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Unity player movement on moving planet

I am making a game involving orbital physics. I was successfully able to implement this with a slightly modified version of Brackeys gravity tutorial https://youtu.be/Ouu3D_VHx9o, this is the code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class gravity : MonoBehaviour
{
public GameObject self;
public Rigidbody rb;
public Vector3 initialVelocity;
const float G = 66.74f;
public static List<gravity> Attractors;
public bool isAttractable;
private void Awake()
{
rb.AddForce(initialVelocity);
}
private void FixedUpdate()
{
//planets
if (isAttractable == false)
{
foreach (gravity attractor in Attractors)
{
if (attractor != this)
Attract(attractor);
}
}
//players, spaceships, astroids, ect
if (isAttractable == true)
{
foreach (gravity attractor in Attractors)
{
if (attractor != this)
Attract(attractor);
}
}
}
void OnEnable()
{
if( isAttractable == false)
{
if (Attractors == null)
Attractors = new List<gravity>();
Attractors.Add(this);
}
}
void OnDisable()
{
if (isAttractable == false)
{
Attractors.Remove(this);
}
}
void Attract(gravity objToAttract)
{
Rigidbody rbToAttract = objToAttract.rb;
Vector3 direction = -1 * (rb.position - rbToAttract.position);
Vector3 Force = direction.normalized * (G * ((rb.mass * rbToAttract.mass) / direction.sqrMagnitude));
rb.AddForce(Force);
}
public GameObject GetClosestPlanet()
{
GameObject close = null;
float minDist = Mathf.Infinity;
foreach (gravity attracor in Attractors)
{
float dist = Vector3.Distance(attracor.transform.position, transform.position);
if (dist < minDist)
{
close = attracor.transform.gameObject;
minDist = dist;
}
}
return close;
}
}
Then for player movement I used (and modified) Sebastian Lagues tutorial https://youtu.be/TicipSVT-T8,
this resulted in this code for the player controller:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class playerController : MonoBehaviour
{
public float mouseSensitivityX = 250f;
public float mouseSensitivityY = 250f;
Transform cameraT;
float verticalLookRot;
private Rigidbody rb;
Vector3 moveAmount;
Vector3 smootgMoveVelocity;
public float moveSpeed = 15;
public float jumpForce = 220;
public LayerMask groundedMask;
public bool grounded;
public GameObject currentPlanet;
private gravity playerGravity;
private void Awake()
{
rb = GetComponent<Rigidbody>();
playerGravity = GetComponent<gravity>();
Cursor.lockState = CursorLockMode.Locked;
cameraT = Camera.main.transform;
}
void Update()
{
currentPlanet = playerGravity.GetClosestPlanet();
//camera
transform.Rotate(Vector3.up * Input.GetAxis("Mouse X") * Time.deltaTime * mouseSensitivityX);
verticalLookRot += Input.GetAxis("Mouse Y") * Time.deltaTime * mouseSensitivityY;
verticalLookRot = Mathf.Clamp(verticalLookRot, -60, 60);
cameraT.localEulerAngles = Vector3.left * verticalLookRot;
//move input
Vector3 moveDir = new Vector3(Input.GetAxisRaw("Horizontal"), 0, Input.GetAxisRaw("Vertical")).normalized;
Vector3 targetMoveAmount = moveDir * moveSpeed;
moveAmount = Vector3.SmoothDamp(targetMoveAmount, targetMoveAmount, ref smootgMoveVelocity, .15f);
//level on planet
if(currentPlanet != null)
{
transform.rotation = Quaternion.FromToRotation(transform.up, (transform.position - currentPlanet.transform.position).normalized) * transform.rotation;
}
//jump
if (Input.GetButtonDown("Jump"))
{ if(grounded)
{
rb.AddForce(transform.up * jumpForce);
print("u jumped");
}
}
}
private void FixedUpdate()
{
//move
rb.MovePosition(rb.position + transform.TransformDirection(moveAmount) * Time.fixedDeltaTime);
//check if on ground
Ray ray = new Ray(transform.position, -transform.up);
RaycastHit hit;
grounded = Physics.Raycast(ray, out hit, transform.localScale.y + 1.1f, groundedMask);
}
}
Now for the issue, this systems works fine when the planet the player is walking on is stationary. As in there are no other attracting bodys in the system and the planet has no initial velocity. However if the planet is moving the player will bounce up and down uncontrollably and will not be able to walk a certain distance away from the planets farthest point from its direction of movement. Here is a recording of this: https://youtu.be/noMekosb7CU
Does anyone know what is causing the bouncing and walking restrictions and how I can fix it?
Some notes on suggested solutions that haven't worked:
-set the planet as the players parent object, same results
-increase players mass, same results
-set the players velocity to += the planets velocity, same results or player goes into infinity

