dup	duplicate top
roll	1 2 3 3 1 roll => 2 1 3 (#ops, dist to roll) put top on bottom

0 0 = lower left. 1 point = 1/72 inch

/x 4 1 add def		defines x to be 5
/x { 1 y add} def	defines a function
/z { 1 add} def
/inch {72 mul} def	Useful for going inches

moveto and lineto establish a path but don't draw a line. use stroke.

gsave grestore- these put the current graphics states on a stack

arc- x y radius start end
0 = east
Problem w/ this & linetos- I forget what this is.

arcto vertex endpoint

curveto - args?? (apparently the red book will be helpful)

text- after putting text, the point is at the end of the text
stringwidth puts the size of the string on the stack

Rotated text, transformations:
foo rotate = rotate coordinate system about origin

Put coordinate system transformations inside gsave/grestore pairs

x y scale  scales coord system
negative args OK- do flips

relative path instructions
rmoveto, rlineto, rcurveto

--end class 1