Recovered patch.py

descartes/patch.py

@@ -0,0 +1,66 @@
+"""Paths and patches"""
+
+from matplotlib.patches import PathPatch
+from matplotlib.path import Path
+from numpy import asarray, concatenate, ones
+
+
+class Polygon(object):
+    # Adapt Shapely or GeoJSON/geo_interface polygons to a common interface
+    def __init__(self, context):
+        if hasattr(context, 'interiors'):
+            self.context = context
+        else:
+            self.context = getattr(context, '__geo_interface__', context)
+    @property
+    def geom_type(self):
+        return (getattr(self.context, 'geom_type', None)
+                or self.context['type'])
+    @property
+    def exterior(self):
+        return (getattr(self.context, 'exterior', None) 
+                or self.context['coordinates'][0])
+    @property
+    def interiors(self):
+        value = getattr(self.context, 'interiors', None)
+        if value is None:
+            value = self.context['coordinates'][1:]
+        return value
+
+
+def PolygonPath(polygon):
+    """Constructs a compound matplotlib path from a Shapely or GeoJSON-like
+    geometric object"""
+    this = Polygon(polygon)
+    assert this.geom_type == 'Polygon'
+    def coding(ob):
+        # The codes will be all "LINETO" commands, except for "MOVETO"s at the
+        # beginning of each subpath
+        n = len(getattr(ob, 'coords', None) or ob)
+        vals = ones(n, dtype=Path.code_type) * Path.LINETO
+        vals[0] = Path.MOVETO
+        return vals
+    vertices = concatenate(
+                    [asarray(this.exterior)] 
+                    + [asarray(r) for r in this.interiors])
+    codes = concatenate(
+                [coding(this.exterior)] 
+                + [coding(r) for r in this.interiors])
+    return Path(vertices, codes)
+
+
+def PolygonPatch(polygon, **kwargs):
+    """Constructs a matplotlib patch from a geometric object
+    
+    The `polygon` may be a Shapely or GeoJSON-like object with or without holes.
+    The `kwargs` are those supported by the matplotlib.patches.Polygon class
+    constructor. Returns an instance of matplotlib.patches.PathPatch.
+
+    Example (using Shapely Point and a matplotlib axes):
+
+      >>> b = Point(0, 0).buffer(1.0)
+      >>> patch = PolygonPatch(b, fc='blue', ec='blue', alpha=0.5)
+      >>> axis.add_patch(patch)
+
+    """
+    return PathPatch(PolygonPath(polygon), **kwargs)