Skip to content

Instantly share code, notes, and snippets.

Last active September 25, 2021 21:04
Show Gist options
  • Save samsheffield/2a8e58dc77d8b86f39aca1549be99721 to your computer and use it in GitHub Desktop.
Save samsheffield/2a8e58dc77d8b86f39aca1549be99721 to your computer and use it in GitHub Desktop.
Flapping movement
Here is a bonus Unity example for 2D Game Design F21. Let me know what else you need!
Full example: FlappyControl.cs
1. Flapping isn't exactly jumping. Our expectations of jumping in videogames tend to be much higher. This is dumb, bouncy, and messy (but fun!)
2. Your GameObject needs a Rigidbody2D component with Gravity Scale set to something other than 0.
3. The script interact's a lot with the Rigidbody2D properties Gravity Scale and Linear Drag. Experiment!
4. See full example for input management
// Add a vertical force (Vector2.up x force) immediately as an impulse:
rb2d.AddForce(Vector2.up * flapForce, ForceMode2D.Impulse);
// Vector2.up is shorthand for new Vector2(0f, 1f) which only applies this force on the y axis
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class FlappyControl : MonoBehaviour
// Variables which can be modified in the Inspector
public float xSpeed = .5f;
public float flapForce = 10f;
// Variables used only within this script
private Vector2 direction;
private Rigidbody2D rb2d;
private bool flap;
private void Start()
// Set this gameobject's tag to Player. You can also do this in the Inspector
gameObject.tag = "Player";
// Store a reference to the rigidbody2d component to use in this script
rb2d = GetComponent<Rigidbody2D>();
// Update is called once per frame
private void Update()
// Notice that only the x property is being set to an input's value (y is 0)
direction = new Vector2(Input.GetAxisRaw("Horizontal"), 0f);
// Check for a button press. "Jump" is the spacebar on a keyboard
if (Input.GetButtonDown("Jump") == true)
// if it is true... set the flap state so that it can be used in FixedUpdate
flap = true;
// FixedUpdate is for physics
private void FixedUpdate()
// Add an instant forces to the rigidbody2d. The forces are the input values * the xSpeed value
// Impulse applies forces immediately, which is not very realistically, but works great for a simple 2D game
rb2d.AddForce(direction * xSpeed, ForceMode2D.Impulse);
// If the flap state is true... Flap!
if(flap == true)
// AddForce always expects a Vector2 of force (x and y axes!) Vector2.up is shorthand for new Vector2(0f, 1f), so multiplying times flapForce only applies the for e on the y axis.
rb2d.AddForce(Vector2.up * flapForce, ForceMode2D.Impulse);
// Reset the flap state to false so we don't keep flapping
flap = false;
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment