[Fix] Flip yaw angle for DepthInstance3DBoxes.overlaps

mmdet3d/core/bbox/structures/depth_box3d.py

@@ -268,3 +268,32 @@ def get_surface_line_center(self):
         line_center = center.repeat(1, 12, 1).reshape(-1, 3) + line_3d
 
         return surface_center, line_center
+
+    @classmethod
+    def overlaps(cls, boxes1, boxes2, mode='iou'):
+        """Calculate 3D overlaps of two boxes.
+
+        Note:
+            This function calculates the overlaps between ``boxes1`` and
+            ``boxes2``, ``boxes1`` and ``boxes2`` should be in the same type.
+        Args:
+            boxes1 (:obj:`BaseInstance3DBoxes`): Boxes 1 contain N boxes.
+            boxes2 (:obj:`BaseInstance3DBoxes`): Boxes 2 contain M boxes.
+            mode (str, optional): Mode of iou calculation. Defaults to 'iou'.
+        Returns:
+            torch.Tensor: Calculated 3D overlaps of the boxes.
+        """
+        # We flip yaw angle here as mmcv.ops.box_iou_rotated accepts
+        # it in anti-clockwise direction.
+        if boxes1.with_yaw:
+            tensor1 = torch.cat(
+                (boxes1.tensor[:, :-1], -boxes1.tensor[:, -1:]), dim=-1)
+            boxes1 = DepthInstance3DBoxes(
+                tensor1, box_dim=boxes1.box_dim, with_yaw=boxes1.with_yaw)
+        if boxes2.with_yaw:
+            tensor2 = torch.cat(
+                (boxes2.tensor[:, :-1], -boxes2.tensor[:, -1:]), dim=-1)
+            boxes2 = DepthInstance3DBoxes(
+                tensor2, box_dim=boxes2.box_dim, with_yaw=boxes2.with_yaw)
+
+        return super().overlaps(boxes1, boxes2)