You can define custom vectors to use as rendering normals using the NodeUserNormal attribute. This is an alternative to creating a user normal property and then using ICE to set Self.cls.User_Normal_Cluster.User_Normal_Property.Normals. The advantage of NodeUserNormal is that you do not require a cluster and user normal property.
Calculate the normal values that you want to use and set NodeUserNormal. Once this attribute has been set, its values will be used for rendering and display in the viewports instead of the automatic normals. However, it does not work with subdivision surfaces created by a geometry approximation property.
In place of other cluster properties like weight maps and vertex colors, you can use the Attribute and Map Lookup shaders with any ICE attribute on a polygon mesh. You do not need to create clusters and properties first.
Note that if you are using a custom ICE attribute instead of a weight map or vertex color property, you cannot paint on it interactively or edit its values. To change values manually, you must first apply a non-ICE weight map or vertex color property and set its values with the ICE attribute. After that, any modifications you make manually are applied on top of the values set by ICE.
However, you can display custom color attributes on polynodes in the viewports by choosing the attribute in the Vertex Color Display Property option on the OpenGL Display tab of the Material Node Property Editor.
