Implemented group highlight on hover

It's not currently stable, but it's ok for now.

grid.gd

@@ -1,4 +1,5 @@
 extends Node2D
+class_name Grid
 
 @export var rows: int = 5
 @export var cols: int = 5
@@ -8,6 +9,7 @@ extends Node2D
 
 var grid: Array[Array]
 var groups: Array
+var hovered_group: Array
 
 var debug_label: Label
 
@@ -25,6 +27,7 @@ func _ready():
 			token_node.set_type(randi_range(0,3) as Token.token_type)
 			token_node.set_debug_label(str(row) + "," + str(column))
 			token_node.token_clicked.connect(_on_token_clicked.bind([row,column]))
+			token_node.token_hovered.connect(_on_token_hovered.bind([row,column]))
 			grid[row].append(token_node)
 
 	calculate_token_groups()
@@ -42,8 +45,25 @@ func _on_token_clicked(token_coord):
 
 		update_grid()
 
-func highlight_group(group: Array):
-	pass
+func _on_token_hovered(enter: bool, coord: Array):
+	var group = get_group_of_token(coord)
+	if enter:
+		highlight_group(group, true)
+	else:
+		highlight_group(group, false)
+
+func highlight_group(group: Array, enable: bool):
+	if group != hovered_group:
+#		Un-highlight current, update current
+		for coord in hovered_group:
+			var current_token = grid[coord[0]][coord[1]]
+			current_token.set_highlighted(false)
+
+	for coord in group:
+		var current_token = grid[coord[0]][coord[1]] as Token
+		current_token.set_highlighted(enable)
+
+	hovered_group = group
 
 func update_grid():
 	pass

token.gd

@@ -2,6 +2,7 @@ extends Node2D
 class_name Token
 
 signal token_clicked
+signal token_hovered(entered: bool)
 
 enum token_type {TYPE_1, TYPE_2, TYPE_3, TYPE_4}
 enum token_state {NONE, HIGHLIGHT}
@@ -41,3 +42,15 @@ func _on_area_2d_input_event(viewport: Node, event: InputEvent, shape_idx: int)
 
 func set_highlighted(highlight: bool):
 	state = token_state.HIGHLIGHT if highlight else token_state.NONE
+	match state:
+		token_state.HIGHLIGHT:
+			highlight_polygon.visible = true
+		token_state.NONE:
+			highlight_polygon.visible = false
+
+
+func _on_area_2d_mouse_entered() -> void:
+	token_hovered.emit(true)
+
+func _on_area_2d_mouse_exited() -> void:
+	token_hovered.emit(false)

token.tscn

@@ -43,9 +43,12 @@ color = Color(0.84101, 0.000705212, 0.866408, 1)
 polygon = PackedVector2Array(0, 0, 40, 0, 40, 40, 0, 40)
 
 [node name="highlight_indicator" type="Polygon2D" parent="."]
+visible = false
 position = Vector2(52.8333, 76.6667)
 scale = Vector2(0.427083, 0.319444)
 polygon = PackedVector2Array(-112, -96, -16, -96, -64, -168)
 uv = PackedVector2Array(-112, -96, -16, -96, -72, -160)
 
 [connection signal="input_event" from="Area2D" to="." method="_on_area_2d_input_event"]
+[connection signal="mouse_entered" from="Area2D" to="." method="_on_area_2d_mouse_entered"]
+[connection signal="mouse_exited" from="Area2D" to="." method="_on_area_2d_mouse_exited"]