Third Person jump not working, Character freezes

Unity Engine
, , ,
1

I’m trying to figure out why my jump is not working for my 3rd person jump code. I’m currently getting a NaN on my jump velocity Vector3 whenever I press space, resulting in the character freezing wherever they are. I’m very new to this and I tried combining Brackey’s 3rd person movement tutorial with his jump from his first person movement tutorial but the math confuses me.

using System;
using UnityEngine;
using UnityEngine.TextCore.Text;
using UnityEngine.UI;

public class Player : MonoBehaviour
{
    public CharacterController controller;
    public Transform cam;
    public float Speed = 6f;
    
    public float gravity = -9.81f;
    
    public float turnSmoothTime = 0.1f;
    float turnSmoothVelocity;
    
    public Transform groundCheck;
    public float groundDistance = 0.4f;
    public LayerMask groundMask;
    
    public bool isGrounded;
    
    public Vector3 velocity;
    public Vector3 movDir;
    private Vector3 moveNormalized;
    private Vector3 finalVelocity;

    void Update()
    {
        float horizontal = Input.GetAxis("Horizontal");
        float vertical = Input.GetAxis("Vertical");
        Vector3 direction = new Vector3(horizontal, 0f, vertical).normalized;
        
        isGrounded = Physics.CheckSphere(groundCheck.position, groundDistance, groundMask);

        velocity.y += gravity * Time.deltaTime;

        if (isGrounded && velocity.y < 0)
        {
            velocity.y = -2f;
        }
        
        if (Input.GetButtonDown("Jump") && isGrounded)
        {
            velocity.y = Mathf.Sqrt(velocity.y * -9.81f * gravity);
        }
        
        if (direction.magnitude > 0.1f)
        {
            float targetAngle = Mathf.Atan2(direction.x, direction.z) * Mathf.Rad2Deg + cam.eulerAngles.y;
            float angle = Mathf.SmoothDampAngle(transform.eulerAngles.y, targetAngle, ref turnSmoothVelocity, turnSmoothTime);
            transform.rotation = Quaternion.Euler(0f, angle, 0f);
            
            movDir = Quaternion.Euler(0f, targetAngle, 0f) * Vector3.forward;
            moveNormalized = movDir.normalized * Speed;
            finalVelocity = new Vector3(moveNormalized.x, velocity.y, moveNormalized.z);
            controller.Move(finalVelocity * Time.deltaTime);
        }
    }
}
2

Your gravity field is public, thus serialized. Is it perhaps serialized as zero? If it’s going to be a constant value, perhaps declare it as public const float Gravity = -9.81f; to prevent serialisation being an issue.

That said, a simple case of debugging. Figure out at which point the NaN arises, and work out what’s causing it.

3

Your character only moves when the player presses a key and so gravity won’t work when the player isn’t trying to move. Here’s a simplified version:

using UnityEngine;
public class Player : MonoBehaviour
{
    public CharacterController controller;
    public float speed = 6f;
    public float gravity = -9.81f;
    public float turnSpeed = 4;
    public Vector3 velocity;

    void Update()
    {
        float horizontal = Input.GetAxis("Horizontal");
        float vertical = Input.GetAxis("Vertical");
        Vector3 direction = new Vector3(horizontal, 0f, vertical).normalized;

        velocity.y += gravity * Time.deltaTime;

        if (controller.isGrounded && velocity.y < 0)
            velocity.y = -2f;

        if (Input.GetButtonDown("Jump") && controller.isGrounded)
            velocity.y = 7;

        transform.Rotate(0, horizontal * turnSpeed, 0);

        direction = transform.TransformDirection(direction) * speed;
        Vector3 finalVelocity = new Vector3(direction.x, velocity.y, direction.z);
        controller.Move(finalVelocity * Time.deltaTime);
    }
}
1 Like