Curve Objects	Developer's Guide	The Undo Mechanism

The Document and Graphics Classes

The document is represented by a tree of graphics objects. The document consists of one or more layers. Each layer consists of zero or more primitives or compound objects.

Primitives are the leaves of the tree and contain no other graphics objects, examples are Rectangles or PolyBezier objects. Most primitives can have line and fill properties (Text objects currently can only have fill properties and image objects have neither fill nor line properties).

Compound objects are graphics objects that contain other graphics objects, examples are the ordinary Group or the BlendGroup.

Class Hierarchy

The class GraphicsObject

The class Bounded

The class HierarchyNode

The class Protocols

The class Selectable

The class Primitive

The class Compound

The class Rectangle

Curve Objects	Developer's Guide	The Undo Mechanism