Fix impact being written for non-triggered telescopes, fixes #1961 (#…

…1967)

* Fix impact being written for non-triggered telescopes, fixes #1961

* Fix test now that impacts are only written for triggered telescopes

ctapipe/io/tests/test_table_loader.py

@@ -151,7 +151,7 @@ def test_read_telescope_events_type(test_file_dl2):
         assert "HillasReconstructor_alt" in table.colnames
         assert "true_energy" in table.colnames
         assert "true_image" in table.colnames
-        assert {25, 125, 127}.issubset(set(table["tel_id"].data))
+        assert set(table["tel_id"].data).issubset([25, 125, 130])
         assert "equivalent_focal_length" in table.colnames
         assert "HillasReconstructor_impact_distance" in table.colnames
 

ctapipe/reco/shower_processor.py

@@ -82,8 +82,8 @@ def __call__(self, event: ArrayEventContainer):
             shower_geom=event.dl2.stereo.geometry[k], subarray=self.subarray
         )
 
-        for tel_index, impact_distance in enumerate(impact_distances):
-            tel_id = self.subarray.tel_ids[tel_index]
+        for tel_id in event.trigger.tels_with_trigger:
+            tel_index = self.subarray.tel_indices[tel_id]
             event.dl2.tel[tel_id].impact[k] = TelescopeImpactParameterContainer(
-                distance=impact_distance
+                distance=impact_distances[tel_index]
             )