Capturing the Mouse

Problem

You want to hide the mouse cursor and keep the mouse from leaving the game window. This is common in many 3D games (and some 2D ones).

Solution

You can set the mouse state using Input.set_mouse_mode(). There are four possible mouse modes:

  • MOUSE_MODE_VISIBLE: The mouse is visible and can move freely into and out of the window. This is the default state.

  • MOUSE_MODE_HIDDEN: The mouse cursor is invisible, but the mouse can still move outside the window.

  • MOUSE_MODE_CAPTURED: The mouse cursor is hidden and the mouse is unable to leave the game window.

  • MOUSE_MODE_CONFINED: The mouse is visible, but cannot leave the game window.

“Captured” is the most commonly used option. You can set the mouse mode at runtime using:

func _ready():
    Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)

When the mouse is captured, mouse input events will still be passed as normal. However, you will find there is a problem. If you want to close the game or switch to another window, you can’t. For this reason, you will want to also include a way to “release” the mouse. For example, to release when the player pressed the Escape key:

func _input(event):
    if event.is_action_pressed("ui_cancel"):
        Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)

So that the game doesn’t respond to mouse movement when you’re in another window, you can test for the capture state in your character controller using:

if Input.get_mouse_mode() == Input.MOUSE_MODE_CAPTURED:

Once the mouse is released, that leaves the need to re-capture it to continue playing. Assuming you have an event in the Input Map for a mouse click, you can do the following:

    if event.is_action_pressed("click"):
        if Input.get_mouse_mode() == Input.MOUSE_MODE_VISIBLE:
            Input.set_mouse_mode(Input.MOUSE_MODE_CAPTURED)

Since you may also be using a mouse click to shoot or perform some other action, it’s probably a good idea to stop the event from propagating. Add this after setting the mouse mode:

get_tree().set_input_as_handled()

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