Plot a dict of Lat, Lon points in an image. Requires the PIL.

latlong.py

# Courtesy of Charlie Loyd (@vruba), it's a black box for now
# Expects a dict of points, 'points' with keys 'Lat.', and 'Lon.'
from PIL import Image
from math import *

# these are London-specific
latrange = [51, 52]
lonrange = [-1, 1]


latgrain = 1 / 400.0
longrain = latgrain / cos(radians((latrange[0] + latrange[1]) / 2.0))


def K(h, amt):
    r = sin(pi*h)
    g = sin(pi*(h + 1.0 / 3.0))
    b = sin(pi*(h + 2.0 / 3.0))
    return tuple(int(amt*ch*ch) for ch in (r, g, b))


def bump(a, b):
    return tuple(map(lambda x, y: x + y, a, b))


def color(lang, amt):
    lang = lang.strip()
    if lang == 'pt':
        return (amt, 0, 0)
    if lang == 'en':
        return (0, amt, 0)
    else:
        return (0, 0, amt)


def scalelat(lat):
    return (lat-latrange[0]) * 1 / latgrain


def scalelon(lon):
    return (lon-lonrange[0]) * 1 / longrain


width = int(round((lonrange[1] - lonrange[0]) * 1 / longrain)) + 1
height = int(round((latrange[1] - latrange[0]) * 1 / latgrain)) + 1

print 'height: ' + str(latgrain * height * 111.2) + ' km'
print 'width: ' + str(longrain * latgrain/longrain * width * 111.2) + ' km'

i = Image.new('RGB', (width, height))
p = i.load()

for point in points:
    y = int(scalelat(float(point['Lat.'])))
    x = int(scalelon(float(point['Lon.'])))
    y = height-y
    c = (2, 2, 2)
    try:
        p[x, y] = bump(p[x, y], c)
    except:
        print("Argh!")
        raise()

i.save("map.png")