render.py

#!/usr/bin/python

from __future__ import print_function
from datetime import datetime, timedelta
from heightmap import HeightMap
from suncalc import solar_position
from shadowmap import ShadowMap, get_projection_north_deviation
from math import sin, cos
from os import path
from PIL import Image, ImageChops, ImageDraw
import argparse

parser = argparse.ArgumentParser()
parser.add_argument('heightmap', type=str, help='Path to heightmap file')
parser.add_argument('start', type=str, help='Start date and time (YYYY-MM-DD HH:MM)')
parser.add_argument('end', type=str, help='End date and time (YYYY-MM-DD HH:MM)')
parser.add_argument('interval', type=int, help='Interval between images in minutes')
parser.add_argument('output_directory', type=str, help='Path to store images in')
parser.add_argument('--background-map', type=str, default=None, help='Path to background map image')
parser.add_argument('--opacity', type=float, default=1, help='Opacity for shadow when overlaid (0-1)')

args = parser.parse_args()

with open(args.heightmap, 'rb') as f:
    hm = HeightMap.load(f)

t1 = datetime.strptime(args.start, '%Y-%m-%d %H:%M')
t2 = datetime.strptime(args.end, '%Y-%m-%d %H:%M')
delta = timedelta(minutes=args.interval)

bkg = None
if args.background_map:
    bkg = Image.open(args.background_map).convert('RGB')
    transparency = int(255 - args.opacity * 255)

t = t1
while t <= t2:
    print(t.strftime('%Y-%m-%d_%H%M.png'), '...')
    sunpos = solar_position(t, hm.lat, hm.lng)
    dev = get_projection_north_deviation(hm.proj, hm.lat, hm.lng)
    sun_x = -sin(sunpos['azimuth'] - dev) * cos(sunpos['altitude'])
    sun_y = -cos(sunpos['azimuth'] - dev) * cos(sunpos['altitude'])
    sun_z = sin(sunpos['altitude'])

    sm = ShadowMap(hm.lat, hm.lng, hm.resolution, hm.size, hm.proj, sun_x, sun_y, sun_z, hm, 1.5)
    img = sm.to_image()
    img = img.convert('RGB')

    if bkg:
        img = Image.eval(img, lambda x: x + transparency)
        img = ImageChops.multiply(img, bkg)

    draw = ImageDraw.ImageDraw(img)
    text = t.strftime('%Y-%m-%d %H:%M')
    txtsize = draw.textsize(text)
    draw.text((hm.size - txtsize[0] - 5, hm.size - txtsize[1] - 5), text, (0,0,0))

    img.save(path.join(args.output_directory, t.strftime('%Y-%m-%d_%H%M.png')))

    t += delta
    print()