[core] Node: stopComputation method

- Node: stopComputation method.
- Task Manager: avoid stopping the entire task manager when a node is stopped.

meshroom/core/node.py

@@ -788,6 +788,12 @@ class BaseNode(BaseObject):
     def endSequence(self):
         pass
 
+    def stopComputation(self):
+        """ Stop the computation of this node. """
+        for chunk in self._chunks.values():
+            if not chunk.isExtern():
+                chunk.stopProcess()
+
     def getGlobalStatus(self):
         """
         Get node global status based on the status of its chunks.

meshroom/core/taskManager.py

@@ -56,9 +56,7 @@ class TaskThread(Thread):
                     chunk.process(self.forceCompute)
                 except Exception as e:
                     if chunk.isStopped():
-                        self._state = State.STOPPED
+                        pass
-                        self._manager._graph.clearSubmittedNodes()
-                        self._manager._nodesToProcess = []
                     else:
                         logging.error("Error on node computation: {}".format(e))
                         nodesToRemove, _ = self._manager._graph.nodesFromNode(node)