Sunburst

sunburst.py

from collections import Counter
from math import pi
import cairo

COLORS = {
    'a': (0, 0, 180),
    'b': (175, 13, 102),
    'c': (146, 248, 70),
    'd': (255, 200, 47),
    'e': (255, 118, 0),
    'f': (185, 185, 185),
    'g': (235, 235, 222),
    'h': (100, 100, 100),
    'i': (255, 255, 0),
    'j': (55, 19, 112),
    'k': (255, 255, 150),
    'l': (202, 62, 94),
    'm': (205, 145, 63),
    'n': (12, 75, 100),
    'o': (255, 0, 0),
    'p': (175, 155, 50),
    'q': (0, 0, 0),
    'r': (37, 70, 25),
    's': (121, 33, 135),
    't': (83, 140, 208),
    'u': (0, 154, 37),
    'v': (178, 220, 205),
    'w': (255, 152, 213),
    'x': (0, 0, 74),
    'y': (175, 200, 74),
    'z': (63, 25, 12),
}

def load_words(path):
    with open(path) as fp:
        data = fp.read()
    return [x.strip().lower() for x in data.split()]

def count(words):
    counter = Counter([x[0] for x in words])
    items = sorted(counter.items())
    total = float(sum(x[1] for x in items))
    return [(x[0], x[1] / total) for x in items]

def step(words, dc, cx, cy, angle1, angle2, depth):
    if depth > 1:
        return
    r1 = 512 + depth * (512 + 32)
    r2 = r1 + 512
    offset = 0
    f1 = 0.1
    f2 = 1.0 - f1
    da = angle2 - angle1
    data = count(words)
    for index, (letter, pct) in enumerate(data):
        r, g, b = COLORS[letter]
        dc.set_source_rgb(r / 255.0, g / 255.0, b / 255.0)
        s = angle1 + index * da * f1 / len(data)
        a1 = s + da * f2 * offset
        offset += pct
        a2 = s + da * f2 * offset
        dc.arc(cx, cy, r1, a1, a2)
        dc.arc_negative(cx, cy, r2, a2, a1)
        dc.close_path()
        dc.fill()
        new_words = filter(None, [x[1:] for x in words if x[0] == letter])
        step(new_words, dc, cx, cy, a1, a2, depth + 1)

def render(path):
    words = load_words('TWL06.txt')
    width = height = 4096
    cx = cy = width / 2
    surface = cairo.ImageSurface(cairo.FORMAT_RGB24, width, height)
    dc = cairo.Context(surface)
    dc.set_source_rgb(1, 1, 1)
    dc.paint()
    dc.set_source_rgb(0, 0, 0)
    dc.set_line_width(1)
    step(words, dc, cx, cy, -pi / 2, 2 * pi - pi / 2, 0)
    # dc.stroke()
    surface.write_to_png(path)

def main():
    render('output.png')

if __name__ == '__main__':
    main()