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2d Platformer game stone changing size

I am trying to make a platformer game. In the platformer game has a moving platform that makes everything it touches its transform's child while it touches it. Interestingly, whenever a stone(A movable object with a rigidbody and a polygon collider) touches the moving platform, the stone's scale goes haywire. Even though the scale reads the same on the transform component, it appears to be larger or smaller than it really is when touching it. When it stops touching the platform, the stone appears normal. Can anyone help me. Thank you.
This is the moving platform script that moves the platform around.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class MoveTwoTransforms : MonoBehaviour
{
public Transform pointA;
public Transform pointB;
public bool HasReachedA;
public bool HasReacedB;
// Start is called before the first frame update
void Start()
{
transform.position = pointA.position;
HasReacedB = true;
HasReachedA = false;
StartCoroutine(GlideAround());
}
// Update is called once per frame
void Update()
{
}
public IEnumerator GlideAround()
{
while (true)
{
while (HasReachedA == false)
{
yield return new WaitForEndOfFrame();
transform.position = Vector2.Lerp(transform.position, pointA.position, 0.01f);
if ((Mathf.Abs(Vector2.Distance(pointA.position, transform.position)) < 0.01f))
{
HasReacedB = false;
HasReachedA = true;
}
}
while (HasReacedB == false)
{
yield return new WaitForEndOfFrame();
transform.position = Vector2.Lerp(transform.position, pointB.position, 0.01f);
if ((Mathf.Abs(Vector2.Distance(pointB.position, transform.position)) < 0.01f))
{
HasReacedB = true;
HasReachedA = false;
}
}
}
}
private void OnCollisionEnter2D(Collision2D collision)
{
if((collision.gameObject.tag == "Stone"|| collision.gameObject.tag == "Player") && (collision.transform.position.y - collision.transform.lossyScale.y / 2 >= transform.position.y))
{
collision.transform.parent = transform;
}
}
private void OnCollisionExit2D(Collision2D collision)
{
collision.transform.parent = null;
}
}
This is the stone script
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class RememberPositions : MonoBehaviour
{
public Vector3 StartingPosition;
public Vector3 StartingRotation;
public Vector3 StartingScale;
float StartRotation;
// Start is called before the first frame update
void Start()
{
StartingPosition = new Vector3(transform.position.x, transform.position.y, 0);
StartingRotation = new Vector3(0, 0, transform.position.z);
StartingScale = new Vector3(transform.localScale.x, transform.localScale.y, transform.localScale.z);
}
// Update is called once per frame
void Update()
{
transform.localScale = StartingScale;
}
}
There are no errors whatsoever and the rigidbody seems to be changing to the shape of the stone. Can anyone please specify the correct code I should use? Thank you.

If your moving platform is scaled, your stone will get scaled too. There are workarounds shown here to avoid this issue. One of them is adding a child GameObject to the platform, and moving the collision handling from the platform to that child.

How do i set the velocity of a sprite to the opposite direction of the mouse pointer at a certain speed?

/*I am making a 2d game in Unity that works similarly to billiards, but with other aspects. When the player holds down button 0, a line drags away from the ball to show the direction and speed the ball will be hit off in. I don't know how to set that velocity or how to add a force like that.
I've tried setting the velocity directly, then adding fake frictions, but that didn't work too well. I also tried adding a force to the ball, and also making an empty game object that follows the pointer with a point effecter to repel the ball. But I cant seem to get anything to work.
--Also I apologize for the messy code, i'm still kinda new to this
*/
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class LineDrawer : MonoBehaviour
{
public Transform tr; //this is the transform and rigid body 2d of the
ball
public Rigidbody2D rb;
public LineRenderer line; // the line rendered is on the ball
public float hitForce = 10;
// Start is called before the first frame update
void Start()
{
line = GetComponent<LineRenderer>();
line.SetColors(Color.black, Color.white);
}
// Update is called once per frame
void FixedUpdate()
{
line.SetPosition(0, tr.position - new Vector3(0, 0, 0));
if (Input.GetMouseButton(0)&&PlayerPrefs.GetInt("Moving")==0)
{
line.SetWidth(.25f, .25f);
line.SetPosition(1, Camera.main.ScreenToWorldPoint(Input.mousePosition));
float len = Vector2.Distance(line.GetPosition(0), line.GetPosition(1)); //this is for determining the power of the hit
}
else
{
line.SetWidth(0, 0); //make the line invisible
}
if (Input.GetMouseButtonUp(0) && (PlayerPrefs.GetInt("Moving")==0))
{
Vector2.Distance(Input.mousePosition, tr.position)*100;
Debug.Log("Up");
rb.velocity = //this is what i cant work out
PlayerPrefs.SetInt("Moving", 1);
}
}
}
//5 lines from the bottom is where i'm setting the velocity.

