Split MaterialGroup and MaterialNode

cura/Machines/MaterialNode.py

@@ -0,0 +1,21 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+
+from typing import Optional
+
+from .ContainerNode import ContainerNode
+
+
+#
+# A MaterialNode is a node in the material lookup tree/map/table. It contains 2 (extra) fields:
+#  - material_map: a one-to-one map of "material_root_id" to material_node.
+#  - children_map: the key-value map for child nodes of this node. This is used in a lookup tree.
+#
+#
+class MaterialNode(ContainerNode):
+    __slots__ = ("material_map", "children_map")
+
+    def __init__(self, metadata: Optional[dict] = None):
+        super().__init__(metadata = metadata)
+        self.material_map = {}  # material_root_id -> material_node
+        self.children_map = {}  # mapping for the child nodes