Implement UI state switching and pausing

interface/game_ui.gd

@@ -1,2 +1,21 @@
 extends VBoxContainer
 class_name GameUI
+
+## Emitted when the Score button is pressed.
+signal score_button_pressed
+
+## Emitted when the Spawn button is pressed.
+signal spawn_button_pressed 
+
+## Emitted when the Shop button is presesd.
+signal shop_button_pressed
+
+
+func _on_score_button_pressed():
+	score_button_pressed.emit()
+
+func _on_spawn_button_pressed():
+	spawn_button_pressed.emit()
+
+func _on_shop_button_pressed():
+	shop_button_pressed.emit()

interface/game_ui.tscn

@@ -45,3 +45,7 @@ layout_mode = 2
 size_flags_horizontal = 8
 text = "Shop"
 alignment = 2
+
+[connection signal="pressed" from="UpperButtons/ScoreButton" to="." method="_on_score_button_pressed"]
+[connection signal="pressed" from="UpperButtons/SpawnButton" to="." method="_on_spawn_button_pressed"]
+[connection signal="pressed" from="UpperButtons/ShopButton" to="." method="_on_shop_button_pressed"]

root.gd

@@ -1,2 +1,49 @@
 extends Node
 class_name Root
+
+
+@onready var tree: SceneTree = get_tree()
+@onready var game_ui: GameUI = $UI/GameUI
+@onready var shop_ui: ShopUI = $UI/ShopUI
+
+
+enum UIState {
+	GAME,
+	SHOP,
+	SCORE,
+}
+
+@export var ui_state: UIState:
+	get:
+		return ui_state
+	set(value):
+		match value:
+			UIState.GAME:
+				tree.paused = false
+				game_ui.show()
+				shop_ui.hide()
+			UIState.SHOP:
+				tree.paused = true
+				game_ui.hide()
+				shop_ui.show()
+			UIState.SCORE:
+				pass
+
+
+func _on_game_ui_score_button_pressed():
+	ui_state = UIState.SCORE
+
+func _on_shop_ui_back_button_pressed():
+	ui_state = UIState.GAME
+
+func _on_shop_ui_delete_button_pressed():
+	ui_state = UIState.GAME
+
+func _on_shop_ui_score_button_pressed():
+	ui_state = UIState.SCORE
+
+func _on_game_ui_shop_button_pressed():
+	ui_state = UIState.SHOP
+
+func _on_game_ui_spawn_button_pressed():
+	pass # Replace with function body.

root.tscn

@@ -1,11 +1,13 @@
-[gd_scene load_steps=5 format=3 uid="uid://cbccs6kwwf265"]
+[gd_scene load_steps=6 format=3 uid="uid://cbccs6kwwf265"]
 
+[ext_resource type="Script" path="res://root.gd" id="1_8jrhk"]
 [ext_resource type="Theme" uid="uid://ba5utvfhnxa5i" path="res://interface/interface_theme.tres" id="1_h26ax"]
 [ext_resource type="PackedScene" uid="uid://mfa1v4fsnupp" path="res://interface/game_container.tscn" id="1_xjgvu"]
 [ext_resource type="PackedScene" uid="uid://cklkdygv61bny" path="res://interface/shop_ui.tscn" id="3_lvefk"]
 [ext_resource type="PackedScene" uid="uid://bo5unrhqpoyim" path="res://interface/game_ui.tscn" id="5_2cc15"]
 
 [node name="Root" type="Node"]
+script = ExtResource("1_8jrhk")
 
 [node name="UI" type="Control" parent="."]
 texture_filter = 1
@@ -19,11 +21,20 @@ size_flags_vertical = 8
 theme = ExtResource("1_h26ax")
 
 [node name="GameContainer" parent="UI" instance=ExtResource("1_xjgvu")]
+process_mode = 1
 layout_mode = 1
 
 [node name="GameUI" parent="UI" instance=ExtResource("5_2cc15")]
+process_mode = 3
 layout_mode = 1
 
 [node name="ShopUI" parent="UI" instance=ExtResource("3_lvefk")]
-visible = false
+process_mode = 3
 layout_mode = 1
+
+[connection signal="score_button_pressed" from="UI/GameUI" to="." method="_on_game_ui_score_button_pressed"]
+[connection signal="shop_button_pressed" from="UI/GameUI" to="." method="_on_game_ui_shop_button_pressed"]
+[connection signal="spawn_button_pressed" from="UI/GameUI" to="." method="_on_game_ui_spawn_button_pressed"]
+[connection signal="back_button_pressed" from="UI/ShopUI" to="." method="_on_shop_ui_back_button_pressed"]
+[connection signal="delete_button_pressed" from="UI/ShopUI" to="." method="_on_shop_ui_delete_button_pressed"]
+[connection signal="score_button_pressed" from="UI/ShopUI" to="." method="_on_shop_ui_score_button_pressed"]