added trigger_overlap to polygon_zone

supervision/detection/tools/polygon_zone.py

@@ -89,6 +89,45 @@ def trigger(self, detections: Detections) -> npt.NDArray[np.bool_]:
         self.current_count = int(np.sum(is_in_zone))
         return is_in_zone.astype(bool)
 
+    def trigger_overlap(
+        self, detections: Detections, overlap_threshold: float
+    ) -> npt.NDArray[np.bool_]:
+        """
+        Determines if the detections are within the polygon zone.
+
+        Parameters:
+            detections (Detections): The detections
+                to be checked against the polygon zone
+
+            overlap_threshold (float): threshold of overlap
+
+        Returns:
+            np.ndarray: A boolean numpy array indicating
+                if each detection overlaps the polygon zone
+        """
+
+        clipped_xyxy = clip_boxes(
+            xyxy=detections.xyxy, resolution_wh=self.frame_resolution_wh
+        )
+        clipped_detections = replace(detections, xyxy=clipped_xyxy)
+        overlap_results: npt.NDArray[np.bool_] = np.zeros(
+            len(clipped_detections), dtype=bool
+        )
+
+        masks = []
+        for i, (x1, y1, x2, y2) in enumerate(detections.xyxy.astype(np.int32)):
+            bbox_mask = np.zeros_like(self.mask, dtype=bool)
+
+            bbox_mask[y1:y2, x1:x2] = True
+            masks.append(bbox_mask)
+            overlap_ratio = (
+                np.count_nonzero(np.logical_and(bbox_mask, self.mask))
+                / detections.area[i]
+            )
+            overlap_results[i] = overlap_ratio >= overlap_threshold
+
+        return overlap_results
+
 
 class PolygonZoneAnnotator:
     """

test/detection/test_polygonzone.py

@@ -92,3 +92,85 @@ def test_polygon_zone_trigger(
     with exception:
         in_zone = polygon_zone.trigger(detections)
         assert np.all(in_zone == expected_results)
+
+
+@pytest.mark.parametrize(
+    "detections, polygon_zone, overlap_threshold, expected_results, exception",
+    [
+        # Test cases for trigger_overlap function
+        (
+            DETECTIONS,
+            sv.PolygonZone(
+                POLYGON,
+                FRAME_RESOLUTION,
+                triggering_anchors=(
+                    sv.Position.TOP_LEFT,
+                    sv.Position.TOP_RIGHT,
+                    sv.Position.BOTTOM_LEFT,
+                    sv.Position.BOTTOM_RIGHT,
+                ),
+            ),
+            0.25,  # Overlap threshold
+            np.array(
+                [False, False, True, True, True, True, True, False, False], dtype=bool
+            ),
+            DoesNotRaise(),
+        ),  # Case with specific overlap threshold
+        (
+            DETECTIONS,
+            sv.PolygonZone(
+                POLYGON,
+                FRAME_RESOLUTION,
+            ),
+            0.5,  # Overlap threshold
+            np.array(
+                [False, False, False, True, True, True, False, False, False], dtype=bool
+            ),
+            DoesNotRaise(),
+        ),  # Another overlap threshold
+        (
+            DETECTIONS,
+            sv.PolygonZone(
+                POLYGON,
+                FRAME_RESOLUTION,
+            ),
+            0.1,  # Lower overlap threshold to catch more detections
+            np.array(
+                [False, False, True, True, True, True, True, False, False], dtype=bool
+            ),
+            DoesNotRaise(),
+        ),  # Lower threshold test
+        (
+            DETECTIONS,
+            sv.PolygonZone(
+                POLYGON,
+                FRAME_RESOLUTION,
+            ),
+            0,  # Lower overlap threshold to catch more detections
+            np.array(
+                [True, True, True, True, True, True, True, True, True], dtype=bool
+            ),
+            DoesNotRaise(),
+        ),  # Lower threshold test
+        (
+            sv.Detections.empty(),
+            sv.PolygonZone(
+                POLYGON,
+                FRAME_RESOLUTION,
+            ),
+            0,
+            np.array([], dtype=bool),
+            DoesNotRaise(),
+        ),  # Test empty detections
+    ],
+)
+def test_polygon_zone_overlap(
+    detections: sv.Detections,
+    polygon_zone: sv.PolygonZone,
+    overlap_threshold: float,
+    expected_results: np.ndarray,
+    exception: Exception,
+) -> None:
+    with exception:
+        overlaps = polygon_zone.trigger_overlap(detections, overlap_threshold)
+        assert np.all(overlaps == expected_results)