color-field as an addition to the plot renderers. (mandelbrot taken from rosettacode)
The bees are holding a day-time rave?
Looks like it!
Passionflower in Bristol
Actually, thinking about it, bees do perform dances to communicate…
You can achieve a similar result using the contour-intervals render, although the parameters are different:
#lang racket
(require plot plot/utils)
(define (iterations a z i)
(define zp (+ (* z z) a))
(if (or (<= 255 i) (< 2 (magnitude zp)))
i
(iterations a zp (+ i 1))))
(define (mandelbrot x y)
(define z (make-rectangular (* 1.0 x) (* 1.0 y)))
(iterations z 0 0))
(plot (contour-intervals mandelbrot -2.25 0.75 -1.25 1.25
#:levels 255 #:samples 200))
Although it would be nice to have a heat map type render where the rendered receives a 2d float array and renders it as a heat map, using color levels.