Variable: artist-octant-info

artist-octant-info is a variable defined in artist.el.gz.

Value

[[2 1 1 0 1 1] [1 2 1 1 0 1] [-1 2 0 1 -1 1] [-2 1 -1 1 -1 0]
 [-2 -1 -1 0 -1 -1] [-1 -2 -1 -1 0 -1] [1 -2 0 -1 1 -1]
 [2 -1 1 -1 1 0]]

Documentation

Table used by line drawing algorithm (eight point).

Source Code

;; Defined in /usr/src/emacs/lisp/textmodes/artist.el.gz
;; Things for drawing lines in all directions.
;; The line drawing engine is the eight-point algorithm.
;;
;; A line is here a list of (x y saved-char new-char)s.
;;
(defvar artist-octant-info
  ;; Initial	Step in		Step in
  ;; coeffs	x and y		x and y
  ;; for	if q >= 0	if g < 0
  ;; dfdx,dfdy
  [ [  2  1	 1  0		 1  1 ]		; 1st octant
    [  1  2	 1  1		 0  1 ]		; 2nd octant
    [ -1  2	 0  1		-1  1 ]		; 3rd octant
    [ -2  1	-1  1		-1  0 ]		; 4th octant
    [ -2 -1	-1  0		-1 -1 ]		; 5th octant
    [ -1 -2	-1 -1		 0 -1 ]		; 6th octant
    [  1 -2	 0 -1		 1 -1 ]		; 7th octant
    [  2 -1	 1 -1		 1  0 ] ]	; 8th octant
  "Table used by line drawing algorithm (eight point).")