Extremely brief summary of format of .def files:

| anything... <newline>

	comment.  everything through next newline ignored.

d name

	define, "name" is name of object which most programs ignore, taking
	the name of the object from the name of the file instead.

e

	end of file.

m x y

	move current position to x,y.

l x y

	line from current point to specified coordinate.  Updates
	current position.

A x y arc

	arc from current point to specified coordinate.  "arc" specifies
	how big arc should be -- 2048 units in a full circle.  For example,
	if arc=1024, a semicircle is drawn starting from the current
	coord and proceeding clockwise to specified coordinate.  Current
	position is updated.

c orient label

	character label.  orient is one of {c, t, b} x {c, l, r} where
	c=center, t=top, b=bottom, l=left, r=right.  Orient specifies where
	the current position lies with respect to label.  Label is a
	character string (no surrounding quotes!) with spaces replaced by
	"~" chars.


i name scale orient

	instatiate subpicture.  "name" is name of subpicture which should be
	found in file name.def.  scale is a pair of integers separated by
	colon (eg, 2:1), all coords of subpicture are multiplied first number
	and then divided by the second (so 2:1 will double the size of the
	subpicture).  orient specifies one of n, e, s, w, rn, re, rs, rw
	where r indicates reversal about y axis before specified rotation.