munching squares

munching squares
 n.

   A {display hack} dating back to the PDP-1 (ca. 1962, reportedly
   discovered by Jackson Wright), which employs a trivial computation
   (repeatedly plotting the graph Y = X XOR T for successive values of T
   -- see {HAKMEM} items 146--148) to produce an impressive display of
   moving and growing squares that devour the screen. The initial value
   of T is treated as a parameter, which, when well-chosen, can produce
   amazing effects. Some of these, later (re)discovered on the LISP
   machine, have been christened munching triangles (try AND for XOR and
   toggling points instead of plotting them), munching w's, and munching
   mazes. More generally, suppose a graphics program produces an
   impressive and ever-changing display of some basic form, foo, on a
   display terminal, and does it using a relatively simple program; then
   the program (or the resulting display) is likely to be referred to as
   munching foos. [This is a good example of the use of the word {foo} as
   a {metasyntactic variable}.]
    

munching squares

   A {display hack} dating back to the {PDP-1} (ca. 1962,
   reportedly discovered by Jackson Wright), which employs a
   trivial computation (repeatedly plotting the graph Y = X XOR T
   for successive values of T - see {HAKMEM} items 146--148) to
   produce an impressive display of moving and growing squares
   that devour the screen.  The initial value of T is treated as
   a parameter, which, when well-chosen, can produce amazing
   effects.  Some of these, later (re)discovered on the {LISP
   Machine}, have been christened "munching triangles" (try AND
   for XOR and toggling points instead of plotting them),
   "munching w's", and "munching mazes".  More generally, suppose
   a graphics program produces an impressive and ever-changing
   display of some basic form, foo, on a display terminal, and
   does it using a relatively simple program; then the program
   (or the resulting display) is likely to be referred to as
   "munching foos".  [This is a good example of the use of the
   word {foo} as a {metasyntactic variable}.]