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ps.pl

# Description: This set of routines is used to build a PostScript graph that
#              represents the conditional branching of C code.  For the most
#              part, the individual routines are self-explanatory, but a
#              couple of concepts concerning the PostScript code aren't
#              immediately evident.
#              
#              The PostScript subroutines treat the drawing space as though
#              it were tiled into squares.  All symbol drawing is done in
#              proportion to the size of the squares.
#              
#              Scaling of the graph is achieved by scaling the coordinate
#              axes.  This means that everything gets drawn bigger or smaller,
#              depending on the scale factor.  Line width even varies.
#              
#              The PostScript code that these routines has been tested and
#              appears to work on level 1 and level 2 devices.  However,
#              for larger files, interpreter stack overflow seems to be a 
#              problem.  So far, a level 2 printer has never failed to print
#              the graph, but level 1 printers and GhostView start having 
#              problems with the larger files.  How large is large?  I don't
#              know exactly.  It also depends on the printer and which version
#              of GhostScript is being used.