shithub: mc

ref: 0173ca92374d915bd5c9b40c307f368e1cadbaf4
dir: /test/mandelbrot.myr/

use std
use bio

const Bailout : flt64 = 16.0
const Maxiter = 1000

const mandelbrot = {x, y
	var cr, ci, zr, zi
	var tmp, zr2, zi2
	var i : int

	cr = y - 0.5
	ci = x
	zr = 0.0
	zi = 0.0

	i = 0

	while true
		i++
		tmp  = zr * zi
		zr2 = zr * zr
		zi2 = zi * zi
		zr = zr2 - zi2 + cr
		zi = tmp + tmp + ci
		if zi2 + zr2 > Bailout
			-> i
		;;
		if i > Maxiter
			-> 0
		;;
	;;
}

const main = {args : byte[:][:]
	var x : flt64, y : flt64, i
	var f

	f = bio.mkfile(1, bio.Wr)
	for y = -39.0; y < 39.0; y = y + 1.0
		for x = -39.0; x < 39.0; x = x + 1.0
			i = mandelbrot(x/40.0, y/40.0)
			if i == 0
				bio.write(f, "*")
			else
				bio.write(f, " ")
			;;
		;;
		bio.write(f, "\n")
	;;
	bio.write(f, "\n")
	bio.close(f)
}