Handle GEOSException: IllegalArgumentException: Invalid number of points in LinearRing found 3 - must be 0 or >= 4

[LoicGoulefert]

Sometimes, linesimplify introduces ill formed LinearRings. Find a way to either:

• convert these ill-formed linear rings into valid ones
• ignore them
• delete them

GEOSException                             Traceback (most recent call last)
<ipython-input-80-8f14df048e4b> in <module>
     49         vsk.geometry(rh.intersection(bundle_lines))
     50 
---> 51 vsk.vpype("linesimplify occult crop 1cm 1cm 26.2cm 19cm reloop linemerge multipass linesort")
     52 vsk.display(mode="matplotlib")

~/Documents/python/vsketch/vsketch/vsketch.py in vpype(self, pipeline)
   1229 
   1230         args = "vsketchinput " + pipeline + " vsketchoutput"
-> 1231         vpype_cli.cli.main(prog_name="vpype", args=shlex.split(args), standalone_mode=False)
   1232 
   1233     def display(

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/vpype_cli/cli.py in main(self, args, **extra)
     72         if args is None:
     73             args = get_os_args()
---> 74         return super().main(args=preprocess_argument_list(args), **extra)
     75 
     76 

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/click/core.py in main(self, args, prog_name, complete_var, standalone_mode, **extra)
    780             try:
    781                 with self.make_context(prog_name, args, **extra) as ctx:
--> 782                     rv = self.invoke(ctx)
    783                     if not standalone_mode:
    784                         return rv

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/click/core.py in invoke(self, ctx)
   1288                 with sub_ctx:
   1289                     rv.append(sub_ctx.command.invoke(sub_ctx))
-> 1290             return _process_result(rv)
   1291 
   1292     def resolve_command(self, ctx, args):

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/click/core.py in _process_result(value)
   1222         def _process_result(value):
   1223             if self.result_callback is not None:
-> 1224                 value = ctx.invoke(self.result_callback, value, **ctx.params)
   1225             return value
   1226 

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/click/core.py in invoke(*args, **kwargs)
    608         with augment_usage_errors(self):
    609             with ctx:
--> 610                 return callback(*args, **kwargs)
    611 
    612     def forward(*args, **kwargs):  # noqa: B902

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/vpype_cli/cli.py in process_pipeline(processors, verbose, include, history, seed, config)
    126 @cli.resultcallback()
    127 def process_pipeline(processors, verbose, include, history, seed, config):
--> 128     execute_processors(processors)
    129 
    130 

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/vpype_cli/cli.py in execute_processors(processors)
    210     state = vp.VpypeState()
    211     for proc in outer_processors:
--> 212         state = proc(state)
    213     return state
    214 

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/vpype/decorators.py in layer_processor(state)
     83                 start = datetime.datetime.now()
     84                 with state.current():
---> 85                     state.document[lid] = f(state.document[lid], *args, **kwargs)
     86                 stop = datetime.datetime.now()
     87 

~/Documents/python/occult/occult/occult.py in occult(lines, tolerance)
     44         if math.hypot(coords[-1, 0] - coords[0, 0], coords[-1, 1] - coords[0, 1]) < tolerance:
     45             tree = pygeos.STRtree(line_arr[:i])
---> 46             p = pygeos.polygons(coords)
     47             geom_idx = tree.query(p, predicate="intersects")
     48             line_arr[geom_idx] = pygeos.set_operations.difference(line_arr[geom_idx], p)

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/pygeos/creation.py in polygons(shells, holes)
     85     shells = np.asarray(shells)
     86     if not isinstance(shells, Geometry) and np.issubdtype(shells.dtype, np.number):
---> 87         shells = linearrings(shells)
     88 
     89     if holes is None:

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/pygeos/creation.py in linearrings(coords, y, z)
     69     z : array_like
     70     """
---> 71     return _wrap_construct_ufunc(lib.linearrings, coords, y, z)
     72 
     73 

~/Documents/python/vsketch/venv/lib/python3.6/site-packages/pygeos/creation.py in _wrap_construct_ufunc(func, coords, y, z)
     18 def _wrap_construct_ufunc(func, coords, y=None, z=None):
     19     if y is None:
---> 20         return func(coords)
     21     x = coords
     22     if z is None:

GEOSException: IllegalArgumentException: Invalid number of points in LinearRing found 3 - must be 0 or >= 4