how do i make something which moves with Velocity jump in Unity? - unity3d

Question

I was hoping I could get some help! I've been trying to make a platformer using velocity to move but I can't find a good way to do jumping using the system. Every frame the velocity's y just resets itself and I don't know how to create a jump. I have tried using ForceMode.VelocityChange and I have tried to write out equations. The player falls extremely slowly even with gravity turned on.
playerBody.AddForce(Vector3.up * jumpForce, ForceMode.VelocityChange);
I have the same issues when I try to set the y velocity to change with gravity
float MoveDirectionY = jumpForce * Physics.gravity.y;
enter image description here
Nothing seems to be working here. When i play the game gravity still pulls the object down slowly but if i turn off gravity it doesnt pull the object down at all.
The game does log the statement letting me know that it does know the space button was pressed.alt text
I want to also provide my code here:
using System.Collections;
using System.Collections.Generic;
using System.Transactions;
using Unity.Collections.LowLevel.Unsafe;
using UnityEngine;
public class PlayerMovement : MonoBehaviour
{
[SerializeField] private Rigidbody playerBody;
[SerializeField] private Vector3 inputVector;
[SerializeField] public float speed = 0.01f;
[SerializeField] public bool jump;
[SerializeField] private float turnSpeed = 45;
[SerializeField] public float jumpForce = 35000f;
[SerializeField] private bool isOnGround = true;
[SerializeField] float enemyPushForce = 100;
public int ingredient;
public GameManager gameManager;
public camSwitch cs;
public float horizontalInput;
public float verticalInput;
float playerFacingAngleY;
private GameObject FocalPoint;
// Start is called before the first frame update
void Start()
{
//Just making sure we have the rigid body of the game object the script is attached to so we can move it later
playerBody = gameObject.GetComponent<Rigidbody>();
FocalPoint = GameObject.Find("Focal Point");
}
// Update is called once per frame
//This is where the player script should be realizing we are using inputs
void Update()
{
horizontalInput = Input.GetAxis("Horizontal");
verticalInput = Input.GetAxis("Vertical");
playerFacingAngleY += horizontalInput * turnSpeed;
Vector3 playerFacingDirection = new Vector3(0, playerFacingAngleY, 0);
playerBody.rotation = Quaternion.Euler(playerFacingDirection);
float moveDirectionX = (FocalPoint.transform.position.x - gameObject.transform.position.x) *speed * verticalInput * Time.deltaTime;
float MoveDirectionY = jumpForce * Physics.gravity.y;
float moveDirectionZ = (FocalPoint.transform.position.z - gameObject.transform.position.z) * speed * verticalInput * Time.deltaTime;
Vector3 moveDirection = new Vector3(moveDirectionX, MoveDirectionY, moveDirectionZ);
playerBody.velocity = moveDirection;
if (Input.GetKeyDown(KeyCode.Space) && isOnGround == true)
{
playerBody.AddForce(Vector3.up * jumpForce, ForceMode.VelocityChange);
isOnGround = false;
print("player has jumped");
}
}
private void OnCollisionEnter(Collision collision)
{
isOnGround = true;
if (collision.gameObject.tag == "Enemy")
{
Debug.Log("Player ran into an enemy");
if (cs.inSky == true)
{
speed = 0;
}
else
{
speed = 10;
}
}
else if (collision.gameObject.tag == "Ingredient")
{
Debug.Log("Player collided with an ingredient");
collision.gameObject.SetActive(false);
ingredient++;
}
else if (collision.gameObject.tag == "Ground") {
isOnGround = true;
print("player has hit the ground");
}
}
}

Answer 1

Do not play with rigidbody in Update method. Use FixedUpdate() instead.
In addition, do not change velocity using rb.velocity = ... but use rigibody.AddForce() method. Try something like this:
void FixedUpdate() //using rigidbody? => ONLY FIXEDUPDATE
{
horizontalInput = Input.GetAxis("Horizontal");
verticalInput = Input.GetAxis("Vertical");
playerFacingAngleY += horizontalInput * turnSpeed;
Vector3 playerFacingDirection = new Vector3(0, playerFacingAngleY, 0);
playerBody.rotation = Quaternion.Euler(playerFacingDirection);
float moveDirectionX = (FocalPoint.transform.position.x - gameObject.transform.position.x) *speed * verticalInput * Time.deltaTime;
float moveDirectionZ = (FocalPoint.transform.position.z - gameObject.transform.position.z) * speed * verticalInput * Time.deltaTime;
Vector3 moveDirection = new Vector3(moveDirectionX, 0.0f, moveDirectionZ); //0.0f - just turn on gravity in rigidbody component or you can change it if you want some additional Vertical force
playerBody.AddForce(moveDirection, ForceMode.VelocityChange); //force mode change to whatever you want
if (Input.GetKeyDown(KeyCode.Space) && isOnGround == true)
{
playerBody.AddForce(Vector3.up * jumpForce, ForceMode.VelocityChange);
isOnGround = false;
print("player has jumped");
}
}