Input Events and Viewports

JosephAustin

This might be a GUI problem but my situation involves a lot of moving parts, so I'm going to ask generally to be sure. Basically, it amounts to this: keyboard and mouse event propagation gets wacky when you wrap a Viewport in a ViewportContainer within a UI. I'm trying to make an in-game map editor with a TileMap wrapped in a GUI like so:

Control - Container (some buttons here) - FileDialog (opens and saves a file) - ViewportContainer

And ViewportContainer's children - TileMap <- where the trouble script is - Camera

When the FileDialog is open, a script on my TileMap gets ALL events on _input, instead of them getting blocked on the way down. The FileDialog is exclusive and set to STOP for its filter, so this is weird to me. Mouse and keyboard both bleed through.

Using unhandled_input causes key release events to still trigger, but not presses (ooookay). It also catches mouse events. gui_input doesnt work at all, but I expected that.

Using Input.is_action_pressed is identical to the _input method. It still catches the action no matter what else is going on. :/

I DID solve it, but in an ugly way that compels me to ask if there's something better. Basically, I added this script to the ViewportContainer:

func _gui_input(event):
	if event is InputEventMouseButton:
		$Viewport/GroundTiles.onMouse(event)
		
func _unhandled_input(event):
	if event is InputEventKey && event.is_pressed():
		$Viewport/GroundTiles.onKey(event)

And it worked. Hillariously, I had to use unhandled_input for keys and gui_input for mouse, and no other combination works.

I'm clearly not grokking this. Or is it that Viewports live in their own universe of events and require special plumbing like this to get away with such a design?

cybereality

You can put this on a top level script (like on the root node) and it will pass all input to the viewport.

func _input(event):
	if viewport and is_inside_tree():
		viewport.input(event)
		
func _unhandled_input(event):
	if viewport and is_inside_tree():
		viewport.unhandled_input(event)

You may need to do the same for _gui_input().

JosephAustin

@cybereality said: You can put this on a top level script (like on the root node) and it will pass all input to the viewport.
func _input(event):
	if viewport and is_inside_tree():
		viewport.input(event)
		
func _unhandled_input(event):
	if viewport and is_inside_tree():
		viewport.unhandled_input(event)
You may need to do the same for _gui_input().

Yeah that's close to what I did in my example code there. It works, I just wanted to know if there was a more elegant way.

It seems to me that a Viewport inside a Viewport Container should not be passed these events, as a modal window set to STOP should be, well, stopping them before they make their way down the tree. Also why would _unhandled_input be receiving key strokes when you're typing inside a popup, doesn't the popup 'handle' it already? It's quite confusing.

cybereality

The events pass through until they are handled. They won't be handled twice.

JosephAustin

Shouldn't it count as 'handling' them that a popup lets you type in it? It's a FileDialog. You type a filename. That doesn't count as handling the event?

JosephAustin

Either way I guess it's fine if this solution works. I just feel that a modal popup should be eating the events and not letting them propagate into a GUI-wrapped viewport.

cybereality

You can try this inside your _input() function to stop it from propagating.

get_tree().set_input_as_handled()

But I agree that something does seem odd.