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The point Stanza

As with the component stanzas, there is exactly one point stanza for each wire point on the workarea canvas. Each point stanza has four attributes; namely, id, coords, adjcnt and net.

The id attribute represents the unique numeric identifier of the point on the workarea canvas. It serves as a means by which the point can be referenced by other stanzas in the circuit description. The coords attribute, like the coords attribute of the component stanza, stores the coordinates of the wire point on the canvas. These coordinates are obtained from the pnt_coord global array of the GUI implementation. The adjcnt attribute stores the identifiers of all the points that are adjacent to the point. The final attribute, net, stores the identifier of the netlist to which the point belonged when the circuit was saved. This value is stored in the circuit file so that netlist extraction does not have to take place when the circuit is restored by the user. Note that there is no need to store the identifiers of wires in the circuit file since each of the wires can be reconstructed from the adjacency lists of each point. An example of a point stanza is presented in Figure B.2.

Figure B.2: Example of a point Stanza

Donald Craig
Mon Jul 8 12:05:35 NDT 1996