Python binding: add iteration support for Poses and Landmark Observations

pyTests/sfmData/test_landmark.py

@@ -14,7 +14,7 @@
 #            image::RGBColor& color) / not binded
 # - operator==(other) => DONE
 # - [inline] operator!=(other) => DONE
-# - Observations& getObservations() / Observations (stl::flat_map) not binded
+# - Observations& getObservations() => DONE (returns MapObservations copy)
 ##################
 
 def test_landmark_default_constructor():
@@ -53,7 +53,25 @@ def test_landmark_compare():
     # TODO: Update the describer type, the Vec3 or the image before comparing again
 
 
-@pytest.mark.skip(reason="stl::flat_map<Observation> not binded")
 def test_landmark_get_observations():
-    """ Test creating Landmarks and retrieving their Observations. """
-    assert True
+    """ Test creating a Landmark and retrieving its (empty) Observations. """
+    landmark = av.Landmark()
+    observations = landmark.getObservations()
+
+    # A default Landmark has no observations
+    assert len(observations) == 0, \
+        "A default Landmark should have no observations"
+
+    # Verify the observations container is iterable and dict-like
+    iterated_ids = [obs_id for obs_id in observations]
+    assert iterated_ids == [], \
+        "Iterating over empty observations should yield no items"
+
+    keys = observations.keys()
+    assert len(keys) == 0, "keys() on empty observations should return an empty list"
+
+    values = observations.values()
+    assert len(values) == 0, "values() on empty observations should return an empty list"
+
+    items = observations.items()
+    assert len(items) == 0, "items() on empty observations should return an empty list"

pyTests/sfmData/test_sfmdata.py

@@ -83,6 +83,45 @@ def test_sfmdata_get_poses():
     assert len(data.getPoses()) == len(poses) == 1, "The list of Poses should have been updated"
 
 
+def test_sfmdata_iterate_poses():
+    """ Test creating an SfMData object, filling it with Poses, and iterating over them. """
+    data = av.SfMData()
+    poses = data.getPoses()
+
+    pose_ids = [1, 2, 3, 4, 5]
+    for pose_id in pose_ids:
+        camera_pose = av.CameraPose()
+        poses[pose_id] = camera_pose
+
+    assert len(poses) == len(pose_ids), "The list of Poses should contain all added Poses"
+
+    # Test __iter__: iterating yields all pose IDs
+    iterated_ids = [pose_id for pose_id in poses]
+    assert sorted(iterated_ids) == sorted(pose_ids), \
+        "Iterating over Poses should yield all pose IDs"
+
+    # Test keys()
+    keys = poses.keys()
+    assert sorted(keys) == sorted(pose_ids), \
+        "keys() should return all pose IDs"
+
+    # Test values()
+    values = poses.values()
+    assert len(values) == len(pose_ids), \
+        "values() should return one CameraPose per pose ID"
+    assert all(isinstance(v, av.CameraPose) for v in values), \
+        "Each value returned by values() should be a CameraPose"
+
+    # Test items()
+    items = poses.items()
+    assert len(items) == len(pose_ids), \
+        "items() should return one (pose_id, CameraPose) pair per pose"
+    for pose_id, pose in items:
+        assert pose_id in pose_ids, "Each key from items() should be a valid pose ID"
+        assert isinstance(pose, av.CameraPose), \
+            "Each value from items() should be a CameraPose"
+
+
 def test_sfmdata_get_rigs():
     """ Test creating an empty SfMData object, retrieving and editing its Rigs. """
     data = av.SfMData()

src/aliceVision/sfmData/Landmark.i

@@ -23,6 +23,10 @@
 %ignore aliceVision::sfmData::Landmark::_X;
 %ignore aliceVision::sfmData::Landmark::_pointFetcher;
 
+// Ignore getObservations() which returns stl::flat_map (not natively supported by SWIG).
+// A compatible replacement returning MapObservations (std::map) is provided via %extend below.
+%ignore aliceVision::sfmData::Landmark::getObservations;
+
 //Add new swig only C++ code
 %extend aliceVision::sfmData::Landmark {
 
@@ -45,6 +49,12 @@
         color.b() = value.z();
         $self->setRgb(color);
     }
+
+    // Return observations as a std::map (MapObservations) so that SWIG can expose
+    // a fully iterable Python dict-like object.
+    aliceVision::sfmData::MapObservations getObservations() const {
+        return $self->getMapObservations();
+    }
 
     // If the user asks for the rgb property
     // It is not a direct access to the rgb