Limit Camera Movement

Help Programming
, ,
1

Godot Version

4.3

Question

I have a 2D Scene with multiple TileMapLayers, and have created a script to allow the user to drag the Camera2D whilst holding the right mouse button:

extends Camera2D

var dragging = false
var last_mouse_position = Vector2()

func _input(event):
	if event is InputEventMouseButton:
		if event.button_index == MOUSE_BUTTON_RIGHT:
			dragging = event.pressed
			if dragging:
				last_mouse_position = event.position
				
	elif event is InputEventMouseMotion and dragging:
		var delta = event.position - last_mouse_position
		position -= delta
		last_mouse_position = event.position

I want to limit the movement of the camera so it doesn’t move past any edge of the base TileMapLayer so the TileMapLayers are always in view of the camera, but I am struggling to figure out how to work this. What would be a good way to achieve this?

Thanks in advance

2

The camera2d has a limit-property for every direction. This should do the trick

1 Like
3

Thank you.

I’ve been playing with this, and I am able to get it to work for the top and left, but the right hand side and bottom are off:

extends Camera2D

var dragging = false
var last_mouse_position = Vector2()

@export var limitTileMapLayer: TileMapLayer

func _ready() -> void:
	if limitTileMapLayer:
		var map_rect = limitTileMapLayer.get_used_rect()
		var map_size = Vector2(map_rect.size) * limitTileMapLayer.cell_size
		
		limit_left = map_rect.position.x * limitTileMapLayer.cell_size.x
		limit_top = map_rect.position.y * limitTileMapLayer.cell_size.y
		
		var window_size = DisplayServer.window_get_size()
		limit_right = (limit_left + map_size.x) - window_size.x / zoom.x
		limit_bottom = limit_top + map_size.y - window_size.y / zoom.y
	else:
		print("TileMapLayer not assigned")

func _input(event):
	if event is InputEventMouseButton:
		if event.button_index == MOUSE_BUTTON_RIGHT:
			dragging = event.pressed
			if dragging:
				last_mouse_position = event.position
				
	elif event is InputEventMouseMotion and dragging:
		var delta = event.position - last_mouse_position
		position -= delta
		last_mouse_position = event.position
		_clamp_position()

func _clamp_position():
	position.x = clamp(position.x, limit_left, limit_right)
	position.y = clamp(position.y, limit_top, limit_bottom)
4

how far off?

5

Approximately half the window width. When it finishes, the right edge of the map is approximately in the centre of the camera

6

then just apply this offset to the limit