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collision not working properly in unity when moving

so I have rigid body and when it collides with another body with low speeds it is working just fine but when it collides with hight speed it goes through the object I've Been have this problem for day and I can't fix it
here's my code
this is my player movement file
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CharcterController : MonoBehaviour
{
// Start is called before the first frame update
public Vector3 PlayerMovementVar;
public Rigidbody Rigidbody_comp;
// Start is called before the first frame update
void Start()
{
Rigidbody_comp = GetComponent<Rigidbody>();
}
// Update is called once per frame
void Update()
{
PlayerMovement();
}
void PlayerMovement()
{
float horizontalAxis = Input.GetAxis("Horizontal")/30;
float verticalAxis = Input.GetAxis("Vertical")/30;
PlayerMovementVar = new Vector3(horizontalAxis,0f,verticalAxis);
transform.Translate(PlayerMovementVar,Space.Self);
}
}

I shouldn't be the one answering this since I have very little knowledge of unity but I'm pretty sure it might be because you are using transform.Translate which I think it avoids collisions try using a character controller instead :)

If you want to use properly Unity physics system you must use Forces instead of Translate direcly your gameobject.
Try this:
Rigidbody_comp.AddForce(PlayerMovementVar);
instead of
transform.Translate(PlayerMovementVar,Space.Self);

RigidBody movement and Transform movement are different from each other, each causes a different type of movement. when moving with a rigidbody, in order to use its physics ability, you should move it instead of the usual transform.Translate.
Rigidbody_comp.AddForce(PlayerMovementVar);

C# (Galaga Style Project) - Limit Projectile Prefab Clones based on Hierarchy

I am trying to practice creating a clone of Galaga following the same ruleset as the original. I am currently stuck trying to attempt a limit on the amount of cloned prefabs that can be in the scene at any one time, in the same way that Galaga's projectiles are limited to 2 on screen at any time. I want to make it so the player can shoot up to two projectiles, which destroy after 2 seconds or when they collide (this part is functioning), followed by not being able to shoot if two projectile clones are active and not yet destroyed in the hierarchy (Not working as I can instantiate projectiles over the limit of 2).
I have combed through Google for about 3 hours with no solutions that have worked for me, at least in the ways that I had attempted to implement them.
Thank y'all so much for the help!
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class playerController : MonoBehaviour
{
public float moveSpeed = 1.0f;
public playerProjectile projectile;
public Transform launchOffset;
public int maxBullets = 0;
private GameObject cloneProjectile;
public Rigidbody2D player;
// Start is called before the first frame update
void Start()
{
player = this.GetComponent<Rigidbody2D>();
}
// Update is called once per frame
void Update()
{
MovePlayer();
PlayerShoot();
}
public void MovePlayer()
{
player.velocity = new Vector2(Input.GetAxis("Horizontal"), Input.GetAxis("Vertical")) * moveSpeed;
}
public void PlayerShoot()
{
if (Input.GetKeyDown(KeyCode.Z))
{
var cloneProjectile = Instantiate(projectile, launchOffset.position, launchOffset.rotation);
maxBullets++;
if (maxBullets >= 3)
{
Destroy(cloneProjectile, 0.1f);
maxBullets --;
return;
}
}
}
}

You could change the logic up a bit. An instance of the playerController class is active as long as the game is active, so it will know and retain the value of 'maxBullets' until you die or exit the program.
So instead, every time you click "z", the first thing you should do is run the check. If the current amount of live projectiles equals the maximum, have the logic 'return' and exit out of the method.

Centre of mass not recalculated after scaling

I am spawning a prefab object at runtime (actually, in the Start() method of another object), and I need to apply a scaling to the object. I made a little component to handle this:
public class Spawner : MonoBehaviour {
public Transform SpawnPrefab;
public Vector3 Scale;
void Start () {
var spawn = Instantiate(SpawnPrefab, Vector3.zero, Quaternion.identity);
spawn.localScale = Vector3.Scale(spawn.localScale, Scale);
// spawn.GetComponent<Rigidbody>().ResetCenterOfMass(); // Has no effect
}
}
The pivot point of the prefab I am spawning does not coincide with the centre of mass of the object. Therefore, the rescaling means that the centre of mass location relative to the pivot will change. However, it's not being updated automatically, so my spawned object has unexpected physics.
I tried adding a call to GetComponent<Rigidbody>().ResetCenterOfMass() immediately after the call to Scale() (the commented-out line above), but this has no effect.
However, if I put the call to ResetCenterOfMass() in the Start() method of a separate little component added to the spawned object, e.g.
public class COMReset : MonoBehaviour {
void Start() {
GetComponent<Rigidbody>().ResetCenterOfMass();
}
}
this does cause the centre of mass to be recalculated correctly. However, the spawned object appears to have already been through at least one physics update with the wrong COM by this time, and so has already acquired some unexpected momentum.
Why isn't the COM being automatically recalculated, without me having to call ResetCenterOfMass() explicitly? And if I must trigger it manually, can I do that immediately after the calls to Instantiate() and Scale(), rather than deferring like this?

