diff --git a/addons/material_maker/engine/gen_graph.gd b/addons/material_maker/engine/gen_graph.gd
index 8fb9859..e036c5f 100644
--- a/addons/material_maker/engine/gen_graph.gd
+++ b/addons/material_maker/engine/gen_graph.gd
@@ -105,3 +105,6 @@ func _serialize(data):
 		data.nodes.append(c.serialize())
 	data.connections = connections
 	return data
+
+func edit(node):
+	node.get_parent().call_deferred("update_view", self)
\ No newline at end of file
diff --git a/addons/material_maker/engine/gen_shader.gd b/addons/material_maker/engine/gen_shader.gd
index 4fe0902..a50a2d4 100644
--- a/addons/material_maker/engine/gen_shader.gd
+++ b/addons/material_maker/engine/gen_shader.gd
@@ -213,3 +213,11 @@ func get_globals():
 func _serialize(data):
 	data.shader_model = shader_model
 	return data
+
+func edit(node):
+	if shader_model != null:
+		var edit_window = load("res://addons/material_maker/widgets/node_editor/node_editor.tscn").instance()
+		node.get_parent().add_child(edit_window)
+		edit_window.set_model_data(shader_model)
+		edit_window.connect("node_changed", node, "update_generator")
+		edit_window.popup_centered()
diff --git a/addons/material_maker/graph_edit.gd b/addons/material_maker/graph_edit.gd
index 89b2cc8..72d93c1 100644
--- a/addons/material_maker/graph_edit.gd
+++ b/addons/material_maker/graph_edit.gd
@@ -8,6 +8,7 @@ var renderer = null
 var save_path = null setget set_save_path
 var need_save = false
 
+var top_generator = null
 var generator = null
 
 signal save_path_changed
@@ -86,15 +87,24 @@ func set_save_path(path):
 		update_tab_title()
 		emit_signal("save_path_changed", self, path)
 
-func clear_material():
+func clear_view():
 	clear_connections()
 	for c in get_children():
 		if c is GraphNode:
 			remove_child(c)
 			c.free()
-	if generator != null:
-		remove_child(generator)
-		generator.free()
+
+func update_view(g):
+	clear_view()
+	generator = g
+	update_graph(generator.get_children(), generator.connections)
+	$ButtonUp.visible = generator != top_generator
+
+func clear_material():
+	if top_generator != null:
+		remove_child(top_generator)
+		top_generator.free()
+		top_generator = null
 		generator = null
 	send_changed_signal()
 
@@ -115,10 +125,10 @@ func update_graph(generators, connections):
 func new_material():
 	clear_material()
 	var loader = MMGenLoader.new()
-	generator = loader.create_gen({nodes=[{name="Material", type="material"}], connections=[]})
-	if generator != null:
-		add_child(generator)
-		update_graph(generator.get_children(), generator.connections)
+	top_generator = loader.create_gen({nodes=[{name="Material", type="material"}], connections=[]})
+	if top_generator != null:
+		add_child(top_generator)
+		update_view(top_generator)
 		set_save_path(null)
 		set_need_save(false)
 		center_view()
@@ -145,16 +155,16 @@ func create_nodes(data, position : Vector2 = Vector2(0, 0)):
 
 func load_file(filename):
 	clear_material()
-	generator = MMGenLoader.load_gen(filename)
-	if generator != null:
-		add_child(generator)
-		update_graph(generator.get_children(), generator.connections)
+	top_generator = MMGenLoader.load_gen(filename)
+	if top_generator != null:
+		add_child(top_generator)
+		update_view(top_generator)
 		set_save_path(filename)
 		set_need_save(false)
 		center_view()
 
 func save_file(filename):
-	var data = generator.serialize()
+	var data = top_generator.serialize()
 	var file = File.new()
 	if file.open(filename, File.WRITE) == OK:
 		file.store_string(to_json(data))
@@ -258,3 +268,7 @@ func drop_data(position, data):
 		Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)
 	create_nodes(data, offset_from_global_position(get_global_transform().xform(position)))
 	return true
+
+func on_ButtonUp_pressed():
+	if generator != top_generator && generator.get_parent() is MMGenGraph:
+		call_deferred("update_view", generator.get_parent())
diff --git a/addons/material_maker/graph_edit.tscn b/addons/material_maker/graph_edit.tscn
index 2b611c3..ad08ee3 100644
--- a/addons/material_maker/graph_edit.tscn
+++ b/addons/material_maker/graph_edit.tscn
@@ -13,6 +13,16 @@ script = ExtResource( 1 )
 [node name="Timer" type="Timer" parent="."]
 wait_time = 0.2
 one_shot = true
+
+[node name="ButtonUp" type="Button" parent="."]
+anchor_left = 1.0
+anchor_right = 1.0
+margin_left = -44.0
+margin_top = 4.0
+margin_right = -14.0
+margin_bottom = 24.0
+text = "Up"
 [connection signal="connection_request" from="." to="." method="connect_node"]
 [connection signal="disconnection_request" from="." to="." method="disconnect_node"]
 [connection signal="timeout" from="Timer" to="." method="do_send_changed_signal"]
+[connection signal="pressed" from="ButtonUp" to="." method="on_ButtonUp_pressed"]
diff --git a/addons/material_maker/nodes/generic.gd b/addons/material_maker/nodes/generic.gd
index fc83735..c16c2b9 100644
--- a/addons/material_maker/nodes/generic.gd
+++ b/addons/material_maker/nodes/generic.gd
@@ -206,12 +206,8 @@ func update_node():
 		edit_buttons.connect_buttons(self, "edit_generator", "load_generator", "save_generator")
 
 func edit_generator():
-	var edit_window = load("res://addons/material_maker/widgets/node_editor/node_editor.tscn").instance()
-	get_parent().add_child(edit_window)
-	if generator.shader_model != null:
-		edit_window.set_model_data(generator.shader_model)
-	edit_window.connect("node_changed", self, "update_generator")
-	edit_window.popup_centered()
+	if generator.has_method("edit"):
+		generator.edit(self)
 
 func update_generator(shader_model):
 	generator.set_shader_model(shader_model)