For me it seems to be working "correctly".
Looking like your player is attracted correctly and when the planet moves, your player is quickly moving towards the planet.
I think you could temporarily assign the player as a child gameobject to the planet he's walking on and he should probably move correctly along the planet coordinates and not on global coordinates. (If it works, you could just always assign the player as a child gameObject to every new planet that he visits)

Problems With Collision Detection (OnCollisionEnter2D)

I am starting to make a 2D platformer. I figured out how to make the character jump, but when I tried to add in Collision Detection to make it to where the player can only jump on the ground, it wouldn't work. Here's my code:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class NewBehaviourScript : MonoBehaviour
{
Vector2 newPosition = new Vector2(0, 7);
float movementSpeed = 5f;
float jumpForce = 10f;
public bool isGrounded;
// Start is called before the first frame update
void Start()
{
GetComponent<Rigidbody2D>().MovePosition(newPosition);
}
// Update is called once per frame
void Update()
{
if (Input.GetKey(KeyCode.A))
{
Vector2 position = this.transform.position;
position.x -= movementSpeed * Time.deltaTime;
this.transform.position = position;
}
if (Input.GetKey(KeyCode.D))
{
Vector2 position = this.transform.position;
position.x += movementSpeed * Time.deltaTime;
this.transform.position = position;
}
if (Input.GetKey(KeyCode.Space) && isGrounded == true)
{
Vector2 position = this.transform.position;
position.y += jumpForce * Time.deltaTime;
this.transform.position = position;
isGrounded = false;
}
}
void OnCollisionEnter2D(Collision2D other)
{
isGrounded = true;
}
}

Sometimes this is problem of the collider that touches the ground. Try to make it higher, lower and try again. I had the same problem once and the solution was just adjusting the collider. Some times the collider is too low, so when you jump it touches the ground again so it becomes true and immediately stops jumping.

No that wont do it. Try adding a Debug.Log(isGrounded) inside OnCollisionEnter2D() so you can see when it happens exactly maybe that will help you. By the way you haven't put any conditions inside the OnCollisionEnter2D() which means anything that enters it's collider will make isGrounded = true; .

Rotate enemy character to see player character

I am making the enemy character to follow the player character.
In the FixedUpdate method the enemy character move toward the player character,
then in the Update method character rotates to the player character.
However, with this script, somehow enemy character is just nudging and gets stuck.
Where is the mistake, what's wrong???
public class enemy : MonoBehaviour
{
GameObject tObj;
private Vector3 latestPos;
public string targetObjectName;
public float speed = (float)1.0;
void Start()
{
tObj = GameObject.Find("player");
latestPos = transform.position;
}
void Update()
{
Vector3 diff = transform.position - latestPos;
latestPos = transform.position;
if (diff.magnitude > 0.01f)
{
transform.rotation = Quaternion.LookRotation(diff);
}
}
void FixedUpdate(){
Vector3 dir = (tObj.transform.position - this.transform.position).normalized;
float vx = dir.x * speed;
float vz = dir.z * speed;
this.transform.Translate((float)(vx / 50.0),0,(float)(vz / 50.0));
}
}

Use Package Manager "Standard Assets", Inside Unity put two FPSController one should be Player and the second can be Enemy.
I know this does not answers your question but its a faster way to ad Enemy.
AI Settings
Just remove the camera, Audio Source and First Person Controller Script as in image.
The Code for AI:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class FollowAI : MonoBehaviour
{
public CharacterController _controller;
public Transform target;
public GameObject Player;
[SerializeField]
float _moveSpeed = 2.0f;
// Use this for initialization
void Start()
{
}
// Update is called once per frame
void Update() {
Vector3 direction = target.position - transform.position;
direction = direction.normalized;
Vector3 velocity = direction * _moveSpeed;
_controller.Move(velocity * Time.deltaTime);
Vector3 lookVector = Player.transform.position - transform.position;
lookVector.y = transform.position.y;
Quaternion rot = Quaternion.LookRotation(lookVector);
transform.rotation = Quaternion.Slerp(transform.rotation, rot, 1);
}
}

How to make my 2D character 'look' or flip in the direction he is moving?

