Munching Squares N. A Display Hack Dating Back To The PDP-1 (ca.

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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 variab