ADD: Callbacks to NeuronavigationAPI, allowing controlling InVesalius (#441)

Olli-Pekka Kahilakoski · GitHub
1 parent 8e5c5977
Showing 1 changed file with 26 additions and 5 deletions Show diff stats
invesalius/net/neuronavigation_api.py
@@ -28,20 +28,26 @@ class NeuronavigationApi(metaclass=Singleton):
     An API used internally in InVesalius to communicate with the
     outside world.
-    When something noteworthy happens when running InVesalius, e.g.,
-    the coil is moved during neuronavigation, an object created from
-    this class can be used to update that information.
+    When an event of one of several types happens while running InVesalius, e.g.,
+    the coil is moved during neuronavigation, this class is used to update the
+    information conveyed by the event.
     When created for the first time, takes a connection object obtained
     from outside InVesalius (see the main entrypoint in app.py).
-    If connection object is not given or it is None, skip doing the updates.
+    The owner of the connection object can update the state of InVesalius by implementing
+    functions to set callbacks, used then to communicate the new state to InVesalius (see,
+    e.g., set_callback__set_markers below).
+
+    If connection object is not given or it is None, do not do the updates.
     """
     N_VERTICES_IN_POLYGON = 3
     def __init__(self, connection=None):
         if connection is not None:
-            assert self._hasmethod(connection, 'update_coil_pose')
+            self.assert_valid(connection)
+
+            self.__set_callbacks(connection)
             self.__bind_events()
         self.connection = connection
@@ -49,9 +55,16 @@ class NeuronavigationApi(metaclass=Singleton):
     def _hasmethod(self, obj, name):
         return hasattr(obj, name) and callable(getattr(obj, name))
+    def assert_valid(self, connection):
+        assert self._hasmethod(connection, 'update_coil_pose')
+        assert self._hasmethod(connection, 'update_focus')
+        assert self._hasmethod(connection, 'set_callback__set_markers')
+
     def __bind_events(self):
         Publisher.subscribe(self.update_focus, 'Set cross focal point')
+    # Functions for InVesalius to send updates.
+
     # TODO: Not the cleanest API; for an example of a better API, see update_coil_pose
     #   below, for which position and orientation are sent separately. Changing this
     #   would require changing 'Set cross focal point' publishers and subscribers
@@ -96,3 +109,11 @@ class NeuronavigationApi(metaclass=Singleton):
                 points=points,
                 polygons=polygons,
             )
+
+    # Functions for InVesalius to receive updates via callbacks.
+
+    def __set_callbacks(self, connection):
+        connection.set_callback__set_markers(self.set_markers)
+
+    def set_markers(self, markers):
+        Publisher.sendMessage('Set markers', markers=markers)