used. It can be extremely expensive, especially if your Scene has a lot of GameObjects in it; this is because it simply goes through the Hiearchy, comparing the parameter string to names of GameObjects until it either finds a match or runs out of GameObjects.
Moreover, you are using GameObject.Find on Start to look for a GameObject, but then you do not store that anywhere, making the whole finding process completely pointless.
Overall, I recommend you to take a look at all of the different learning resources offered by Unity themselves. Your question is about fairly basic functionality that is certainly covered during all of the different tutorials.