Input.parse_input_event turns into an infinite loop

darknova · August 30, 2026, 5:55am

Godot Version

v4.7.2.stable.official [ed1daf0bf]

Running on macOS 26.6.2

Context and Goal

I’m prototyping a turn based, player-vs-bots game (not multiplayer).

When a player taps a key, their avatar and all the enemies execute for their turn. The animations for these turn last for a quarter of a second, at which point the player can tap a key again for the next turn to happen. Also, if the player is holding the same key down when the animation finishes, then that action should re-fire.

Code

In _unhandled_input, I check for the action (&Move) and move the position of my avatar via a tween. At the end of the tween I call end_tween with the action that was just animated.

The boolean is_tweening is used to stop this code processing a new action while and existing action is being animated. If I didn’t do this, the avatar would move off the grid spots.

Regardless of whether is_tweening is true or not, I set_input_as_handled for valid actions.

Print calls are for debugging/tracing purposes.

func _unhandled_input(event: InputEvent) -> void:
	
	print( "UNHANDLED INPUT ", event.to_string() )
	
	if event is InputEventAction:
		var e = event as InputEventAction
		print( " ACTION EVENT WITH STRENGTH ", e.strength )
	
	if event.is_action_pressed( &"Move" ):
		
		if not is_tweening:
			
			is_tweening = true
			
			var t : Tween = create_tween()
			
			t.tween_property( avatar, "position", 2.0, 0.250 )
			t.tween_callback( end_tween.bind( &"Move" ) ) 
		
		current_viewport.set_input_as_handled()

The code for end_tween turns is_tweening off and then checks to see if the provided action_name is still being pressed. If so, it creates a new InputEvent and issues it using Input.parse_input_event.

The strength_counter variable starts with a value of 1.0 and is decremented each time I create a new InputEvent. This is purely for debugging purposes so I could check whether I was getting new events or somehow reprocessing the first event over and over.

Print calls are for debugging/tracing purposes.

func end_tween( action_name: StringName ) -> void:
	
	is_tweening = false
	
	print( "TWEEN ENDED FOR ACTION ", action_name )
	
	if Input.is_action_pressed( action_name ):
		
		var event : InputEvent = InputEventAction.new()
		
		event.action   = action_name
		event.pressed  = true
		
		event.strength = str_counter
		
		str_counter -= 0.01
		
		Input.parse_input_event( event )
		
		print( "BUTTON STILL DOWN FOR ACTION ", action_name, ". CREATED NEW ACTION WITH STRENGTH", str_counter )
		
	else:
		
		print( "BUTTON NO LONGER DOWN FOR ACTION ", action_name )

Bug

When I tap the key once. Everything works fine.

UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON NO LONGER DOWN FOR ACTION Move

When I tap the key twice, fast enough. Everything works fine.

UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON NO LONGER DOWN FOR ACTION Move

When I tap the key twice, slow enough. Everything works fine.

UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON NO LONGER DOWN FOR ACTION Move
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON NO LONGER DOWN FOR ACTION Move

When I press and hold, and trigger the creation of an InputEvent things go wrong.

UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.99
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 1.0
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=true, echo=true
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.98
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.99000000953674
UNHANDLED INPUT InputEventKey: keycode=87 (W), mods=none, physical=false, location=unspecified, pressed=false, echo=false
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.97
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.98000001907349
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.96
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.97000002861023
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.95
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.95999997854233
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.94
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.94999998807907
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.93
UNHANDLED INPUT InputEventAction: action="Move", pressed=true
 ACTION EVENT WITH STRENGTH 0.93999999761581
TWEEN ENDED FOR ACTION Move
BUTTON STILL DOWN FOR ACTION Move. CREATED NEW ACTION WITH STRENGTH0.92

As you can see, I get a pressed event, an echo event, and a released event, but the code in end_tween continues to see the action as pressed, causing a loop.

Note also, that the strength changes as expected, meaning we really are creating new events.

Also, when I watch it run, I can see that the logs are printed out at quarter second intervals.

Question

What am I misunderstanding about this functionality?

I do have another way of re-writing this code so that I don’t have to use Input.parse_input_event which I’ll try. But I’d still like to know what I’ve done wrong here.

silocoder · August 30, 2026, 6:12am

Have you tried

Input.is_action_just_pressed(action_name)

darknova · August 30, 2026, 8:23am

That has the opposite effect. Now holding down the key doesn’t cause the continued forward movement even while the key remains down.

The key taps still work, though.

athousandships · August 30, 2026, 8:27am

Parsing the input event marks the event as pressed but you never release it

darknova · August 30, 2026, 9:55am

Oh. Yeah. That is blindingly obvious in retrospect.

Thanks.

Now I have two pieces of code that work.

For people who find this, the solution was to add the following after I created the previous InputEvent:

		var event_up : InputEvent = InputEventAction.new()
		
		event_up.action   = action_name
		event_up.pressed  = false
		
		Input.parse_input_event( event_up )