Just rewrite your script to the following:
using UnityEngine;
public class Ball : MonoBehaviour
{
private LineRenderer line;
private Rigidbody2D rb;
void Start()
{
line = GetComponent<LineRenderer>();
rb = GetComponent<Rigidbody2D>();
}
void Update()
{
line.SetPosition(0, transform.position);
if (Input.GetMouseButton(0))
{
line.startWidth = .05f;
line.endWidth = .05f;
line.SetPosition(1, Camera.main.ScreenToWorldPoint(Input.mousePosition));
}
else
{
line.startWidth = 0;
line.endWidth = 0;
}
if (Input.GetMouseButtonUp(0))
{
Vector2 direction = Camera.main.ScreenToWorldPoint(Input.mousePosition) - transform.position;
direction.Normalize();
rb.AddForce(direction * 3f, ForceMode2D.Impulse);
}
}
}

How to add force to an object after a collision in unity2d, to simulate hitting a baseball with a bat

I am working on a 2D game project. I would like the user to be able to hit the ball when he presses on the "space" key. I assigned;
Circle collider 2D & Rigidbody 2D to the ball
Rigidbody 2D & Box Collider 2D to the hero
Edge Collider 2D to the baseball bat.
Here is my script which I have called "KickTheBall.cs":
using UnityEngine;
using System.Collections;
public class KickTheBall : MonoBehaviour {
public float bounceFactor = 0.9f; // Determines how the ball will be bouncing after landing. The value is [0..1]
public float forceFactor = 10f;
public float tMax = 5f; // Pressing time upper limit
private float kickStart; // Keeps time, when you press button
private float kickForce; // Keeps time interval between button press and release
private Vector2 prevVelocity; // Keeps rigidbody velocity, calculated in FixedUpdate()
[SerializeField]
private EdgeCollider2D BatCollider;
private Rigidbody2D rb;
void Start () {
rb = GetComponent<Rigidbody2D>();
}
void FixedUpdate () {
if(kickForce != 0)
{
float angle = Random.Range(0,20) * Mathf.Deg2Rad;
rb.AddForce(new Vector2(0.0f,
forceFactor * Mathf.Clamp(kickForce, 0.0f, tMax) * Mathf.Sin(angle)),
ForceMode2D.Impulse);
kickForce = 0;
}
prevVelocity = rb.velocity;
}
void Update(){
if(Input.GetKeyDown (KeyCode.Space))
{
kickStart = Time.time;
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
RaycastHit hit;
if (Physics.Raycast(ray, out hit))
{
if(hit.collider.name == "Ball") // Rename ball object to "Ball" in Inspector, or change name here
kickForce = Time.time - kickStart;
}
}
}
public void KickBall(){
BatCollider.enabled = true;
}
void OnCollisionEnter(Collision col)
{
if(col.gameObject.tag == "Ground") // Do not forget assign tag to the field
{
rb.velocity = new Vector2(prevVelocity.x,
-prevVelocity.y * Mathf.Clamp01(bounceFactor));
}
}
}
However, I am unable to kick the ball when I press the space key. The ball is just bouncing because of colliders. What am I missing?
Check my result:

I would advocate something more like this to start with. This is the script you would add onto your baseball bat.
Part 1:
using UnityEngine;
using System.Collections;
public class KickTheBall : MonoBehaviour
{
public float forceFactor = 10f;
private float kickForce = 50f;
void OnCollisionEnter(Collision col)
{
if(col.gameObject.tag == "Ball") // Do not forget assign tag to the field
{
rb = col.gameobject.GetComponent<Rigidbody>();
rb.AddForce(transform.right * kickForce);
}
}
}
I have simplified your AddForce function for demonstration purposes. Feel free to replace it with your more complex AddForce function if everything is working.
Part 2:
If you really want to include the part where holding the space button makes the hit stronger, then add this:
void Update()
{
if(Input.GetKey(KeyCode.Space))
{
kickForce += 0.5f;
}
}
and add at the end of the oncollisionenter
kickForce = 0;
What this will do is build up force while you hold the space button down. After a successful hit the force will reset to 0. So subsequent collisions will not result in a hit until the space button is held again.
Let me know if this did anything for you.

