If DefSpace is our library area, then RefSpace is the area where we place library elements as well as stand alone elements such as vias, metal traces and areas, bond fingers and wires. It also contains the netlist where each object is assigned a net property.

(RefSpace
 (Finger)
 (Package)
 (Metal)
 (Trace)
 (Wire)
 (Net)
)

Finger

A Finger represents a bondable instance of a Pad which is not associated with a package. It can be independently placed and transformed. The attach point of a wire to a ring uses a special finger. Fingers occupy only one Layer. Here is a sample finger definition.

(Finger
 (Name 'BF-1')
 (Layer 'WBT')
 (Pad 'BF100x300')
 (Net 'CLK')
 (Location -7623.0 8219.0)
 (Rotation 43.2)
 (Number '1')
 (Node
  (Wire 'W-205')
  (Trace 'T-358')
 )
)

Name

name of this finger. Must be unique.

Layer

layer on which this finger resides

Pad

name of pad that defines the finger' shape.

Net

name of net that this finger belongs to.

Location

insertion point of the finger

Rotation

rotation angle (if any) of the finger

Number

similar to name but not accessed directly by the database.

Node

a list of other objects that directly connect to this finger.