おせえよ

mand.go

package main

import (
	"math/cmplx"
	"image"
	"image/color"
	"image/png"
	"os"
)

func mand (c complex128, max_iter uint8) (bool, uint8) {
	z := 0 + 0i
	z1 := 0 + 0i
	var n uint8 = 0
	for ; n < max_iter; n++ {
		z1 = cmplx.Pow(z, 2) + c
		if cmplx.Abs(z) > 2 {
			return true, n
		}
		z = z1
	}
	return false, n;
}

func main() {

	width := 640
	height := 640

	img := image.NewRGBA(image.Rect(0, 0, width, height))

	for imy := 0; imy < height; imy++ {
		for imx := 0; imx < width; imx++ {

			vx := float64(imx - width  / 2) / float64(width / 2) * 2.0
			vy := float64(imy - height / 2) / float64(height / 2) * 2.0
			c := complex(vx, vy)

			divergence, speed := mand(c, 0xFF);

			if (!divergence) {
				img.Set(imx, imy, color.RGBA{0, 0, 0, 0xFF})
			} else {
				img.Set(imx, imy, color.RGBA{speed, speed, speed, 0xFF})
			}

		}
	}

	f, _ := os.Create("out.png")
	defer f.Close()
	png.Encode(f, img)

}