import matplotlib.pyplot as plt
import matplotlib.path as mpath
import matplotlib.patches as patches
import ogr
import numpy as np
from copy import copy
%matplotlib inline

def geom2path(geom):
    # function to convert a OGR geometry object to
    # a Matplotlib Path
    
    allverts = None
    allcodes = None

    for poly in geom:
        for ring in poly:

            listring = ring.ExportToWkt().replace('LINEARRING (','').replace(')','').split(',')
            
            # itertools.izip for python 2
            xs, ys = zip(*[vert.split(' ') for vert in listring])
            verts = np.array([xs, ys], dtype='float32')
            
            codes = len(xs) * [mpath.Path.LINETO]
            # Make the first code a MOVETO, prevents
            # a line being drawn between parts or 
            # between outer and inner rings.
            codes[0] = mpath.Path.MOVETO

            if not allverts is None:
                allverts = np.concatenate([allverts, verts], axis=1)
                allcodes = np.concatenate([allcodes, codes], axis=1)
            else:
                allverts = verts
                allcodes = codes

    mpl_path = mpath.Path(allverts.swapaxes(0,1), allcodes)
    
    return mpl_path

# example from:
# http://en.wikipedia.org/wiki/Well-known_text#Geometric_objects
inwkt = 'MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)),((20 35, 10 30, 10 10, 30 5, 45 20, 20 35),(30 20, 20 15, 20 25, 30 20)))'

# parse the WKT to a OGR Geometry
geom = ogr.CreateGeometryFromWkt(inwkt)

mpl_path, verts, codes = geom2path(geom)

# convert to Path Patch
mypatch = patches.PathPatch(mpl_path, 
                            facecolor='orange', lw=2)

fig, ax = plt.subplots(subplot_kw={'aspect': 1.0,
                                   'xlim': [0, 50],
                                   'ylim': [0,50]})

ax.add_patch(copy(mypatch))