Maya: Improve lib.polyConstraint performance when Select tool is not the active tool context

openpype/hosts/maya/api/lib.py

@@ -745,6 +745,33 @@ def namespaced(namespace, new=True):
  cmds.namespace(set=original)
 
 
+@contextlib.contextmanager
+def maintained_selection_api():
+ """Maintain selection using the Maya Python API.
+
+ Warning: This is *not* added to the undo stack.
+
+ """
+ original = om.MGlobal.getActiveSelectionList()
+ try:
+ yield
+ finally:
+ om.MGlobal.setActiveSelectionList(original)
+
+
+@contextlib.contextmanager
+def tool(context):
+ """Set a tool context during the context manager.
+
+ """
+ original = cmds.currentCtx()
+ try:
+ cmds.setToolTo(context)
+ yield
+ finally:
+ cmds.setToolTo(original)
+
+
 def polyConstraint(components, *args, **kwargs):
  """Return the list of *components* with the constraints applied.
 
@@ -763,17 +790,25 @@ def polyConstraint(components, *args, **kwargs):
  kwargs.pop('mode', None)
 
  with no_undo(flush=False):
- with maya.maintained_selection():
- # Apply constraint using mode=2 (current and next) so
- # it applies to the selection made before it; because just
- # a `maya.cmds.select()` call will not trigger the constraint.
- with reset_polySelectConstraint():
- cmds.select(components, r=1, noExpand=True)
- cmds.polySelectConstraint(*args, mode=2, **kwargs)
- result = cmds.ls(selection=True)
- cmds.select(clear=True)
-
- return result
+ # Reverting selection to the original selection using
+ # `maya.cmds.select` can be slow in rare cases where previously
+ # `maya.cmds.polySelectConstraint` had set constrain to "All and Next"
+ # and the "Random" setting was activated. To work around this we
+ # revert to the original selection using the Maya API. This is safe
+ # since we're not generating any undo change anyway.
+ with tool("selectSuperContext"):
+ # Selection can be very slow when in a manipulator mode.
+ # So we force the selection context which is fast.
+ with maintained_selection_api():
+ # Apply constraint using mode=2 (current and next) so
+ # it applies to the selection made before it; because just
+ # a `maya.cmds.select()` call will not trigger the constraint.
+ with reset_polySelectConstraint():
+ cmds.select(components, r=1, noExpand=True)
+ cmds.polySelectConstraint(*args, mode=2, **kwargs)
+ result = cmds.ls(selection=True)
+ cmds.select(clear=True)
+ return result
 
 
 @contextlib.contextmanager