DiagramObject: An object that defines one or more points in a given space.
DiagramObjectGluePoint: This is used for grouping diagram object points from different diagram objects that are considered to be glued together in a diagram even if they are not at the exact same coordinates.
DiagramObjectPoint: A point in a given space defined by 3 coordinates and associated to a diagram object.
DiagramObjectStyle: A reference to a style used by the originating system for a diagram object.
DiagramStyle: The diagram style refers to a style used by the originating system for a diagram.
IdentifiedObject: This is a root class to provide common identification for all classes needing identification and naming attributes.
TextDiagramObject: A diagram object for placing free-text or text derived from an associated domain object.
VisibilityLayer: Layers are typically used for grouping diagram objects according to themes and scales.