With thanks to #DMGregory on GameDev for the suggestion, a call to Physics.SyncTransforms before invoking Rigidbody.ResetCenterOfMass fixes the problem:
public class Spawner : MonoBehaviour {
public Transform SpawnPrefab;
public Vector3 Scale;
void Start () {
var spawn = Instantiate(SpawnPrefab, Vector3.zero, Quaternion.identity);
spawn.localScale = Vector3.Scale(spawn.localScale, Scale);
Physics.SyncTransforms();
spawn.GetComponent<Rigidbody>().ResetCenterOfMass();
}
}
Evidently this direct modification of the transform scale isn't being automatically passed through to the physics engine, but Physics.SyncTransforms lets us manually flush those changes down to PhysX, so that the ResetCenterOfMass computation is then based on the correctly scaled transform.

A collision triggers an animation

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.

Score Count not working on a prefab

This is semi complicated of a question but I'll do my best to explain it:
I am making this mobile game in which you have to shoot four cubes. I'm trying to make it so when the cubes are shot by a bullet, they're destroyed and a UI text says 1/4, to 4/4 whenever a cube is shot. But it's being really weird and only counts to 1/4 even when all four cubes are shot and destroyed. I put these two scripts on the bullets (I made two separate scripts to see if that would do anything, it didn't)
And to give a better idea of what I'm talking about, here's a screenshot of the game itself.
I've been using Unity for about 6 days, so I apologize for anything I say that's noob-ish.
EDIT
So I combined the two scripts onto an empty gameobject and here's the new script:
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class GameManagerScript : MonoBehaviour {
public GameObject cubes;
public Text countText;
public int cubeCount;
public Transform target;
// Use this for initialization
void Start () {
}
void OnTriggerEnter(Collider other)
{
cubes = other.gameObject;
}
// Update is called once per frame
void Update () {
cubes.transform.position = Vector3.MoveTowards(transform.position, target.position, 1f * Time.deltaTime);
if (cubes.gameObject.tag == "BULLET")
{
cubeCount = cubeCount + 1;
countText.text = cubeCount + "/4";
cubes.SetActive(false);
}
}
}
ANOTHER EDIT
I tried everything, so is there a way to detect when all the children in a parent on the Hierarchy are destroyed? Instead of counting up? This can give a better idea:
So I want to be able to detect when Cube, Cube1, Cube2, and Cube3 have all been destroyed.

The answer is pretty simple: Since every individual bullet has that script, each bullet has its own score.
For something like a score you want a single spot to store it, e.g. a script on an empty gameobject that serves as game controller. Just access that in the collision and increase the score (maybe have a look on singletons here).
You can combine those two scripts and actually it might be better to not have this on the bullet, but on the target because there are probably less of them which will save you some performance. (And it does more sense from a logical point of view.)
Edit:
I assume you create the bullets using Instantiate with a prefab. A prefab (= blueprint) is not actually in the game (only objects that are in the scene/hierarchy are in the game). Every use of Instantiate will create a new instance of that prefab with it's own version of components. A singleton is a thing that can only exist once, but also and that is why I mention it here, you can access it without something like Find. It is some sort of static. And an empty gameobject is just an object without visuals. You can easily create one in unity (rightclick > create empty). They are typically used as container and scriptholders.
Edit:
What you want is:
An empty gameobject with a script which holds the score.
A script that detects the collision using OnTriggerEnter and this script will either be on the bullets or on the targets.
Now, this is just a very quick example and can be optimized, but I hope this will give you an idea.
The script for the score, to be placed on an empty gameobject:
public class ScoreManager : MonoBehaviour
{
public Text scoreText; // the text object that displays the score, populate e.g. via inspector
private int score;
public void IncrementScore()
{
score++;
scoreText.text = score.ToString();
}
}
The collision script as bullet version:
public class Bullet : MonoBehaviour
{
private ScoreManager scoreManager;
private void Start()
{
scoreManager = GameObject.FindWithTag("GameManager").GetComponent<ScoreManager>(); // give the score manager empty gameobject that tag
}
private void OnTriggerEnter(Collider other)
{
if(other.CompareTag("Target") == true)
{
// update score
scoreManager.IncrementScore();
// handle target, in this example it's just destroyed
Destroy(other.gameObject);
}
}
}