(defmodule 3d-hidden
  (export all))

;;; Original example:
;;; * https://gnuplot.sourceforge.net/demo_5.2/hidden.3.gnu
(defun opts ()
 #m(title "Hidden line removal of explicit surfaces"
    style "increment default"
    view "70, 45, 1, 1"
    samples "20, 20"
    isosamples "20, 20"
    hidden3d "back offset 1 trianglepattern 3 undefined 1 altdiagonal bentover"
    style "data lines"
    xrange "[ -3.00000 : 3.00000 ] noreverse nowriteback"
    x2range "[ * : * ] noreverse writeback"
    yrange "[ -3.00000 : 3.00000 ] noreverse nowriteback"
    y2range "[ * : * ] noreverse writeback"
    zrange "[ * : * ] noreverse writeback"
    cbrange "[ * : * ] noreverse writeback"
    rrange "[ * : * ] noreverse writeback"))

(defun eqn ()
  "sin(x*x + y*y) / (x*x + y*y)")