I'm a total newbie in Unity and I'm learning/making my first game, which will be a platformer. I want to get the movement perfect first. I've added a simple script that enables the player to move and jump.
Here it is:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class NewBehaviourScript : MonoBehaviour{
public float jumpspeed = 5f;
public float speed = 5f;
Rigidbody2D rb;
GameObject character;
// Start is called before the first frame update
void Start()
{
}
void Awake(){
rb = gameObject.GetComponent<Rigidbody2D>();
}
// Update is called once per frame
void Update()
{
if (Input.GetKeyDown(KeyCode.Space)){
Jump();
}
Vector3 move = new Vector3(Input.GetAxis("Horizontal"), 0f, 0f);
transform.position += move *Time.deltaTime * speed;
}
void Jump(){
rb.AddForce(new Vector2(0f, jumpspeed), ForceMode2D.Impulse);
}
}
Now, I want the character to face in the direction in which it moves. The png is facing to the right by default.
How can I do that? Also, can I make my movement script better?
Thanks in advance!

I typically do this using code like this based off a bool.
void FlipSprite()
{
isFacingRight = !isFacingRight;
Vector3 theScale = transform.localScale;
theScale.x *= -1;
transform.localScale = theScale;
}

How Do I Shoot a Projectile into the Direction the Player is Facing?

I am creating a 2D side-scroller video game in Unity using c#. I have created the script that makes the player face the direction that the arrow key that was pressed was pointing to (when the right arrow is pressed, the player faces right. When the left arrow is pressed, the player faces left).
However, I cannot figure out how to make the harpoon that the player shoots point in the direction the player is facing. I have found many questions on Stack Overflow asking questions like this, but none of their answers worked for me.
Can anyone please tell me how to make the harpoon the player shoots face the direction the player is facing? Thanks in advance!
Here is my code that I use-
PLAYER SCRIPT
using UnityEngine;
using System.Collections;
public class playerMove : MonoBehaviour {
// All Variables
public float speed = 10;
private Rigidbody2D rigidBody2D;
private GameObject harpoon_00001;
private bool facingRight = true;
void Awake () {
rigidBody2D = GetComponent<Rigidbody2D>();
harpoon_00001 = GameObject.Find("harpoon_00001");
}
void Update () {
if (Input.GetKeyDown(KeyCode.LeftArrow) && !facingRight) {
Flip();
}
if (Input.GetKeyDown(KeyCode.RightArrow) && facingRight) {
Flip();
}
}
void Flip () {
facingRight = !facingRight;
Vector3 theScale = transform.localScale;
theScale.x *= -1;
transform.localScale = theScale;
}
void FixedUpdate () {
float xMove = Input.GetAxis("Horizontal");
float yMove = Input.GetAxis("Vertical");
float xSpeed = xMove * speed;
float ySpeed = yMove * speed;
Vector2 newVelocity = new Vector2(xSpeed, ySpeed);
rigidBody2D.velocity = newVelocity;
if (Input.GetKeyDown("space")) {
GetComponent<AudioSource>().Play();
Instantiate(harpoon_00001,transform.position,transform.rotation);
}
}
}
HARPOON SCRIPT
using UnityEngine;
using System.Collections;
public class harpoonScript : MonoBehaviour {
// Public variable
public int speed = 6;
private Rigidbody2D r2d;
// Function called once when the bullet is created
void Start () {
// Get the rigidbody component
r2d = GetComponent<Rigidbody2D>();
// Make the bullet move upward
float ySpeed = 0;
float xSpeed = -8;
Vector2 newVelocity = new Vector2(xSpeed, ySpeed);
r2d.velocity = newVelocity;
}
void Update () {
if (Input.GetKeyDown(KeyCode.LeftArrow)) {
float xSpeed = -8;
}
if (Input.GetKeyDown(KeyCode.RightArrow)) {
float xSpeed = 8;
}
}
void OnTriggerEnter2D(Collider2D other) //hero hits side of enemy
{
Destroy(other.gameObject.GetComponent<Collider2D>()); //Remove collider to avoid audio replaying
other.gameObject.GetComponent<Renderer>().enabled = false; //Make object invisible
Destroy(other.gameObject, 0.626f); //Destroy object when audio is done playing, destroying it before will cause the audio to stop
}
}

You already defining a variable facingRight to know the direction of the the player. You can use that knowledge to control the harpoon.
For example:
// this line creates a new object, which has harpoonScript attached to it.
// In unity editor, you drag and drop this prefab(harpoon_00001) into right place.
// transform.position is used for the starting point of the fire. You can also add +-some_vector3 for better placement
// Quaternion.identity means no rotation.
harpoonScript harpoon = Instantiate(harpoon_00001,transform.position, Quaternion.identity) as harpoonScript;
// Assuming harpoon prefab already facing to right
if (!facingRight) {
// Maybe, not required
harpoon.transform.eulerAngles = new Vector3(0f, 0f, 180f); // Face backward
Vector3 theScale = harpoon.transform.localScale;
theScale.y *= -1;
harpoon.transform.localScale = theScale; // Flip on y axis
}