structure saas with tools

.venv/lib/python3.10/site-packages/shapely/algorithms/cga.py

@@ -0,0 +1,50 @@
+"""Shapely CGA algorithms."""
+
+import numpy as np
+
+import shapely
+
+
+def signed_area(ring):
+    """Return the signed area enclosed by a ring in linear time.
+
+    Algorithm used: https://web.archive.org/web/20080209143651/http://cgafaq.info:80/wiki/Polygon_Area
+    """
+    coords = np.array(ring.coords)[:, :2]
+    xs, ys = np.vstack([coords, coords[1]]).T
+    return np.sum(xs[1:-1] * (ys[2:] - ys[:-2])) / 2.0
+
+
+def _reverse_conditioned(rings, condition):
+    """Return a copy of the rings potentially reversed depending on `condition`."""
+    condition = np.asarray(condition)
+    if np.all(condition):
+        rings = shapely.reverse(rings)
+    elif np.any(condition):
+        rings = np.array(rings)
+        rings[condition] = shapely.reverse(rings[condition])
+    return rings
+
+
+def _orient_polygon(geometry, exterior_cw=False):
+    if geometry is None:
+        return None
+    if geometry.geom_type in ["MultiPolygon", "GeometryCollection"]:
+        return geometry.__class__(
+            [_orient_polygon(geom, exterior_cw) for geom in geometry.geoms]
+        )
+    # elif geometry.geom_type in ["LinearRing"]:
+    #     return reverse_conditioned(geometry, is_ccw(geometry) != ccw)
+    elif geometry.geom_type == "Polygon":
+        rings = np.array([geometry.exterior, *geometry.interiors])
+        reverse_condition = shapely.is_ccw(rings)
+        reverse_condition[0] = not reverse_condition[0]
+        if exterior_cw:
+            reverse_condition = np.logical_not(reverse_condition)
+        if np.any(reverse_condition):
+            rings = _reverse_conditioned(rings, reverse_condition)
+            return geometry.__class__(rings[0], rings[1:])
+    return geometry
+
+
+_orient_polygons_vectorized = np.frompyfunc(_orient_polygon, nin=2, nout=1)