Using Rigidbody.velocity stops Rigidbody.AddForce

Unity Engine
1

Hello everyone
I have recently come into a little problem when I decided to code in some movement. Whenever I try to jump (which uses Rigidbody.velocity) it will stop all of the movement which I use to move from side to side (uses Rigidbody.AddForce). Here is the code: (I’m using 2D by the way)

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class PlayerMove : MonoBehaviour
{
    public Rigidbody2D rb;
    public GameObject Player;
    public float RunSpeed = 10f;
    public BoxCollider2D hitbox;
    [SerializeField] LayerMask platformsLayerMask;

    public KeyCode A = KeyCode.A;
    public KeyCode D = KeyCode.D;
    public KeyCode W = KeyCode.W;
    void Start()
    {
        Player = GameObject.Find("Player");
        rb = Player.GetComponent<Rigidbody2D>();
        hitbox = Player.GetComponent<BoxCollider2D>();
    }

    // Update is called once per frame
    void Update()
    {
        if (IsGrounded() && Input.GetKeyDown(W))
        {
            float JumpForce = 12.5f;
            rb.velocity = Vector2.up * JumpForce;
        }
       
        if (Input.GetKey(A))
        {
            ForceChange(rb, Vector3.right * -RunSpeed, 2f);
        }
        if (Input.GetKey(D))
        {
            ForceChange(rb, Vector3.right * RunSpeed, 2f);
        }
       

    }
    public bool IsGrounded()
    {
        RaycastHit2D jumpDetect = Physics2D.BoxCast(hitbox.bounds.center, hitbox.bounds.size, 0f, Vector2.down, .01f, platformsLayerMask);
        return jumpDetect.collider != null;
       
    }

    public static void ForceChange(Rigidbody2D rb, Vector3 velocity, float force = 1f, ForceMode2D mode = ForceMode2D.Force)
    {
        if(force == 0 || velocity.magnitude == 0)
        {
            return;
        }

        velocity = velocity + velocity.normalized * 0.2f * rb.drag;

        force = Mathf.Clamp(force, -rb.mass / Time.fixedDeltaTime, rb.mass / Time.fixedDeltaTime);

        if(rb.velocity.magnitude == 0)
        {
            rb.AddForce(velocity * force, mode);
        }
        else
        {
            var velocityProjected = (velocity.normalized * Vector3.Dot(velocity, rb.velocity) / velocity.magnitude);
            rb.AddForce((velocity - velocityProjected) * force, mode);
        }
    }
}

I want to know if there is some way to fix this, and I feel that changing the rb.AddForce to rb.velocity won’t do the trick for me, because I want the speed to slowly rise before it reaches the maximum speed. Thanks in advance!

2

If you want to use rb.velocity you need grab the current velocity, modify its y component, then pass it back. Right now you’re setting the x and z components of its velocity to 0, hence it stopping in those directions.

Rough example:

Vector3 currentVel = rb.velocity;
currentVel += Vector3.up * JumpForce;
rb.velocity = currentVel;

This is just one of many ways to achieve this of course.

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