extract.py

from lxml.etree import parse

NS = {'svg': 'http://www.w3.org/2000/svg'}
CMD = 'ctx.{0}({1}, {2});'
FUN = r'''
    function (ctx) {{
        ctx.save();
        ctx.beginPath();
        {0}
        //ctx.closePath();
        ctx.stroke();
        ctx.restore();
    }},
'''


def parse_poly(poly):
    items = []
    lst = [p for p in poly.split(' ') if p]
    items.append(CMD.format('moveTo', *lst[0].split(',')))
    for point in lst:
        items.append(CMD.format('lineTo', *point.split(',')))
    return items


def parse_path(path):
    items = []
    cx, cy = 0, 0
    for cmd in (c for c in path.split(' ') if c):
        c, args = cmd[0], cmd[1:].split(',') if len(cmd) > 1 else []
        line = '#unknown'
        if c == 'M':
            cx, cy = args
            line = 'ctx.moveTo({0}, {1});'.format(*args)
        elif c == 'L':
            cx, cy = args
            line = 'ctx.lineTo({0}, {1});'.format(*args)
        elif c == 'V':
            cy = args[0]
            line = 'ctx.lineTo({0}, {1});'.format(cx, args[0])
        elif c == 'H':
            cx = args[0]
            line = 'ctx.lineTo({0}, {1});'.format(args[0], cy)
        elif c == 'Q' or c == 'C':
            cx, cy = args[4:]
            line = 'ctx.bezierCurveTo({0}, {1}, {2}, {3}, {4}, {5});'.format(*args)
        elif c == 'Z':
            line = 'ctx.closePath();'
        else:
            line = '//unknown({0}, #{1})'.format(c, len(args))
        items.append(line)
    return items


def main(infile):
    tree = parse(infile)
    items = []
    for poly in tree.xpath('svg:g/svg:polygon/@points', namespaces=NS):
        items.append(parse_poly(poly))
    for path in tree.xpath('svg:g/svg:path/@d', namespaces=NS):
        items.append(parse_path(path))
    print("window.funs = [")
    for item in items:
        print(FUN.format(('\n        ').join(item)))
    print("];")

if __name__ == '__main__':
    import sys
    main(sys.argv[1])