add testPointInstances test for exercising UFE scene item and path ha…

…ndling of point instances

test/lib/ufe/CMakeLists.txt

@@ -27,6 +27,7 @@ if(CMAKE_UFE_V2_FEATURES_AVAILABLE)
         testObject3d.py
         testRename.py
         testParentCmd.py
+        testPointInstances.py
         testReorderCmd.py
         testRotateCmd.py
         testRotatePivot.py

test/lib/ufe/testPointInstances.py

@@ -0,0 +1,140 @@
+#!/usr/bin/env mayapy
+#
+# Copyright 2020 Autodesk
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+import mayaUtils
+import usdUtils
+
+from mayaUsd import ufe as mayaUsdUfe
+
+from pxr import UsdGeom
+
+from maya import cmds
+
+import ufe
+
+import unittest
+
+
+class PointInstancesTestCase(unittest.TestCase):
+    '''
+    Tests that the UFE path and scene item interfaces work as expected when
+    working with USD point instances.
+    '''
+
+    _pluginsLoaded = False
+
+    @classmethod
+    def setUpClass(cls):
+        if not cls._pluginsLoaded:
+            cls._pluginsLoaded = mayaUtils.isMayaUsdPluginLoaded()
+
+    def setUp(self):
+        self.assertTrue(self._pluginsLoaded)
+
+        mayaUtils.openPointInstancesGrid14Scene()
+
+    def testPointInstances(self):
+        # Create a UFE path to a PointInstancer prim with an instanceIndex on
+        # the end. This path uniquely identifies a specific point instance.
+        ufePath = ufe.Path([
+            mayaUtils.createUfePathSegment('|UsdProxy|UsdProxyShape'),
+            usdUtils.createUfePathSegment('/PointInstancerGrid/PointInstancer/7')])
+        ufeItem = ufe.Hierarchy.createItem(ufePath)
+
+        # Verify that we turned the path into a scene item correctly and that
+        # we can access the PointInstancer prim.
+        self.assertEqual(ufeItem.nodeType(), 'PointInstancer')
+
+        ufeAttrs = ufe.Attributes.attributes(ufeItem)
+        self.assertTrue(ufeAttrs.hasAttribute(UsdGeom.Tokens.positions))
+
+        # XXX: Note that UsdSceneItem currently has no wrapping to Python, so
+        # we are not able to verify that we can query the scene item directly
+        # for its instance index. We can exercise the Utils functions though.
+
+        ufePathString = ufe.PathString.string(ufePath)
+
+        prim = mayaUsdUfe.ufePathToPrim(ufePathString)
+        self.assertTrue(prim)
+        self.assertTrue(prim.IsA(UsdGeom.PointInstancer))
+
+        instanceIndex = mayaUsdUfe.ufePathToInstanceIndex(ufePathString)
+        self.assertEqual(instanceIndex, 7)
+
+        # Tests for the usdPathToUfePathSegment() utility function.
+        ufePathSegmentString = mayaUsdUfe.usdPathToUfePathSegment(prim.GetPrimPath())
+        self.assertEqual(ufePathSegmentString, '/PointInstancerGrid/PointInstancer')
+
+        ufePathSegmentString = mayaUsdUfe.usdPathToUfePathSegment(prim.GetPrimPath(), 7)
+        self.assertEqual(ufePathSegmentString, '/PointInstancerGrid/PointInstancer/7')
+
+        ufePrimPathString = mayaUsdUfe.stripInstanceIndexFromUfePath(ufePathString)
+        self.assertEqual(
+            ufePrimPathString,
+            '|UsdProxy|UsdProxyShape,/PointInstancerGrid/PointInstancer')
+
+        # Create a path to the PointInstancer itself and verify that the
+        # instanceIndex is ALL_INSTANCES.
+        # XXX: Ideally we would use a named constant provided by
+        # UsdImagingDelegate for ALL_INSTANCES, but currently that library does
+        # not have any Python wrapping. We *could* get it indirectly as
+        # UsdImagingGL.ALL_INSTANCES, but that would bring unnecessary baggage
+        # with it, so we just re-define it here.
+        ALL_INSTANCES = -1
+
+        ufePath = ufe.Path([
+            mayaUtils.createUfePathSegment('|UsdProxy|UsdProxyShape'),
+            usdUtils.createUfePathSegment('/PointInstancerGrid/PointInstancer')])
+        ufePathString = ufe.PathString.string(ufePath)
+
+        instanceIndex = mayaUsdUfe.ufePathToInstanceIndex(ufePathString)
+        self.assertEqual(instanceIndex, ALL_INSTANCES)
+
+        # Create a path to a non-PointInstancer prim but append an instance
+        # index to it. This isn't really a valid path, but the utility function
+        # should recognize this case and return an instanceIndex of
+        # ALL_INSTANCES.
+        ufePath = ufe.Path([
+            mayaUtils.createUfePathSegment('|UsdProxy|UsdProxyShape'),
+            usdUtils.createUfePathSegment('/PointInstancerGrid/7')])
+        ufePathString = ufe.PathString.string(ufePath)
+
+        instanceIndex = mayaUsdUfe.ufePathToInstanceIndex(ufePathString)
+        self.assertEqual(instanceIndex, ALL_INSTANCES)
+
+    def testPickWalking(self):
+        '''
+        Tests pick-walking from a point instance up to the PointInstancer that
+        generated it.
+        '''
+        ufePath = ufe.Path([
+            mayaUtils.createUfePathSegment('|UsdProxy|UsdProxyShape'),
+            usdUtils.createUfePathSegment('/PointInstancerGrid/PointInstancer/7')])
+        ufeItem = ufe.Hierarchy.createItem(ufePath)
+
+        globalSelection = ufe.GlobalSelection.get()
+        globalSelection.append(ufeItem)
+
+        # Pick-walk up from the point instance.
+        cmds.pickWalk(direction='up')
+
+        # The selection should have been replaced with the PointInstancer
+        ufeItem = globalSelection.front()
+        ufePathString = ufe.PathString.string(ufeItem.path())
+        self.assertEqual(
+            ufePathString,
+            '|UsdProxy|UsdProxyShape,/PointInstancerGrid/PointInstancer')