Variable jump in C#

Unity Engine
1

Hi, I have a code which is basically perfect for jump and doublejump but the character has a fixed jumping height. What I’m looking for is a “super mario jumping effect”. Press the jump button really fast, jump a little, keep it pressed , jump a little higher and so on. (hope I explained myself well, if not, I’ll try again).

this is the code

using UnityEngine;
using System.Collections;

public class CharController : MonoBehaviour
{
    [SerializeField] private float m_JumpForce;
    [SerializeField] private float moveSpeed;
    [SerializeField] private LayerMask m_WhatIsGround;
   
    private Transform m_GroundCheck;
    private Transform m_GroundCheckS;
    const float k_GroundedRadius = .15f;
   
    private bool cir_Grounded;
    private bool cir_GroundedS;
    private bool is_Grounded;
    private bool doubleJump;
   
    private Rigidbody2D m_Rigidbody2D;
   
    // Use this for initialization
    void Start()
    {
        m_GroundCheck = transform.Find("groundCheck");
        m_GroundCheckS = transform.Find("groundCheckS");
        m_Rigidbody2D = GetComponent<Rigidbody2D>();   

        gameObject.transform.position = new Vector2 (10, 30);
    }
   
    void Update()
    {
        cir_Grounded = false;
        cir_GroundedS = false;
        is_Grounded = false;

        Collider2D[] colliders = Physics2D.OverlapCircleAll(m_GroundCheck.position, k_GroundedRadius, m_WhatIsGround);
        for (int i = 0; i < colliders.Length; i++)
        {
            if (colliders[i].gameObject != gameObject)
                cir_Grounded = true;
        }
       
        Collider2D[] colliders2 = Physics2D.OverlapCircleAll(m_GroundCheck.position, k_GroundedRadius, m_WhatIsGround);
        for (int i = 0; i < colliders2.Length; i++)
        {
            if (colliders2[i].gameObject != gameObject)
                cir_GroundedS = true;
        }
       
        if (cir_GroundedS && cir_Grounded)
        {
            is_Grounded = true;
        }

        //m_Rigidbody2D.velocity = new Vector2 (moveSpeed, m_Rigidbody2D.velocity.y); //Moves the player horizontally

        if (Input.GetKeyDown ("space"))
        {
            if (is_Grounded)
            {
                is_Grounded = false;
                cir_Grounded = false;
                cir_GroundedS = false;
                m_Rigidbody2D.velocity = new Vector2(m_Rigidbody2D.velocity.x, 0);
                m_Rigidbody2D.AddForce (new Vector2(0f, m_JumpForce));
                doubleJump = true;
            }
            else if (doubleJump)
            {
                m_Rigidbody2D.velocity = new Vector2(m_Rigidbody2D.velocity.x, 0);
                m_Rigidbody2D.AddForce (new Vector2(0f, m_JumpForce));
                doubleJump = false;
            }
        }
    }
}

Thanks for the attention

2

Try something like:

float jumpForce = 3f;

//inside FixedUpdate
if(Input.GetButton("Jump"))
{
    m_Rigidbody2D.AddForce(new Vector2(0f, jumpForce));
    jumpForce -= .5f //or whatever amount
    if(jumpForce < 0f)
        jumpForce = 0f;
}

//inside Update
if(Input.GetButtonUp("Jump"))
{
    jumpForce = 3f; //go back to original power
}

This is just off the top of my head, but should get you going the right direction

1 Like
3

Put it inside FixedUpdate for results that won’t vary wildly depending on framerate.

1 Like
4

Hah, good point! I wrote the code out quickly in notepad

EDIT: The GetButton should be in fixed update, however the GetButtonUp should be in regular update since FixedUpdate can miss down and up checks

5

Thank you for replying, as soon as I get them working I’ll let you know. The solution concept is so easy, thanks again.

6

I know, double post but need to ask you an opinion (actually if we can discuss about a code).
Basically this it the Gamasutra page I took the idea of how to make a variable height jump the first time: http://www.gamasutra.com/blogs/DanielFineberg/20150825/244650/Designing_a_Jump_in_Unity.php

this is the code in short (a simplified version of it):

void Update()
{
    if(jumpButtonDown && !jumping)
    {
        jumping = true;
        StartCoroutine(JumpRoutine());
    }
}

IEnumerator JumpRoutine()
{
    rigidbody.velocity = Vector2.zero;
    float timer = 0;
     
    while(jumpButtonPressed && timer < jumpTime)
    {
        //Calculate how far through the jump we are as a percentage
        //apply the full jump force on the first frame, then apply less force
        //each consecutive frame
         
        float proportionCompleted = timer / jumpTime;
        Vector2 thisFrameJumpVector = Vector2.Lerp(jumpVector, Vector2.zero, proportionCompleted);
        rigidbody.AddForce(thisFrameJumpVector);
        timer += Time.deltaTime;
        yield return null;
    }
     
    jumping = false;
}
}

So, how in the world can they get the button pressed and put it in a while loop without make Unity crash (every time I tried it crashed). To compare the “while loop” with an “if statement” (that holds a “input.getkey”), the while loop never ends until the conditions are met, but what about the “if statement”? does it exits every frame but still holding the condition Input.getkey?

7

Can somebody please tell me what this ‘jumpVector’ is and which values it should have? Plus, the way this C# code on gamasutra is written, it does not work for me at all. I change that first rigidbody.velocity to the new AddForce standard but the player never reacts to the pressed button. Only to the initial first frame push. Please help.

8

It’s the direction you’re jumping in!

probably something along the lines of:

Vector2.up + currentVelocity.x;

Note that I’m not normalizing the vector. That gives Mario rules, where a standing jump and a running jump gives the same height.

9

I stumbled across this tutorial series recently while looking for an alternative solution to my problem.

I remember it having a intuitive variable jump solution. I recommend a watch.

Kind Regards,
Joe