Defines the SDM model and the graph model.
There are two key concepts: the graph
model and the SDM model of the
diagram component (subclass of IlvDiagrammer). It is important to avoid
confusion between them.
The SDM model
The SDM model represents the application
objects. Application objects typically have only logical
properties, not graphic properties (position, size, shape, and
so on). The rendering process produces graphic objects for the
SDM model objects.
The graph model
The graph model of the layout algorithms
is an abstraction of the graphic properties of these graphic
objects., not an abstraction of the application objects.