add contains_points to mpl utils and move mpl utils to mapdata

src/c3nav/mapdata/utils/mpl.py

@@ -0,0 +1,109 @@
+from abc import ABC, abstractmethod
+
+import numpy as np
+from matplotlib.path import Path
+from shapely.geometry import GeometryCollection, MultiPolygon, Polygon
+
+from c3nav.mapdata.utils.geometry import assert_multipolygon
+
+
+class MplPathProxy(ABC):
+    @abstractmethod
+    def intersects_path(self, path):
+        pass
+
+    @abstractmethod
+    def contains_point(self, point):
+        pass
+
+
+class MplMultipolygonPath(MplPathProxy):
+    def __init__(self, polygon):
+        self.polygons = [MplPolygonPath(polygon) for polygon in assert_multipolygon(polygon)]
+
+    @property
+    def exteriors(self):
+        return tuple(polygon.exterior for polygon in self.polygons)
+
+    def intersects_path(self, path, filled=False):
+        for polygon in self.polygons:
+            if polygon.intersects_path(path, filled=filled):
+                return True
+        return False
+
+    def contains_point(self, point):
+        for polygon in self.polygons:
+            if polygon.contains_point(point):
+                return True
+        return False
+
+    def contains_points(self, points):
+        result = np.full((len(points),), fill_value=False, dtype=np.bool)
+        for polygon in self.polygons:
+            ix = np.argwhere(np.logical_not(result)).flatten()
+            result[ix] = polygon.contains_points(points[ix])
+        return result
+
+
+class MplPolygonPath(MplPathProxy):
+    def __init__(self, polygon):
+        self.exterior = linearring_to_mpl_path(polygon.exterior)
+        self.interiors = [linearring_to_mpl_path(interior) for interior in polygon.interiors]
+
+    @property
+    def exteriors(self):
+        return (self.exterior, )
+
+    def intersects_path(self, path, filled=False):
+        if filled:
+            if not self.exterior.intersects_path(path, filled=True):
+                return False
+
+            for interior in self.interiors:
+                if interior.contains_path(path):
+                    return False
+            return True
+        else:
+            if self.exterior.intersects_path(path, filled=False):
+                return True
+
+            for interior in self.interiors:
+                if interior.intersects_path(path, filled=False):
+                    return True
+            return False
+
+    def contains_points(self, points):
+        result = self.exterior.contains_points(points)
+        for interior in self.interiors:
+            if not result.any():
+                break
+            ix = np.argwhere(result).flatten()
+            result[ix] = np.logical_not(interior.contains_points(points[ix]))
+        return result
+
+    def contains_point(self, point):
+        if not self.exterior.contains_point(point):
+            return False
+
+        for interior in self.interiors:
+            if interior.contains_point(point):
+                return False
+        return True
+
+
+def shapely_to_mpl(geometry):
+    """
+    convert a shapely Polygon or Multipolygon to a matplotlib Path
+    :param polygon: shapely Polygon or Multipolygon
+    :return: MplPathProxy
+    """
+    if isinstance(geometry, Polygon):
+        return MplPolygonPath(geometry)
+    elif isinstance(geometry, MultiPolygon) or geometry.is_empty or isinstance(geometry, GeometryCollection):
+        return MplMultipolygonPath(geometry)
+    raise TypeError
+
+
+def linearring_to_mpl_path(linearring):
+    return Path(np.array(linearring),
+                (Path.MOVETO, *([Path.LINETO] * (len(linearring.coords)-2)), Path.CLOSEPOLY), readonly=True)