Why is my just_pressed sometimes ignored?

is_action_just_pressed in _physics_process only returns true on the physics tick when the press happened. If the press lands between physics ticks, the boolean clears before _physics_process reads it. Buffer in _input or use the unhandled_input callback.

What's the buffer pattern?

In _input(event), set a member 'jump_buffered = true'. In _physics_process, check the buffer and reset. Lasts up to one physics tick; press always seen.

Should I use _process for input?

Reading is_action_just_pressed in _process can also miss between frames. The buffer-from-_input pattern is the most reliable for tick-precise input handling.

Fix: Godot 4 Input.is_action_just_pressed Missed in _physics_process

Quick answer: Buffer the press in _input(): set jump_buffered = true. Read and clear in _physics_process. Press never lands between ticks because _input fires immediately on the event.

Player taps Jump quickly, character doesn’t jump. is_action_just_pressed cleared between physics ticks because the press happened off-tick.

The Symptom

Quick taps occasionally don’t register. Holding the key long enough always works because is_action_pressed is read each tick.

The Fix

extends CharacterBody2D

var jump_buffered := false

func _input(event: InputEvent) -> void:
    if event.is_action_pressed("jump"):
        jump_buffered = true

func _physics_process(delta: float) -> void:
    if jump_buffered and is_on_floor():
        velocity.y = JUMP_VELOCITY
    jump_buffered = false

_input runs immediately when the event arrives, regardless of physics tick timing. Buffer survives until the next physics tick, which always sees and clears it.

Verifying

Tap fast. Every tap should jump. Without the buffer: occasional miss. With: 100% pickup.

“Capture in _input. Consume in _physics_process. Never miss.”

Related Issues

For input deadzone, see deadzone. For shortcut context, see shortcut.

Buffer the input. Tick reads cleanly.