/
fractal.go
74 lines (60 loc) · 1.26 KB
/
fractal.go
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package main
import (
"flag"
"image"
"image/color"
"image/png"
"os"
)
var (
centerx = flag.Float64("centerx", 0, "X component of center")
centery = flag.Float64("centery", 0, "y component of center")
width = flag.Float64("width", 4, "viewport width")
height = flag.Float64("height", 4, "viewport height")
)
type cn struct {
i float64
r float64
}
func main() {
flag.Parse()
im := image.NewGray(image.Rectangle{image.Point{0, 0}, image.Point{1000, 1000}})
GenerateFractal(im)
f, err := os.Create("./output.png")
defer f.Close()
if err != nil {
println(err)
}
png.Encode(f, im)
}
func square(x float64) float64 {
return x * x
}
func GenerateFractal(im *image.Gray) {
z := &cn{}
c := &cn{}
g := color.Gray{}
for x := 0; x < 1000; x++ {
for y := 0; y < 1000; y++ {
c.r = (*width * float64(x) / float64(1000)) - *width/float64(2)
c.i = (*height * float64(y) / float64(1000)) - *height/float64(2)
c.r += *centerx
c.i += *centery
z.r = 0
z.i = 0
zrsqr := z.r * z.r
zisqr := z.i * z.i
var i uint8 = 0
for zrsqr+zisqr < 4.0 && i < 255 {
i++
z.i = square(z.r+z.i) - zrsqr - zisqr
z.i += c.i
z.r = zrsqr - zisqr + c.r
zrsqr = square(z.r)
zisqr = square(z.i)
}
g.Y = i
im.SetGray(x, y, g)
}
}
}