> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/sidef-lang/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/sidef-lang/programming_tasks/f/fractal_tree.md).

# Fractal tree

```ruby
func tree(img, x, y, scale=6/10, len=400, angle=270) {

    len < 1 && return()

    img.moveTo(x, y)
    img.angle(angle)
    img.line(len)

    var (x1, y1) = img.curPos
    tree(img, x1, y1, scale, len*scale, angle+35)
    tree(img, x1, y1, scale, len*scale, angle-35)
}

require('GD::Simple')

var (width=1000, height=1000)
var img = %s<GD::Simple>.new(width, height)
img.fgcolor('black')
img.penSize(1, 1)

tree(img, width/2, height)

File('tree.png').write(img.png, :raw)
```