How to invert gravity in Godot

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Godot Version

4.2

Question

How to invert gravity in Godot

Why doesnt spacebar invert gravity, it just jumps: extends CharacterBody2D

var speed = 600 # Horizontal movement speed
var ngraivty = -1000;
var gravity = 1000 # Gravity strength (pixels per second squared)

func _physics_process(delta):
# Apply gravity
if not is_on_floor():
velocity.y += gravity * delta

# Horizontal movement input
var horizontal_input = Vector2.ZERO
if Input.is_action_pressed("a"):
	horizontal_input.x -= 1
if Input.is_action_pressed("d"):
	horizontal_input.x += 1
velocity.x = horizontal_input.x * speed

# Jump input
if Input.is_action_just_pressed("space") and is_on_floor():
	velocity.y += ngraivty;

move_and_slide()
2

Because that code does not actually invert the gravity.

Keep in mind that _physics_process is called sixty times a second. Say that the character is on the floor and the player pressed the space bar:

# Jump input
if Input.is_action_just_pressed("space") and is_on_floor():
	velocity.y += ngraivty;

In that section of code, the character’s y-velocity is set to -1000. The character moves up and is no longer on the floor after move_and_slide is called. 1/60th of a second later, _physics_process is called again. Code is executed from the top:

if not is_on_floor():
	velocity.y += gravity * delta

The character is no longer on the floor, so we enter this if-statement and the character’s velocity is immediately set back to 1000 (i.e. moving down.) That is why your character appears to jump-- a sudden upward movement that lasts for approximately one frame, followed by an immediate drop down.

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