There are eleven types of geometric primitive element corresponding to the shapes shown in Figure 17:3.: Drafting Primitives.

As a primitive element is created, its position is stored separately, with a reference to the position being stored as the primitive’s PTRF (or PTFA) attribute. An important feature of this system is that if a series of primitives is created, each primitive’s position reference (or drafting point) will (initially) be the same, enabling a series of ‘connected’ shapes to be quickly and easily created. For example, the command sequence

would create a series of concentric circles. In a similar way, a series of connected straight lines could be created. (A line may have two position references, one at either end; the start position reference of one line would be set equal to the end position reference of the previous line. Refer to Creating and Manipulating Drafting Primitives - Common Operations for further information.) A set of primitives connected in this way may be moved as a ‘group’ by using the DRAG command.

DRAW offers you a variety of methods of defining, identifying, sizing, positioning, orienting, moving and querying drafting primitives. Many methods of carrying out these operations are common to all (or most) of the drafting primitives. These methods are described in the next section; methods that apply to particular primitives (and to Symbols) are described in Creating and Manipulating Drafting Primitives - Common Operations.