I solved the issue with the help of #TylerSigi. I updated my script file with these codes:
using UnityEngine;
using System.Collections;
public class KickTheBall : MonoBehaviour {
public float forceFactor = 10f;
private float kickForce = 0f;
private EdgeCollider2D BatCollider;
public GameObject Ball;
void Start () {
}
void Update()
{
if (Input.GetKey (KeyCode.Space)) {
kickForce = 1000;
} else {
kickForce = 0;
}
}
void OnTriggerEnter2D(Collider2D col)
{
if(col.gameObject.tag == "Enemy") // Do not forget assign tag to the field
{
Ball.GetComponent<Rigidbody2D>().AddForce(transform.right * kickForce);
}
}
}

Detect if enemy is facing Player

I am making a game in which if the distance is less than 2 and the enemy is facing the player, text comes up with a restart option. In the update there is an if and else statement which should detect if the enemy is behind or in front of the player. However, the in front option seems to be called once the distance is less than 2, regardless of if the player is facing the npc.
This script is attached to the Enemy:
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
public class EnemyFollow : MonoBehaviour {
Transform player;
Transform enemy;
public GameObject EnemyCaughtCam;
public Text SheCaughtYou;
public GameObject Restart;
public float Speed = 3f;
public float rotS = 3f;
public float sT = 3f;
NavMeshAgent nav;
float timeTillOptionsMenu = 3.0f;
// Use this for initialization
void Awake() {
player = GameObject.FindGameObjectWithTag ("MainCamera").transform;
//enemy = GameObject.FindGameObjectWithTag ("Enemy").transform;
nav = GetComponent<NavMeshAgent> ();
EnemyCaughtCam.SetActive(false);
SheCaughtYou.text = "";
}
// Update is called once per frame
void Update () {
nav.SetDestination (player.position);
DistanceDeath();
if (npcIsFacingPlayer (player)&& !playerIsFacingNpc(player))
print ("Behind");
else if (npcIsFacingPlayer (player)&& playerIsFacingNpc(player))
print ("In Front");
DistanceDeath ();
}
public void DistanceDeath(){
float distance = Vector3.Distance(player.transform.position,
transform.position);
if (distance < 2 ){
EnemyCaughtCam.SetActive(true);
SheCaughtYou.text = "SHE CAUGHT YOU!";
timeTillOptionsMenu -= Time.deltaTime;
if(timeTillOptionsMenu < 0)
{
Restart.SetActive(true);
}
}
}
public bool npcIsFacingPlayer(Transform other)
{
Vector3 toOther =
other.position - transform.position;
return (Vector3.Dot(toOther, transform.forward) > 0);
}
public bool playerIsFacingNpc(Transform other)
{
Vector3 toOther =
transform.position - other.position;
return (Vector3.Dot(toOther, other.forward) > 0);
}
}

First, you are missing some brackets, second there is an stra DistanceDeathcall, here is how your function Update is read:
// Update is called once per frame
void Update () {
nav.SetDestination (player.position);
/** what does the call do here? */
DistanceDeath();
if (npcIsFacingPlayer (player)&& !playerIsFacingNpc(player))
print ("Behind");
else if (npcIsFacingPlayer (player)&& playerIsFacingNpc(player))
print ("In Front");
/** are you missing brackets here? Distance Death is always called */
DistanceDeath ();
}

