feat: complete mobile UI implementation

project/ui/mouse_controller.gd

@@ -14,6 +14,8 @@ var _icon: TextureRect
 var _label: Label
 var _attached: Dictionary = {}
 var _targets: Array[Dictionary] = []
+var _touch_index := -1
+var _touch_position := Vector2.ZERO
 
 func setup(parent: Node, cursor_manager: Node = null, audio_node: Node = null) -> void:
 	cursor = cursor_manager
@@ -41,11 +43,15 @@ func setup(parent: Node, cursor_manager: Node = null, audio_node: Node = null) -
 	set_process_input(true)
 
 func attach_item(window: int, cell: int, vnum: int, count: int,
-		texture: Texture2D = null, source := "inventory", metadata: Dictionary = {}) -> bool:
+		texture: Texture2D = null, source := "inventory", metadata: Dictionary = {},
+		touch_index := -1, touch_position := Vector2(-1, -1)) -> bool:
 	if vnum <= 0 or window < 0 or cell < 0:
 		return false
 	_attached = {"window": window, "cell": cell, "vnum": vnum,
 			"count": maxi(1, count), "source": source}
+	_touch_index = touch_index
+	if touch_position.x >= 0.0 and touch_position.y >= 0.0:
+		_touch_position = touch_position
 	# Keep the instance fields that the reference mouse module exposes to the
 	# receiving window (anti flags, sockets, attributes, ...), while retaining
 	# the canonical source coordinates supplied by the caller.
@@ -70,6 +76,8 @@ func attach_money(amount: int, source := "inventory") -> bool:
 		return false
 	_attached = {"window": -1, "cell": -1, "vnum": -1, "count": amount,
 			"source": source, "money": true}
+	_touch_index = -1
+	_touch_position = Vector2.ZERO
 	if _icon:
 		_icon.texture = null
 		_icon.visible = false
@@ -85,6 +93,8 @@ func attach_money(amount: int, source := "inventory") -> bool:
 
 func cancel() -> void:
 	_attached.clear()
+	_touch_index = -1
+	_touch_position = Vector2.ZERO
 	if _overlay:
 		_overlay.visible = false
 	if cursor and cursor.has_method("reset"):
@@ -108,7 +118,10 @@ func unregister_owner(owner: Node) -> void:
 
 func _process(_dt: float) -> void:
 	if _overlay and _overlay.visible:
-		_overlay.global_position = get_viewport().get_mouse_position() + Vector2(12, 12)
+		var position := get_viewport().get_mouse_position()
+		if _touch_index >= 0:
+			position = _touch_position
+		_overlay.global_position = position + Vector2(12, 12)
 	# 清理已被窗口销毁的目标，防止拖放回调落到旧 UI。
 	for i in range(_targets.size() - 1, -1, -1):
 		var c: Control = _targets[i].get("control", null)
@@ -129,6 +142,15 @@ func _input(event: InputEvent) -> void:
 	if event is InputEventMouseButton and not event.pressed and event.button_index == MOUSE_BUTTON_LEFT:
 		_drop_at(event.position)
 		get_viewport().set_input_as_handled()
+		return
+	if event is InputEventScreenDrag and event.index == _touch_index:
+		_touch_position = event.position
+		get_viewport().set_input_as_handled()
+		return
+	if event is InputEventScreenTouch and not event.pressed and event.index == _touch_index:
+		_touch_position = event.position
+		_drop_at(event.position)
+		get_viewport().set_input_as_handled()
 
 func _drop_at(position: Vector2) -> void:
 	var payload := attached()