This snippet will show you how to make your character to an exact height.

Jumping is in nearly every game. Very often a entire game’s mechanics will revolve around jumping itself.

Here is a quick script on how to make an object in unity jump to a given height. NOTE: Some high school math may be required to understand the concepts, but not to copy and paste the snippet 😀

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

[RequireComponent(typeof(Rigidbody))]
public class PlayerComponent : MonoBehaviour
{
    // The height you want the player to jump
    public float jumpHeight = 10;

    private Rigidbody mRigidbody = null;

    // Start is called before the first frame update
    void Start()
    {
        mRigidbody = GetComponent<Rigidbody>();        
    }

    // Update is called once per frame
    void Update()
    {
        if (Input.GetMouseButtonDown(0))
        {
            // Maximum Altitude = vertical velocity squared / ( 2 * gravity )
            // Maxmium Altitude * 2 * gravity = Vertical velocicty squared
            // sqrt ( maximum altitute * 2 * gravity ) = vertical velocity
            mRigidbody.AddForce(Vector3.up * Mathf.Sqrt(2 * -Physics.gravity.y * jumpHeight), ForceMode.Impulse);
        }
    }
}

The magic happens here:

Mathf.Sqrt(2 * -Physics.gravity.y * jumpHeight)

Here is an explanation of where this comes from. The maximum height of a projectile can be calculated as:

h_max=v_vert²/2g

In this equation, h_max is the maximum height of the projectile (aka the height we want to jump), v_vert is the vertical velocity required to reach that height, and g is the force of gravity.

If we set our player’s vertical (y) velocity to v_vert it will reach h_max . We find v_vert by simply dividing h_max by 2g, then getting the square root of that value.

h_max=v_vert²/2g

h_max (2g)=v_vert²

sqrt(h_max (2g))=v_vert

These concepts can apply in any game engine, you would just have to adjust the script. The math would remain the same.

I hope this helps. Have fun!