Unity 3D How to setup Turret Auto Aim? C#

what i't trying to achieve is have my turrent rotate and follow an "Enemy".
At the moment it detects the enemy but it is not rotating and I don't know why.
The bullet it a prefab i drag in, there has to be a better way to do this? Anyone have any suggestions please?
At the moment the bullet never triggers, but the log Shoot and does...and the rotate doesn't work.
Here is what i have
using UnityEngine;
using System.Collections;
public class TurretController : MonoBehaviour {
public Rigidbody bulletPrefab;
private Transform target;
private GameObject bullet;
private float nextFire;
private Quaternion targetPos;
void OnTriggerEnter(Collider otherCollider) {
if (otherCollider.CompareTag("Enemy"))
{
Debug.Log ("in");
target = otherCollider.transform;
StartCoroutine ("Fire");
}
}
void OnTriggerExit(Collider otherCollider) {
if (otherCollider.CompareTag("Enemy"))
{
Debug.Log ("out");
target = null;
StopCoroutine("Fire"); // aborts the currently running Fire() coroutine
}
}
IEnumerator Fire()
{
while (target != null)
{
nextFire = Time.time + 0.5f;
while (Time.time < nextFire)
{
// smooth the moving of the turret
targetPos = Quaternion.LookRotation (target.position);
transform.rotation = Quaternion.Slerp(transform.rotation, targetPos, Time.deltaTime * 5);
yield return new WaitForEndOfFrame();
}
// fire!
Debug.Log ("shoot");
bullet = Instantiate(bulletPrefab, transform.position, transform.rotation) as GameObject;
//bullet.rigidbody.velocity = transform.forward * bulletSpeed;
}
}
}
I tried to change the instantiate part by using this instead
bullet = (GameObject)Instantiate(bulletPrefab, transform.position, transform.rotation);
bullet.GetComponent<Bullet>().target = target.transform;
But then i just get errors like "InvalidCastException: Cannot cast from source type to destination type.
TurretController+c__Iterator0.MoveNext () (at Assets/Scripts/TurretController.cs:44)"

BTW, here's the turret rotation code I used in my project (shared with permission):
using UnityEngine;
using System.Collections;
using System.Collections.Generic;
public class Turret : MonoBehaviour
{
[SerializeField]
private float turnRateRadians = 2 * Mathf.PI;
[SerializeField]
private Transform turretTop; // the gun part that rotates
[SerializeField]
private Transform bulletSpawnPoint;
private Enemy target;
void Update()
{
TargetEnemy();
}
void TargetEnemy()
{
if (target == null || target.health <= 0)
target = Enemy.GetClosestEnemy(turretTop, filter: enemy => enemy.health > 0);
if (target != null)
{
Vector3 targetDir = target.transform.position - transform.position;
// Rotating in 2D Plane...
targetDir.y = 0.0f;
targetDir = targetDir.normalized;
Vector3 currentDir = turretTop.forward;
currentDir = Vector3.RotateTowards(currentDir, targetDir, turnRateRadians*Time.deltaTime, 1.0f);
Quaternion qDir = new Quaternion();
qDir.SetLookRotation(currentDir, Vector3.up);
turretTop.rotation = qDir;
}
}
}
class Enemy : MonoBehaviour
{
public float health = 0;
private static HashSet<Enemy> allEnemies = new HashSet<Enemy>();
void Awake()
{
allEnemies.Add(this);
}
void OnDestroy()
{
allEnemies.Remove(this);
}
/// <summary>
/// Get the closest enemy to some transform, optionally filtering
/// (for example, enemies that aren't dead, or enemies of a certain type).
/// </summary>
public static Enemy GetClosestEnemy(Transform referenceTransform, System.Predicate<Enemy> filter=null)
{
// Left as an exercise for the reader.
// Remember not to use Vector3.Distance in a loop if you don't need it. ;-)
// return allEnemies[0];
}
}

First problem: the bullet prefab. The variable type is RigidBody. If you want to treat it as a game object, the variable must be a game object. Or you can instantiate it, cast to RigidBody, then use the .gameObject accessor. Like this:
((RigidBody)Instantiate(theRigidbody)).gameObject
Second problem: start simple with the rotation. If it's not working, don't get fancy yet. Start with something like this (an instant rotation toward the target):
Vector3 targetDirection = target.transform.position - transform.position;
targetDirection.y = 0; // optional: don't look up
transform.forward = targetDirection;
If it works, then add small pieces of additional complexity until it does exactly what you want. And if you don't get things figured out, give me a shout (a comment) on Monday. I've written turret-aiming code (including a maximum rotation speed), and I don't think my boss would mind if I upload it.