use helper function to get intersection points for different geometri…

…es (#81)

sleap_roots/convhull.py

@@ -548,18 +548,21 @@ def get_chull_intersection_vectors(
 
     # Get the intersection points
     if not intersection.is_empty:
-        intersect_points = (
-            np.array([[point.x, point.y] for point in intersection.geoms])
-            if intersection.geom_type == "MultiPoint"
-            else np.array([[intersection.x, intersection.y]])
-        )
+        intersect_points = extract_points_from_geometry(intersection)
     else:
         # Return two vectors of NaNs if there is no intersection
         return leftmost_vector, rightmost_vector
 
-    # Get the leftmost and rightmost intersection points
-    leftmost_intersect = intersect_points[np.argmin(intersect_points[:, 0])]
-    rightmost_intersect = intersect_points[np.argmax(intersect_points[:, 0])]
+    # Convert the list of NumPy arrays to a 2D NumPy array
+    intersection_points_array = np.vstack(intersect_points)
+
+    # Find the leftmost and rightmost intersection points
+    leftmost_intersect = intersection_points_array[
+        np.argmin(intersection_points_array[:, 0])
+    ]
+    rightmost_intersect = intersection_points_array[
+        np.argmax(intersection_points_array[:, 0])
+    ]
 
     # Make a vector from the leftmost r0 point to the leftmost intersection point
     leftmost_vector = (leftmost_intersect - leftmost_r0).reshape(1, -1)

sleap_roots/points.py

@@ -8,7 +8,7 @@
 from typing import List, Optional, Tuple
 
 
-def extract_points_from_geometry(geometry):
+def extract_points_from_geometry(geometry) -> List[np.ndarray]:
     """Extracts coordinates as a list of numpy arrays from any given Shapely geometry object.
 
     This function supports Point, MultiPoint, LineString, and GeometryCollection types.

tests/test_convhull.py

@@ -327,7 +327,7 @@ def test_basic_functionality(pts_shape_3_6_2):
         r0_pts, r1_pts, pts, hull
     )
 
-    # Assertions depend on the expected outcome, which you'll need to calculate based on your function's logic
+    # TODO: Add more specific tests as needed
     assert not np.isnan(left_vector).any(), "Left vector should not contain NaNs"
     assert not np.isnan(right_vector).any(), "Right vector should not contain NaNs"